// ==UserScript==
// @name         学习通绕过解锁粘贴限制
// @namespace    https://scriptcat.org/zh-CN/script-show-page/4835
// @version      1.7.0
// @description  解锁学习通 代码编辑区、UE编辑器、讨论区 的粘贴限制，以及小部分改进
// @author       Muyue
// @match        *://*.chaoxing.com/*
// @match        *://mooc1-*.chaoxing.com/*
// @connect      sso.chaoxing.com
// @grant        unsafeWindow
// @run-at       document-start
// @tag          学习通
// @tag          绕过粘贴限制
// @tag          粘贴
// @license CC BY-NC-SA 4.0
// ==/UserScript==

(function () {
    'use strict';

    const TAG = '[Unified-Paste]';
    const log = (...a) => console.log(TAG, ...a);
    const w = typeof unsafeWindow !== 'undefined' ? unsafeWindow : window;
    const MARK = '只能录入不能粘贴';

    function showNotice(msg) {
        if (w.$ && w.$.toast) {
            w.$.toast({ type: 'notice', content: msg });
        } else {
            log(msg);
        }
    }

    function initDiscussionLogic() {
        const checkObj = setInterval(() => {
            if (w.obj) {
                if (w.obj.circle) {
                    w.obj.circle.prohibitReplyPasting = 0;
                    log('Discussion config bypassed (prohibitReplyPasting=0)');
                }
                w.obj.isManager = 1;
                clearInterval(checkObj);
            }
        }, 500);
        setTimeout(() => clearInterval(checkObj), 10000);
        w.addEventListener('paste', function (e) {
            const target = e.target;
            if (target.tagName === 'TEXTAREA' || target.contentEditable === 'true') {
                e.stopImmediatePropagation();
            }
        }, true);
    }

    function isBlocker(fn) {
        if (typeof fn !== 'function' || fn.__unlocked) return false;
        try {
            return Function.prototype.toString.call(fn).indexOf(MARK) !== -1;
        } catch (e) {
            return false;
        }
    }

    function passthrough() {
        return true;
    }
    passthrough.__unlocked = true;

    // 作业页 allowPaste=="1" 时 editor.addListener('beforepaste', editorPaste)
    // editorPaste 清空 html.html 并 toast。全局拦截，覆盖之后创建的每一个 UE 实例。
    function initUEditorLogic() {
        let current = passthrough;
        const apply = (fn) => {
            if (isBlocker(fn)) {
                current = passthrough;
                log('editorPaste blocked');
                return;
            }
            if (typeof fn === 'function') current = fn;
        };
        try {
            apply(w.editorPaste);
            Object.defineProperty(w, 'editorPaste', {
                configurable: true,
                enumerable: true,
                get() { return current; },
                set: apply
            });
        } catch (e) {
            if (isBlocker(w.editorPaste)) w.editorPaste = passthrough;
        }

        const wrapAddListener = (owner) => {
            if (!owner || typeof owner.addListener !== 'function' || owner.addListener.__pasteWrapped) return;
            const raw = owner.addListener;
            const wrapped = function (type, fn) {
                if (type === 'beforepaste' && isBlocker(fn)) {
                    log('dropped beforepaste', this && (this.key || this.uid));
                    return this;
                }
                return raw.apply(this, arguments);
            };
            wrapped.__pasteWrapped = true;
            owner.addListener = wrapped;
        };

        const stripEditor = (editor) => {
            if (!editor) return;
            wrapAddListener(editor);
            const lists = [];
            if (editor.__allListeners && Array.isArray(editor.__allListeners.beforepaste)) {
                lists.push(editor.__allListeners.beforepaste);
            }
            if (editor._listeners && Array.isArray(editor._listeners.beforepaste)) {
                lists.push(editor._listeners.beforepaste);
            }
            lists.forEach((list) => {
                for (let i = list.length - 1; i >= 0; i--) {
                    const fn = list[i];
                    if (!isBlocker(fn)) continue;
                    if (typeof editor.removeListener === 'function') {
                        try { editor.removeListener('beforepaste', fn); } catch (err) {}
                    }
                    if (list[i] === fn) list.splice(i, 1);
                    log('removed beforepaste', editor.key || editor.uid);
                }
            });
        };

        const sweep = () => {
            const UE = w.UE;
            if (!UE) return;
            wrapAddListener(UE.Editor && UE.Editor.prototype);
            const map = UE.instants;
            if (!map) return;
            Object.keys(map).forEach((key) => {
                try { stripEditor(map[key]); } catch (err) {}
            });
        };

        let ueRef = w.UE;
        try {
            Object.defineProperty(w, 'UE', {
                configurable: true,
                enumerable: true,
                get() { return ueRef; },
                set(value) {
                    ueRef = value;
                    sweep();
                }
            });
        } catch (e) {}

        sweep();
        const timer = setInterval(sweep, 400);
        setTimeout(() => clearInterval(timer), 180000);

        // 页面 "1"==1 时写死 disablePasteImage / disableDraggable。
        // pasteimage 因此直接 return，粘贴文件不会上传再插入。
        const enablePasteFile = () => {
            const cfg = w.UEDITOR_CONFIG;
            if (cfg) {
                cfg.disablePasteImage = false;
                cfg.disableDraggable = false;
            }
            const UE = w.UE;
            const map = UE && UE.instants;
            if (!map) return;
            Object.keys(map).forEach((key) => {
                const editor = map[key];
                if (!editor || !editor.options) return;
                editor.options.disablePasteImage = false;
                editor.options.disableDraggable = false;
            });
        };
        enablePasteFile();
        const fileTimer = setInterval(enablePasteFile, 400);
        setTimeout(() => clearInterval(fileTimer), 180000);

        // 粘贴 doc/pdf 等非图片：按附件对话框同一条上传链，插入 insertCloud 卡片。
        const hookedBodies = new WeakSet();
        const val = (id) => {
            const el = w.document.getElementById(id);
            return el && el.value ? el.value : '';
        };
        const fileSizeText = (n) => {
            n = Number(n) || 0;
            if (n < 1024) return n + 'B';
            if (n < 1024 * 1024) return (n / 1024).toFixed(2) + 'K';
            return (n / 1024 / 1024).toFixed(2) + 'M';
        };
        const attachHtml = (rep) => {
            const dataType = String(rep.fileType || '').replace('.', '').toLowerCase();
            const url = String(rep.url || '');
            const mark = 'objectId=';
            const at = url.indexOf(mark);
            const objId = rep.objectid || (at >= 0 ? url.slice(at + mark.length) : '');
            if (!objId) return '';
            const fileName = rep.original || 'file';
            const size = fileSizeText(rep.size);
            const data = btoa(encodeURIComponent(JSON.stringify({
                objectid: objId,
                name: fileName,
                type: dataType,
                size: size
            })));
            return '<div class="editor-iframe" contenteditable="false"><iframe frameborder="0" scrolling="no" src="/ananas/common-modules/attachment/insertCloud.html" class="attach-iframe" module="insertAttach" objectid="' + objId + '" filename="' + fileName + '" filetype="' + dataType + '" filesize="' + size + '" name="' + data + '" style="display: block; max-width: 620px; width: 100%; height: 74px;"></iframe></div>';
        };
        const uploadPastedFile = (editor, file) => {
            const base = editor.getOpt && editor.getOpt('fileUrl');
            const enc = val('uploadEnc') || w.uploadEnc;
            const stamp = val('uploadTimeStamp') || w.currentTime;
            const uid = val('userId') || w.uid;
            if (!base || !enc || !stamp || !uid) {
                log('attachment upload skipped, missing auth');
                return;
            }
            const joiner = base.indexOf('?') >= 0 ? '&' : '?';
            const url = base + joiner + 'source=1&enc2=' + enc + '&t=' + stamp + '&uid=' + uid;
            const fd = new FormData();
            fd.append('upfile', file, file.name || 'paste.bin');
            fetch(url, { method: 'POST', body: fd, credentials: 'include' })
                .then((r) => r.json())
                .then((rep) => {
                    if (!rep || rep.state !== 'SUCCESS') {
                        log('attachment upload failed', rep && (rep.state || rep.status));
                        return;
                    }
                    const html = attachHtml(rep);
                    if (!html) return;
                    editor.focus();
                    editor.execCommand('insertHTML', html, true);
                    showNotice('已粘贴附件 ' + (rep.original || file.name));
                })
                .catch((err) => log('attachment upload error', err));
        };
        const hookDocPaste = () => {
            const UE = w.UE;
            const map = UE && UE.instants;
            if (!map) return;
            Object.keys(map).forEach((key) => {
                const editor = map[key];
                const body = editor && editor.body;
                if (!body || hookedBodies.has(body)) return;
                body.addEventListener('paste', function (e) {
                    const cd = e.clipboardData;
                    if (!cd || !cd.items) return;
                    const files = [];
                    for (let i = 0; i < cd.items.length; i++) {
                        const item = cd.items[i];
                        if (item.kind !== 'file') continue;
                        if (item.type && item.type.indexOf('image/') === 0) continue;
                        const file = item.getAsFile && item.getAsFile();
                        if (file) files.push(file);
                    }
                    if (!files.length) return;
                    e.preventDefault();
                    e.stopPropagation();
                    files.forEach((file) => uploadPastedFile(editor, file));
                });
                hookedBodies.add(body);
                log('doc paste upload hooked', editor.key || editor.uid);
            });
        };
        hookDocPaste();
        const docTimer = setInterval(hookDocPaste, 400);
        setTimeout(() => clearInterval(docTimer), 180000);
    }

    function initCodeEditorLogic() {
        const checkCodeEditor = setInterval(() => {
            var codeEditors = w.codeEditors || {};
            if (Object.keys(codeEditors).length === 0) return;

            clearInterval(checkCodeEditor);
            log('CodeMirror detected, unlocking paste...');

            for (let editorId in codeEditors) {
                let editor = codeEditors[editorId];
                if (editor && !editor._isUnlocked) {
                    editor.on('beforeChange', function (cm, change) {
                        if (change.origin === 'paste') {
                            change.cancel();
                            const pastedText = (event.clipboardData || w.clipboardData).getData('text');
                            const cursor = cm.getCursor();
                            cm.operation(function () {
                                cm.replaceRange(pastedText, cursor);
                            });
                            showNotice('已绕过代码粘贴限制 By.Muyue -imuyue.com');
                        }
                    });
                    editor._isUnlocked = true;
                }
            }
        }, 1000);
    }

    initDiscussionLogic();
    initUEditorLogic();
    w.addEventListener('load', () => {
        initCodeEditorLogic();
    });
})();