/* global CodeMirror, mw, $ */

var initExtCodeMirror = function() {
	var origTextSelection = $.fn.textSelection, codeMirror = false;

	// Replace jquery.textSelection.js
	var cmTextSelection = function ( command, options ) {
		if ( ! codeMirror ) {
			return origTextSelection( command, options );
		}
		var fn, retval;

		fn = {
			/**
			 * Get the contents of the textarea
			 */
			getContents: function () {
				return codeMirror.doc.getValue();
			},

			/**
			 * Get the currently selected text in this textarea. Will focus the textarea
			 * in some browsers (IE/Opera)
			 */
			getSelection: function () {
				return codeMirror.doc.getSelection();
			},

			/**
			 * Inserts text at the beginning and end of a text selection, optionally
			 * inserting text at the caret when selection is empty.
			 */
			encapsulateSelection: function ( options ) {
				return this.each( function () {
					var insertText, selText,
							selectPeri = options.selectPeri,
							pre = options.pre, post = options.post;

					if ( options.selectionStart !== undefined ) {
						//fn[command].call( this, options );
						fn.setSelection( { 'start': options.selectionStart, 'end': options.selectionEnd } ); // not tested
					}

					selText = codeMirror.doc.getSelection();
					if ( !selText ) {
						selText = options.peri;
					} else if ( options.replace ) {
						selectPeri = false;
						selText = options.peri;
					} else {
						selectPeri = false;
						while ( selText.charAt( selText.length - 1 ) === ' ' ) {
							// Exclude ending space char
							selText = selText.substring( 0, selText.length - 1 );
							post += ' ';
						}
						while ( selText.charAt( 0 ) === ' ' ) {
							// Exclude prepending space char
							selText = selText.substring( 1, selText.length );
							pre = ' ' + pre;
						}
					}

					/**
					* Do the splitlines stuff.
					*
					* Wrap each line of the selected text with pre and post
					*/
					function doSplitLines( selText, pre, post ) {
						var i,
							insertText = '',
							selTextArr = selText.split( '\n' );
						for ( i = 0; i < selTextArr.length; i++ ) {
							insertText += pre + selTextArr[i] + post;
							if ( i !== selTextArr.length - 1 ) {
								insertText += '\n';
							}
						}
						return insertText;
					}

					if ( options.splitlines ) {
						selectPeri = false;
						insertText = doSplitLines( selText, pre, post );
					} else {
						insertText = pre + selText + post;
					}

					var startCursor = codeMirror.doc.getCursor( true );
					if ( options.ownline ) {
						if ( startCursor.ch !== 0 ) {
							insertText = '\n' + insertText;
							pre += '\n';
						}
						var endCursor = codeMirror.doc.getCursor( false );
						if ( codeMirror.doc.getLine( endCursor.line ).length !== endCursor.ch ) {
							insertText += '\n';
							post += '\n';
						}
					}

					codeMirror.doc.replaceSelection( insertText );

					if ( selectPeri ) {
						codeMirror.doc.setSelection(
								codeMirror.doc.posFromIndex( codeMirror.doc.indexFromPos( startCursor ) + pre.length ),
								codeMirror.doc.posFromIndex( codeMirror.doc.indexFromPos( startCursor ) + pre.length + selText.length )
							);
					}
				});
			},

			/**
			 * Get the position (in resolution of bytes not necessarily characters)
			 * in a textarea
			 */
			getCaretPosition: function ( options ) {
				var caretPos = codeMirror.doc.indexFromPos( codeMirror.doc.getCursor( true ) );
				if ( options.startAndEnd ) {
					var endPos = codeMirror.doc.indexFromPos( codeMirror.doc.getCursor( false ) );
					return [ caretPos, endPos ];
				}
				return caretPos;
			},

			 setSelection: function ( options ) {
				return this.each( function () {
					codeMirror.doc.setSelection( codeMirror.doc.posFromIndex( options.start ), codeMirror.doc.posFromIndex( options.end ) );
				});
			 },

			/**
			* Scroll a textarea to the current cursor position. You can set the cursor
			* position with setSelection()
			* @param options boolean Whether to force a scroll even if the caret position
			*  is already visible. Defaults to false
			*/
			scrollToCaretPosition: function ( /* options */ ) {
				return this.each(function () {
					codeMirror.scrollIntoView( null );
				});
			}
		};

		switch ( command ) {
			//case 'getContents': // no params
			//case 'setContents': // no params with defaults
			//case 'getSelection': // no params
			case 'encapsulateSelection':
				options = $.extend( {
					pre: '', // Text to insert before the cursor/selection
					peri: '', // Text to insert between pre and post and select afterwards
					post: '', // Text to insert after the cursor/selection
					ownline: false, // Put the inserted text on a line of its own
					replace: false, // If there is a selection, replace it with peri instead of leaving it alone
					selectPeri: true, // Select the peri text if it was inserted (but not if there was a selection and replace==false, or if splitlines==true)
					splitlines: false, // If multiple lines are selected, encapsulate each line individually
					selectionStart: undefined, // Position to start selection at
					selectionEnd: undefined // Position to end selection at. Defaults to start
				}, options );
				break;
			case 'getCaretPosition':
				options = $.extend( {
					// Return [start, end] instead of just start
					startAndEnd: false
				}, options );
				// FIXME: We may not need character position-based functions if we insert markers in the right places
				break;
			case 'setSelection':
				options = $.extend( {
					// Position to start selection at
					start: undefined,
					// Position to end selection at. Defaults to start
					end: undefined,
					// Element to start selection in (iframe only)
					startContainer: undefined,
					// Element to end selection in (iframe only). Defaults to startContainer
					endContainer: undefined
				}, options );

				if ( options.end === undefined ) {
					options.end = options.start;
				}
				if ( options.endContainer === undefined ) {
					options.endContainer = options.startContainer;
				}
				// FIXME: We may not need character position-based functions if we insert markers in the right places
				break;
			case 'scrollToCaretPosition':
				options = $.extend( {
					force: false // Force a scroll even if the caret position is already visible
				}, options );
				break;
		}

		retval = fn[command].call( this, options );
		codeMirror.focus();

		return retval;
	};

	function setCodeEditorPreference( prefValue ) {
		var api = new mw.Api();
		api.postWithToken( 'options', {
			action: 'options',
			optionname: 'usecodemirror',
			optionvalue: prefValue ? 1 : 0
		} ).fail( function ( code, result ) {
			mw.log.error( 'Failed to set code editor preference: ' + code + '\n' + result.error );
		} );
	}

	if ( mw.user.options.get( 'usecodemirror' ) === '1' || mw.user.options.get( 'usecodemirror' ) === 1 ) {
		codeMirror = true;
	}

	function addCodeMirrorToWikiEditor() {
		(function waitWikiEditor() {
			if ( $( '#wikiEditor-section-main' ).length > 0 ) {
				$( '#wpTextbox1' ).wikiEditor(
						'addToToolbar',
						{
							'section': 'main',
							'groups': {
								'codemirror':{
		//							'label': 'CodeMirror',
									'tools': {
										'CodeMirror': {
											label: 'CodeMirror',
											type: 'button',
											icon: mw.config.get( 'wgExtensionAssetsPath' ) + '/CodeMirror/resources/images/cm-' + (codeMirror ? 'on.png' : 'off.png'),
											action: {type: 'callback', execute: function( context ){ switchCodeMirror( context ); } }
		//								},
		//								'Undo':{
		//									label: 'Undo',
		//									type: 'button',
		//									icon: mw.config.get( 'wgExtensionAssetsPath' ) + '/CodeMirror/resources/images/undo.png',
		//									action: {type: 'callback', execute: function(context){alert(context);} }
		//								},
		//								'Redo':{
		//									label: 'Redo',
		//									type: 'button',
		//									icon: mw.config.get( 'wgExtensionAssetsPath' ) + '/CodeMirror/resources/images/redo.png',
		//									action: {type: 'callback', execute: function(context){alert(context);} }
										}
									}
								}
							}
						}
					);
			} else {
				setTimeout( waitWikiEditor, 500 );
			}
		})();
	}

	if ( $( '#wpTextbox1' ).wikiEditor && mw.user.options.get( 'usebetatoolbar' ) === 1 && mw.user.options.get( 'showtoolbar' ) === 1 ) {
		addCodeMirrorToWikiEditor();
	} else {
		var $image = $( '<img>' ).attr( {
			width: 23,
			height: 22,
			src: mw.config.get( 'wgExtensionAssetsPath' ) + '/CodeMirror/resources/images/old-cm-' + (codeMirror ? 'on.png' : 'off.png'),
			alt: 'CodeMirror',
			title: 'CodeMirror',
			id: 'CodeMirrorButton',
			'class': 'mw-toolbar-editbutton'
		} ).click( function () {
			switchCodeMirror( false );
			return false;
		} );

		$( '#toolbar' ).append( $image );
	}

	function switchCodeMirror( context ) {
		//alert( 'switchCodeMirror: ' + codeMirror );
		var $img, $src;
		if ( context !== false ) {
			$img = context.modules.toolbar.$toolbar.find( 'img.tool[rel=CodeMirror]' );
		} else {
			$img = $( '#CodeMirrorButton' );
		}

		if ( codeMirror ) {
			setCodeEditorPreference( false );
			codeMirror.save();
			codeMirror.toTextArea();
			codeMirror = false;
			$.fn.textSelection = origTextSelection;
			$src = mw.config.get( 'wgExtensionAssetsPath' ) + '/CodeMirror/resources/images/' + (context ? 'cm-off.png' : 'old-cm-off.png' );
			$img.attr( 'src', $src );
		} else {
			enableCodeMirror();
			$src = mw.config.get( 'wgExtensionAssetsPath' ) + '/CodeMirror/resources/images/' + (context ? 'cm-on.png' : 'old-cm-on.png' );
			$img.attr( 'src', $src );
			setCodeEditorPreference( true );
		}
	}

	function enableCodeMirror() {
		var textbox1 = $( '#wpTextbox1' );
		if ( textbox1[0].style.display === 'none' ) {
			return;
		}
		codeMirror = CodeMirror.fromTextArea( textbox1[0], {
				mwextFunctionSynonyms: mw.config.get( 'extCodeMirrorFunctionSynonyms' ),
				mwextTags: mw.config.get( 'extCodeMirrorTags' ),
				mwextDoubleUnderscore: mw.config.get( 'extCodeMirrorDoubleUnderscore' ),
				mwextUrlProtocols: mw.config.get( 'extCodeMirrorUrlProtocols' ),
				mwextMode: mw.config.get( 'extCodeMirrorExtMode' ),
				//matchMW: true,
				styleActiveLine: true,
				//gutters: ['CodeMirror-mediawiki-gutter'],
				//lint: true,
				lineWrapping: true,
				//indentUnit: 4,
				//indentWithTabs: true,
				//matchBrackets: true,
				//autoCloseBrackets: true,
				mode: 'text/mediawiki'
			} );

		if ( window.navigator.userAgent.indexOf('Trident/') > -1 ) { //IE specific code goes here
			$( '.CodeMirror' ).addClass( 'CodeMirrorIE' );
		}

		codeMirror.setSize( null, textbox1.height() );
		$.fn.textSelection = cmTextSelection;
	}

	if ( codeMirror ) {
		enableCodeMirror();
	}
};

$.when(
	$.ready,
	mw.loader.using( ['user.options', 'jquery.textSelection', 'mediawiki.api'] )
).done( initExtCodeMirror() );