// ==UserScript==
// @name         网络请求记录器
// @namespace    request-logger
// @version      1.0
// @description  拦截并记录网页中的 fetch / XHR 请求，支持导出为 JSON 文件
// @author       You
// @match        *://*/*
// @grant        GM_registerMenuCommand
// @run-at       document-start
// ==/UserScript==

(function() {
    'use strict';

    // 存储所有请求记录
    const requests = [];

    // 将拦截逻辑注入页面真实上下文（才能抓到页面自身的请求）
    function injectInterceptor() {
        const script = document.createElement('script');
        script.textContent = '(' + function() {
            // 拦截 fetch
            const origFetch = window.fetch;
            window.fetch = async function(input, init) {
                const url = input instanceof Request ? input.url : input;
                const options = input instanceof Request ? input : (init || {});
                
                const record = {
                    type: 'fetch',
                    url: String(url),
                    method: (options.method || 'GET').toUpperCase(),
                    headers: {},
                    body: null,
                    timestamp: new Date().toISOString()
                };

                if (options.headers) {
                    if (options.headers instanceof Headers) {
                        options.headers.forEach((v, k) => record.headers[k] = v);
                    } else {
                        record.headers = { ...options.headers };
                    }
                }
                if (options.body && typeof options.body === 'string') {
                    record.body = options.body;
                } else if (options.body) {
                    record.body = '[Binary/Object Body]';
                }

                window.postMessage({ source: 'REQUEST_LOGGER', data: record }, '*');
                return origFetch.apply(this, arguments);
            };

            // 拦截 XMLHttpRequest
            const origOpen = XMLHttpRequest.prototype.open;
            const origSend = XMLHttpRequest.prototype.send;
            const origSetHeader = XMLHttpRequest.prototype.setRequestHeader;

            XMLHttpRequest.prototype.open = function(method, url) {
                this._reqLog = {
                    type: 'xhr',
                    method: method.toUpperCase(),
                    url: String(url),
                    headers: {},
                    body: null,
                    timestamp: new Date().toISOString()
                };
                return origOpen.apply(this, arguments);
            };

            XMLHttpRequest.prototype.setRequestHeader = function(header, value) {
                if (this._reqLog) this._reqLog.headers[header] = value;
                return origSetHeader.apply(this, arguments);
            };

            XMLHttpRequest.prototype.send = function(body) {
                if (this._reqLog) {
                    if (body && typeof body === 'string') this._reqLog.body = body;
                    else if (body) this._reqLog.body = '[Binary/Object Body]';
                    window.postMessage({ source: 'REQUEST_LOGGER', data: this._reqLog }, '*');
                }
                return origSend.apply(this, arguments);
            };
        }.toString() + ')();';
        
        document.documentElement.appendChild(script);
        script.remove();
    }

    // 接收页面传来的请求数据
    window.addEventListener('message', (e) => {
        if (e.data && e.data.source === 'REQUEST_LOGGER') {
            requests.push(e.data.data);
        }
    });

    // 导出为 JSON 文件
    function exportJson() {
        if (requests.length === 0) {
            alert('暂无记录的请求，请先操作页面触发网络请求');
            return;
        }

        const payload = {
            exportTime: new Date().toISOString(),
            pageUrl: location.href,
            userAgent: navigator.userAgent,
            total: requests.length,
            requests: requests
        };

        const blob = new Blob([JSON.stringify(payload, null, 2)], { type: 'application/json' });
        const url = URL.createObjectURL(blob);

        const a = document.createElement('a');
        a.href = url;
        a.download = `requests_${location.hostname}_${Date.now()}.json`;
        document.body.appendChild(a);
        a.click();
        a.remove();

        URL.revokeObjectURL(url);
        console.log(`[请求记录器] 已导出 ${requests.length} 条请求`);
    }

    // 查看统计
    function showStats() {
        const typeCount = {};
        requests.forEach(r => { typeCount[r.type] = (typeCount[r.type] || 0) + 1; });
        alert(`📊 当前已记录 ${requests.length} 条请求\n` +
              Object.entries(typeCount).map(([k, v]) => `  · ${k.toUpperCase()}: ${v} 条`).join('\n'));
    }

    // 清空记录
    function clearLogs() {
        requests.length = 0;
        console.log('[请求记录器] 记录已清空');
    }

    // 注册 ScriptCat / 油猴 右键菜单命令
    if (typeof GM_registerMenuCommand !== 'undefined') {
        GM_registerMenuCommand('📥 导出请求记录 (JSON)', exportJson);
        GM_registerMenuCommand('📊 查看记录统计', showStats);
        GM_registerMenuCommand('🗑️ 清空记录', clearLogs);
    }

    // 同时暴露到控制台，方便手动调用
    window.exportRequests = exportJson;
    window.getRequestLogs = () => requests;

    // 页面开始时注入拦截器
    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', injectInterceptor);
    } else {
        injectInterceptor();
    }

    console.log('[请求记录器] 已启动，菜单或控制台(window.exportRequests)可导出JSON');
})();