/*!
 * VisualEditor DataModel MWWikitextSurfaceFragment class.
 *
 * @copyright 2011-2016 VisualEditor Team and others; see http://ve.mit-license.org
 */

/**
 * DataModel MWWikitextSurfaceFragment.
 *
 * @class
 * @extends ve.dm.SourceSurfaceFragment
 *
 * @constructor
 * @param {ve.dm.Document} doc
 */
ve.dm.MWWikitextSurfaceFragment = function VeDmMwWikitextSurfaceFragment() {
	// Parent constructors
	ve.dm.MWWikitextSurfaceFragment.super.apply( this, arguments );
};

/* Inheritance */

OO.inheritClass( ve.dm.MWWikitextSurfaceFragment, ve.dm.SourceSurfaceFragment );

/**
 * Wrap a text selection.
 *
 * If the selection is already identically wrapped it will be unwrapped.
 *
 * @param {string} before Text to go before selection
 * @param {string} after Text to go after selection
 * @param {Function|string} placeholder Placeholder text to insert at an empty selection
 * @param {boolean} forceWrap Force wrapping, even if matching wrapping exists
 * @chainable
 */
ve.dm.MWWikitextSurfaceFragment.prototype.wrapText = function ( before, after, placeholder, forceWrap ) {
	var wrappedFragment, wasExcludingInsertions;

	placeholder = OO.ui.resolveMsg( placeholder );

	function unwrap( fragment ) {
		var text = fragment.getText();
		if (
			( !before || text.slice( 0, before.length ) === before ) &&
			( !after || text.slice( -after.length ) === after )
		) {
			fragment.unwrapText( before.length, after.length );
			// Just the placeholder left, nothing meaningful was selected so just remove it
			if ( fragment.getText() === placeholder ) {
				fragment.removeContent();
			}
			return true;
		}
		return false;
	}

	if ( !forceWrap && ( unwrap( this ) || unwrap( this.adjustLinearSelection( -before.length, after.length ) ) ) ) {
		return this;
	} else {
		if ( placeholder && this.getSelection().isCollapsed() ) {
			this.insertContent( placeholder );
		}
		wrappedFragment = this.clone();
		wasExcludingInsertions = this.willExcludeInsertions();
		this.setExcludeInsertions( true );
		this.collapseToStart().insertContent( before );
		this.collapseToEnd().insertContent( after );
		this.setExcludeInsertions( wasExcludingInsertions );
		return wrappedFragment;
	}
};

/**
 * Unwrap a fixed amount of text
 *
 * @param {number} before Amount of text to remove from start
 * @param {number} after Amount of text to remove from end
 * @chainable
 */
ve.dm.MWWikitextSurfaceFragment.prototype.unwrapText = function ( before, after ) {
	this.collapseToStart().adjustLinearSelection( 0, before ).removeContent();
	this.collapseToEnd().adjustLinearSelection( -after, 0 ).removeContent();
	return this;
};

/**
 * @inheritdoc
 */
ve.dm.MWWikitextSurfaceFragment.prototype.convertDocument = function ( doc ) {
	var wikitextPromise;

	if ( !doc.data.hasContent() ) {
		return $.Deferred().reject().promise();
	}

	wikitextPromise = ve.init.target.getWikitextFragment( doc, false );

	// TODO: Emit an event to trigger the progress bar
	ve.init.target.getSurface().createProgress(
		wikitextPromise, ve.msg( 'visualeditor-generating-wikitext-progress' )
	).done( function ( progressBar, cancelPromise ) {
		cancelPromise.fail( function () {
			wikitextPromise.abort();
		} );
	} );

	return wikitextPromise;
};