/**
 * VisualEditor user interface IndentationButtonTool class.
 *
 * @copyright 2011-2012 VisualEditor Team and others; see AUTHORS.txt
 * @license The MIT License (MIT); see LICENSE.txt
 */

/**
 * Creates an ve.ui.IndentationButtonTool object.
 *
 * @class
 * @constructor
 * @extends {ve.ui.ButtonTool}
 * @param {ve.ui.Toolbar} toolbar
 * @param {String} name
 * @param title
 * @param data
 */
ve.ui.IndentationButtonTool = function VeUiIndentationButtonTool( toolbar, name, title, data ) {
	// Parent constructor
	ve.ui.ButtonTool.call( this, toolbar, name, title );

	this.data = data;
};

/* Inheritance */

ve.inheritClass( ve.ui.IndentationButtonTool, ve.ui.ButtonTool );

/* Methods */

ve.ui.IndentationButtonTool.prototype.onClick = function () {
	if ( !this.$.hasClass( 've-ui-toolbarButtonTool-disabled' ) ) {
		var listItems = [],
			listItem,
			i;
		// FIXME old code, doesn't work
		for ( i = 0; i < this.nodes.length; i++ ) {
			listItem = this.nodes[i].getParent();
			if ( listItems.length > 0 ) {
				if (listItem !== listItems[listItems.length - 1]) {
					listItems.push( listItem );
				}
			} else {
				listItems.push( listItem );
			}
		}
		if ( this.name === 'indent' ) {
			this.indent( listItems );
		} else if ( this.name === 'outdent' ) {
			this.outdent( listItems );
		}
	}
};

ve.ui.IndentationButtonTool.prototype.indent = function ( listItems ) {
	ve.ui.IndentationButtonTool.indentListItem( this.toolbar.getSurfaceView().getModel() );
};

ve.ui.IndentationButtonTool.prototype.outdent = function ( listItems ) {
	ve.ui.IndentationButtonTool.outdentListItem( this.toolbar.getSurfaceView().getModel() );
};

ve.ui.IndentationButtonTool.indentListItem = function ( surfaceModel ) {
	var i, group,
		documentModel = surfaceModel.getDocument(),
		selection = surfaceModel.getSelection(),
		groups = documentModel.getCoveredSiblingGroups( selection );

	function indentListItem( listItem ) {
		/*
		 * Indenting a list item is done as follows:
		 * 1. Wrap the listItem in a list and a listItem (<li> --> <li><ul><li>)
		 * 2. Merge this wrapped listItem into the previous listItem if present
		 *    (<li>Previous</li><li><ul><li>This --> <li>Previous<ul><li>This)
		 * 3. If this results in the wrapped list being preceded by another list,
		 *    merge those lists.
		 */
		var tx,
			listType = listItem.getParent().getAttribute( 'style' ),
			listItemRange = listItem.getOuterRange(),
			innerListItemRange,
			outerListItemRange,
			mergeStart,
			mergeEnd;

		// CAREFUL: after initializing the variables above, we cannot use the model tree!
		// The first transaction will cause rebuilds so the nodes we have references to now
		// will be detached and useless after the first transaction. Instead, inspect
		// documentModel.data to find out things about the current structure.

		// (1) Wrap the listItem in a list and a listItem
		tx = ve.dm.Transaction.newFromWrap( documentModel,
			listItemRange,
			[],
			[ { 'type': 'listItem' }, { 'type': 'list', 'attributes': { 'style': listType } } ],
			[],
			[]
		);
		surfaceModel.change( tx );
		selection = tx.translateRange( selection );
		// tx.translateRange( innerListItemRange ) doesn't do what we want
		innerListItemRange = ve.Range.newFromTranslatedRange( listItemRange, 2 );
		outerListItemRange = new ve.Range( listItemRange.start, listItemRange.end + 2 );

		// (2) Merge the listItem into the previous listItem (if there is one)
		if (
			documentModel.data[listItemRange.start].type === 'listItem' &&
			documentModel.data[listItemRange.start - 1].type === '/listItem'
		) {
			mergeStart = listItemRange.start - 1;
			mergeEnd = listItemRange.start + 1;
			// (3) If this results in adjacent lists, merge those too
			if (
				documentModel.data[mergeEnd].type === 'list' &&
				documentModel.data[mergeStart - 1].type === '/list'
			) {
				mergeStart--;
				mergeEnd++;
			}
			tx = ve.dm.Transaction.newFromRemoval( documentModel, new ve.Range( mergeStart, mergeEnd ) );
			surfaceModel.change( tx );
			selection = tx.translateRange( selection );
			innerListItemRange = tx.translateRange( innerListItemRange );
			outerListItemRange = tx.translateRange( outerListItemRange );
		}

		// TODO If this listItem has a child list, split&unwrap it

		surfaceModel.change( null, selection );
	}

	for ( i = 0; i < groups.length; i++ ) {
		group = groups[i];
		if ( group.grandparent && group.grandparent.getType() === 'list' ) {
			// FIXME this doesn't work when trying to work with multiple list items
			indentListItem( group.parent );
		}
	}
};

ve.ui.IndentationButtonTool.outdentListItem = function ( surfaceModel ) {
	var i, group,
		documentModel = surfaceModel.getDocument(),
		selection = surfaceModel.getSelection(),
		groups = documentModel.getCoveredSiblingGroups( selection );

	function outdentListItem( listItem ) {
		/*
		 * Outdenting a list item is done as follows:
		 * 1. Split the parent list to isolate the listItem in its own list
		 * 1a. Split the list before the listItem if it's not the first child
		 * 1b. Split the list after the listItem if it's not the last child
		 * 2. If this isolated list's parent is not a listItem, unwrap the listItem and the isolated list, and stop.
		 * 3. Split the parent listItem to isolate the list in its own listItem
		 * 3a. Split the listItem before the list if it's not the first child
		 * 3b. Split the listItem after the list if it's not the last child
		 * 4. Unwrap the now-isolated listItem and the isolated list
		 */
		// TODO child list handling, gotta figure that out
		var tx,
			list = listItem.getParent(),
			listType = list.getAttribute( 'style' ),
			listElement = list.getClonedElement(),
			grandParentType = list.getParent().getType(),
			listItemRange = listItem.getOuterRange(),
			splitListRange;

		// CAREFUL: after initializing the variables above, we cannot use the model tree!
		// The first transaction will cause rebuilds so the nodes we have references to now
		// will be detached and useless after the first transaction. Instead, inspect
		// documentModel.data to find out things about the current structure.

		// (1) Split the listItem into a separate list
		if ( documentModel.data[listItemRange.start - 1].type !== 'list' ) {
			// (1a) listItem is not the first child, split the list before listItem
			tx = ve.dm.Transaction.newFromInsertion( documentModel, listItemRange.start,
				[ { 'type': '/list' }, listElement ]
			);
			surfaceModel.change( tx );
			selection = tx.translateRange( selection );
			// tx.translateRange( listItemRange ) doesn't do what we want
			listItemRange = ve.Range.newFromTranslatedRange( listItemRange, 2 );
		}
		if ( documentModel.data[listItemRange.end].type !== '/list' ) {
			// (1b) listItem is not the last child, split the list after listItem
			tx = ve.dm.Transaction.newFromInsertion( documentModel, listItemRange.end,
				[ { 'type': '/list' }, listElement ]
			);
			surfaceModel.change( tx );
			selection = tx.translateRange( selection );
			// listItemRange is not affected by this transaction
		}
		splitListRange = new ve.Range( listItemRange.start - 1, listItemRange.end + 1 );

		if ( grandParentType !== 'listItem' ) {
			// The user is trying to unindent a list item that's not nested
			// (2) Unwrap both the list and the listItem, dumping the listItem's contents
			// into the list's parent
			tx = ve.dm.Transaction.newFromWrap( documentModel,
				new ve.Range( listItemRange.start + 1, listItemRange.end - 1 ),
				[ { 'type': 'list' }, { 'type': 'listItem' } ],
				[],
				[],
				[]
			);
			surfaceModel.change( tx );
			selection = tx.translateRange( selection );
		} else {
			// (3) Split the list away from parentListItem into its own listItem
			// TODO factor common split logic somehow?
			if ( documentModel.data[splitListRange.start - 1].type !== 'listItem' ) {
				// (3a) Split parentListItem before list
				tx = ve.dm.Transaction.newFromInsertion( documentModel, splitListRange.start,
					[ { 'type': '/listItem' }, { 'type': 'listItem' } ]
				);
				surfaceModel.change( tx );
				selection = tx.translateRange( selection );
				// tx.translateRange( splitListRange ) doesn't do what we want
				splitListRange = ve.Range.newFromTranslatedRange( splitListRange, 2 );
			}
			if ( documentModel.data[splitListRange.end].type !== '/listItem' ) {
				// (3b) Split parentListItem after list
				tx = ve.dm.Transaction.newFromInsertion( documentModel, splitListRange.end,
					[ { 'type': '/listItem' }, { 'type': 'listItem' } ]
				);
				surfaceModel.change( tx );
				selection = tx.translateRange( selection );
				// splitListRange is not affected by this transaction
			}

			// (4) Unwrap the list and its containing listItem
			tx = ve.dm.Transaction.newFromWrap( documentModel,
				new ve.Range( splitListRange.start + 1, splitListRange.end - 1 ),
				[ { 'type': 'listItem' }, { 'type': 'list' } ],
				[],
				[],
				[]
			);
			surfaceModel.change( tx );
			selection = tx.translateRange( selection );
		}

		surfaceModel.change( null, selection );
	}

	for ( i = 0; i < groups.length; i++ ) {
		group = groups[i];
		if ( group.grandparent && group.grandparent.getType() === 'list' ) {
			// FIXME this doesn't work when trying to work with multiple list items
			outdentListItem( group.parent );
		}
	}
};

ve.ui.IndentationButtonTool.prototype.updateState = function ( annotations, nodes ) {
	function areListItems( nodes ) {
		for ( var i = 0; i < nodes.length; i++ ) {
			if (
				nodes[i].parent !== null &&
				nodes[i].getParent().getType() !== 'listItem' )
			{
				return false;
			}
		}
		return true;
	}

	this.nodes = nodes;
	if ( areListItems( this.nodes ) ) {
		this.$.removeClass( 've-ui-toolbarButtonTool-disabled' );
	} else {
		this.$.addClass( 've-ui-toolbarButtonTool-disabled' );
	}
};

/* Registration */

ve.ui.Tool.tools.indent = {
	'constructor': ve.ui.IndentationButtonTool,
	'name': 'indent',
	'title': ve.msg( 'visualeditor-indentationbutton-indent-tooltip' )
};

ve.ui.Tool.tools.outdent = {
	'constructor': ve.ui.IndentationButtonTool,
	'name': 'outdent',
	'title': ve.msg( 'visualeditor-indentationbutton-outdent-tooltip' )
};