(function (global) {
    'use strict';

    /**
     * 壳侧桥：与游戏 iframe 内 Agent 通信（postMessage；同域可走 contentWindow 快路径探测）。
     * @constructor
     */
    function WorkbenchBridge() {
        this.iframe = null;
        this.ready = false;
        this.hibernating = false;
        this._reqId = 1;
        this._pending = {};
        this._listeners = {};
        this._targetOrigin = '*';
        this._boundMessage = this._onMessage.bind(this);
        this._crossOrigin = false;
        this._fallbackTried = false;
    }

    /**
     * @param {HTMLIFrameElement} iframe
     * @param {{crossOrigin?:boolean}} opts
     */
    WorkbenchBridge.prototype.attach = function (iframe, opts) {
        this.iframe = iframe;
        this._crossOrigin = !!(opts && opts.crossOrigin);
        window.addEventListener('message', this._boundMessage);
        var self = this;
        iframe.addEventListener('load', function () {
            self.call('ping').then(function () {
                self.ready = true;
            }).catch(function () { /* wait agent.ready event */ });
        });
    };

    WorkbenchBridge.prototype.detach = function () {
        window.removeEventListener('message', this._boundMessage);
        this.iframe = null;
        this.ready = false;
    };

    /**
     * @param {string} name
     * @param {function(*):void} cb
     */
    WorkbenchBridge.prototype.on = function (name, cb) {
        if (!this._listeners[name]) this._listeners[name] = [];
        this._listeners[name].push(cb);
    };

    WorkbenchBridge.prototype.off = function (name, cb) {
        var list = this._listeners[name];
        if (!list) return;
        var i = list.indexOf(cb);
        if (i >= 0) list.splice(i, 1);
    };

    WorkbenchBridge.prototype._emit = function (name, data) {
        var list = this._listeners[name] || [];
        for (var i = 0; i < list.length; i++) {
            try { list[i](data); } catch (e) { console.warn('[Bridge] listener', name, e); }
        }
    };

    WorkbenchBridge.prototype._onMessage = function (ev) {
        var msg = ev.data;
        if (!msg || msg.source !== 'pw-agent') return;
        if (msg.type === 'rpc-result' && msg.id != null && this._pending[msg.id]) {
            var p = this._pending[msg.id];
            delete this._pending[msg.id];
            if (msg.ok) p.resolve(msg.result);
            else p.reject(new Error(msg.error || 'rpc failed'));
            return;
        }
        if (msg.type === 'event') {
            if (msg.name === 'agent.ready') {
                this.ready = !!(msg.data && msg.data.ok);
            }
            if (msg.name === 'agent.hibernate') {
                this.hibernating = !!(msg.data && msg.data.on);
            }
            this._emit(msg.name, msg.data);
        }
    };

    /**
     * @param {string} method
     * @param {object=} params
     * @returns {Promise<*>}
     */
    WorkbenchBridge.prototype.call = function (method, params) {
        var self = this;
        return new Promise(function (resolve, reject) {
            if (!self.iframe || !self.iframe.contentWindow) {
                reject(new Error('iframe missing'));
                return;
            }
            // 同域快路径
            if (!self._crossOrigin) {
                try {
                    var agent = self.iframe.contentWindow.__PW_Agent;
                    if (agent && typeof agent._dispatch === 'function') {
                        var direct = agent._dispatch(method, params || {});
                        resolve(direct);
                        return;
                    }
                } catch (e) { /* fall through postMessage */ }
            }
            var id = self._reqId++;
            self._pending[id] = { resolve: resolve, reject: reject };
            var target = self._crossOrigin ? self._targetOrigin : '*';
            try {
                if (self.iframe.src) {
                    var u = new URL(self.iframe.src, location.href);
                    target = u.origin;
                    self._targetOrigin = target;
                }
            } catch (e2) { /* */ }
            self.iframe.contentWindow.postMessage({
                source: 'pw-bridge',
                id: id,
                method: method,
                params: params || {},
            }, target);
            setTimeout(function () {
                if (self._pending[id]) {
                    delete self._pending[id];
                    reject(new Error('rpc timeout: ' + method));
                }
            }, 8000);
        });
    };

    WorkbenchBridge.prototype.subscribe = function (channel) {
        return this.call('subscribe', { channel: channel });
    };

    WorkbenchBridge.prototype.unsubscribe = function (channel) {
        return this.call('unsubscribe', { channel: channel });
    };

    WorkbenchBridge.prototype.hibernate = function () {
        return this.call('hibernate');
    };

    WorkbenchBridge.prototype.wake = function () {
        return this.call('wake');
    };

    /**
     * 构建游戏页 URL；优先 localhost↔127.0.0.1 跨域，失败标记后同域降级。
     * @param {boolean=} forceSameOrigin
     * @returns {{url:string, crossOrigin:boolean}}
     */
    WorkbenchBridge.buildGameUrl = function (forceSameOrigin) {
        var u = new URL(location.href);
        u.searchParams.set('pw', 'game');
        var crossFail = false;
        try { crossFail = sessionStorage.getItem('pw-cross-fail') === '1'; } catch (e) { /* */ }
        var crossOrigin = false;
        if (!forceSameOrigin && !crossFail) {
            var host = location.hostname;
            if (host === 'localhost') {
                u.hostname = '127.0.0.1';
                crossOrigin = true;
            } else if (host === '127.0.0.1') {
                u.hostname = 'localhost';
                crossOrigin = true;
            }
        }
        return { url: u.toString(), crossOrigin: crossOrigin };
    };

    WorkbenchBridge.markCrossOriginFailed = function () {
        try { sessionStorage.setItem('pw-cross-fail', '1'); } catch (e) { /* */ }
    };

    global.PWBridge = WorkbenchBridge;
})(window);