/* TODO
	Handle multiline code after tag
	    %foo= some |
			multiline |
			code |
*/

(function(Prism) {

	Prism.languages.haml = {
		// Multiline stuff should appear before the rest

		'multiline-comment': [
			{
				pattern: /((?:^|\n)([\t ]*))\/.*(\n\2[\t ]+.+)*/,
				lookbehind: true,
				alias: 'comment'
			},
			{
				pattern: /((?:^|\n)([\t ]*))-#.*(\n\2[\t ]+.+)*/,
				lookbehind: true,
				alias: 'comment'
			}
		],

		'multiline-code': [
			{
				pattern: /((?:^|\n)([\t ]*)(?:[~-]|[&!]?=)).*,[\t ]*(\n\2[\t ]+.*,[\t ]*)*(\n\2[\t ]+.+)/,
				lookbehind: true,
				inside: {
					rest: Prism.languages.ruby
				}
			},
			{
				pattern: /((?:^|\n)([\t ]*)(?:[~-]|[&!]?=)).*\|[\t ]*(\n\2[\t ]+.*\|[\t ]*)*/,
				lookbehind: true,
				inside: {
					rest: Prism.languages.ruby
				}
			}
		],

		// See at the end of the file for known filters
		'filter': {
			pattern: /((?:^|\n)([\t ]*)):[\w-]+(\n(?:\2[\t ]+.+|\s*?(?=\n)))+/,
			lookbehind: true,
			inside: {
				'filter-name': {
					pattern: /^:[\w-]+/,
					alias: 'variable'
				}
			}
		},

		'markup': {
			pattern: /((?:^|\n)[\t ]*)<.+/,
			lookbehind: true,
			inside: {
				rest: Prism.languages.markup
			}
		},
		'doctype': {
			pattern: /((?:^|\n)[\t ]*)!!!(?: .+)?/,
			lookbehind: true
		},
		'tag': {
			// Allows for one nested group of braces
			pattern: /((?:^|\n)[\t ]*)[%.#][\w\-#.]*[\w\-](?:\([^)]+\)|\{(?:\{[^}]+\}|[^}])+\}|\[[^\]]+\])*[\/<>]*/,
			lookbehind: true,
			inside: {
				'attributes': [
					{
						// Lookbehind tries to prevent interpolations for breaking it all
						// Allows for one nested group of braces
						pattern: /(^|[^#])\{(?:\{[^}]+\}|[^}])+\}/,
						lookbehind: true,
						inside: {
							rest: Prism.languages.ruby
						}
					},
					{
						pattern: /\([^)]+\)/,
						inside: {
							'attr-value': {
								pattern: /(=\s*)(?:"(?:\\?.)*?"|[^)\s]+)/,
								lookbehind: true
							},
							'attr-name': /[\w:-]+(?=\s*!?=|\s*[,)])/,
							'punctuation': /[=(),]/
						}
					},
					{
						pattern: /\[[^\]]+\]/,
						inside: {
							rest: Prism.languages.ruby
						}
					}
				],
				'punctuation': /[<>]/
			}
		},
		'code': {
			pattern: /((?:^|\n)[\t ]*(?:[~-]|[&!]?=)).+/,
			lookbehind: true,
			inside: {
				rest: Prism.languages.ruby
			}
		},
		// Interpolations in plain text
		'interpolation': {
			pattern: /#\{[^}]+\}/,
			inside: {
				'delimiter': {
					pattern: /^#\{|\}$/,
					alias: 'punctuation'
				},
				rest: Prism.languages.ruby
			}
		},
		'punctuation': {
			pattern: /((?:^|\n)[\t ]*)[~=\-&!]/,
			lookbehind: true
		}
	};

	var filter_pattern = '((?:^|\\n)([\\t ]*)):{{filter_name}}(\\n(?:\\2[\\t ]+.+|\\s*?(?=\\n)))+';

	// Non exhaustive list of available filters and associated languages
	var filters = [
		'css',
		{filter:'coffee',language:'coffeescript'},
		'erb',
		'javascript',
		'less',
		'markdown',
		'ruby',
		'scss',
		'textile'
	];
	var all_filters = {};
	for (var i = 0, l = filters.length; i < l; i++) {
		var filter = filters[i];
		filter = typeof filter === 'string' ? {filter: filter, language: filter} : filter;
		if (Prism.languages[filter.language]) {
			all_filters['filter-' + filter.filter] = {
				pattern: RegExp(filter_pattern.replace('{{filter_name}}', filter.filter)),
				lookbehind: true,
				inside: {
					'filter-name': {
						pattern: /^:[\w-]+/,
						alias: 'variable'
					},
					rest: Prism.languages[filter.language]
				}
			}
		}
	}

	Prism.languages.insertBefore('haml', 'filter', all_filters);

}(Prism));