text: //
  //   Copyright 2014 Slack Technologies, Inc.
  //
  //   Licensed under the Apache License, Version 2.0 (the "License");
  //   you may not use this file except in compliance with the License.
  //   You may obtain a copy of the License at
  //
  //       http://www.apache.org/licenses/LICENSE-2.0
  //
  //   Unless required by applicable law or agreed to in writing, software
  //   distributed under the License is distributed on an "AS IS" BASIS,
  //   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  //   See the License for the specific language governing permissions and
  //   limitations under the License.
  //
  
  // 版权属于原作者
  // http://code4app.com (cn) http://code4app.net (en)
  // 发布代码于最专业的源码分享网站: Code4App.com
  
  #import <UIKit/UIKit.h>
  #import "SLKTextInputbar.h"
  #import "SLKTypingIndicatorView.h"
  #import "SLKTextView.h"
  
  #import "UIScrollView+SLKAdditions.h"
  #import "UITextView+SLKAdditions.h"
  #import "UIView+SLKAdditions.h"
  
  /** @name A drop-in UIViewController subclass with a growing text input view and other useful messaging features. */
  @interface SLKTextViewController : UIViewController <UITableViewDelegate, UITableViewDataSource, UICollectionViewDelegate, UICollectionViewDataSource>
  
  /** The main table view managed by the controller object. Default view if initialized with -init */
  @property (nonatomic, readonly) UITableView *tableView;
  
  /** The main collection view managed by the controller object. Not nil if the controller is initialised with -initWithCollectionViewLayout: */
  @property (nonatomic, readonly) UICollectionView *collectionView;
  
  /** The bottom toolbar containing a text view and buttons. */
  @property (nonatomic, readonly) SLKTextInputbar *textInputbar;
  
  /** The typing indicator used to display user names horizontally. */
  @property (nonatomic, readonly) SLKTypingIndicatorView *typingIndicatorView;
  
  /** YES if control's animation should have bouncy effects. Default is YES. */
  @property (nonatomic, assign) BOOL bounces;
  
  /** YES if text view's content can be cleaned with a shake gesture. Default is NO. */
  @property (nonatomic, assign) BOOL undoShakingEnabled;
  
  /** YES if keyboard can be dismissed gradually with a vertical panning gesture. Default is YES. */
  @property (nonatomic, assign) BOOL keyboardPanningEnabled;
  
  /** YES if the main table view is inverted. Default is YES.
   @discussion This allows the table view to start from the bottom like any typical messaging interface.
   If inverted, you must assign the same transform property to your cells to match the orientation (ie: cell.transform = tableView.transform;)
   Inverting the table view will enable some great features such as content offset corrections automatically when resizing the text input and/or showing autocompletion.
   
   Updating this value also changes 'edgesForExtendedLayout' value. When inverted, it must be UIRectEdgeNone, to display correctly all the elements. Otherwise, UIRectEdgeAll is set.
   */
  @property (nonatomic, assign, getter = isInverted) BOOL inverted;
  
  /** Convenience accessors (accessed through the text input bar) */
  @property (nonatomic, readonly) SLKTextView *textView;
  @property (nonatomic, readonly) UIButton *leftButton;
  @property (nonatomic, readonly) UIButton *rightButton;
  
  /**
   Initializes a text view controller to manage a table view of a given style.
   @discussion If you use the standard -init method, a table view with plain style will be created.
   
   @param style A constant that specifies the style of main table view that the controller object is to manage (UITableViewStylePlain or UITableViewStyleGrouped).
   @return An initialized SLKTextViewController object or nil if the object could not be created.
   */
  - (instancetype)initWithTableViewStyle:(UITableViewStyle)style;
  
  /**
   Initializes a text view controller controller and configures the collection view with the provided layout.
   @discussion If you use the standard -init method, a table view with plain style will be created.
  
   @param layout The layout object to associate with the collection view. The layout controls how the collection view presents its cells and supplementary views.
   @return An initialized SLKTextViewController object or nil if the object could not be created.
   */
  - (instancetype)initWithCollectionViewLayout:(UICollectionViewLayout *)layout;
  
  /**
   Verifies if the right button can be pressed. If NO, the button is disabled.
   @discussion You can override this method to perform additional tasks.
   
   @return YES if the right button can be pressed.
   */
  - (BOOL)canPressRightButton;
  
  /**
   Presents the keyboard, if not already, animated.
   
   @param animated YES if the keyboard should show using an animation.
   */
  - (void)presentKeyboard:(BOOL)animated;
  
  /**
   Dimisses the keyboard, if not already, animated.
   
   @param animated YES if the keyboard should be dismissed using an animation.
   */
  - (void)dismissKeyboard:(BOOL)animated;
  
  
  ///------------------------------------------------
  /// @name Text Typing Notifications
  ///------------------------------------------------
  
  /**
   Notifies the view controller that the text will update.
   @discussion You can override this method to perform additional tasks associated with presenting the view. You MUST call super at some point in your implementation.
   */
  - (void)textWillUpdate;
  
  /**
   Notifies the view controller that the text did update.
   @discussion You can override this method to perform additional tasks associated with presenting the view. You MUST call super at some point in your implementation.
   
   @param If YES, the text input bar was resized using an animation.
   */
  - (void)textDidUpdate:(BOOL)animated;
  
  /**
   Notifies the view controller when the left button's action has been triggered, manually.
   @discussion You can override this method to perform additional tasks associated with the left button. You MUST call super at some point in your implementation.
   
   @param sender The object calling this method.
   */
  - (void)didPressLeftButton:(id)sender;
  
  /**
   Notifies the view controller when the right button's action has been triggered, manually or by using the keyboard return key.
   @discussion You can override this method to perform additional tasks associated with the right button. You MUST call super at some point in your implementation.
   
   @param sender The object calling this method.
   */
  - (void)didPressRightButton:(id)sender;
  
  /**
   Notifies the view controller when the user has pasted an image inside of the text view.
   @discussion You can override this method to perform additional tasks associated with image pasting.
   
   @param image The image that has been pasted. Only JPG or PNG are supported.
   */
  - (void)didPasteImage:(UIImage *)image;
  
  /**
   Verifies that the typing indicator view should be shown. Default is YES, if meeting some requierements.
   @discussion You must override this method to perform perform additional verifications before displaying the typing indicator.
   
   @return YES if the typing indicator view should be shown.
   */
  - (BOOL)canShowTypeIndicator;
  
  /**
   Notifies the view controller when the user has shaked the device for undoing text typing.
   @discussion You can override this method to perform additional tasks associated with the shake gesture. Calling super will prompt a system alert view with undo option. This will not be called if 'undoShakingEnabled' is set to NO and/or if the text view's content is empty.
   */
  - (void)willRequestUndo;
  
  /**
   Notifies the view controller when the user has pressed the Return key (↵) with an external keyboard.
   @discussion You can override this method to perform additional tasks.
   */
  - (void)didPressReturnKey:(id)sender;
  
  /**
   Notifies the view controller when the user has pressed the Escape key (Esc) with an external keyboard.
   @discussion You can override this method to perform additional tasks.
   */
  - (void)didPressEscapeKey:(id)sender;
  
  ///------------------------------------------------
  /// @name Text Edition
  ///------------------------------------------------
  
  /** YES if the text editing mode is active. */
  @property (nonatomic, readonly, getter = isEditing) BOOL editing;
  
  /**
   Re-uses the text layout for edition, displaying an accessory view on top of the text input bar with options (cancel & save).
   @discussion You can override this method to perform additional tasks. You MUST call super at some point in your implementation.
  
   @param text The string text to edit.
   */
  - (void)editText:(NSString *)text;
  
  /**
   Notifies the view controller when the editing bar's right button's action has been triggered, manually or by using the external keyboard's Return key.
   @discussion You can override this method to perform additional tasks associated with accepting changes. You MUST call super at some point in your implementation.
   
   @param sender The object calling this method.
   */
  - (void)didCommitTextEditing:(id)sender;
  
  /**
   Notifies the view controller when the editing bar's right button's action has been triggered, manually or by using the external keyboard's Esc key.
   @discussion You can override this method to perform additional tasks associated with accepting changes. You MUST call super at some point in your implementation.
   
   @param sender The object calling this method.
   */
  - (void)didCancelTextEditing:(id)sender;
  
  
  ///------------------------------------------------
  /// @name Text Typing Auto-Completion
  ///------------------------------------------------
  
  /** The table view used to display autocompletion results. */
  @property (nonatomic, readonly) UITableView *autoCompletionView;
  
  /** The recently found prefix symbol used as prefix for autocompletion mode. */
  @property (nonatomic, readonly) NSString *foundPrefix;
  
  /** The recently found word at the textView caret position. */
  @property (nonatomic, readonly) NSString *foundWord;
  
  /** YES if the autocompletion mode is active. */
  @property (nonatomic, readonly, getter = isAutoCompleting) BOOL autoCompleting;
  
  /** An array containing all the registered prefix strings for autocompletion. */
  @property (nonatomic, readonly) NSArray *registeredPrefixes;
  
  /**
   Registers any string prefix for autocompletion detection, useful for user mentions and/or hashtags autocompletion.
   @discussion The prefix must be valid NSString (i.e: '@', '#', '\', and so on)
   This also checks if no repeated prefix is inserted.
   
   @param prefixes An array of prefix strings.
   */
  - (void)registerPrefixesForAutoCompletion:(NSArray *)prefixes;
  
  /**
   Verifies that the autocompletion view should be shown. Default is NO.
   @discussion You must override this method to perform additional tasks, before autocompletion is shown, like populating the data source.
   
   @return YES if the autocompletion view should be shown.
   */
  - (BOOL)canShowAutoCompletion;
  
  /**
   Returns a custom height for the autocompletion view. Default is 0.0.
   @discussion You can override this method to return a custom height.
  
   @return The autocompletion view's height.
   */
  - (CGFloat)heightForAutoCompletionView;
  
  /**
   Returns the maximum height for the autocompletion view. Default is 140.0.
   @discussion You can override this method to return a custom max height.
  
   @return The autocompletion view's max height.
   */
  - (CGFloat)maximumHeightForAutoCompletionView;
  
  /**
   Cancels and hides the autocompletion view, animated
   */
  - (void)cancelAutoCompletion;
  
  /** 
   Accepts the autocompletion, replacing the detected key and word with a new string.
   
   @param string The string to be used for replacing autocompletion placeholders.
   */
  - (void)acceptAutoCompletionWithString:(NSString *)string;
  
  
  ///------------------------------------------------
  /// @name Miscellaneous
  ///------------------------------------------------
  
  /**
   Allows subclasses to use the super implementation of this method.
   */
  - (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer;
  
  @end
  