text: /*
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version 2
   * of the License, or (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
   *
   * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
   * All rights reserved.
   */
  
  /** \file
   * \ingroup edobj
   */
  
  #include <stdio.h>
  #include <string.h>
  
  #include "MEM_guardedalloc.h"
  
  #include "BLI_blenlib.h"
  #include "BLI_dynstr.h"
  #include "BLI_math.h"
  #include "BLI_utildefines.h"
  
  #include "BLT_translation.h"
  
  #include "DNA_anim_types.h"
  #include "DNA_armature_types.h"
  #include "DNA_constraint_types.h"
  #include "DNA_curve_types.h"
  #include "DNA_object_types.h"
  #include "DNA_scene_types.h"
  #include "DNA_text_types.h"
  
  #include "BIK_api.h"
  #include "BKE_action.h"
  #include "BKE_armature.h"
  #include "BKE_constraint.h"
  #include "BKE_context.h"
  #include "BKE_fcurve.h"
  #include "BKE_main.h"
  #include "BKE_object.h"
  #include "BKE_report.h"
  #include "BKE_tracking.h"
  
  #include "DEG_depsgraph.h"
  #include "DEG_depsgraph_build.h"
  #include "DEG_depsgraph_query.h"
  
  #ifdef WITH_PYTHON
  #  include "BPY_extern.h"
  #endif
  
  #include "WM_api.h"
  #include "WM_types.h"
  
  #include "RNA_access.h"
  #include "RNA_define.h"
  #include "RNA_enum_types.h"
  
  #include "ED_keyframing.h"
  #include "ED_object.h"
  #include "ED_screen.h"
  
  #include "UI_interface.h"
  #include "UI_resources.h"
  
  #include "object_intern.h"
  
  /* ------------------------------------------------------------------- */
  /** \name Constraint Data Accessors
   * \{ */
  
  /**
   * If object is in pose-mode, return active bone constraints, else object constraints.
   * No constraints are returned for a bone on an inactive bone-layer.
   */
  ListBase *ED_object_constraint_active_list(Object *ob)
  {
    if (ob == NULL) {
      return NULL;
    }
  
    if (ob->mode & OB_MODE_POSE) {
      bPoseChannel *pchan;
  
      pchan = BKE_pose_channel_active(ob);
      if (pchan) {
        return &pchan->constraints;
      }
    }
    else {
      return &ob->constraints;
    }
  
    return NULL;
  }
  
  /**
   * Get the constraints for the active pose bone. Bone may be on an inactive bone-layer
   * (unlike #ED_object_constraint_active_list, such constraints are not excluded here).
   */
  ListBase *ED_object_pose_constraint_list(const bContext *C)
  {
    bPoseChannel *pose_bone = CTX_data_pointer_get(C, "active_pose_bone").data;
    if (pose_bone == NULL) {
      pose_bone = CTX_data_pointer_get(C, "pose_bone").data;
      if (pose_bone == NULL) {
        return NULL;
      }
    }
  
    return &pose_bone->constraints;
  }
  
  /* Find the list that a given constraint belongs to,
   * and/or also get the posechannel this is from (if applicable) */
  ListBase *ED_object_constraint_list_from_constraint(Object *ob,
                                                      bConstraint *con,
                                                      bPoseChannel **r_pchan)
  {
    if (r_pchan) {
      *r_pchan = NULL;
    }
  
    if (ELEM(NULL, ob, con)) {
      return NULL;
    }
  
    /* try object constraints first */
    if ((BLI_findindex(&ob->constraints, con) != -1)) {
      return &ob->constraints;
    }
  
    /* if armature, try pose bones too */
    if (ob->pose) {
      bPoseChannel *pchan;
  
      /* try each bone in order
       * NOTE: it's not possible to directly look up the active bone yet, so this will have to do
       */
      for (pchan = ob->pose->chanbase.first; pchan; pchan = pchan->next) {
        if ((BLI_findindex(&pchan->constraints, con) != -1)) {
  
          if (r_pchan) {
            *r_pchan = pchan;
          }
  
          return &pchan->constraints;
        }
      }
    }
  
    /* done */
    return NULL;
  }
  
  /* single constraint */
  bConstraint *ED_object_constraint_active_get(Object *ob)
  {
    return BKE_constraints_active_get(ED_object_constraint_active_list(ob));
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name PyConstraints (Unused)
   * \{ */
  
  #ifdef WITH_PYTHON
  
  /* this callback sets the text-file to be used for selected menu item */
  static void validate_pyconstraint_cb(Main *bmain, void *arg1, void *arg2)
  {
    bPythonConstraint *data = arg1;
    Text *text = NULL;
    int index = *((int *)arg2);
    int i;
  
    /* exception for no script */
    if (index) {
      /* innovative use of a for...loop to search */
      for (text = bmain->texts.first, i = 1; text && index != i; i++, text = text->id.next) {
        /* pass */
      }
    }
    data->text = text;
  }
  
  /* this returns a string for the list of usable pyconstraint script names */
  static char *buildmenu_pyconstraints(Main *bmain, Text *con_text, int *pyconindex)
  {
    DynStr *pupds = BLI_dynstr_new();
    Text *text;
    char *str;
    char buf[64];
    int i;
  
    /* add title first */
    sprintf(buf, "Scripts: %%t|[None]%%x0|");
    BLI_dynstr_append(pupds, buf);
  
    /* init active-index first */
    if (con_text == NULL) {
      *pyconindex = 0;
    }
  
    /* loop through markers, adding them */
    for (text = bmain->texts.first, i = 1; text; i++, text = text->id.next) {
      /* this is important to ensure that right script is shown as active */
      if (text == con_text) {
        *pyconindex = i;
      }
  
      /* only include valid pyconstraint scripts */
      if (BPY_is_pyconstraint(text)) {
        BLI_dynstr_append(pupds, text->id.name + 2);
  
        sprintf(buf, "%%x%d", i);
        BLI_dynstr_append(pupds, buf);
  
        if (text->id.next) {
          BLI_dynstr_append(pupds, "|");
        }
      }
    }
  
    /* convert to normal MEM_malloc'd string */
    str = BLI_dynstr_get_cstring(pupds);
    BLI_dynstr_free(pupds);
  
    return str;
  }
  #endif /* WITH_PYTHON */
  
  #if 0 /* UNUSED, until pyconstraints are added back. */
  /* this callback gets called when the 'refresh' button of a pyconstraint gets pressed */
  static void update_pyconstraint_cb(void *arg1, void *arg2)
  {
  #  ifndef WITH_PYTHON
    (void)arg1; /* unused */
    (void)arg2; /* unused */
  #  else
    Object *owner = (Object *)arg1;
    bConstraint *con = (bConstraint *)arg2;
    if (owner && con) {
      BPY_pyconstraint_update(owner, con);
    }
  #  endif
  }
  #endif /* UNUSED */
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Add Constraint Utilities
   * \{ */
  
  /* helper function for add_constriant - sets the last target for the active constraint */
  static void set_constraint_nth_target(bConstraint *con,
                                        Object *target,
                                        const char subtarget[],
                                        int index)
  {
    const bConstraintTypeInfo *cti = BKE_constraint_typeinfo_get(con);
    ListBase targets = {NULL, NULL};
    bConstraintTarget *ct;
    int num_targets, i;
  
    if (cti && cti->get_constraint_targets) {
      cti->get_constraint_targets(con, &targets);
      num_targets = BLI_listbase_count(&targets);
  
      if (index < 0) {
        if (abs(index) < num_targets) {
          index = num_targets - abs(index);
        }
        else {
          index = num_targets - 1;
        }
      }
      else if (index >= num_targets) {
        index = num_targets - 1;
      }
  
      for (ct = targets.first, i = 0; ct; ct = ct->next, i++) {
        if (i == index) {
          ct->tar = target;
          BLI_strncpy(ct->subtarget, subtarget, sizeof(ct->subtarget));
          break;
        }
      }
  
      if (cti->flush_constraint_targets) {
        cti->flush_constraint_targets(con, &targets, 0);
      }
    }
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Constraint Sanity Testing
   * \{ */
  
  static void test_constraint(
      Main *bmain, Object *owner, bPoseChannel *pchan, bConstraint *con, int type)
  {
    const bConstraintTypeInfo *cti = BKE_constraint_typeinfo_get(con);
    ListBase targets = {NULL, NULL};
    bConstraintTarget *ct;
    bool check_targets = true;
  
    /* clear disabled-flag first */
    con->flag &= ~CONSTRAINT_DISABLE;
  
    if (con->type == CONSTRAINT_TYPE_KINEMATIC) {
      bKinematicConstraint *data = con->data;
  
      /* bad: we need a separate set of checks here as poletarget is
       * optional... otherwise poletarget must exist too or else
       * the constraint is deemed invalid
       */
      /* default IK check ... */
      if (BKE_object_exists_check(bmain, data->tar) == 0) {
        data->tar = NULL;
        con->flag |= CONSTRAINT_DISABLE;
      }
      else if (data->tar == owner) {
        if (!BKE_armature_find_bone_name(BKE_armature_from_object(owner), data->subtarget)) {
          con->flag |= CONSTRAINT_DISABLE;
        }
      }
  
      if (data->poletar) {
        if (BKE_object_exists_check(bmain, data->poletar) == 0) {
          data->poletar = NULL;
          con->flag |= CONSTRAINT_DISABLE;
        }
        else if (data->poletar == owner) {
          if (!BKE_armature_find_bone_name(BKE_armature_from_object(owner), data->polesubtarget)) {
            con->flag |= CONSTRAINT_DISABLE;
          }
        }
      }
      /* ... can be overwritten here */
      BIK_test_constraint(owner, con);
      /* targets have already been checked for this */
      check_targets = false;
    }
    else if (con->type == CONSTRAINT_TYPE_PIVOT) {
      bPivotConstraint *data = con->data;
  
      /* target doesn't have to exist, but if it is non-null, it must exist! */
      if (data->tar && BKE_object_exists_check(bmain, data->tar) == 0) {
        data->tar = NULL;
        con->flag |= CONSTRAINT_DISABLE;
      }
      else if (data->tar == owner) {
        if (!BKE_armature_find_bone_name(BKE_armature_from_object(owner), data->subtarget)) {
          con->flag |= CONSTRAINT_DISABLE;
        }
      }
  
      /* targets have already been checked for this */
      check_targets = false;
    }
    else if (con->type == CONSTRAINT_TYPE_ACTION) {
      bActionConstraint *data = con->data;
  
      /* validate action */
      if (data->act == NULL) {
        /* must have action */
        con->flag |= CONSTRAINT_DISABLE;
      }
      else if (data->act->idroot != ID_OB) {
        /* only object-rooted actions can be used */
        data->act = NULL;
        con->flag |= CONSTRAINT_DISABLE;
      }
  
      /* Skip target checking if we're not using it */
      if (data->flag & ACTCON_USE_EVAL_TIME) {
        check_targets = false;
      }
    }
    else if (con->type == CONSTRAINT_TYPE_FOLLOWPATH) {
      bFollowPathConstraint *data = con->data;
  
      /* don't allow track/up axes to be the same */
      if (data->upflag == data->trackflag) {
        con->flag |= CONSTRAINT_DISABLE;
      }
      if (data->upflag + 3 == data->trackflag) {
        con->flag |= CONSTRAINT_DISABLE;
      }
    }
    else if (con->type == CONSTRAINT_TYPE_TRACKTO) {
      bTrackToConstraint *data = con->data;
  
      /* don't allow track/up axes to be the same */
      if (data->reserved2 == data->reserved1) {
        con->flag |= CONSTRAINT_DISABLE;
      }
      if (data->reserved2 + 3 == data->reserved1) {
        con->flag |= CONSTRAINT_DISABLE;
      }
    }
    else if (con->type == CONSTRAINT_TYPE_LOCKTRACK) {
      bLockTrackConstraint *data = con->data;
  
      if (data->lockflag == data->trackflag) {
        con->flag |= CONSTRAINT_DISABLE;
      }
      if (data->lockflag + 3 == data->trackflag) {
        con->flag |= CONSTRAINT_DISABLE;
      }
    }
    else if (con->type == CONSTRAINT_TYPE_SPLINEIK) {
      bSplineIKConstraint *data = con->data;
  
      /* if the number of points does not match the amount required by the chain length,
       * free the points array and request a rebind...
       */
      if ((data->points == NULL) || (data->numpoints != data->chainlen + 1)) {
        /* free the points array */
        if (data->points) {
          MEM_freeN(data->points);
          data->points = NULL;
        }
  
        /* clear the bound flag, forcing a rebind next time this is evaluated */
        data->flag &= ~CONSTRAINT_SPLINEIK_BOUND;
      }
    }
    else if (con->type == CONSTRAINT_TYPE_FOLLOWTRACK) {
      bFollowTrackConstraint *data = con->data;
  
      if ((data->flag & CAMERASOLVER_ACTIVECLIP) == 0) {
        if (data->clip != NULL && data->track[0]) {
          MovieTracking *tracking = &data->clip->tracking;
          MovieTrackingObject *tracking_object;
  
          if (data->object[0]) {
            tracking_object = BKE_tracking_object_get_named(tracking, data->object);
          }
          else {
            tracking_object = BKE_tracking_object_get_camera(tracking);
          }
  
          if (!tracking_object) {
            con->flag |= CONSTRAINT_DISABLE;
          }
          else {
            if (!BKE_tracking_track_get_named(tracking, tracking_object, data->track)) {
              con->flag |= CONSTRAINT_DISABLE;
            }
          }
        }
        else {
          con->flag |= CONSTRAINT_DISABLE;
        }
      }
    }
    else if (con->type == CONSTRAINT_TYPE_CAMERASOLVER) {
      bCameraSolverConstraint *data = con->data;
  
      if ((data->flag & CAMERASOLVER_ACTIVECLIP) == 0 && (data->clip == NULL)) {
        con->flag |= CONSTRAINT_DISABLE;
      }
    }
    else if (con->type == CONSTRAINT_TYPE_OBJECTSOLVER) {
      bObjectSolverConstraint *data = con->data;
  
      if ((data->flag & CAMERASOLVER_ACTIVECLIP) == 0 && (data->clip == NULL)) {
        con->flag |= CONSTRAINT_DISABLE;
      }
    }
    else if (con->type == CONSTRAINT_TYPE_TRANSFORM_CACHE) {
      bTransformCacheConstraint *data = con->data;
  
      if ((data->cache_file == NULL) || (data->object_path[0] == '\0')) {
        con->flag |= CONSTRAINT_DISABLE;
      }
    }
  
    /* Check targets for constraints */
    if (check_targets && cti && cti->get_constraint_targets) {
      cti->get_constraint_targets(con, &targets);
  
      /* constraints with empty target list that actually require targets */
      if (!targets.first && ELEM(con->type, CONSTRAINT_TYPE_ARMATURE)) {
        con->flag |= CONSTRAINT_DISABLE;
      }
  
      /* disable and clear constraints targets that are incorrect */
      for (ct = targets.first; ct; ct = ct->next) {
        /* general validity checks (for those constraints that need this) */
        if (BKE_object_exists_check(bmain, ct->tar) == 0) {
          /* object doesn't exist, but constraint requires target */
          ct->tar = NULL;
          con->flag |= CONSTRAINT_DISABLE;
        }
        else if (ct->tar == owner) {
          if (type == CONSTRAINT_OBTYPE_BONE) {
            if (!BKE_armature_find_bone_name(BKE_armature_from_object(owner), ct->subtarget)) {
              /* bone must exist in armature... */
              /* TODO: clear subtarget? */
              con->flag |= CONSTRAINT_DISABLE;
            }
            else if (STREQ(pchan->name, ct->subtarget)) {
              /* cannot target self */
              ct->subtarget[0] = '\0';
              con->flag |= CONSTRAINT_DISABLE;
            }
          }
          else {
            /* cannot use self as target */
            ct->tar = NULL;
            con->flag |= CONSTRAINT_DISABLE;
          }
        }
  
        /* target checks for specific constraints */
        if (ELEM(con->type,
                 CONSTRAINT_TYPE_FOLLOWPATH,
                 CONSTRAINT_TYPE_CLAMPTO,
                 CONSTRAINT_TYPE_SPLINEIK)) {
          if (ct->tar) {
            /* The object type check is only needed here in case we have a placeholder
             * object assigned (because the library containing the curve is missing).
             *
             * In other cases it should be impossible to have a type mismatch.
             */
            if (ct->tar->type != OB_CURVE) {
              con->flag |= CONSTRAINT_DISABLE;
            }
            else {
              Curve *cu = ct->tar->data;
  
              /* auto-set 'Path' setting on curve so this works  */
              cu->flag |= CU_PATH;
            }
          }
        }
        else if (con->type == CONSTRAINT_TYPE_ARMATURE) {
          if (ct->tar) {
            /* The object type check is only needed here in case we have a placeholder
             * object assigned (because the library containing the armature is missing).
             *
             * In other cases it should be impossible to have a type mismatch.
             */
            if (ct->tar->type != OB_ARMATURE) {
              con->flag |= CONSTRAINT_DISABLE;
            }
            else if (!BKE_armature_find_bone_name(BKE_armature_from_object(ct->tar),
                                                  ct->subtarget)) {
              /* bone must exist in armature... */
              con->flag |= CONSTRAINT_DISABLE;
            }
          }
        }
      }
  
      /* free any temporary targets */
      if (cti->flush_constraint_targets) {
        cti->flush_constraint_targets(con, &targets, 0);
      }
    }
  }
  
  static int constraint_type_get(Object *owner, bPoseChannel *pchan)
  {
    int type;
    /* Check parents */
    if (pchan) {
      switch (owner->type) {
        case OB_ARMATURE:
          type = CONSTRAINT_OBTYPE_BONE;
          break;
        default:
          type = CONSTRAINT_OBTYPE_OBJECT;
          break;
      }
    }
    else {
      type = CONSTRAINT_OBTYPE_OBJECT;
    }
    return type;
  }
  
  /* checks validity of object pointers, and NULLs,
   * if Bone doesn't exist it sets the CONSTRAINT_DISABLE flag.
   */
  static void test_constraints(Main *bmain, Object *ob, bPoseChannel *pchan)
  {
    bConstraint *curcon;
    ListBase *conlist = NULL;
    int type;
  
    if (ob == NULL) {
      return;
    }
  
    type = constraint_type_get(ob, pchan);
  
    /* Get the constraint list for this object */
    switch (type) {
      case CONSTRAINT_OBTYPE_OBJECT:
        conlist = &ob->constraints;
        break;
      case CONSTRAINT_OBTYPE_BONE:
        conlist = &pchan->constraints;
        break;
    }
  
    /* Check all constraints - is constraint valid? */
    if (conlist) {
      for (curcon = conlist->first; curcon; curcon = curcon->next) {
        test_constraint(bmain, ob, pchan, curcon, type);
      }
    }
  }
  
  void object_test_constraints(Main *bmain, Object *ob)
  {
    if (ob->constraints.first) {
      test_constraints(bmain, ob, NULL);
    }
  
    if (ob->type == OB_ARMATURE && ob->pose) {
      bPoseChannel *pchan;
  
      for (pchan = ob->pose->chanbase.first; pchan; pchan = pchan->next) {
        if (pchan->constraints.first) {
          test_constraints(bmain, ob, pchan);
        }
      }
    }
  }
  
  static void object_test_constraint(Main *bmain, Object *ob, bConstraint *con)
  {
    if (ob->type == OB_ARMATURE && ob->pose) {
      if (BLI_findindex(&ob->constraints, con) != -1) {
        test_constraint(bmain, ob, NULL, con, CONSTRAINT_OBTYPE_OBJECT);
      }
      else {
        bPoseChannel *pchan;
        for (pchan = ob->pose->chanbase.first; pchan; pchan = pchan->next) {
          if (BLI_findindex(&pchan->constraints, con) != -1) {
            test_constraint(bmain, ob, pchan, con, CONSTRAINT_OBTYPE_BONE);
            break;
          }
        }
      }
    }
    else {
      test_constraint(bmain, ob, NULL, con, CONSTRAINT_OBTYPE_OBJECT);
    }
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Generic Functions for Operators Using Constraint Names and Data Context
   * \{ */
  
  #define EDIT_CONSTRAINT_OWNER_OBJECT 0
  #define EDIT_CONSTRAINT_OWNER_BONE 1
  
  static const EnumPropertyItem constraint_owner_items[] = {
      {EDIT_CONSTRAINT_OWNER_OBJECT,
       "OBJECT",
       0,
       "Object",
       "Edit a constraint on the active object"},
      {EDIT_CONSTRAINT_OWNER_BONE, "BONE", 0, "Bone", "Edit a constraint on the active bone"},
      {0, NULL, 0, NULL, NULL},
  };
  
  static bool edit_constraint_poll_generic(bContext *C,
                                           StructRNA *rna_type,
                                           const bool is_liboverride_allowed)
  {
    PointerRNA ptr = CTX_data_pointer_get_type(C, "constraint", rna_type);
    Object *ob = (ptr.owner_id) ? (Object *)ptr.owner_id : ED_object_active_context(C);
    bConstraint *con = ptr.data;
  
    if (!ob) {
      CTX_wm_operator_poll_msg_set(C, "Context missing active object");
      return false;
    }
  
    if (ID_IS_LINKED(ob) || (ptr.owner_id && ID_IS_LINKED(ptr.owner_id))) {
      CTX_wm_operator_poll_msg_set(C, "Cannot edit library data");
      return false;
    }
  
    if (ID_IS_OVERRIDE_LIBRARY(ob) && !is_liboverride_allowed) {
      if ((con == NULL) || (con->flag & CONSTRAINT_OVERRIDE_LIBRARY_LOCAL) == 0) {
        CTX_wm_operator_poll_msg_set(C, "Cannot edit constraints coming from library override");
        return false;
      }
    }
  
    return true;
  }
  
  static bool edit_constraint_poll(bContext *C)
  {
    return edit_constraint_poll_generic(C, &RNA_Constraint, false);
  }
  
  /* Used by operators performing actions allowed also on constraints from the overridden linked
   * object (not only from added 'local' ones). */
  static bool edit_constraint_liboverride_allowed_poll(bContext *C)
  {
    return edit_constraint_poll_generic(C, &RNA_Constraint, true);
  }
  
  static void edit_constraint_properties(wmOperatorType *ot)
  {
    PropertyRNA *prop;
    prop = RNA_def_string(
        ot->srna, "constraint", NULL, MAX_NAME, "Constraint", "Name of the constraint to edit");
    RNA_def_property_flag(prop, PROP_HIDDEN);
    prop = RNA_def_enum(
        ot->srna, "owner", constraint_owner_items, 0, "Owner", "The owner of this constraint");
    RNA_def_property_flag(prop, PROP_HIDDEN);
  }
  
  static void edit_constraint_report_property(wmOperatorType *ot)
  {
    PropertyRNA *prop = RNA_def_boolean(
        ot->srna, "report", false, "Report", "Create a notification after the operation");
    RNA_def_property_flag(prop, PROP_HIDDEN | PROP_SKIP_SAVE);
  }
  
  static bool edit_constraint_invoke_properties(bContext *C,
                                                wmOperator *op,
                                                const wmEvent *event,
                                                int *r_retval)
  {
    PointerRNA ptr = CTX_data_pointer_get_type(C, "constraint", &RNA_Constraint);
    Object *ob = (ptr.owner_id) ? (Object *)ptr.owner_id : ED_object_active_context(C);
    bConstraint *con;
    ListBase *list;
  
    if (RNA_struct_property_is_set(op->ptr, "constraint") &&
        RNA_struct_property_is_set(op->ptr, "owner")) {
      return true;
    }
  
    if (ptr.data) {
      con = ptr.data;
      RNA_string_set(op->ptr, "constraint", con->name);
  
      list = ED_object_constraint_list_from_constraint(ob, con, NULL);
  
      if (&ob->constraints == list) {
        RNA_enum_set(op->ptr, "owner", EDIT_CONSTRAINT_OWNER_OBJECT);
      }
      else {
        RNA_enum_set(op->ptr, "owner", EDIT_CONSTRAINT_OWNER_BONE);
      }
  
      return true;
    }
  
    /* Check the custom data of panels under the mouse for a modifier. */
    if (event != NULL) {
      PointerRNA *panel_ptr = UI_region_panel_custom_data_under_cursor(C, event);
  
      if (!(panel_ptr == NULL || RNA_pointer_is_null(panel_ptr))) {
        if (RNA_struct_is_a(panel_ptr->type, &RNA_Constraint)) {
          con = panel_ptr->data;
          RNA_string_set(op->ptr, "constraint", con->name);
          list = ED_object_constraint_list_from_constraint(ob, con, NULL);
          RNA_enum_set(op->ptr,
                       "owner",
                       (&ob->constraints == list) ? EDIT_CONSTRAINT_OWNER_OBJECT :
                                                    EDIT_CONSTRAINT_OWNER_BONE);
  
          return true;
        }
  
        BLI_assert(r_retval != NULL); /* We need the return value in this case. */
        if (r_retval != NULL) {
          *r_retval = (OPERATOR_PASS_THROUGH | OPERATOR_CANCELLED);
        }
        return false;
      }
    }
  
    return false;
  }
  
  static bConstraint *edit_constraint_property_get(bContext *C, wmOperator *op, Object *ob, int type)
  {
    char constraint_name[MAX_NAME];
    int owner = RNA_enum_get(op->ptr, "owner");
    bConstraint *con;
    ListBase *list = NULL;
  
    RNA_string_get(op->ptr, "constraint", constraint_name);
  
    if (owner == EDIT_CONSTRAINT_OWNER_BONE) {
      list = ED_object_pose_constraint_list(C);
    }
    else {
      list = &ob->constraints;
    }
  
    con = BKE_constraints_find_name(list, constraint_name);
  #if 0
    if (G.debug & G_DEBUG) {
      printf("constraint found = %p, %s\n", (void *)con, (con) ? con->name : "<Not found>");
    }
  #endif
  
    if (con && (type != 0) && (con->type != type)) {
      con = NULL;
    }
  
    return con;
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Stretch-To/Limit-Distance Constraint (Reset Original Length Operator)
   *
   * For Stretch-To & Limit-Distance constraints.
   * \{ */
  
  static int stretchto_reset_exec(bContext *C, wmOperator *op)
  {
    Main *bmain = CTX_data_main(C);
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, CONSTRAINT_TYPE_STRETCHTO);
    bStretchToConstraint *data = (con) ? (bStretchToConstraint *)con->data : NULL;
  
    /* despite 3 layers of checks, we may still not be able to find a constraint */
    if (data == NULL) {
      return OPERATOR_CANCELLED;
    }
  
    /* just set original length to 0.0, which will cause a reset on next recalc */
    data->orglength = 0.0f;
    ED_object_constraint_update(bmain, ob);
  
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, NULL);
    return OPERATOR_FINISHED;
  }
  
  static int stretchto_reset_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
  {
    if (edit_constraint_invoke_properties(C, op, NULL, NULL)) {
      return stretchto_reset_exec(C, op);
    }
    return OPERATOR_CANCELLED;
  }
  
  void CONSTRAINT_OT_stretchto_reset(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Reset Original Length";
    ot->idname = "CONSTRAINT_OT_stretchto_reset";
    ot->description = "Reset original length of bone for Stretch To Constraint";
  
    /* callbacks */
    ot->invoke = stretchto_reset_invoke;
    ot->exec = stretchto_reset_exec;
    ot->poll = edit_constraint_liboverride_allowed_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    edit_constraint_properties(ot);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Distance Constraint (Reset Operator)
   *
   * For Limit-Distance constraint.
   * \{ */
  
  static int limitdistance_reset_exec(bContext *C, wmOperator *op)
  {
    Main *bmain = CTX_data_main(C);
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, CONSTRAINT_TYPE_DISTLIMIT);
    bDistLimitConstraint *data = (con) ? (bDistLimitConstraint *)con->data : NULL;
  
    /* despite 3 layers of checks, we may still not be able to find a constraint */
    if (data == NULL) {
      return OPERATOR_CANCELLED;
    }
  
    /* just set original length to 0.0, which will cause a reset on next recalc */
    data->dist = 0.0f;
    ED_object_constraint_update(bmain, ob);
  
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, NULL);
    return OPERATOR_FINISHED;
  }
  
  static int limitdistance_reset_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
  {
    if (edit_constraint_invoke_properties(C, op, NULL, NULL)) {
      return limitdistance_reset_exec(C, op);
    }
    return OPERATOR_CANCELLED;
  }
  
  void CONSTRAINT_OT_limitdistance_reset(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Reset Distance";
    ot->idname = "CONSTRAINT_OT_limitdistance_reset";
    ot->description = "Reset limiting distance for Limit Distance Constraint";
  
    /* callbacks */
    ot->invoke = limitdistance_reset_invoke;
    ot->exec = limitdistance_reset_exec;
    ot->poll = edit_constraint_liboverride_allowed_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    edit_constraint_properties(ot);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Child-Of Constraint (Set Inverse Operator)
   * \{ */
  
  /* Force evaluation so that the 'set inverse' flag is handled.
   * No-op when the constraint is enabled, as in such cases the evaluation will happen anyway.
   */
  static void force_evaluation_if_constraint_disabled(bContext *C, Object *ob, bConstraint *con)
  {
    if ((con->flag & (CONSTRAINT_DISABLE | CONSTRAINT_OFF)) == 0) {
      return;
    }
  
    Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
    Scene *scene = DEG_get_evaluated_scene(depsgraph);
  
    short flag_backup = con->flag;
    con->flag &= ~(CONSTRAINT_DISABLE | CONSTRAINT_OFF);
    BKE_object_eval_constraints(depsgraph, scene, ob);
    con->flag = flag_backup;
  }
  
  /* ChildOf Constraint - set inverse callback */
  static int childof_set_inverse_exec(bContext *C, wmOperator *op)
  {
    Main *bmain = CTX_data_main(C);
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, CONSTRAINT_TYPE_CHILDOF);
    bChildOfConstraint *data = (con) ? (bChildOfConstraint *)con->data : NULL;
  
    /* despite 3 layers of checks, we may still not be able to find a constraint */
    if (data == NULL) {
      printf("DEBUG: Child-Of Set Inverse - object = '%s'\n", (ob) ? ob->id.name + 2 : "<None>");
      BKE_report(op->reports, RPT_ERROR, "Could not find constraint data for Child-Of Set Inverse");
      return OPERATOR_CANCELLED;
    }
  
    /* Set a flag to request recalculation on next update. */
    data->flag |= CHILDOF_SET_INVERSE;
  
    /* Force constraint to run, it will perform the recalculation. */
    force_evaluation_if_constraint_disabled(C, ob, con);
  
    ED_object_constraint_update(bmain, ob);
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, ob);
  
    return OPERATOR_FINISHED;
  }
  
  static int childof_set_inverse_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
  {
    if (edit_constraint_invoke_properties(C, op, NULL, NULL)) {
      return childof_set_inverse_exec(C, op);
    }
    return OPERATOR_CANCELLED;
  }
  
  void CONSTRAINT_OT_childof_set_inverse(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Set Inverse";
    ot->idname = "CONSTRAINT_OT_childof_set_inverse";
    ot->description = "Set inverse correction for ChildOf constraint";
  
    /* callbacks */
    ot->invoke = childof_set_inverse_invoke;
    ot->exec = childof_set_inverse_exec;
    ot->poll = edit_constraint_liboverride_allowed_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    edit_constraint_properties(ot);
  }
  
  /* ChildOf Constraint - clear inverse callback */
  static int childof_clear_inverse_exec(bContext *C, wmOperator *op)
  {
    Main *bmain = CTX_data_main(C);
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, CONSTRAINT_TYPE_CHILDOF);
    bChildOfConstraint *data = (con) ? (bChildOfConstraint *)con->data : NULL;
  
    if (data == NULL) {
      BKE_report(op->reports, RPT_ERROR, "Child Of constraint not found");
      return OPERATOR_CANCELLED;
    }
  
    /* simply clear the matrix */
    unit_m4(data->invmat);
  
    ED_object_constraint_update(bmain, ob);
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, ob);
  
    return OPERATOR_FINISHED;
  }
  
  static int childof_clear_inverse_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
  {
    if (edit_constraint_invoke_properties(C, op, NULL, NULL)) {
      return childof_clear_inverse_exec(C, op);
    }
    return OPERATOR_CANCELLED;
  }
  
  void CONSTRAINT_OT_childof_clear_inverse(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Clear Inverse";
    ot->idname = "CONSTRAINT_OT_childof_clear_inverse";
    ot->description = "Clear inverse correction for ChildOf constraint";
  
    /* callbacks */
    ot->invoke = childof_clear_inverse_invoke;
    ot->exec = childof_clear_inverse_exec;
    ot->poll = edit_constraint_liboverride_allowed_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    edit_constraint_properties(ot);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Follow Path Constraint (Auto Animate Path Operator)
   * \{ */
  
  static int followpath_path_animate_exec(bContext *C, wmOperator *op)
  {
    Main *bmain = CTX_data_main(C);
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, CONSTRAINT_TYPE_FOLLOWPATH);
    bFollowPathConstraint *data = (con) ? (bFollowPathConstraint *)con->data : NULL;
  
    bAction *act = NULL;
    FCurve *fcu = NULL;
    int sfra = RNA_int_get(op->ptr, "frame_start");
    int len = RNA_int_get(op->ptr, "length");
    float standardRange = 1.0;
  
    /* nearly impossible sanity check */
    if (data == NULL) {
      BKE_report(op->reports, RPT_ERROR, "Follow Path constraint not found");
      return OPERATOR_CANCELLED;
    }
  
    /* add F-Curve as appropriate */
    if (data->tar) {
      Curve *cu = (Curve *)data->tar->data;
  
      if (ELEM(NULL, cu->adt, cu->adt->action) ||
          (BKE_fcurve_find(&cu->adt->action->curves, "eval_time", 0) == NULL)) {
        /* create F-Curve for path animation */
        act = ED_id_action_ensure(bmain, &cu->id);
        fcu = ED_action_fcurve_ensure(bmain, act, NULL, NULL, "eval_time", 0);
  
        /* standard vertical range - 1:1 = 100 frames */
        standardRange = 100.0f;
      }
      else {
        /* path anim exists already - abort for now as this may well be what was intended */
        BKE_report(op->reports, RPT_WARNING, "Path is already animated");
        return OPERATOR_CANCELLED;
      }
    }
    else {
      /* animate constraint's "fixed offset" */
      PointerRNA ptr;
      PropertyRNA *prop;
      char *path;
  
      /* get RNA pointer to constraint's "offset_factor" property - to build RNA path */
      RNA_pointer_create(&ob->id, &RNA_FollowPathConstraint, con, &ptr);
      prop = RNA_struct_find_property(&ptr, "offset_factor");
  
      path = RNA_path_from_ID_to_property(&ptr, prop);
  
      /* create F-Curve for constraint */
      act = ED_id_action_ensure(bmain, &ob->id);
      fcu = ED_action_fcurve_ensure(bmain, act, NULL, NULL, path, 0);
  
      /* standard vertical range - 0.0 to 1.0 */
      standardRange = 1.0f;
  
      /* enable "Use Fixed Position" so that animating this has effect */
      data->followflag |= FOLLOWPATH_STATIC;
  
      /* path needs to be freed */
      if (path) {
        MEM_freeN(path);
      }
    }
  
    /* setup dummy 'generator' modifier here to get 1-1 correspondence still working
     * and define basic slope of this curve based on the properties
     */
    if (!fcu->bezt && !fcu->fpt && !fcu->modifiers.first) {
      FModifier *fcm = add_fmodifier(&fcu->modifiers, FMODIFIER_TYPE_GENERATOR, fcu);
      FMod_Generator *gen = fcm->data;
  
      /* Assume that we have the following equation:
       *     y = Ax + B
       *         1    0       <-- coefficients array indices
       */
      float A = standardRange / (float)(len);
      float B = (float)(-sfra) * A;
  
      gen->coefficients[1] = A;
      gen->coefficients[0] = B;
    }
  
    /* updates... */
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, ob);
    return OPERATOR_FINISHED;
  }
  
  static int followpath_path_animate_invoke(bContext *C,
                                            wmOperator *op,
                                            const wmEvent *UNUSED(event))
  {
    /* hook up invoke properties for figuring out which constraint we're dealing with */
    if (edit_constraint_invoke_properties(C, op, NULL, NULL)) {
      return followpath_path_animate_exec(C, op);
    }
    return OPERATOR_CANCELLED;
  }
  
  void CONSTRAINT_OT_followpath_path_animate(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Auto Animate Path";
    ot->idname = "CONSTRAINT_OT_followpath_path_animate";
    ot->description =
        "Add default animation for path used by constraint if it isn't animated already";
  
    /* callbacks */
    ot->invoke = followpath_path_animate_invoke;
    ot->exec = followpath_path_animate_exec;
    ot->poll = edit_constraint_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* props */
    edit_constraint_properties(ot);
    RNA_def_int(ot->srna,
                "frame_start",
                1,
                MINAFRAME,
                MAXFRAME,
                "Start Frame",
                "First frame of path animation",
                MINAFRAME,
                MAXFRAME);
    RNA_def_int(ot->srna,
                "length",
                100,
                0,
                MAXFRAME,
                "Length",
                "Number of frames that path animation should take",
                0,
                MAXFRAME);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Object Solver Constraint (Set Inverse Operator)
   * \{ */
  
  static int objectsolver_set_inverse_exec(bContext *C, wmOperator *op)
  {
    Main *bmain = CTX_data_main(C);
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, CONSTRAINT_TYPE_OBJECTSOLVER);
    bObjectSolverConstraint *data = (con) ? (bObjectSolverConstraint *)con->data : NULL;
  
    /* despite 3 layers of checks, we may still not be able to find a constraint */
    if (data == NULL) {
      printf("DEBUG: ObjectSolver Set Inverse - object = '%s'\n", (ob) ? ob->id.name + 2 : "<None>");
      BKE_report(
          op->reports, RPT_ERROR, "Could not find constraint data for ObjectSolver Set Inverse");
      return OPERATOR_CANCELLED;
    }
  
    /* Set a flag to request recalculation on next update. */
    data->flag |= OBJECTSOLVER_SET_INVERSE;
  
    /* Force constraint to run, it will perform the recalculation. */
    force_evaluation_if_constraint_disabled(C, ob, con);
  
    ED_object_constraint_update(bmain, ob);
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, ob);
  
    return OPERATOR_FINISHED;
  }
  
  static int objectsolver_set_inverse_invoke(bContext *C,
                                             wmOperator *op,
                                             const wmEvent *UNUSED(event))
  {
    if (edit_constraint_invoke_properties(C, op, NULL, NULL)) {
      return objectsolver_set_inverse_exec(C, op);
    }
    return OPERATOR_CANCELLED;
  }
  
  void CONSTRAINT_OT_objectsolver_set_inverse(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Set Inverse";
    ot->idname = "CONSTRAINT_OT_objectsolver_set_inverse";
    ot->description = "Set inverse correction for ObjectSolver constraint";
  
    /* callbacks */
    ot->invoke = objectsolver_set_inverse_invoke;
    ot->exec = objectsolver_set_inverse_exec;
    ot->poll = edit_constraint_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    edit_constraint_properties(ot);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Object Solver Constraint (Clear Inverse Operator)
   * \{ */
  
  static int objectsolver_clear_inverse_exec(bContext *C, wmOperator *op)
  {
    Main *bmain = CTX_data_main(C);
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, CONSTRAINT_TYPE_OBJECTSOLVER);
    bObjectSolverConstraint *data = (con) ? (bObjectSolverConstraint *)con->data : NULL;
  
    if (data == NULL) {
      BKE_report(op->reports, RPT_ERROR, "Child Of constraint not found");
      return OPERATOR_CANCELLED;
    }
  
    /* simply clear the matrix */
    unit_m4(data->invmat);
  
    ED_object_constraint_update(bmain, ob);
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, ob);
  
    return OPERATOR_FINISHED;
  }
  
  static int objectsolver_clear_inverse_invoke(bContext *C,
                                               wmOperator *op,
                                               const wmEvent *UNUSED(event))
  {
    if (edit_constraint_invoke_properties(C, op, NULL, NULL)) {
      return objectsolver_clear_inverse_exec(C, op);
    }
    return OPERATOR_CANCELLED;
  }
  
  void CONSTRAINT_OT_objectsolver_clear_inverse(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Clear Inverse";
    ot->idname = "CONSTRAINT_OT_objectsolver_clear_inverse";
    ot->description = "Clear inverse correction for ObjectSolver constraint";
  
    /* callbacks */
    ot->invoke = objectsolver_clear_inverse_invoke;
    ot->exec = objectsolver_clear_inverse_exec;
    ot->poll = edit_constraint_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    edit_constraint_properties(ot);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Constraint Management Utilities
   * \{ */
  
  void ED_object_constraint_active_set(Object *ob, bConstraint *con)
  {
    ListBase *lb = ED_object_constraint_list_from_constraint(ob, con, NULL);
  
    /* lets be nice and escape if its active already */
    /* NOTE: this assumes that the stack doesn't have other active ones set... */
    if ((lb && con) && (con->flag & CONSTRAINT_ACTIVE)) {
      return;
    }
  
    BKE_constraints_active_set(lb, con);
  }
  
  void ED_object_constraint_update(Main *bmain, Object *ob)
  {
    if (ob->pose) {
      BKE_pose_update_constraint_flags(ob->pose);
    }
  
    object_test_constraints(bmain, ob);
  
    if (ob->type == OB_ARMATURE) {
      DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY | ID_RECALC_TRANSFORM);
    }
    else {
      DEG_id_tag_update(&ob->id, ID_RECALC_TRANSFORM);
    }
  }
  
  static void object_pose_tag_update(Main *bmain, Object *ob)
  {
    BKE_pose_tag_recalc(bmain, ob->pose); /* Checks & sort pose channels. */
    if (ob->proxy && ob->adt) {
      /* We need to make use of ugly #POSE_ANIMATION_WORKAROUND here too,
       * else anim data are not reloaded after calling `BKE_pose_rebuild()`,
       * which causes T43872.
       * Note that this is a bit wide here, since we cannot be sure whether there are some locked
       * proxy bones or not.
       * XXX Temp hack until new depsgraph hopefully solves this. */
      DEG_id_tag_update(&ob->id, ID_RECALC_ANIMATION);
    }
  }
  
  void ED_object_constraint_dependency_update(Main *bmain, Object *ob)
  {
    ED_object_constraint_update(bmain, ob);
  
    if (ob->pose) {
      object_pose_tag_update(bmain, ob);
    }
    DEG_relations_tag_update(bmain);
  }
  
  void ED_object_constraint_tag_update(Main *bmain, Object *ob, bConstraint *con)
  {
    if (ob->pose) {
      BKE_pose_tag_update_constraint_flags(ob->pose);
    }
  
    if (con) {
      object_test_constraint(bmain, ob, con);
    }
  
    if (ob->type == OB_ARMATURE) {
      DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY | ID_RECALC_TRANSFORM);
    }
    else {
      DEG_id_tag_update(&ob->id, ID_RECALC_TRANSFORM);
    }
  
    /* Do Copy-on-Write tag here too, otherwise constraint
     * influence/mute buttons in UI have no effect
     */
    DEG_id_tag_update(&ob->id, ID_RECALC_COPY_ON_WRITE);
  }
  
  void ED_object_constraint_dependency_tag_update(Main *bmain, Object *ob, bConstraint *con)
  {
    ED_object_constraint_tag_update(bmain, ob, con);
  
    if (ob->pose) {
      object_pose_tag_update(bmain, ob);
    }
    DEG_relations_tag_update(bmain);
  }
  
  bool ED_object_constraint_move_to_index(Object *ob, bConstraint *con, const int index)
  {
    BLI_assert(con != NULL);
    BLI_assert(index >= 0);
  
    ListBase *conlist = ED_object_constraint_list_from_constraint(ob, con, NULL);
    int current_index = BLI_findindex(conlist, con);
    BLI_assert(current_index >= 0);
  
    BLI_listbase_link_move(conlist, con, index - current_index);
  
    WM_main_add_notifier(NC_OBJECT | ND_CONSTRAINT, ob);
  
    return true;
  }
  
  void ED_object_constraint_link(Main *bmain, Object *ob_dst, ListBase *dst, ListBase *src)
  {
    BKE_constraints_free(dst);
    BKE_constraints_copy(dst, src, true);
    LISTBASE_FOREACH (bConstraint *, con, dst) {
      ED_object_constraint_dependency_tag_update(bmain, ob_dst, con);
    }
    WM_main_add_notifier(NC_OBJECT | ND_CONSTRAINT | NA_ADDED, NULL);
  }
  
  void ED_object_constraint_copy_for_object(Main *bmain, Object *ob_dst, bConstraint *con)
  {
    BKE_constraint_copy_for_object(ob_dst, con);
    ED_object_constraint_dependency_tag_update(bmain, ob_dst, con);
    WM_main_add_notifier(NC_OBJECT | ND_CONSTRAINT | NA_ADDED, ob_dst);
  }
  
  void ED_object_constraint_copy_for_pose(Main *bmain,
                                          Object *ob_dst,
                                          bPoseChannel *pchan,
                                          bConstraint *con)
  {
    BKE_constraint_copy_for_pose(ob_dst, pchan, con);
    ED_object_constraint_dependency_tag_update(bmain, ob_dst, con);
    WM_main_add_notifier(NC_OBJECT | ND_CONSTRAINT | NA_ADDED, ob_dst);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Delete Constraint Operator
   * \{ */
  
  static int constraint_delete_exec(bContext *C, wmOperator *op)
  {
    Main *bmain = CTX_data_main(C);
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, 0);
    ListBase *lb = ED_object_constraint_list_from_constraint(ob, con, NULL);
  
    /* Store name temporarily for report. */
    char name[MAX_NAME];
    strcpy(name, con->name);
  
    /* free the constraint */
    if (BKE_constraint_remove_ex(lb, ob, con, true)) {
      /* there's no active constraint now, so make sure this is the case */
      BKE_constraints_active_set(&ob->constraints, NULL);
      /* needed to set the flags on posebones correctly */
      ED_object_constraint_update(bmain, ob);
  
      /* relations */
      DEG_relations_tag_update(CTX_data_main(C));
  
      /* notifiers */
      WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT | NA_REMOVED, ob);
  
      if (RNA_boolean_get(op->ptr, "report")) {
        BKE_reportf(op->reports, RPT_INFO, "Removed constraint: %s", name);
      }
  
      return OPERATOR_FINISHED;
    }
    /* couldn't remove due to some invalid data */
    return OPERATOR_CANCELLED;
  }
  
  static int constraint_delete_invoke(bContext *C, wmOperator *op, const wmEvent *event)
  {
    int retval;
    if (edit_constraint_invoke_properties(C, op, event, &retval)) {
      return constraint_delete_exec(C, op);
    }
    return OPERATOR_CANCELLED;
  }
  
  void CONSTRAINT_OT_delete(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Delete Constraint";
    ot->idname = "CONSTRAINT_OT_delete";
    ot->description = "Remove constraint from constraint stack";
  
    /* callbacks */
    ot->invoke = constraint_delete_invoke;
    ot->exec = constraint_delete_exec;
    ot->poll = edit_constraint_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
    edit_constraint_properties(ot);
    edit_constraint_report_property(ot);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Move Down Constraint Operator
   * \{ */
  
  static int constraint_move_down_exec(bContext *C, wmOperator *op)
  {
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, 0);
  
    if (con && con->next) {
      ListBase *conlist = ED_object_constraint_list_from_constraint(ob, con, NULL);
      bConstraint *nextCon = con->next;
  
      /* insert the nominated constraint after the one that used to be after it */
      BLI_remlink(conlist, con);
      BLI_insertlinkafter(conlist, nextCon, con);
  
      WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, ob);
  
      return OPERATOR_FINISHED;
    }
  
    return OPERATOR_CANCELLED;
  }
  
  static int constraint_move_down_invoke(bContext *C, wmOperator *op, const wmEvent *event)
  {
    int retval;
    if (edit_constraint_invoke_properties(C, op, event, &retval)) {
      return constraint_move_down_exec(C, op);
    }
    return retval;
  }
  
  void CONSTRAINT_OT_move_down(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Move Constraint Down";
    ot->idname = "CONSTRAINT_OT_move_down";
    ot->description = "Move constraint down in constraint stack";
  
    /* callbacks */
    ot->invoke = constraint_move_down_invoke;
    ot->exec = constraint_move_down_exec;
    ot->poll = edit_constraint_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    edit_constraint_properties(ot);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Move Up Constraint Operator
   * \{ */
  
  static int constraint_move_up_exec(bContext *C, wmOperator *op)
  {
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, 0);
  
    if (con && con->prev) {
      ListBase *conlist = ED_object_constraint_list_from_constraint(ob, con, NULL);
      bConstraint *prevCon = con->prev;
  
      /* insert the nominated constraint before the one that used to be before it */
      BLI_remlink(conlist, con);
      BLI_insertlinkbefore(conlist, prevCon, con);
  
      WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, ob);
  
      return OPERATOR_FINISHED;
    }
  
    return OPERATOR_CANCELLED;
  }
  
  static int constraint_move_up_invoke(bContext *C, wmOperator *op, const wmEvent *event)
  {
    int retval;
    if (edit_constraint_invoke_properties(C, op, event, &retval)) {
      return constraint_move_up_exec(C, op);
    }
    return retval;
  }
  
  void CONSTRAINT_OT_move_up(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Move Constraint Up";
    ot->idname = "CONSTRAINT_OT_move_up";
    ot->description = "Move constraint up in constraint stack";
  
    /* callbacks */
    ot->exec = constraint_move_up_exec;
    ot->invoke = constraint_move_up_invoke;
    ot->poll = edit_constraint_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
    edit_constraint_properties(ot);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Move Constraint To Index Operator
   * \{ */
  
  static int constraint_move_to_index_exec(bContext *C, wmOperator *op)
  {
    Object *ob = ED_object_active_context(C);
    bConstraint *con = edit_constraint_property_get(C, op, ob, 0);
  
    int new_index = RNA_int_get(op->ptr, "index");
    if (new_index < 0) {
      new_index = 0;
    }
  
    if (con) {
      ED_object_constraint_move_to_index(ob, con, new_index);
  
      return OPERATOR_FINISHED;
    }
  
    return OPERATOR_CANCELLED;
  }
  
  static int constraint_move_to_index_invoke(bContext *C, wmOperator *op, const wmEvent *event)
  {
    int retval;
    if (edit_constraint_invoke_properties(C, op, event, &retval)) {
      return constraint_move_to_index_exec(C, op);
    }
    return retval;
  }
  
  void CONSTRAINT_OT_move_to_index(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Move Constraint To Index";
    ot->idname = "CONSTRAINT_OT_move_to_index";
    ot->description =
        "Change the constraint's position in the list so it evaluates after the set number of "
        "others";
  
    /* callbacks */
    ot->exec = constraint_move_to_index_exec;
    ot->invoke = constraint_move_to_index_invoke;
    ot->poll = edit_constraint_poll;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
    edit_constraint_properties(ot);
    RNA_def_int(ot->srna,
                "index",
                0,
                0,
                INT_MAX,
                "Index",
                "The index to move the constraint to",
                0,
                INT_MAX);
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Clear Pose Constraints Operator
   * \{ */
  
  static int pose_constraints_clear_exec(bContext *C, wmOperator *UNUSED(op))
  {
    Main *bmain = CTX_data_main(C);
    Object *prev_ob = NULL;
  
    /* free constraints for all selected bones */
    CTX_DATA_BEGIN_WITH_ID (C, bPoseChannel *, pchan, selected_pose_bones, Object *, ob) {
      BKE_constraints_free(&pchan->constraints);
      pchan->constflag &= ~(PCHAN_HAS_IK | PCHAN_HAS_SPLINEIK | PCHAN_HAS_CONST);
  
      if (prev_ob != ob) {
        DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
        WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT | NA_REMOVED, ob);
        prev_ob = ob;
      }
    }
    CTX_DATA_END;
  
    /* force depsgraph to get recalculated since relationships removed */
    DEG_relations_tag_update(bmain);
  
    /* note, calling BIK_clear_data() isn't needed here */
  
    return OPERATOR_FINISHED;
  }
  
  void POSE_OT_constraints_clear(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Clear Pose Constraints";
    ot->idname = "POSE_OT_constraints_clear";
    ot->description = "Clear all the constraints for the selected bones";
  
    /* callbacks */
    ot->exec = pose_constraints_clear_exec;
    ot->poll = ED_operator_posemode_exclusive; /* XXX - do we want to ensure there are selected
                                                * bones too? */
  }
  
  static int object_constraints_clear_exec(bContext *C, wmOperator *UNUSED(op))
  {
    Main *bmain = CTX_data_main(C);
  
    /* do freeing */
    CTX_DATA_BEGIN (C, Object *, ob, selected_editable_objects) {
      BKE_constraints_free(&ob->constraints);
      DEG_id_tag_update(&ob->id, ID_RECALC_TRANSFORM);
    }
    CTX_DATA_END;
  
    /* force depsgraph to get recalculated since relationships removed */
    DEG_relations_tag_update(bmain);
  
    /* do updates */
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT | NA_REMOVED, NULL);
  
    return OPERATOR_FINISHED;
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Clear Object Constraints Operator
   * \{ */
  
  void OBJECT_OT_constraints_clear(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Clear Object Constraints";
    ot->idname = "OBJECT_OT_constraints_clear";
    ot->description = "Clear all the constraints for the active Object only";
  
    /* callbacks */
    ot->exec = object_constraints_clear_exec;
    ot->poll = ED_operator_object_active_local_editable;
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Copy Pose Constraints Operator
   * \{ */
  
  static int pose_constraint_copy_exec(bContext *C, wmOperator *op)
  {
    Main *bmain = CTX_data_main(C);
    bPoseChannel *pchan = CTX_data_active_pose_bone(C);
  
    /* don't do anything if bone doesn't exist or doesn't have any constraints */
    if (ELEM(NULL, pchan, pchan->constraints.first)) {
      BKE_report(op->reports, RPT_ERROR, "No active bone with constraints for copying");
      return OPERATOR_CANCELLED;
    }
  
    Object *prev_ob = NULL;
  
    /* copy all constraints from active posebone to all selected posebones */
    CTX_DATA_BEGIN_WITH_ID (C, bPoseChannel *, chan, selected_pose_bones, Object *, ob) {
      /* if we're not handling the object we're copying from, copy all constraints over */
      if (pchan != chan) {
        BKE_constraints_copy(&chan->constraints, &pchan->constraints, true);
        /* update flags (need to add here, not just copy) */
        chan->constflag |= pchan->constflag;
  
        if (prev_ob != ob) {
          BKE_pose_tag_recalc(bmain, ob->pose);
          DEG_id_tag_update((ID *)ob, ID_RECALC_GEOMETRY);
          prev_ob = ob;
        }
      }
    }
    CTX_DATA_END;
  
    /* force depsgraph to get recalculated since new relationships added */
    DEG_relations_tag_update(bmain);
  
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT, NULL);
  
    return OPERATOR_FINISHED;
  }
  
  void POSE_OT_constraints_copy(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Copy Constraints to Selected Bones";
    ot->idname = "POSE_OT_constraints_copy";
    ot->description = "Copy constraints to other selected bones";
  
    /* api callbacks */
    ot->exec = pose_constraint_copy_exec;
    ot->poll = ED_operator_posemode_exclusive;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Copy Object Constraints Operator
   * \{ */
  
  static int object_constraint_copy_exec(bContext *C, wmOperator *UNUSED(op))
  {
    Main *bmain = CTX_data_main(C);
    Object *obact = ED_object_active_context(C);
  
    /* copy all constraints from active object to all selected objects */
    CTX_DATA_BEGIN (C, Object *, ob, selected_editable_objects) {
      /* if we're not handling the object we're copying from, copy all constraints over */
      if (obact != ob) {
        BKE_constraints_copy(&ob->constraints, &obact->constraints, true);
        DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY | ID_RECALC_TRANSFORM);
      }
    }
    CTX_DATA_END;
  
    /* force depsgraph to get recalculated since new relationships added */
    DEG_relations_tag_update(bmain);
  
    /* notifiers for updates */
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT | NA_ADDED, NULL);
  
    return OPERATOR_FINISHED;
  }
  
  void OBJECT_OT_constraints_copy(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Copy Constraints to Selected Objects";
    ot->idname = "OBJECT_OT_constraints_copy";
    ot->description = "Copy constraints to other selected objects";
  
    /* api callbacks */
    ot->exec = object_constraint_copy_exec;
    ot->poll = ED_operator_object_active_editable;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Add Constraints Operator
   * \{ */
  
  /* get the Object and/or PoseChannel to use as target */
  static bool get_new_constraint_target(
      bContext *C, int con_type, Object **tar_ob, bPoseChannel **tar_pchan, bool add)
  {
    Object *obact = ED_object_active_context(C);
    bPoseChannel *pchanact = BKE_pose_channel_active(obact);
    bool only_curve = false, only_mesh = false, only_ob = false;
    bool found = false;
  
    /* clear tar_ob and tar_pchan fields before use
     * - assume for now that both always exist...
     */
    *tar_ob = NULL;
    *tar_pchan = NULL;
  
    /* check if constraint type doesn't requires a target
     * - if so, no need to get any targets
     */
    switch (con_type) {
      /* no-target constraints --------------------------- */
      /* null constraint - shouldn't even be added! */
      case CONSTRAINT_TYPE_NULL:
      /* limit constraints - no targets needed */
      case CONSTRAINT_TYPE_LOCLIMIT:
      case CONSTRAINT_TYPE_ROTLIMIT:
      case CONSTRAINT_TYPE_SIZELIMIT:
      case CONSTRAINT_TYPE_SAMEVOL:
        return false;
  
      /* restricted target-type constraints -------------- */
      /* NOTE: for these, we cannot try to add a target object if no valid ones are found,
       * since that doesn't work */
      /* curve-based constraints - set the only_curve and only_ob flags */
      case CONSTRAINT_TYPE_CLAMPTO:
      case CONSTRAINT_TYPE_FOLLOWPATH:
      case CONSTRAINT_TYPE_SPLINEIK:
        only_curve = true;
        only_ob = true;
        add = false;
        break;
  
      /* mesh only? */
      case CONSTRAINT_TYPE_SHRINKWRAP:
        only_mesh = true;
        only_ob = true;
        add = false;
        break;
    }
  
    /* if the active Object is Armature, and we can search for bones, do so... */
    if ((obact->type == OB_ARMATURE) && (only_ob == false)) {
      /* search in list of selected Pose-Channels for target */
      CTX_DATA_BEGIN (C, bPoseChannel *, pchan, selected_pose_bones_from_active_object) {
        /* just use the first one that we encounter, as long as it is not the active one */
        if (pchan != pchanact) {
          *tar_ob = obact;
          *tar_pchan = pchan;
          found = true;
  
          break;
        }
      }
      CTX_DATA_END;
    }
  
    /* if not yet found, try selected Objects... */
    if (found == false) {
      /* search in selected objects context */
      CTX_DATA_BEGIN (C, Object *, ob, selected_objects) {
        /* just use the first object we encounter (that isn't the active object)
         * and which fulfills the criteria for the object-target that we've got
         */
        if (ob != obact) {
          /* for armatures in pose mode, look inside the armature for the active bone
           * so that we set up cross-armature constraints with less effort
           */
          if ((ob->type == OB_ARMATURE) && (ob->mode & OB_MODE_POSE) &&
              (!only_curve && !only_mesh)) {
  
            /* Only use the object & bone if the bone is visible & selected
             * since we may have multiple objects in pose mode at once.  */
            bPoseChannel *pchan = BKE_pose_channel_active_or_first_selected(ob);
            if (pchan != NULL) {
              *tar_pchan = pchan;
              *tar_ob = ob;
              found = true;
            }
  
            break;
          }
          if (((!only_curve) || (ob->type == OB_CURVE)) && ((!only_mesh) || (ob->type == OB_MESH))) {
            /* set target */
            *tar_ob = ob;
            found = true;
  
            /* perform some special operations on the target */
            if (only_curve) {
              /* Curve-Path option must be enabled for follow-path constraints to be able to work
               */
              Curve *cu = (Curve *)ob->data;
              cu->flag |= CU_PATH;
            }
  
            break;
          }
        }
      }
      CTX_DATA_END;
    }
  
    /* if still not found, add a new empty to act as a target (if allowed) */
    if ((found == false) && (add)) {
      Main *bmain = CTX_data_main(C);
      ViewLayer *view_layer = CTX_data_view_layer(C);
      Base *base = BASACT(view_layer);
      Object *obt;
  
      /* add new target object */
      obt = BKE_object_add(bmain, view_layer, OB_EMPTY, NULL);
  
      /* transform cent to global coords for loc */
      if (pchanact) {
        /* Since by default, IK targets the tip of the last bone,
         * use the tip of the active PoseChannel if adding a target for an IK Constraint. */
        if (con_type == CONSTRAINT_TYPE_KINEMATIC) {
          mul_v3_m4v3(obt->loc, obact->obmat, pchanact->pose_tail);
        }
        else {
          mul_v3_m4v3(obt->loc, obact->obmat, pchanact->pose_head);
        }
      }
      else {
        copy_v3_v3(obt->loc, obact->obmat[3]);
      }
  
      /* restore, BKE_object_add sets active */
      BASACT(view_layer) = base;
      ED_object_base_select(base, BA_SELECT);
  
      /* make our new target the new object */
      *tar_ob = obt;
      found = true;
    }
  
    /* return whether there's any target */
    return found;
  }
  
  /* used by add constraint operators to add the constraint required */
  static int constraint_add_exec(
      bContext *C, wmOperator *op, Object *ob, ListBase *list, int type, const bool setTarget)
  {
    Main *bmain = CTX_data_main(C);
    bPoseChannel *pchan;
    bConstraint *con;
  
    if (list == &ob->constraints) {
      pchan = NULL;
    }
    else {
      pchan = BKE_pose_channel_active(ob);
  
      /* ensure not to confuse object/pose adding */
      if (pchan == NULL) {
        BKE_report(op->reports, RPT_ERROR, "No active pose bone to add a constraint to");
        return OPERATOR_CANCELLED;
      }
    }
    /* check if constraint to be added is valid for the given constraints stack */
    if (type == CONSTRAINT_TYPE_NULL) {
      return OPERATOR_CANCELLED;
    }
  
    /* Create a new constraint of the type required,
     * and add it to the active/given constraints list. */
    if (pchan) {
      con = BKE_constraint_add_for_pose(ob, pchan, NULL, type);
    }
    else {
      con = BKE_constraint_add_for_object(ob, NULL, type);
    }
  
    /* get the first selected object/bone, and make that the target
     * - apart from the buttons-window add buttons, we shouldn't add in this way
     */
    if (setTarget) {
      Object *tar_ob = NULL;
      bPoseChannel *tar_pchan = NULL;
  
      /* get the target objects, adding them as need be */
      if (get_new_constraint_target(C, type, &tar_ob, &tar_pchan, 1)) {
        /* Method of setting target depends on the type of target we've got - by default,
         * just set the first target (distinction here is only for multiple-targeted constraints).
         */
        if (tar_pchan) {
          set_constraint_nth_target(con, tar_ob, tar_pchan->name, 0);
        }
        else {
          set_constraint_nth_target(con, tar_ob, "", 0);
        }
      }
    }
  
    /* do type-specific tweaking to the constraint settings  */
    switch (type) {
      case CONSTRAINT_TYPE_PYTHON: /* FIXME: this code is not really valid anymore */
      {
  #ifdef WITH_PYTHON
        char *menustr;
        int scriptint = 0;
        /* popup a list of usable scripts */
        menustr = buildmenu_pyconstraints(bmain, NULL, &scriptint);
        /* XXX scriptint = pupmenu(menustr); */
        MEM_freeN(menustr);
  
        /* only add constraint if a script was chosen */
        if (scriptint) {
          /* add constraint */
          validate_pyconstraint_cb(bmain, con->data, &scriptint);
  
          /* make sure target allowance is set correctly */
          BPY_pyconstraint_update(ob, con);
        }
  #endif
        break;
      }
  
      default:
        break;
    }
  
    /* make sure all settings are valid - similar to above checks, but sometimes can be wrong */
    object_test_constraints(bmain, ob);
  
    if (pchan) {
      BKE_pose_update_constraint_flags(ob->pose);
    }
  
    /* force depsgraph to get recalculated since new relationships added */
    DEG_relations_tag_update(bmain);
  
    if ((ob->type == OB_ARMATURE) && (pchan)) {
      BKE_pose_tag_recalc(bmain, ob->pose); /* sort pose channels */
      if (BKE_constraints_proxylocked_owner(ob, pchan) && ob->adt) {
        /* We need to make use of ugly POSE_ANIMATION_WORKAROUND here too,
         * else anim data are not reloaded after calling `BKE_pose_rebuild()`, which causes T43872.
         * XXX Temp hack until new depsgraph hopefully solves this. */
        DEG_id_tag_update(&ob->id, ID_RECALC_ANIMATION);
      }
      DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY | ID_RECALC_TRANSFORM);
    }
    else {
      DEG_id_tag_update(&ob->id, ID_RECALC_TRANSFORM);
    }
  
    /* notifiers for updates */
    WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT | NA_ADDED, ob);
  
    return OPERATOR_FINISHED;
  }
  
  /* ------------------ */
  
  /* dummy operator callback */
  static int object_constraint_add_exec(bContext *C, wmOperator *op)
  {
    Object *ob = ED_object_active_context(C);
    int type = RNA_enum_get(op->ptr, "type");
    short with_targets = 0;
  
    if (!ob) {
      BKE_report(op->reports, RPT_ERROR, "No active object to add constraint to");
      return OPERATOR_CANCELLED;
    }
  
    /* hack: set constraint targets from selected objects in context is allowed when
     * operator name included 'with_targets', since the menu doesn't allow multiple properties
     */
    if (strstr(op->idname, "with_targets")) {
      with_targets = 1;
    }
  
    return constraint_add_exec(C, op, ob, &ob->constraints, type, with_targets);
  }
  
  /* dummy operator callback */
  static int pose_constraint_add_exec(bContext *C, wmOperator *op)
  {
    Object *ob = BKE_object_pose_armature_get(ED_object_active_context(C));
    int type = RNA_enum_get(op->ptr, "type");
    short with_targets = 0;
  
    if (!ob) {
      BKE_report(op->reports, RPT_ERROR, "No active object to add constraint to");
      return OPERATOR_CANCELLED;
    }
  
    /* hack: set constraint targets from selected objects in context is allowed when
     * operator name included 'with_targets', since the menu doesn't allow multiple properties
     */
    if (strstr(op->idname, "with_targets")) {
      with_targets = 1;
    }
  
    return constraint_add_exec(C, op, ob, ED_object_constraint_active_list(ob), type, with_targets);
  }
  
  /* ------------------ */
  
  /* Filters constraints that are only compatible with bones */
  static const EnumPropertyItem *object_constraint_add_itemf(bContext *UNUSED(C),
                                                             PointerRNA *UNUSED(ptr),
                                                             PropertyRNA *UNUSED(prop),
                                                             bool *r_free)
  {
    const EnumPropertyItem *item = rna_enum_constraint_type_items;
    EnumPropertyItem *object_constraint_items = NULL;
    int totitem = 0;
  
    while (item->identifier) {
      if ((item->value != CONSTRAINT_TYPE_KINEMATIC) && (item->value != CONSTRAINT_TYPE_SPLINEIK)) {
        RNA_enum_item_add(&object_constraint_items, &totitem, item);
      }
      item++;
    }
  
    RNA_enum_item_end(&object_constraint_items, &totitem);
    *r_free = true;
  
    return object_constraint_items;
  }
  
  void OBJECT_OT_constraint_add(wmOperatorType *ot)
  {
    PropertyRNA *prop;
  
    /* identifiers */
    ot->name = "Add Constraint";
    ot->description = "Add a constraint to the active object";
    ot->idname = "OBJECT_OT_constraint_add";
  
    /* api callbacks */
    ot->invoke = WM_menu_invoke;
    ot->exec = object_constraint_add_exec;
    ot->poll = ED_operator_object_active_editable;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    prop = RNA_def_enum(ot->srna, "type", DummyRNA_NULL_items, 0, "Type", "");
    RNA_def_enum_funcs(prop, object_constraint_add_itemf);
    ot->prop = prop;
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Add Constraints With Targets Operator
   * \{ */
  
  void OBJECT_OT_constraint_add_with_targets(wmOperatorType *ot)
  {
    PropertyRNA *prop;
  
    /* identifiers */
    ot->name = "Add Constraint (with Targets)";
    ot->description =
        "Add a constraint to the active object, with target (where applicable) set to the "
        "selected Objects/Bones";
    ot->idname = "OBJECT_OT_constraint_add_with_targets";
  
    /* api callbacks */
    ot->invoke = WM_menu_invoke;
    ot->exec = object_constraint_add_exec;
    ot->poll = ED_operator_object_active_editable;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    prop = RNA_def_enum(ot->srna, "type", DummyRNA_NULL_items, 0, "Type", "");
    RNA_def_enum_funcs(prop, object_constraint_add_itemf);
    ot->prop = prop;
  }
  
  void POSE_OT_constraint_add(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Add Constraint";
    ot->description = "Add a constraint to the active bone";
    ot->idname = "POSE_OT_constraint_add";
  
    /* api callbacks */
    ot->invoke = WM_menu_invoke;
    ot->exec = pose_constraint_add_exec;
    ot->poll = ED_operator_posemode_exclusive;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    ot->prop = RNA_def_enum(ot->srna, "type", rna_enum_constraint_type_items, 0, "Type", "");
  }
  
  void POSE_OT_constraint_add_with_targets(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Add Constraint (with Targets)";
    ot->description =
        "Add a constraint to the active bone, with target (where applicable) set to the selected "
        "Objects/Bones";
    ot->idname = "POSE_OT_constraint_add_with_targets";
  
    /* api callbacks */
    ot->invoke = WM_menu_invoke;
    ot->exec = pose_constraint_add_exec;
    ot->poll = ED_operator_posemode_exclusive;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    ot->prop = RNA_def_enum(ot->srna, "type", rna_enum_constraint_type_items, 0, "Type", "");
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Add IK to Bone Operator
   *
   * \note Only for pose-channels.
   * \{ */
  
  /* TODO: should these be here, or back in editors/armature/poseobject.c again? */
  
  /* present menu with options + validation for targets to use */
  static int pose_ik_add_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
  {
    Object *ob = BKE_object_pose_armature_get(CTX_data_active_object(C));
    bPoseChannel *pchan = BKE_pose_channel_active(ob);
    bConstraint *con = NULL;
  
    uiPopupMenu *pup;
    uiLayout *layout;
    Object *tar_ob = NULL;
    bPoseChannel *tar_pchan = NULL;
  
    /* must have active bone */
    if (ELEM(NULL, ob, pchan)) {
      BKE_report(op->reports, RPT_ERROR, "Must have an active bone to add IK constraint to");
      return OPERATOR_CANCELLED;
    }
  
    /* bone must not have any constraints already */
    for (con = pchan->constraints.first; con; con = con->next) {
      if (con->type == CONSTRAINT_TYPE_KINEMATIC) {
        break;
      }
    }
    if (con) {
      BKE_report(op->reports, RPT_ERROR, "Bone already has an IK constraint");
      return OPERATOR_CANCELLED;
    }
  
    /* prepare popup menu to choose targeting options */
    pup = UI_popup_menu_begin(C, IFACE_("Add IK"), ICON_NONE);
    layout = UI_popup_menu_layout(pup);
  
    /* the type of targets we'll set determines the menu entries to show... */
    if (get_new_constraint_target(C, CONSTRAINT_TYPE_KINEMATIC, &tar_ob, &tar_pchan, 0)) {
      /* bone target, or object target?
       * - the only thing that matters is that we want a target...
       */
      if (tar_pchan) {
        uiItemBooleanO(
            layout, IFACE_("To Active Bone"), ICON_NONE, "POSE_OT_ik_add", "with_targets", 1);
      }
      else {
        uiItemBooleanO(
            layout, IFACE_("To Active Object"), ICON_NONE, "POSE_OT_ik_add", "with_targets", 1);
      }
    }
    else {
      /* we have a choice of adding to a new empty, or not setting any target (targetless IK) */
      uiItemBooleanO(
          layout, IFACE_("To New Empty Object"), ICON_NONE, "POSE_OT_ik_add", "with_targets", 1);
      uiItemBooleanO(
          layout, IFACE_("Without Targets"), ICON_NONE, "POSE_OT_ik_add", "with_targets", 0);
    }
  
    /* finish building the menu, and process it (should result in calling self again) */
    UI_popup_menu_end(C, pup);
  
    return OPERATOR_INTERFACE;
  }
  
  /* call constraint_add_exec() to add the IK constraint */
  static int pose_ik_add_exec(bContext *C, wmOperator *op)
  {
    Object *ob = CTX_data_active_object(C);
    const bool with_targets = RNA_boolean_get(op->ptr, "with_targets");
  
    /* add the constraint - all necessary checks should have
     * been done by the invoke() callback already... */
    return constraint_add_exec(
        C, op, ob, ED_object_constraint_active_list(ob), CONSTRAINT_TYPE_KINEMATIC, with_targets);
  }
  
  void POSE_OT_ik_add(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Add IK to Bone";
    ot->description = "Add IK Constraint to the active Bone";
    ot->idname = "POSE_OT_ik_add";
  
    /* api callbacks */
    ot->invoke = pose_ik_add_invoke;
    ot->exec = pose_ik_add_exec;
    ot->poll = ED_operator_posemode_exclusive;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  
    /* properties */
    RNA_def_boolean(ot->srna,
                    "with_targets",
                    1,
                    "With Targets",
                    "Assign IK Constraint with targets derived from the select bones/objects");
  }
  
  /** \} */
  
  /* ------------------------------------------------------------------- */
  /** \name Clear IK from Bone Operator
   *
   * Remove IK constraints from selected bones.
   * \{ */
  
  static int pose_ik_clear_exec(bContext *C, wmOperator *UNUSED(op))
  {
    Object *prev_ob = NULL;
  
    /* only remove IK Constraints */
    CTX_DATA_BEGIN_WITH_ID (C, bPoseChannel *, pchan, selected_pose_bones, Object *, ob) {
      bConstraint *con, *next;
  
      /* TODO: should we be checking if these constraints were local
       * before we try and remove them? */
      for (con = pchan->constraints.first; con; con = next) {
        next = con->next;
        if (con->type == CONSTRAINT_TYPE_KINEMATIC) {
          BKE_constraint_remove(&pchan->constraints, con);
        }
      }
      pchan->constflag &= ~(PCHAN_HAS_IK | PCHAN_HAS_TARGET);
  
      if (prev_ob != ob) {
        prev_ob = ob;
  
        /* Refresh depsgraph. */
        DEG_id_tag_update(&ob->id, ID_RECALC_GEOMETRY);
  
        /* Note, notifier might evolve. */
        WM_event_add_notifier(C, NC_OBJECT | ND_CONSTRAINT | NA_REMOVED, ob);
      }
    }
    CTX_DATA_END;
  
    return OPERATOR_FINISHED;
  }
  
  void POSE_OT_ik_clear(wmOperatorType *ot)
  {
    /* identifiers */
    ot->name = "Remove IK";
    ot->description = "Remove all IK Constraints from selected bones";
    ot->idname = "POSE_OT_ik_clear";
  
    /* api callbacks */
    ot->exec = pose_ik_clear_exec;
    ot->poll = ED_operator_posemode_exclusive;
  
    /* flags */
    ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
  }
  
  /** \} */
  