/**
 * @file lv_group.h
 *
 */

#ifndef LV_GROUP_H
#define LV_GROUP_H

#ifdef __cplusplus
extern "C" {
#endif

/*********************
 *      INCLUDES
 *********************/

#include "../lv_conf_internal.h"

#include <stdint.h>
#include <stdbool.h>
#include "../misc/lv_ll.h"
#include "../misc/lv_types.h"

/*********************
 *      DEFINES
 *********************/
/*Predefined keys to control the focused object via lv_group_send(group, c)*/
enum _lv_key_t {
    LV_KEY_UP        = 17,  /*0x11*/
    LV_KEY_DOWN      = 18,  /*0x12*/
    LV_KEY_RIGHT     = 19,  /*0x13*/
    LV_KEY_LEFT      = 20,  /*0x14*/
    LV_KEY_ESC       = 27,  /*0x1B*/
    LV_KEY_DEL       = 127, /*0x7F*/
    LV_KEY_BACKSPACE = 8,   /*0x08*/
    LV_KEY_ENTER     = 10,  /*0x0A, '\n'*/
    LV_KEY_NEXT      = 9,   /*0x09, '\t'*/
    LV_KEY_PREV      = 11,  /*0x0B, '*/
    LV_KEY_HOME      = 2,   /*0x02, STX*/
    LV_KEY_END       = 3,   /*0x03, ETX*/
};

#ifdef DOXYGEN
typedef _lv_key_t lv_key_t;
#else
typedef uint8_t lv_key_t;
#endif /*DOXYGEN*/



/**********************
 *      TYPEDEFS
 **********************/

struct _lv_obj_t;
struct _lv_group_t;

typedef void (*lv_group_focus_cb_t)(struct _lv_group_t *);
typedef void (*lv_group_edge_cb_t)(struct _lv_group_t *, bool);

/**
 * Groups can be used to logically hold objects so that they can be individually focused.
 * They are NOT for laying out objects on a screen (try layouts for that).
 */
typedef struct _lv_group_t {
    lv_ll_t obj_ll;        /**< Linked list to store the objects in the group*/
    struct _lv_obj_t ** obj_focus; /**< The object in focus*/

    lv_group_focus_cb_t focus_cb;              /**< A function to call when a new object is focused (optional)*/
    lv_group_edge_cb_t  edge_cb;               /**< A function to call when an edge is reached, no more focus
                                                    targets are available in this direction (to allow edge feedback
                                                    like a sound or a scroll bounce) */

    void * user_data;

    uint8_t frozen : 1;         /**< 1: can't focus to new object*/
    uint8_t editing : 1;        /**< 1: Edit mode, 0: Navigate mode*/
    uint8_t refocus_policy : 1; /**< 1: Focus prev if focused on deletion. 0: Focus next if focused on
                                   deletion.*/
    uint8_t wrap : 1;           /**< 1: Focus next/prev can wrap at end of list. 0: Focus next/prev stops at end
                                   of list.*/
} lv_group_t;


typedef enum {
    LV_GROUP_REFOCUS_POLICY_NEXT = 0,
    LV_GROUP_REFOCUS_POLICY_PREV = 1
} lv_group_refocus_policy_t;

/**********************
 * GLOBAL PROTOTYPES
 **********************/

/**
 * Init. the group module
 * @remarks Internal function, do not call directly.
 */
void _lv_group_init(void);

/**
 * Create a new object group
 * @return          pointer to the new object group
 */
lv_group_t * lv_group_create(void);

/**
 * Delete a group object
 * @param group     pointer to a group
 */
void lv_group_delete(lv_group_t * group);

/**
 * Set a default group. New object are added to this group if it's enabled in their class with `add_to_def_group = true`
 * @param group     pointer to a group (can be `NULL`)
 */
void lv_group_set_default(lv_group_t * group);

/**
 * Get the default group
 * @return          pointer to the default group
 */
lv_group_t * lv_group_get_default(void);

/**
 * Add an object to a group
 * @param group     pointer to a group
 * @param obj       pointer to an object to add
 */
void lv_group_add_obj(lv_group_t * group, struct _lv_obj_t * obj);

/**
 * Swap 2 object in a group. The object must be in the same group
 * @param obj1  pointer to an object
 * @param obj2  pointer to an other object
 */
void lv_group_swap_obj(struct _lv_obj_t * obj1, struct _lv_obj_t * obj2);

/**
 * Remove an object from its group
 * @param obj       pointer to an object to remove
 */
void lv_group_remove_obj(struct _lv_obj_t * obj);

/**
 * Remove all objects from a group
 * @param group     pointer to a group
 */
void lv_group_remove_all_objs(lv_group_t * group);

/**
 * Focus on an object (defocus the current)
 * @param obj       pointer to an object to focus on
 */
void lv_group_focus_obj(struct _lv_obj_t * obj);

/**
 * Focus the next object in a group (defocus the current)
 * @param group     pointer to a group
 */
void lv_group_focus_next(lv_group_t * group);

/**
 * Focus the previous object in a group (defocus the current)
 * @param group     pointer to a group
 */
void lv_group_focus_prev(lv_group_t * group);

/**
 * Do not let to change the focus from the current object
 * @param group     pointer to a group
 * @param en        true: freeze, false: release freezing (normal mode)
 */
void lv_group_focus_freeze(lv_group_t * group, bool en);

/**
 * Send a control character to the focuses object of a group
 * @param group     pointer to a group
 * @param c         a character (use LV_KEY_.. to navigate)
 * @return          result of focused object in group.
 */
lv_result_t lv_group_send_data(lv_group_t * group, uint32_t c);

/**
 * Set a function for a group which will be called when a new object is focused
 * @param group         pointer to a group
 * @param focus_cb      the call back function or NULL if unused
 */
void lv_group_set_focus_cb(lv_group_t * group, lv_group_focus_cb_t focus_cb);

/**
 * Set a function for a group which will be called when a focus edge is reached
 * @param group         pointer to a group
 * @param edge_cb      the call back function or NULL if unused
 */
void lv_group_set_edge_cb(lv_group_t * group, lv_group_edge_cb_t edge_cb);


/**
 * Set whether the next or previous item in a group is focused if the currently focused obj is
 * deleted.
 * @param group         pointer to a group
 * @param policy        new refocus policy enum
 */
void lv_group_set_refocus_policy(lv_group_t * group, lv_group_refocus_policy_t policy);

/**
 * Manually set the current mode (edit or navigate).
 * @param group         pointer to group
 * @param edit          true: edit mode; false: navigate mode
 */
void lv_group_set_editing(lv_group_t * group, bool edit);

/**
 * Set whether focus next/prev will allow wrapping from first->last or last->first object.
 * @param group         pointer to group
 * @param               en true: wrapping enabled; false: wrapping disabled
 */
void lv_group_set_wrap(lv_group_t * group, bool en);

/**
 * Get the focused object or NULL if there isn't one
 * @param group         pointer to a group
 * @return              pointer to the focused object
 */
struct _lv_obj_t * lv_group_get_focused(const lv_group_t * group);

/**
 * Get the focus callback function of a group
 * @param group pointer to a group
 * @return the call back function or NULL if not set
 */
lv_group_focus_cb_t lv_group_get_focus_cb(const lv_group_t * group);

/**
 * Get the edge callback function of a group
 * @param group pointer to a group
 * @return the call back function or NULL if not set
 */
lv_group_edge_cb_t lv_group_get_edge_cb(const lv_group_t * group);

/**
 * Get the current mode (edit or navigate).
 * @param group         pointer to group
 * @return              true: edit mode; false: navigate mode
 */
bool lv_group_get_editing(const lv_group_t * group);

/**
 * Get whether focus next/prev will allow wrapping from first->last or last->first object.
 * @param group         pointer to group
 * @param               en true: wrapping enabled; false: wrapping disabled
 */
bool lv_group_get_wrap(lv_group_t * group);

/**
 * Get the number of object in the group
 * @param group         pointer to a group
 * @return              number of objects in the group
 */
uint32_t lv_group_get_obj_count(lv_group_t * group);

/**
 * Get the number of groups
 * @return              number of groups
 */
uint32_t lv_group_get_count(void);

/**
 * Get a group by its index
 * @return              pointer to the group
 */
lv_group_t  * lv_group_by_index(uint32_t index);

/**********************
 *      MACROS
 **********************/

#ifdef __cplusplus
} /*extern "C"*/
#endif

#endif /*LV_GROUP_H*/
