define(['jquery', 'bootstrap', 'backend', 'table', 'form', 'backend/format'], function ($, undefined, Backend, Table, Form, Format) {

    var Controller = {
        /**
         * 服务区域列表页初始化
         */
        index: function () {
            // 初始化表格参数配置
            Table.api.init({
                extend: {
                    index_url: 'fc/area/index' + location.search,
                    add_url: 'fc/area/add',
                    edit_url: 'fc/area/edit',
                    del_url: 'fc/area/del',
                    multi_url: 'fc/area/multi',
                    import_url: 'fc/area/import',
                    table: 'fc_area',
                }
            });

            var table = $("#table");

            // 初始化表格
            table.bootstrapTable({
                url: $.fn.bootstrapTable.defaults.extend.index_url,
                pk: 'id',
                sortName: 'sort',
                columns: [
                    [
                        {checkbox: true},
                        {field: 'id', title: __('SerialNo'), operate: false, sortable: false, align: 'center', width: '70px', class: 'fc-serial', table: table, formatter: Format.serial},
                        {field: 'province', title: __('Province'), operate: 'LIKE'},
                        {field: 'city', title: __('City'), operate: 'LIKE'},
                        {field: 'district', title: __('District'), operate: 'LIKE'},
                        {field: 'full_name', title: __('FullName'), operate: false, sortable: false},
                        {
                            field: 'enabled', title: __('Enabled'),
                            searchList: {0: '否', 1: '是'},
                            formatter: Format.statusFormatter({0: '否', 1: '是'}, {0: 'default', 1: 'success'})
                        },
                        {field: 'sort', title: __('Sort'), width: '80px'},
                        {field: 'lat', title: __('Lat'), operate: false, visible: false},
                        {field: 'lng', title: __('Lng'), operate: false, visible: false},
                        {field: 'createtime', title: __('Createtime'), operate: 'RANGE', addclass: 'datetimerange', autocomplete: false, formatter: Table.api.formatter.datetime},
                        {field: 'updatetime', title: __('Updatetime'), operate: 'RANGE', addclass: 'datetimerange', autocomplete: false, formatter: Table.api.formatter.datetime, visible: false},
                        {field: 'operate', title: __('Operate'), table: table, events: Table.api.events.operate, formatter: Table.api.formatter.operate}
                    ]
                ]
            });

            // 为表格绑定事件
            Table.api.bindevent(table);
        },

        /**
         * 服务区域新增页初始化
         */
        add: function () {
            Controller.api.bindevent();
            Controller.api.bindAreaOptions();
        },

        /**
         * 服务区域编辑页初始化
         */
        edit: function () {
            Controller.api.bindevent();
            Controller.api.bindAreaOptions();
        },

        api: {
            /**
             * 绑定表单通用事件
             */
            bindevent: function () {
                Form.api.bindevent($("form[role=form]"));
            },

            /**
             * 规范化省级名称（将直辖市简称统一为标准全称）
             * @param {string} name 原始省份名称
             * @return {string}
             */
            normalizeProvinceName: function (name) {
                var val = String(name || '').trim();
                var map = {
                    '北京': '北京市',
                    '天津': '天津市',
                    '上海': '上海市',
                    '重庆': '重庆市',
                    '台湾': '台湾省'
                };
                return map[val] || val;
            },

            /**
             * 加载全国行政区划数据（ChineseDistricts）
             * @param {function} callback 数据加载完成回调
             */
            loadNationalDistricts: function (callback) {
                if (typeof window !== 'undefined' && window.ChineseDistricts) {
                    callback(window.ChineseDistricts);
                    return;
                }
                require(['citypicker-data'], function () {
                    if (typeof window !== 'undefined' && window.ChineseDistricts) {
                        callback(window.ChineseDistricts);
                        return;
                    }
                    require(['ChineseDistricts'], function (ChineseDistricts) {
                        callback(ChineseDistricts || window.ChineseDistricts || {});
                    }, function () {
                        callback({});
                    });
                }, function () {
                    callback({});
                });
            },

            /**
             * 构建全国省 / 市 / 区县全量数据树并合并数据库已有记录
             * @param {Object} chineseDistricts 全国行政区划原始字典
             * @param {Array} dbRows 数据库已存服务区域记录
             * @param {number} currentId 当前编辑记录ID（新增时为0）
             * @return {Object} 包含 provinces, cityMap, districtMap, allCities, allDistricts, addedMap
             */
            buildAreaDataTree: function (chineseDistricts, dbRows, currentId) {
                var normalizeProvince = Controller.api.normalizeProvinceName;
                var provinces = [];
                var provinceSeen = {};
                var cityMap = {};
                var districtMap = {};
                var addedMap = {};

                /**
                 * 确保省份存在于数据树中
                 * @param {string} prov 省份名称
                 */
                var ensureProvince = function (prov) {
                    var p = normalizeProvince(prov);
                    if (!p) {
                        return '';
                    }
                    if (!provinceSeen[p]) {
                        provinceSeen[p] = true;
                        provinces.push(p);
                    }
                    if (!cityMap[p]) {
                        cityMap[p] = [];
                    }
                    return p;
                };

                /**
                 * 确保城市存在于指定省份下
                 * @param {string} prov 省份名称
                 * @param {string} city 城市名称
                 */
                var ensureCity = function (prov, city) {
                    var p = ensureProvince(prov);
                    var c = String(city || '').trim();
                    if (!p || !c) {
                        return;
                    }
                    if (cityMap[p].indexOf(c) === -1) {
                        cityMap[p].push(c);
                    }
                    var key = p + '|' + c;
                    if (!districtMap[key]) {
                        districtMap[key] = [];
                    }
                };

                /**
                 * 确保区县存在于指定省市下
                 * @param {string} prov 省份名称
                 * @param {string} city 城市名称
                 * @param {string} dist 区县名称
                 */
                var ensureDistrict = function (prov, city, dist) {
                    var p = ensureProvince(prov);
                    var c = String(city || '').trim();
                    var d = String(dist || '').trim();
                    if (!p || !c || !d) {
                        return;
                    }
                    ensureCity(p, c);
                    var key = p + '|' + c;
                    if (districtMap[key].indexOf(d) === -1) {
                        districtMap[key].push(d);
                    }
                };

                // 1. 解析全国行政区划库 ChineseDistricts
                if (chineseDistricts && chineseDistricts[86]) {
                    var groups = chineseDistricts[86];
                    var provEntries = [];
                    $.each(groups, function (groupKey, list) {
                        if ($.isArray(list)) {
                            for (var i = 0; i < list.length; i++) {
                                if (list[i] && list[i].code && list[i].address) {
                                    provEntries.push(list[i]);
                                }
                            }
                        }
                    });
                    // 按行政区划代码排序（北京、天津、河北...顺序更符合国标习惯）
                    provEntries.sort(function (a, b) {
                        return String(a.code).localeCompare(String(b.code));
                    });

                    for (var i = 0; i < provEntries.length; i++) {
                        var provCode = provEntries[i].code;
                        var provName = ensureProvince(provEntries[i].address);
                        var citiesObj = chineseDistricts[provCode];
                        if (citiesObj && $.isPlainObject(citiesObj)) {
                            $.each(citiesObj, function (cityCode, cityName) {
                                ensureCity(provName, cityName);
                                var districtsObj = chineseDistricts[cityCode];
                                if (districtsObj && $.isPlainObject(districtsObj)) {
                                    $.each(districtsObj, function (distCode, distName) {
                                        ensureDistrict(provName, cityName, distName);
                                    });
                                }
                            });
                        }
                    }
                }

                // 2. 合并数据库已有的 fc_area 记录（兼顾自定义区域与已添加标记）
                if ($.isArray(dbRows)) {
                    for (var j = 0; j < dbRows.length; j++) {
                        var row = dbRows[j] || {};
                        var pRaw = String(row.province || '').trim();
                        var pNorm = normalizeProvince(pRaw);
                        var cName = String(row.city || '').trim();
                        var dName = String(row.district || '').trim();
                        var rowId = parseInt(row.id || 0, 10);

                        if (pNorm && cName && dName) {
                            ensureDistrict(pNorm, cName, dName);
                            if (rowId !== currentId) {
                                addedMap[pNorm + '|' + cName + '|' + dName] = true;
                                addedMap[pRaw + '|' + cName + '|' + dName] = true;
                            }
                        }
                    }
                }

                // 3. 构建全国扁平化城市索引与区县索引，支持跨省直搜城市/区县反填
                var allCities = [];
                var allDistricts = [];
                for (var pIdx = 0; pIdx < provinces.length; pIdx++) {
                    var pItem = provinces[pIdx];
                    var cList = cityMap[pItem] || [];
                    for (var cIdx = 0; cIdx < cList.length; cIdx++) {
                        var cItem = cList[cIdx];
                        allCities.push({
                            province: pItem,
                            city: cItem
                        });
                        var dList = districtMap[pItem + '|' + cItem] || [];
                        for (var dIdx = 0; dIdx < dList.length; dIdx++) {
                            allDistricts.push({
                                province: pItem,
                                city: cItem,
                                district: dList[dIdx]
                            });
                        }
                    }
                }

                return {
                    provinces: provinces,
                    cityMap: cityMap,
                    districtMap: districtMap,
                    allCities: allCities,
                    allDistricts: allDistricts,
                    addedMap: addedMap
                };
            },

            /**
             * 省 / 市 / 区县全量可搜索级联下拉与中心坐标联动
             */
            bindAreaOptions: function () {
                var $raw = $('#area-options');
                var $province = $('#c-province');
                var $city = $('#c-city');
                var $district = $('#c-district');
                var $lat = $('#c-lat');
                var $lng = $('#c-lng');
                if (!$raw.length || !$province.length) {
                    return;
                }

                var currentId = parseInt($raw.data('current-id') || 0, 10);
                var dbRows = [];
                try {
                    dbRows = JSON.parse($raw.val() || '[]');
                } catch (e) {
                    dbRows = [];
                }
                if (!$.isArray(dbRows)) {
                    dbRows = [];
                }

                var normalizeProvince = Controller.api.normalizeProvinceName;
                var coordAutoFilled = false;
                var geocodeTimer = null;

                /**
                 * 更新输入框包装容器的 has-value 状态（控制清空按钮显示）
                 */
                var syncWrapState = function () {
                    $('.fc-area-select-wrap').each(function () {
                        var $wrap = $(this);
                        var val = String($wrap.find('.fc-area-input').val() || '').trim();
                        $wrap.toggleClass('has-value', val !== '');
                    });
                };

                /**
                 * 将 WGS84 坐标转换为 GCJ02 坐标（中国大陆标准）
                 * @param {number} wgsLng WGS84经度
                 * @param {number} wgsLat WGS84纬度
                 * @return {{lat: number, lng: number}}
                 */
                var wgs84ToGcj02 = function (wgsLng, wgsLat) {
                    var lon = Number(wgsLng);
                    var lat = Number(wgsLat);
                    if (!isFinite(lon) || !isFinite(lat)) {
                        return {lat: lat, lng: lon};
                    }
                    var a = 6378245.0;
                    var ee = 0.00669342162296594323;
                    var pi = Math.PI;
                    var transformLat = function (x, y) {
                        var ret = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y + 0.2 * Math.sqrt(Math.abs(x));
                        ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;
                        ret += (20.0 * Math.sin(y * pi) + 40.0 * Math.sin(y / 3.0 * pi)) * 2.0 / 3.0;
                        ret += (160.0 * Math.sin(y / 12.0 * pi) + 320 * Math.sin(y * pi / 30.0)) * 2.0 / 3.0;
                        return ret;
                    };
                    var transformLon = function (x, y) {
                        var ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1 * Math.sqrt(Math.abs(x));
                        ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;
                        ret += (20.0 * Math.sin(x * pi) + 40.0 * Math.sin(x / 3.0 * pi)) * 2.0 / 3.0;
                        ret += (150.0 * Math.sin(x / 12.0 * pi) + 300.0 * Math.sin(x / 30.0 * pi)) * 2.0 / 3.0;
                        return ret;
                    };
                    var dLat = transformLat(lon - 105.0, lat - 35.0);
                    var dLon = transformLon(lon - 105.0, lat - 35.0);
                    var radLat = lat / 180.0 * pi;
                    var magic = Math.sin(radLat);
                    magic = 1 - ee * magic * magic;
                    var sqrtMagic = Math.sqrt(magic);
                    dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
                    dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);
                    return {
                        lat: lat + dLat,
                        lng: lon + dLon
                    };
                };

                /**
                 * 刷新完整区域实时预览文案并同步地图选点按钮默认地址
                 */
                var refreshPreview = function () {
                    var parts = [
                        String($province.val() || '').trim(),
                        String($city.val() || '').trim(),
                        String($district.val() || '').trim()
                    ].filter(function (item) {
                        return item !== '';
                    });
                    $('#area-full-name').text(parts.length ? parts.join(' / ') : '未选择');
                    $('.fc-area-map-btn').data('address', parts.join(''));
                    syncWrapState();
                };

                /**
                 * 刷新中心坐标状态提示文案
                 * @param {boolean} isAuto 是否为自动匹配填充
                 */
                var refreshCoordTip = function (isAuto) {
                    var lat = String($lat.val() || '').trim();
                    var lng = String($lng.val() || '').trim();
                    var $tip = $('#area-coord-tip');
                    if (lat && lng && isFinite(lat) && isFinite(lng)) {
                        var prefix = isAuto ? '已根据所选区域自动匹配中心坐标：' : '已设置中心坐标：';
                        $tip.removeClass('is-missing').addClass('is-set')
                            .text(prefix + lat + ', ' + lng + '（可点击「地图选点」微调）');
                    } else {
                        $tip.removeClass('is-set').addClass('is-missing')
                            .text('未设置坐标：选择区域后将自动匹配中心坐标，也可点击「地图选点」手动指定');
                    }
                };

                /**
                 * 根据所选省市区自动解析中心经纬度（腾讯Place接口 + Nominatim自动降级）
                 */
                var autoResolveCoordinates = function () {
                    var p = String($province.val() || '').trim();
                    var c = String($city.val() || '').trim();
                    var d = String($district.val() || '').trim();
                    if (!p || !c || !d) {
                        return;
                    }

                    var curLat = String($lat.val() || '').trim();
                    var curLng = String($lng.val() || '').trim();
                    // 若已有手动填写的坐标且非自动匹配产生，则不覆盖
                    if (curLat && curLng && !coordAutoFilled) {
                        return;
                    }

                    if (geocodeTimer) {
                        clearTimeout(geocodeTimer);
                    }
                    geocodeTimer = setTimeout(function () {
                        var queryAddress = (p === c ? p : (p + ' ' + c)) + ' ' + d;
                        var resolveByNominatim = function () {
                            $.ajax({
                                url: 'https://nominatim.openstreetmap.org/search',
                                dataType: 'jsonp',
                                jsonp: 'json_callback',
                                data: {
                                    format: 'json',
                                    q: queryAddress,
                                    limit: 1,
                                    'accept-language': 'zh-CN',
                                    countrycodes: 'cn'
                                },
                                success: function (list) {
                                    if ($.isArray(list) && list.length > 0 && list[0].lat && list[0].lon) {
                                        var gcj = wgs84ToGcj02(list[0].lon, list[0].lat);
                                        coordAutoFilled = true;
                                        $lat.val(Number(gcj.lat).toFixed(6));
                                        $lng.val(Number(gcj.lng).toFixed(6));
                                        refreshCoordTip(true);
                                    }
                                }
                            });
                        };

                        var tencentKey = 'WM7BZ-ZAYLL-MZEPZ-MRZBT-MBYJE-ZAFIT';
                        $.ajax({
                            url: 'https://apis.map.qq.com/ws/place/v1/suggestion',
                            dataType: 'jsonp',
                            data: {
                                keyword: (p === c ? p : (p + c)) + d,
                                region: c,
                                key: tencentKey,
                                output: 'jsonp'
                            },
                            success: function (ret) {
                                if (ret && ret.status === 0 && $.isArray(ret.data) && ret.data.length > 0 && ret.data[0].location) {
                                    var loc = ret.data[0].location;
                                    if (loc.lat && loc.lng) {
                                        coordAutoFilled = true;
                                        $lat.val(Number(loc.lat).toFixed(6));
                                        $lng.val(Number(loc.lng).toFixed(6));
                                        refreshCoordTip(true);
                                        return;
                                    }
                                }
                                resolveByNominatim();
                            },
                            error: function () {
                                resolveByNominatim();
                            }
                        });
                    }, 180);
                };

                refreshPreview();
                refreshCoordTip(false);

                // 手动修改坐标时标记为非自动填充
                $lat.add($lng).on('input change', function () {
                    coordAutoFilled = false;
                    refreshCoordTip(false);
                });

                // 加载全国省市区数据并绑定下拉交互
                Controller.api.loadNationalDistricts(function (chineseDistricts) {
                    var tree = Controller.api.buildAreaDataTree(chineseDistricts, dbRows, currentId);

                    /**
                     * 根据输入省份名称匹配标准省份键名
                     * @param {string} inputProv 输入的省份名
                     * @return {string}
                     */
                    var resolveProvinceKey = function (inputProv) {
                        var raw = String(inputProv || '').trim();
                        if (!raw) {
                            return '';
                        }
                        var norm = normalizeProvince(raw);
                        if (tree.cityMap[norm]) {
                            return norm;
                        }
                        for (var i = 0; i < tree.provinces.length; i++) {
                            if (tree.provinces[i].indexOf(raw) !== -1 || raw.indexOf(tree.provinces[i].replace(/省|市|自治区|特别行政区|壮族|回族|维吾尔/g, '')) !== -1) {
                                return tree.provinces[i];
                            }
                        }
                        return raw;
                    };

                    /**
                     * 关闭所有下拉面板
                     * @param {jQuery} [$exceptWrap] 排除不关闭的容器
                     */
                    var closeAllDropdowns = function ($exceptWrap) {
                        $('.fc-area-select-wrap').each(function () {
                            if (!$exceptWrap || !$(this).is($exceptWrap)) {
                                $(this).removeClass('is-open');
                            }
                        });
                    };

                    /**
                     * 滚动下拉框使当前选中项可见
                     * @param {jQuery} $dropdown 下拉面板元素
                     */
                    var scrollActiveIntoView = function ($dropdown) {
                        var $active = $dropdown.find('.fc-area-dropdown__item.is-active').first();
                        if ($active.length) {
                            var top = $active.position().top + $dropdown.scrollTop() - 40;
                            $dropdown.scrollTop(Math.max(0, top));
                        } else {
                            $dropdown.scrollTop(0);
                        }
                    };

                    /**
                     * 渲染省份下拉列表
                     * @param {boolean} filterByInput 是否根据当前输入内容过滤
                     */
                    var renderProvinceDropdown = function (filterByInput) {
                        var $dropdown = $('#province-dropdown');
                        var currentVal = String($province.val() || '').trim();
                        var currentNorm = normalizeProvince(currentVal);
                        var keyword = filterByInput ? currentVal.toLowerCase() : '';

                        var list = tree.provinces.filter(function (prov) {
                            if (!keyword) {
                                return true;
                            }
                            return prov.toLowerCase().indexOf(keyword) !== -1;
                        });

                        $dropdown.empty();
                        $('<div class="fc-area-dropdown__header">').text(
                            keyword ? ('搜索省份（匹配 ' + list.length + ' 项）') : ('全国省级行政区（共 ' + tree.provinces.length + ' 个，可输入搜索）')
                        ).appendTo($dropdown);

                        if (!list.length) {
                            $('<div class="fc-area-dropdown__empty">').text(
                                '未找到匹配省份，可直接保存自定义省份「' + currentVal + '」'
                            ).appendTo($dropdown);
                            return;
                        }

                        for (var i = 0; i < list.length; i++) {
                            var prov = list[i];
                            var cityCount = (tree.cityMap[prov] || []).length;
                            var $item = $('<div class="fc-area-dropdown__item">')
                                .toggleClass('is-active', prov === currentVal || prov === currentNorm)
                                .attr('data-province', prov);
                            $('<span class="fc-area-dropdown__main">').text(prov).appendTo($item);
                            if (cityCount > 0) {
                                $('<span class="fc-area-dropdown__sub">').text(cityCount + ' 个城市').appendTo($item);
                            }
                            $dropdown.append($item);
                        }
                        scrollActiveIntoView($dropdown);
                    };

                    /**
                     * 渲染城市下拉列表（支持按当前省份展示，或未选省份/跨省搜索时展示全国城市）
                     * @param {boolean} filterByInput 是否根据当前输入内容过滤
                     */
                    var renderCityDropdown = function (filterByInput) {
                        var $dropdown = $('#city-dropdown');
                        var provVal = resolveProvinceKey($province.val());
                        var currentCity = String($city.val() || '').trim();
                        var keyword = filterByInput ? currentCity.toLowerCase() : '';

                        $dropdown.empty();

                        var items = [];
                        var isNationalMode = false;

                        if (provVal && tree.cityMap[provVal] && !keyword) {
                            // 已选省份且未输入搜索词：展示该省下全部城市
                            var provCities = tree.cityMap[provVal] || [];
                            for (var i = 0; i < provCities.length; i++) {
                                items.push({
                                    province: provVal,
                                    city: provCities[i]
                                });
                            }
                        } else if (keyword) {
                            // 输入了关键字：优先当前省份匹配，若无匹配或未选省份则检索全国城市
                            if (provVal && tree.cityMap[provVal]) {
                                var pCities = tree.cityMap[provVal] || [];
                                for (var j = 0; j < pCities.length; j++) {
                                    if (pCities[j].toLowerCase().indexOf(keyword) !== -1) {
                                        items.push({
                                            province: provVal,
                                            city: pCities[j]
                                        });
                                    }
                                }
                            }
                            // 同时补充全国其他省份匹配的城市
                            isNationalMode = true;
                            for (var k = 0; k < tree.allCities.length; k++) {
                                var item = tree.allCities[k];
                                if (item.city.toLowerCase().indexOf(keyword) !== -1 || item.province.toLowerCase().indexOf(keyword) !== -1) {
                                    var exists = false;
                                    for (var m = 0; m < items.length; m++) {
                                        if (items[m].province === item.province && items[m].city === item.city) {
                                            exists = true;
                                            break;
                                        }
                                    }
                                    if (!exists) {
                                        items.push(item);
                                    }
                                }
                            }
                        } else {
                            // 未选省份：直接展示全国全部城市，点击自动带出所属省份
                            isNationalMode = true;
                            items = tree.allCities.slice(0);
                        }

                        var headerText = '';
                        if (keyword) {
                            headerText = '全国城市搜索结果（共 ' + items.length + ' 项，点击自动关联省份）';
                        } else if (!isNationalMode && provVal) {
                            headerText = provVal + ' · 下属城市（共 ' + items.length + ' 个，也可直接输入搜索全国城市）';
                        } else {
                            headerText = '全国全部城市（共 ' + items.length + ' 个，点击自动填充省份，可输入搜索）';
                        }
                        $('<div class="fc-area-dropdown__header">').text(headerText).appendTo($dropdown);

                        if (!items.length) {
                            $('<div class="fc-area-dropdown__empty">').text(
                                '未找到匹配城市，可直接保存自定义城市「' + currentCity + '」'
                            ).appendTo($dropdown);
                            return;
                        }

                        for (var idx = 0; idx < items.length; idx++) {
                            var cObj = items[idx];
                            var distCount = (tree.districtMap[cObj.province + '|' + cObj.city] || []).length;
                            var $item = $('<div class="fc-area-dropdown__item">')
                                .toggleClass('is-active', cObj.city === currentCity && (!provVal || cObj.province === provVal))
                                .attr('data-province', cObj.province)
                                .attr('data-city', cObj.city);
                            $('<span class="fc-area-dropdown__main">').text(cObj.city).appendTo($item);
                            var subText = isNationalMode ? cObj.province : (distCount ? (distCount + ' 个区县') : '');
                            if (subText) {
                                $('<span class="fc-area-dropdown__sub">').text(subText).appendTo($item);
                            }
                            $dropdown.append($item);
                        }
                        scrollActiveIntoView($dropdown);
                    };

                    /**
                     * 渲染区县下拉列表（支持按当前省市展示、已添加标记，以及全国区县关键字检索反填）
                     * @param {boolean} filterByInput 是否根据当前输入内容过滤
                     */
                    var renderDistrictDropdown = function (filterByInput) {
                        var $dropdown = $('#district-dropdown');
                        var provVal = resolveProvinceKey($province.val());
                        var cityVal = String($city.val() || '').trim();
                        var currentDist = String($district.val() || '').trim();
                        var keyword = filterByInput ? currentDist.toLowerCase() : '';

                        $dropdown.empty();

                        // 如果还没选省份但已选城市，尝试从全国城市反查省份
                        if (!provVal && cityVal) {
                            for (var cIdx = 0; cIdx < tree.allCities.length; cIdx++) {
                                if (tree.allCities[cIdx].city === cityVal) {
                                    provVal = tree.allCities[cIdx].province;
                                    break;
                                }
                            }
                        }

                        var items = [];
                        var isNationalSearch = false;
                        var key = provVal + '|' + cityVal;
                        var baseDistricts = tree.districtMap[key] || [];

                        if (baseDistricts.length > 0) {
                            for (var i = 0; i < baseDistricts.length; i++) {
                                var dName = baseDistricts[i];
                                if (!keyword || dName.toLowerCase().indexOf(keyword) !== -1) {
                                    items.push({
                                        province: provVal,
                                        city: cityVal,
                                        district: dName
                                    });
                                }
                            }
                        }

                        // 若在当前城市下未搜到或尚未选择省市，且有搜索词，则跨全国区县搜索
                        if (keyword && items.length === 0) {
                            isNationalSearch = true;
                            for (var j = 0; j < tree.allDistricts.length; j++) {
                                var dObj = tree.allDistricts[j];
                                if (dObj.district.toLowerCase().indexOf(keyword) !== -1) {
                                    items.push(dObj);
                                    if (items.length >= 120) {
                                        break;
                                    }
                                }
                            }
                        }

                        if (!provVal && !cityVal && !keyword) {
                            $('<div class="fc-area-dropdown__header">').text('区县选择提示').appendTo($dropdown);
                            $('<div class="fc-area-dropdown__empty">').text(
                                '请先选择省份或城市，也可直接在此输入区县名称搜索全国区县'
                            ).appendTo($dropdown);
                            return;
                        }

                        var headerText = isNationalSearch
                            ? ('全国区县搜索结果（点击自动填充省/市/区县）')
                            : ((cityVal || '当前城市') + ' · 下属区县（共 ' + items.length + ' 个，支持自定义输入）');
                        $('<div class="fc-area-dropdown__header">').text(headerText).appendTo($dropdown);

                        if (!items.length) {
                            $('<div class="fc-area-dropdown__empty">').text(
                                currentDist
                                    ? ('可直接保存自定义区县：「' + currentDist + '」')
                                    : '暂无预设区县，请直接输入区县名称'
                            ).appendTo($dropdown);
                            return;
                        }

                        for (var k = 0; k < items.length; k++) {
                            var item = items[k];
                            var isAdded = !!tree.addedMap[item.province + '|' + item.city + '|' + item.district];
                            var $item = $('<div class="fc-area-dropdown__item">')
                                .toggleClass('is-active', item.district === currentDist && item.city === cityVal)
                                .attr('data-province', item.province)
                                .attr('data-city', item.city)
                                .attr('data-district', item.district);
                            $('<span class="fc-area-dropdown__main">').text(item.district).appendTo($item);

                            if (isNationalSearch) {
                                $('<span class="fc-area-dropdown__sub">').text(item.province + ' / ' + item.city).appendTo($item);
                            } else if (isAdded) {
                                $('<span class="fc-area-dropdown__tag">').text('已添加').appendTo($item);
                            }
                            $dropdown.append($item);
                        }
                        scrollActiveIntoView($dropdown);
                    };

                    /**
                     * 展开指定层级的下拉面板
                     * @param {string} level province | city | district
                     * @param {boolean} filterByInput 是否按输入关键字过滤
                     */
                    var openDropdown = function (level, filterByInput) {
                        var $wrap = $('.fc-area-select-wrap[data-level="' + level + '"]');
                        closeAllDropdowns($wrap);
                        $wrap.addClass('is-open');
                        if (level === 'province') {
                            renderProvinceDropdown(!!filterByInput);
                        } else if (level === 'city') {
                            renderCityDropdown(!!filterByInput);
                        } else if (level === 'district') {
                            renderDistrictDropdown(!!filterByInput);
                        }
                    };

                    // 聚焦或点击输入框时展开完整候选列表（不因已有值而隐藏其他选项）
                    $province.on('focus click', function () {
                        openDropdown('province', false);
                    });
                    $city.on('focus click', function () {
                        openDropdown('city', false);
                    });
                    $district.on('focus click', function () {
                        openDropdown('district', false);
                    });

                    // 输入文字时按关键字实时过滤
                    $province.on('input', function () {
                        refreshPreview();
                        openDropdown('province', true);
                    });
                    $city.on('input', function () {
                        refreshPreview();
                        openDropdown('city', true);
                    });
                    $district.on('input', function () {
                        refreshPreview();
                        openDropdown('district', true);
                        autoResolveCoordinates();
                    });

                    // 选择省份项
                    $('#province-dropdown').on('mousedown', '.fc-area-dropdown__item', function (e) {
                        e.preventDefault();
                        var selectedProv = String($(this).attr('data-province') || '');
                        var prevProv = normalizeProvince($province.val());
                        $province.val(selectedProv).trigger('change').trigger('validate');

                        if (selectedProv !== prevProv) {
                            $city.val('');
                            $district.val('');
                        }

                        var cities = tree.cityMap[selectedProv] || [];
                        if (cities.length === 1) {
                            // 直辖市（如北京市 -> 北京市）自动填充城市并直接展开区县
                            $city.val(cities[0]).trigger('change').trigger('validate');
                            refreshPreview();
                            $district.trigger('focus');
                            openDropdown('district', false);
                        } else {
                            refreshPreview();
                            $city.trigger('focus');
                            openDropdown('city', false);
                        }
                    });

                    // 选择城市项（支持跨省选城自动反填省份）
                    $('#city-dropdown').on('mousedown', '.fc-area-dropdown__item', function (e) {
                        e.preventDefault();
                        var selectedProv = String($(this).attr('data-province') || '');
                        var selectedCity = String($(this).attr('data-city') || '');
                        var prevCity = String($city.val() || '').trim();

                        if (selectedProv && String($province.val() || '').trim() !== selectedProv) {
                            $province.val(selectedProv).trigger('change').trigger('validate');
                        }
                        $city.val(selectedCity).trigger('change').trigger('validate');

                        if (selectedCity !== prevCity) {
                            $district.val('');
                        }
                        refreshPreview();
                        $district.trigger('focus');
                        openDropdown('district', false);
                    });

                    // 选择区县项（支持全国搜索区县自动反填省份和城市）
                    $('#district-dropdown').on('mousedown', '.fc-area-dropdown__item', function (e) {
                        e.preventDefault();
                        var selectedProv = String($(this).attr('data-province') || '');
                        var selectedCity = String($(this).attr('data-city') || '');
                        var selectedDist = String($(this).attr('data-district') || '');

                        if (selectedProv && String($province.val() || '').trim() !== selectedProv) {
                            $province.val(selectedProv).trigger('change').trigger('validate');
                        }
                        if (selectedCity && String($city.val() || '').trim() !== selectedCity) {
                            $city.val(selectedCity).trigger('change').trigger('validate');
                        }
                        $district.val(selectedDist).trigger('change').trigger('validate');

                        closeAllDropdowns();
                        refreshPreview();
                        autoResolveCoordinates();
                    });

                    // 清空按钮事件（清空当前及下级，并重新展开当前下拉）
                    $('.fc-area-select-clear').on('mousedown', function (e) {
                        e.preventDefault();
                        e.stopPropagation();
                        var $wrap = $(this).closest('.fc-area-select-wrap');
                        var level = $wrap.attr('data-level');
                        if (level === 'province') {
                            $province.val('');
                            $city.val('');
                            $district.val('');
                            refreshPreview();
                            $province.trigger('focus');
                            openDropdown('province', false);
                        } else if (level === 'city') {
                            $city.val('');
                            $district.val('');
                            refreshPreview();
                            $city.trigger('focus');
                            openDropdown('city', false);
                        } else if (level === 'district') {
                            $district.val('');
                            refreshPreview();
                            $district.trigger('focus');
                            openDropdown('district', false);
                        }
                    });

                    // 点击组件外部时关闭下拉列表
                    $(document).on('mousedown.fcAreaDropdown', function (e) {
                        if (!$(e.target).closest('.fc-area-select-wrap').length) {
                            closeAllDropdowns();
                        }
                    });

                    // 按 ESC 关闭下拉列表
                    $(document).on('keydown.fcAreaDropdown', function (e) {
                        if (e.keyCode === 27) {
                            closeAllDropdowns();
                        }
                    });

                    // 地图选点完成回调：不仅填充坐标，还可根据地图所选位置自动反填省 / 市 / 区县
                    $('.fc-area-map-btn').data('callback', function (res) {
                        if (!res) {
                            return;
                        }
                        var fullText = String(res.address || '') + ' ' + ($.isArray(res.rawParts) ? res.rawParts.join(' ') : '');
                        var matchedProv = resolveProvinceKey(res.province || '');
                        if (!matchedProv && fullText) {
                            for (var pIdx = 0; pIdx < tree.provinces.length; pIdx++) {
                                var pCandidate = tree.provinces[pIdx];
                                var pShort = pCandidate.replace(/省|市|自治区|特别行政区|壮族|回族|维吾尔/g, '');
                                if (fullText.indexOf(pCandidate) !== -1 || (pShort.length >= 2 && fullText.indexOf(pShort) !== -1)) {
                                    matchedProv = pCandidate;
                                    break;
                                }
                            }
                        }

                        var matchedCity = String(res.city || '').trim();
                        if (matchedProv && tree.cityMap[matchedProv]) {
                            var cCandidates = tree.cityMap[matchedProv];
                            if (cCandidates.length === 1) {
                                matchedCity = cCandidates[0];
                            } else if (!matchedCity || cCandidates.indexOf(matchedCity) === -1) {
                                for (var cIdx = 0; cIdx < cCandidates.length; cIdx++) {
                                    var cItem = cCandidates[cIdx];
                                    var cShort = cItem.replace(/市|自治州|地区|盟/g, '');
                                    if (fullText.indexOf(cItem) !== -1 || (cShort.length >= 2 && fullText.indexOf(cShort) !== -1)) {
                                        matchedCity = cItem;
                                        break;
                                    }
                                }
                            }
                        }

                        var matchedDist = String(res.district || '').trim();
                        if (matchedProv && matchedCity && tree.districtMap[matchedProv + '|' + matchedCity]) {
                            var dCandidates = tree.districtMap[matchedProv + '|' + matchedCity];
                            if (!matchedDist || dCandidates.indexOf(matchedDist) === -1) {
                                for (var dIdx = 0; dIdx < dCandidates.length; dIdx++) {
                                    if (fullText.indexOf(dCandidates[dIdx]) !== -1) {
                                        matchedDist = dCandidates[dIdx];
                                        break;
                                    }
                                }
                            }
                        }

                        if (matchedProv) {
                            $province.val(matchedProv).trigger('change').trigger('validate');
                        }
                        if (matchedCity) {
                            $city.val(matchedCity).trigger('change').trigger('validate');
                        }
                        if (matchedDist) {
                            $district.val(matchedDist).trigger('change').trigger('validate');
                        }
                        refreshPreview();
                    });
                });
            }
        }
    };
    return Controller;
});