// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: http://codemirror.net/LICENSE

// LUA mode. Ported to CodeMirror 2 from Franciszek Wawrzak's
// CodeMirror 1 mode.
// highlights keywords, strings, comments (no leveling supported! ("[==[")), tokens, basic indenting

(function (mod) {
    if (typeof exports == "object" && typeof module == "object") // CommonJS
        mod(require("../../lib/codemirror"));
    else if (typeof define == "function" && define.amd) // AMD
        define(["../../lib/codemirror"], mod);
    else // Plain browser env
        mod(CodeMirror);
})(function (CodeMirror) {
    "use strict";

    CodeMirror.defineMode("lua", function (config, parserConfig) {
        var indentUnit = config.indentUnit;

        function prefixRE(words) {
            return new RegExp("^(?:" + words.join("|") + ")", "i");
        }

        function wordRE(words) {
            return new RegExp("^(?:" + words.join("|") + ")$", "i");
        }

        var specials = wordRE(parserConfig.specials || []);

        // long list of standard functions from lua manual
        var builtins = wordRE([
            "_G", "_VERSION", "assert", "collectgarbage", "dofile", "error", "getfenv", "getmetatable", "ipairs", "load",
            "loadfile", "loadstring", "module", "next", "pairs", "pcall", "print", "rawequal", "rawget", "rawset", "require",
            "select", "setfenv", "setmetatable", "tonumber", "tostring", "type", "unpack", "xpcall",

            "coroutine.create", "coroutine.resume", "coroutine.running", "coroutine.status", "coroutine.wrap", "coroutine.yield",

            "debug.debug", "debug.getfenv", "debug.gethook", "debug.getinfo", "debug.getlocal", "debug.getmetatable",
            "debug.getregistry", "debug.getupvalue", "debug.setfenv", "debug.sethook", "debug.setlocal", "debug.setmetatable",
            "debug.setupvalue", "debug.traceback",

            "close", "flush", "lines", "read", "seek", "setvbuf", "write",

            "io.close", "io.flush", "io.input", "io.lines", "io.open", "io.output", "io.popen", "io.read", "io.stderr", "io.stdin",
            "io.stdout", "io.tmpfile", "io.type", "io.write",

            "math.abs", "math.acos", "math.asin", "math.atan", "math.atan2", "math.ceil", "math.cos", "math.cosh", "math.deg",
            "math.exp", "math.floor", "math.fmod", "math.frexp", "math.huge", "math.ldexp", "math.log", "math.log10", "math.max",
            "math.min", "math.modf", "math.pi", "math.pow", "math.rad", "math.random", "math.randomseed", "math.sin", "math.sinh",
            "math.sqrt", "math.tan", "math.tanh",

            "os.clock", "os.date", "os.difftime", "os.execute", "os.exit", "os.getenv", "os.remove", "os.rename", "os.setlocale",
            "os.time", "os.tmpname",

            "package.cpath", "package.loaded", "package.loaders", "package.loadlib", "package.path", "package.preload",
            "package.seeall",

            "string.byte", "string.char", "string.dump", "string.find", "string.format", "string.gmatch", "string.gsub",
            "string.len", "string.lower", "string.match", "string.rep", "string.reverse", "string.sub", "string.upper",

            "table.concat", "table.insert", "table.maxn", "table.remove", "table.sort"
        ]);
        var keywords = wordRE(["and", "break", "elseif", "false", "nil", "not", "or", "return",
            "true", "function", "end", "if", "then", "else", "do",
            "while", "repeat", "until", "for", "in", "local"]);

        var indentTokens = wordRE(["function", "if", "repeat", "do", "\\(", "{"]);
        var dedentTokens = wordRE(["end", "until", "\\)", "}"]);
        var dedentPartial = prefixRE(["end", "until", "\\)", "}", "else", "elseif"]);

        function readBracket(stream) {
            var level = 0;
            while (stream.eat("=")) ++level;
            stream.eat("[");
            return level;
        }

        function normal(stream, state) {
            var ch = stream.next();
            if (ch == "-" && stream.eat("-")) {
                if (stream.eat("[") && stream.eat("["))
                    return (state.cur = bracketed(readBracket(stream), "comment"))(stream, state);
                stream.skipToEnd();
                return "comment";
            }
            if (ch == "\"" || ch == "'")
                return (state.cur = string(ch))(stream, state);
            if (ch == "[" && /[\[=]/.test(stream.peek()))
                return (state.cur = bracketed(readBracket(stream), "string"))(stream, state);
            if (/\d/.test(ch)) {
                stream.eatWhile(/[\w.%]/);
                return "number";
            }
            if (/[\w_]/.test(ch)) {
                stream.eatWhile(/[\w\\\-_.]/);
                return "variable";
            }
            return null;
        }

        function bracketed(level, style) {
            return function (stream, state) {
                var curlev = null, ch;
                while ((ch = stream.next()) != null) {
                    if (curlev == null) {
                        if (ch == "]") curlev = 0;
                    } else if (ch == "=") ++curlev;
                    else if (ch == "]" && curlev == level) {
                        state.cur = normal;
                        break;
                    } else curlev = null;
                }
                return style;
            };
        }

        function string(quote) {
            return function (stream, state) {
                var escaped = false, ch;
                while ((ch = stream.next()) != null) {
                    if (ch == quote && !escaped) break;
                    escaped = !escaped && ch == "\\";
                }
                if (!escaped) state.cur = normal;
                return "string";
            };
        }

        return {
            startState: function (basecol) {
                return {basecol: basecol || 0, indentDepth: 0, cur: normal};
            },

            token: function (stream, state) {
                if (stream.eatSpace()) return null;
                var style = state.cur(stream, state);
                var word = stream.current();
                if (style == "variable") {
                    if (keywords.test(word)) style = "keyword";
                    else if (builtins.test(word)) style = "builtin";
                    else if (specials.test(word)) style = "variable-2";
                }
                if ((style != "comment") && (style != "string")) {
                    if (indentTokens.test(word)) ++state.indentDepth;
                    else if (dedentTokens.test(word)) --state.indentDepth;
                }
                return style;
            },

            indent: function (state, textAfter) {
                var closing = dedentPartial.test(textAfter);
                return state.basecol + indentUnit * (state.indentDepth - (closing ? 1 : 0));
            },

            lineComment: "--",
            blockCommentStart: "--[[",
            blockCommentEnd: "]]"
        };
    });

    CodeMirror.defineMIME("text/x-lua", "lua");

});