/**
 * ECharts option manager
 *
 * @module {echarts/model/OptionManager}
 */

define(function (require) {

    var zrUtil = require('zrender/core/util');
    var modelUtil = require('../util/model');
    var ComponentModel = require('./Component');
    var each = zrUtil.each;
    var clone = zrUtil.clone;
    var map = zrUtil.map;
    var merge = zrUtil.merge;

    var QUERY_REG = /^(min|max)?(.+)$/;

    /**
     * TERM EXPLANATIONS:
     *
     * [option]:
     *
     *     An object that contains definitions of components. For example:
     *     var option = {
     *         title: {...},
     *         legend: {...},
     *         visualMap: {...},
     *         series: [
     *             {data: [...]},
     *             {data: [...]},
     *             ...
     *         ]
     *     };
     *
     * [rawOption]:
     *
     *     An object input to echarts.setOption. 'rawOption' may be an
     *     'option', or may be an object contains multi-options. For example:
     *     var option = {
     *         baseOption: {
     *             title: {...},
     *             legend: {...},
     *             series: [
     *                 {data: [...]},
     *                 {data: [...]},
     *                 ...
     *             ]
     *         },
     *         timeline: {...},
     *         options: [
     *             {title: {...}, series: {data: [...]}},
     *             {title: {...}, series: {data: [...]}},
     *             ...
     *         ],
     *         media: [
     *             {
     *                 query: {maxWidth: 320},
     *                 option: {series: {x: 20}, visualMap: {show: false}}
     *             },
     *             {
     *                 query: {minWidth: 320, maxWidth: 720},
     *                 option: {series: {x: 500}, visualMap: {show: true}}
     *             },
     *             {
     *                 option: {series: {x: 1200}, visualMap: {show: true}}
     *             }
     *         ]
     *     };
     *
     * @alias module:echarts/model/OptionManager
     * @param {module:echarts/ExtensionAPI} api
     */
    function OptionManager(api) {

        /**
         * @private
         * @type {module:echarts/ExtensionAPI}
         */
        this._api = api;

        /**
         * @private
         * @type {Array.<number>}
         */
        this._timelineOptions = [];

        /**
         * @private
         * @type {Array.<Object>}
         */
        this._mediaList = [];

        /**
         * @private
         * @type {Object}
         */
        this._mediaDefault;

        /**
         * -1, means default.
         * empty means no media.
         * @private
         * @type {Array.<number>}
         */
        this._currentMediaIndices = [];

        /**
         * @private
         * @type {Object}
         */
        this._optionBackup;

        /**
         * @private
         * @type {Object}
         */
        this._newBaseOption;
    }

    // timeline.notMerge is not supported in ec3. Firstly there is rearly
    // case that notMerge is needed. Secondly supporting 'notMerge' requires
    // rawOption cloned and backuped when timeline changed, which does no
    // good to performance. What's more, that both timeline and setOption
    // method supply 'notMerge' brings complex and some problems.
    // Consider this case:
    // (step1) chart.setOption({timeline: {notMerge: false}, ...}, false);
    // (step2) chart.setOption({timeline: {notMerge: true}, ...}, false);

    OptionManager.prototype = {

        constructor: OptionManager,

        /**
         * @public
         * @param {Object} rawOption Raw option.
         * @param {module:echarts/model/Global} ecModel
         * @param {Array.<Function>} optionPreprocessorFuncs
         * @return {Object} Init option
         */
        setOption: function (rawOption, optionPreprocessorFuncs) {
            rawOption = clone(rawOption, true);

            // FIXME
            // 如果 timeline options 或者 media 中设置了某个属性，而baseOption中没有设置，则进行警告。

            var oldOptionBackup = this._optionBackup;
            var newParsedOption = parseRawOption.call(
                this, rawOption, optionPreprocessorFuncs
            );
            this._newBaseOption = newParsedOption.baseOption;

            // For setOption at second time (using merge mode);
            if (oldOptionBackup) {
                // Only baseOption can be merged.
                mergeOption(oldOptionBackup.baseOption, newParsedOption.baseOption);

                // For simplicity, timeline options and media options do not support merge,
                // that is, if you `setOption` twice and both has timeline options, the latter
                // timeline opitons will not be merged to the formers, but just substitude them.
                if (newParsedOption.timelineOptions.length) {
                    oldOptionBackup.timelineOptions = newParsedOption.timelineOptions;
                }
                if (newParsedOption.mediaList.length) {
                    oldOptionBackup.mediaList = newParsedOption.mediaList;
                }
                if (newParsedOption.mediaDefault) {
                    oldOptionBackup.mediaDefault = newParsedOption.mediaDefault;
                }
            }
            else {
                this._optionBackup = newParsedOption;
            }
        },

        /**
         * @param {boolean} isRecreate
         * @return {Object}
         */
        mountOption: function (isRecreate) {
            var optionBackup = this._optionBackup;

            // TODO
            // 如果没有reset功能则不clone。

            this._timelineOptions = map(optionBackup.timelineOptions, clone);
            this._mediaList = map(optionBackup.mediaList, clone);
            this._mediaDefault = clone(optionBackup.mediaDefault);
            this._currentMediaIndices = [];

            return clone(isRecreate
                // this._optionBackup.baseOption, which is created at the first `setOption`
                // called, and is merged into every new option by inner method `mergeOption`
                // each time `setOption` called, can be only used in `isRecreate`, because
                // its reliability is under suspicion. In other cases option merge is
                // proformed by `model.mergeOption`.
                ? optionBackup.baseOption : this._newBaseOption
            );
        },

        /**
         * @param {module:echarts/model/Global} ecModel
         * @return {Object}
         */
        getTimelineOption: function (ecModel) {
            var option;
            var timelineOptions = this._timelineOptions;

            if (timelineOptions.length) {
                // getTimelineOption can only be called after ecModel inited,
                // so we can get currentIndex from timelineModel.
                var timelineModel = ecModel.getComponent('timeline');
                if (timelineModel) {
                    option = clone(
                        timelineOptions[timelineModel.getCurrentIndex()],
                        true
                    );
                }
            }

            return option;
        },

        /**
         * @param {module:echarts/model/Global} ecModel
         * @return {Array.<Object>}
         */
        getMediaOption: function (ecModel) {
            var ecWidth = this._api.getWidth();
            var ecHeight = this._api.getHeight();
            var mediaList = this._mediaList;
            var mediaDefault = this._mediaDefault;
            var indices = [];
            var result = [];

            // No media defined.
            if (!mediaList.length && !mediaDefault) {
                return result;
            }

            // Multi media may be applied, the latter defined media has higher priority.
            for (var i = 0, len = mediaList.length; i < len; i++) {
                if (applyMediaQuery(mediaList[i].query, ecWidth, ecHeight)) {
                    indices.push(i);
                }
            }

            // FIXME
            // 是否mediaDefault应该强制用户设置，否则可能修改不能回归。
            if (!indices.length && mediaDefault) {
                indices = [-1];
            }

            if (indices.length && !indicesEquals(indices, this._currentMediaIndices)) {
                result = map(indices, function (index) {
                    return clone(
                        index === -1 ? mediaDefault.option : mediaList[index].option
                    );
                });
            }
            // Otherwise return nothing.

            this._currentMediaIndices = indices;

            return result;
        }
    };

    function parseRawOption(rawOption, optionPreprocessorFuncs) {
        var timelineOptions = [];
        var mediaList = [];
        var mediaDefault;
        var baseOption;

        // Compatible with ec2.
        var timelineOpt = rawOption.timeline;

        if (rawOption.baseOption) {
            baseOption = rawOption.baseOption;
        }

        // For timeline
        if (timelineOpt || rawOption.options) {
            baseOption = baseOption || {};
            timelineOptions = (rawOption.options || []).slice();
        }

        // For media query
        if (rawOption.media) {
            baseOption = baseOption || {};
            var media = rawOption.media;
            each(media, function (singleMedia) {
                if (singleMedia && singleMedia.option) {
                    if (singleMedia.query) {
                        mediaList.push(singleMedia);
                    }
                    else if (!mediaDefault) {
                        // Use the first media default.
                        mediaDefault = singleMedia;
                    }
                }
            });
        }

        // For normal option
        if (!baseOption) {
            baseOption = rawOption;
        }

        // Set timelineOpt to baseOption in ec3,
        // which is convenient for merge option.
        if (!baseOption.timeline) {
            baseOption.timeline = timelineOpt;
        }

        // Preprocess.
        each([baseOption].concat(timelineOptions)
            .concat(zrUtil.map(mediaList, function (media) {
                return media.option;
            })),
            function (option) {
                each(optionPreprocessorFuncs, function (preProcess) {
                    preProcess(option);
                });
            }
        );

        return {
            baseOption: baseOption,
            timelineOptions: timelineOptions,
            mediaDefault: mediaDefault,
            mediaList: mediaList
        };
    }

    /**
     * @see <http://www.w3.org/TR/css3-mediaqueries/#media1>
     * Support: width, height, aspectRatio
     * Can use max or min as prefix.
     */
    function applyMediaQuery(query, ecWidth, ecHeight) {
        var realMap = {
            width: ecWidth,
            height: ecHeight,
            aspectratio: ecWidth / ecHeight // lowser case for convenientce.
        };

        var applicatable = true;

        zrUtil.each(query, function (value, attr) {
            var matched = attr.match(QUERY_REG);

            if (!matched || !matched[1] || !matched[2]) {
                return;
            }

            var operator = matched[1];
            var realAttr = matched[2].toLowerCase();

            if (!compare(realMap[realAttr], value, operator)) {
                applicatable = false;
            }
        });

        return applicatable;
    }

    function compare(real, expect, operator) {
        if (operator === 'min') {
            return real >= expect;
        }
        else if (operator === 'max') {
            return real <= expect;
        }
        else { // Equals
            return real === expect;
        }
    }

    function indicesEquals(indices1, indices2) {
        // indices is always order by asc and has only finite number.
        return indices1.join(',') === indices2.join(',');
    }

    /**
     * Consider case:
     * `chart.setOption(opt1);`
     * Then user do some interaction like dataZoom, dataView changing.
     * `chart.setOption(opt2);`
     * Then user press 'reset button' in toolbox.
     *
     * After doing that all of the interaction effects should be reset, the
     * chart should be the same as the result of invoke
     * `chart.setOption(opt1); chart.setOption(opt2);`.
     *
     * Although it is not able ensure that
     * `chart.setOption(opt1); chart.setOption(opt2);` is equivalents to
     * `chart.setOption(merge(opt1, opt2));` exactly,
     * this might be the only simple way to implement that feature.
     *
     * MEMO: We've considered some other approaches:
     * 1. Each model handle its self restoration but not uniform treatment.
     *     (Too complex in logic and error-prone)
     * 2. Use a shadow ecModel. (Performace expensive)
     */
    function mergeOption(oldOption, newOption) {
        newOption = newOption || {};

        each(newOption, function (newCptOpt, mainType) {
            if (newCptOpt == null) {
                return;
            }

            var oldCptOpt = oldOption[mainType];

            if (!ComponentModel.hasClass(mainType)) {
                oldOption[mainType] = merge(oldCptOpt, newCptOpt, true);
            }
            else {
                newCptOpt = modelUtil.normalizeToArray(newCptOpt);
                oldCptOpt = modelUtil.normalizeToArray(oldCptOpt);

                var mapResult = modelUtil.mappingToExists(oldCptOpt, newCptOpt);

                oldOption[mainType] = map(mapResult, function (item) {
                    return (item.option && item.exist)
                        ? merge(item.exist, item.option, true)
                        : (item.exist || item.option);
                });
            }
        });
    }

    return OptionManager;
});