anki-md-template/模板-支持数学公式/正面内容模版.html

<div class="md-content">
    {{正面}}
</div>


<script>
    // 日志级别： debug、warn、error
    var config_logLevel = "error";

    var scriptUrls = [
        "https://gcore.jsdelivr.net/npm/markdown-it@14.1.0/dist/markdown-it.min.js",
        "https://gcore.jsdelivr.net/gh/highlightjs/cdn-release@11.11.1/build/highlight.min.js",
        "https://gcore.jsdelivr.net/npm/markdown-it-texmath@1.0.0/texmath.min.js",
        "https://gcore.jsdelivr.net/npm/katex@0.16.22/dist/katex.min.js"
    ];

    initDivLog();
    initScriptResource(scriptUrls).then(() => {
        // Anki 原来的逻辑执行完成后再转换内容
        setTimeout(() => {
            renderMarkDownFn();
        }, 0);
    })

    /**
     * 转换卡片内容为 markdown 网页格式
     */
    function renderMarkDownFn() {
        try {
            // 隐藏卡片
            hideQAContent()

            // 转换内容
            initAnkiMarkDownIt();
            initCensorUtil();
            document.querySelectorAll('.md-content').forEach((div) => {
                div.innerHTML = renderMarkDown(div.innerHTML);
                div.className = "markdown-body";
            });

            // 显示卡片
            showQAContent()
        } catch (e) {
            DivLog.error("Error: " + e);
        }
    }

    /**
     * 绘制内容为 markdown 网页格式
     * @param {string} text
     * @returns {string}
     */
    function renderMarkDown(text) {
        DivLog.debug("======================================");
        DivLog.debug("Original content：", text);

        // <code></code> 包裹的内容不做处理
        let code_tag_matches
        [text, code_tag_matches] = CensorUtil.censorCodeTag(text);
        if (code_tag_matches.length > 0) {
            DivLog.debug("After hide html tag <code></code>：", text);
        }

        // <mjx-container></mjx-container> 包裹的内容不做处理
        let mjx_tag_matches
        [text, mjx_tag_matches] = CensorUtil.censorMJXTag(text);
        if (mjx_tag_matches.length > 0) {
            DivLog.debug("After hide html tag <mjx-container></mjx-container>：", text);
        }

        text = text.trim()
            .replace(/&(amp|lt|gt|nbsp);/g, (_, type) => {
                const entities = {amp: '&', lt: '<', gt: '>', nbsp: ' '};
                return entities[type] || '';
            })
            .replace(/<br>/g, '\n');
        DivLog.debug("After reverse some HTML tags：", text);

        // 转换成 markdown 网页格式
        text = AnkiMarkDownIt.render(text);
        DivLog.debug("After markdown-it conversion：", text);

        // 还原隐藏的内容
        text = CensorUtil.decensorMJXTag(text, mjx_tag_matches)
        text = CensorUtil.decensorCodeTag(text, code_tag_matches)

        return text;
    }


    // 初始化-日志工具
    function initDivLog() {
        // 日志工具
        if (typeof DivLog === 'undefined') {
            window.DivLog = {
                LOG_LEVEL: "info",
                levelMap: {'debug': 5, 'info': 4, 'warn': 3, 'error': 2, 'off': 1},

                debug(...messages) {
                    if (this.levelMap[this.LOG_LEVEL] >= 5) {
                        this._log("", ...messages);
                    }
                },
                info(...messages) {
                    if (this.levelMap[this.LOG_LEVEL] >= 4) {
                        this._log("", ...messages);
                    }
                },
                warn(...messages) {
                    if (this.levelMap[this.LOG_LEVEL] >= 3) {
                        this._log("orange", ...messages);
                    }
                },
                error(...messages) {
                    if (this.levelMap[this.LOG_LEVEL] >= 2) {
                        this._log("red", ...messages);
                    }
                },
                _log(fontColor, ...messages) {
                    const messageDiv = document.createElement("div");
                    messageDiv.style.color = fontColor;
                    messages.forEach(message => {
                        messageDiv.appendChild(document.createTextNode(message));
                        messageDiv.appendChild(document.createElement("br"));
                    });
                    messageDiv.appendChild(document.createElement("hr"));
                    this._getMsgContainer().appendChild(messageDiv)
                },
                _getMsgContainer() {
                    let msgContainer = document.getElementById("msgContainer");
                    if (!msgContainer) {
                        msgContainer = document.createElement("div");
                        msgContainer.id = "msgContainer";
                        msgContainer.style.textAlign = "left";
                        // 将日志信息放在最后
                        let qa = document.getElementById("qa");
                        if (qa) {
                            qa.appendChild(msgContainer);
                        }
                    }
                    return msgContainer
                },
                clearLogDiv() {
                    const msgContainer = document.getElementById("msgContainer");
                    if (msgContainer) {
                        msgContainer.remove();
                    }
                }
            };
        }
        // 更新日志级别
        if (DivLog.LOG_LEVEL !== config_logLevel) {
            DivLog.LOG_LEVEL = config_logLevel;
        }
        // 清空日志
        DivLog.clearLogDiv();
    }

    /**
     * 初始化-javascript 资源
     * @param scriptUrls 多个资源地址数组
     * @returns {Promise<Awaited<unknown>[]>|Promise<void>}
     */
    function initScriptResource(scriptUrls) {
        if (typeof markdownit !== 'undefined') {
            DivLog.info("markdown-it is loaded!")
            return Promise.resolve();
        }

        DivLog.info("markdown-it did not load, re-adding triggers loading!")
        return Promise.all(scriptUrls.map(url => {
            return new Promise((resolve, reject) => {
                const script = document.createElement("script");
                script.onload = resolve;
                script.onerror = () => reject(new Error(`Failed to load script from ${url}`));
                script.src = url;
                document.head.appendChild(script);
            });
        })).catch(error => {
            DivLog.error(error);
            throw error;
        });
    }

    // 初始化-markdown-it
    function initAnkiMarkDownIt() {
        if (typeof AnkiMarkDownIt !== 'undefined') {
            DivLog.debug("AnkiMarkDownIt is init!")
            return;
        }
        DivLog.info("AnkiMarkDownIt did not init!")
        window.AnkiMarkDownIt = markdownit({
            // 配置参考：https://markdown-it.docschina.org/api/MarkdownIt.html#markdownit-new
            html: true,
            linkify: true,
            typographer: false, // 为 true 时，将 (C)、(R)、(TM) 转化为 ©、®、™
            breaks: true,       // 为 true 时，将 \n 转化为 <br>
            highlight: function (str, lang) {
                if (lang && hljs.getLanguage(lang)) {
                    try {
                        return hljs.highlight(str, {language: lang}).value
                    } catch (__) {
                    }
                }
                return '';
            }
        }).use(window.texmath, {
            engine: katex,
            // 数学公式标识符，参考：https://www.npmjs.com/package/markdown-it-texmath
            // 'dollars'：$...$ or $$...$$
            // 'brackets'： \(...\) or \[...\]，这个标识符号是 Anki 默认的，
            //    但安卓端数学公式的解析是在页面加载完成后执行，这里的 Markdown 转换会破坏公式，还是需要将 'brackets' 配置上
            delimiters: ['dollars', 'brackets'],
            // katex 的配置选项，参考：https://katex.org/docs/options
            katexOptions: {
                output: 'html',
                throwOnError: false, // true-页面展示解析异常，false-解析异常的公式展示原字符并标记为红色
                strict: (errorCode, errorMsg, token) => {
                    DivLog.warn('Warn: ' + errorCode + ' ' + errorMsg + ' ' + token);
                    return "ignore";
                }
            }
        });
    }

    // 初始化-特殊片段隐藏工具
    function initCensorUtil() {
        if (typeof CensorUtil === 'undefined') {
            const ANKI_CODE_REGEXP = /<code[^>]*>([\s\S]*?)<\/code>/g;
            const ANKI_CODE_REPLACE = "ANKI_CODE_REPLACE";
            const ANKI_MJX_REGEXP = /<mjx-container[^>]*>([\s\S]*?)<\/mjx-container>/g;
            const ANKI_MJX_REPLACE = "ANKI_MJX_CONTAINER_REPLACE";
            window.CensorUtil = {
                censorCodeTag: function (note_text) {
                    return this._censor(note_text, ANKI_CODE_REGEXP, ANKI_CODE_REPLACE)
                },
                censorMJXTag: function (note_text) {
                    return this._censor(note_text, ANKI_MJX_REGEXP, ANKI_MJX_REPLACE)
                },
                decensorCodeTag: function (note_text, replacements) {
                    return this._decensor(note_text, ANKI_CODE_REPLACE, replacements)
                },
                decensorMJXTag: function (note_text, replacements) {
                    return this._decensor(note_text, ANKI_MJX_REPLACE, replacements)
                },
                _censor: function (note_text, regexp, mask) {
                    /*Take note_text and replace every match of regexp with mask, simultaneously adding it to a string array*/
                    let matches = []
                    for (let match of note_text.matchAll(regexp)) {
                        matches.push(match[0])
                    }
                    return [note_text.replace(regexp, mask), matches]
                },
                _decensor: function (note_text, mask, replacements) {
                    for (let replacement of replacements) {
                        note_text = note_text.replace(mask, replacement)
                    }
                    return note_text
                }
            }
        }
    }


    // 隐藏卡片内容
    function hideQAContent() {
        // 卡片的内容都是放在 id 为 qa 的 div 中
        let qaElement = document.getElementById("qa");
        if (qaElement) {
            qaElement.style.opacity = "0";
        }
    }

    // 显示卡片内容
    function showQAContent() {
        let answerHr = document.getElementById("answer");
        if (answerHr) {
            answerHr.style.opacity = "1";
        }
        let qaElement = document.getElementById("qa");
        if (qaElement) {
            qaElement.style.opacity = "1";
        }
    }
</script>