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 *       notice, this list of conditions and the following disclaimer.
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 *       names of its contributors may be used to endorse or promote products
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define(function (require, exports, module) {
    "use strict";

    var lang = require("../lib/lang");

    var TextHighlightRules = function () {

        // regexp must not have capturing parentheses
        // regexps are ordered -> the first match is used

        this.$rules = {
            "start": [{
                token: "empty_line",
                regex: '^$'
            }, {
                defaultToken: "text"
            }]
        };
    };

    (function () {

        this.addRules = function (rules, prefix) {
            if (!prefix) {
                for (var key in rules)
                    this.$rules[key] = rules[key];
                return;
            }
            for (var key in rules) {
                var state = rules[key];
                for (var i = 0; i < state.length; i++) {
                    var rule = state[i];
                    if (rule.next || rule.onMatch) {
                        if (typeof rule.next == "string") {
                            if (rule.next.indexOf(prefix) !== 0)
                                rule.next = prefix + rule.next;
                        }
                        if (rule.nextState && rule.nextState.indexOf(prefix) !== 0)
                            rule.nextState = prefix + rule.nextState;
                    }
                }
                this.$rules[prefix + key] = state;
            }
        };

        this.getRules = function () {
            return this.$rules;
        };

        this.embedRules = function (HighlightRules, prefix, escapeRules, states, append) {
            var embedRules = typeof HighlightRules == "function"
                ? new HighlightRules().getRules()
                : HighlightRules;
            if (states) {
                for (var i = 0; i < states.length; i++)
                    states[i] = prefix + states[i];
            } else {
                states = [];
                for (var key in embedRules)
                    states.push(prefix + key);
            }

            this.addRules(embedRules, prefix);

            if (escapeRules) {
                var addRules = Array.prototype[append ? "push" : "unshift"];
                for (var i = 0; i < states.length; i++)
                    addRules.apply(this.$rules[states[i]], lang.deepCopy(escapeRules));
            }

            if (!this.$embeds)
                this.$embeds = [];
            this.$embeds.push(prefix);
        };

        this.getEmbeds = function () {
            return this.$embeds;
        };

        var pushState = function (currentState, stack) {
            if (currentState != "start" || stack.length)
                stack.unshift(this.nextState, currentState);
            return this.nextState;
        };
        var popState = function (currentState, stack) {
            // if (stack[0] === currentState)
            stack.shift();
            return stack.shift() || "start";
        };

        this.normalizeRules = function () {
            var id = 0;
            var rules = this.$rules;

            function processState(key) {
                var state = rules[key];
                state.processed = true;
                for (var i = 0; i < state.length; i++) {
                    var rule = state[i];
                    var toInsert = null;
                    if (Array.isArray(rule)) {
                        toInsert = rule;
                        rule = {};
                    }
                    if (!rule.regex && rule.start) {
                        rule.regex = rule.start;
                        if (!rule.next)
                            rule.next = [];
                        rule.next.push({
                            defaultToken: rule.token
                        }, {
                            token: rule.token + ".end",
                            regex: rule.end || rule.start,
                            next: "pop"
                        });
                        rule.token = rule.token + ".start";
                        rule.push = true;
                    }
                    var next = rule.next || rule.push;
                    if (next && Array.isArray(next)) {
                        var stateName = rule.stateName;
                        if (!stateName) {
                            stateName = rule.token;
                            if (typeof stateName != "string")
                                stateName = stateName[0] || "";
                            if (rules[stateName])
                                stateName += id++;
                        }
                        rules[stateName] = next;
                        rule.next = stateName;
                        processState(stateName);
                    } else if (next == "pop") {
                        rule.next = popState;
                    }

                    if (rule.push) {
                        rule.nextState = rule.next || rule.push;
                        rule.next = pushState;
                        delete rule.push;
                    }

                    if (rule.rules) {
                        for (var r in rule.rules) {
                            if (rules[r]) {
                                if (rules[r].push)
                                    rules[r].push.apply(rules[r], rule.rules[r]);
                            } else {
                                rules[r] = rule.rules[r];
                            }
                        }
                    }
                    var includeName = typeof rule == "string"
                        ? rule
                        : typeof rule.include == "string"
                            ? rule.include
                            : "";
                    if (includeName) {
                        toInsert = rules[includeName];
                    }

                    if (toInsert) {
                        var args = [i, 1].concat(toInsert);
                        if (rule.noEscape)
                            args = args.filter(function (x) {
                                return !x.next;
                            });
                        state.splice.apply(state, args);
                        // skip included rules since they are already processed
                        //i += args.length - 3;
                        i--;
                    }

                    if (rule.keywordMap) {
                        rule.token = this.createKeywordMapper(
                            rule.keywordMap, rule.defaultToken || "text", rule.caseInsensitive
                        );
                        delete rule.defaultToken;
                    }
                }
            }

            Object.keys(rules).forEach(processState, this);
        };

        this.createKeywordMapper = function (map, defaultToken, ignoreCase, splitChar) {
            var keywords = Object.create(null);
            Object.keys(map).forEach(function (className) {
                var a = map[className];
                if (ignoreCase)
                    a = a.toLowerCase();
                var list = a.split(splitChar || "|");
                for (var i = list.length; i--;)
                    keywords[list[i]] = className;
            });
            // in old versions of opera keywords["__proto__"] sets prototype
            // even on objects with __proto__=null
            if (Object.getPrototypeOf(keywords)) {
                keywords.__proto__ = null;
            }
            this.$keywordList = Object.keys(keywords);
            map = null;
            return ignoreCase
                ? function (value) {
                    return keywords[value.toLowerCase()] || defaultToken
                }
                : function (value) {
                    return keywords[value] || defaultToken
                };
        };

        this.getKeywords = function () {
            return this.$keywords;
        };

    }).call(TextHighlightRules.prototype);

    exports.TextHighlightRules = TextHighlightRules;
});
