// ==UserScript==
// @name         sb6657 & douyuEx 弹幕一键装填工具
// @namespace    http://tampermonkey.net/
// @version      26.6.1
// @description  从 sb6657 弹幕库筛选内容并填入 douyuEx 的弹幕发送小助手 !! 你必须已经安装 斗鱼ex (https://douyuex.com)
// @author       kbd
// @match        *://*.douyu.com/*
// @run-at       document-idle
// @grant        GM_xmlhttpRequest
// @connect      sb6657-database.pages.dev
// @license      MIT
// @noframes
// ==/UserScript==

(function () {
  "use strict";

  const DATABASE_URL = "https://sb6657-database.pages.dev/memes.jsonl";
  const ROOT_ID = "douyuex-meme-library-filter";
  const TEXTAREA_ID = "bloop__textarea";
  const START_SEND_ID = "bloop__checkbox_startSend";

  let memeLibrary = null;
  let libraryRequest = null;

  function createElement(tagName, options) {
    const element = document.createElement(tagName);
    const settings = options || {};

    if (settings.className) element.className = settings.className;
    if (settings.text !== undefined) element.textContent = settings.text;
    if (settings.type) element.type = settings.type;
    if (settings.placeholder) element.placeholder = settings.placeholder;
    if (settings.value !== undefined) element.value = settings.value;
    if (settings.title) element.title = settings.title;

    if (settings.attributes) {
      Object.keys(settings.attributes).forEach((name) => {
        element.setAttribute(name, settings.attributes[name]);
      });
    }

    if (settings.style) {
      Object.assign(element.style, settings.style);
    }

    return element;
  }

  function setStatus(statusElement, message, tone) {
    const colors = {
      info: "#6b7280",
      success: "#15803d",
      warning: "#b45309",
      error: "#dc2626",
    };

    statusElement.textContent = message;
    statusElement.style.color = colors[tone] || colors.info;
  }

  function setBusy(applyButton, refreshButton, isBusy) {
    applyButton.disabled = isBusy;
    refreshButton.disabled = isBusy;
    applyButton.style.opacity = isBusy ? "0.65" : "1";
    refreshButton.style.opacity = isBusy ? "0.65" : "1";
  }

  function requestJsonl() {
    return new Promise((resolve, reject) => {
      GM_xmlhttpRequest({
        method: "GET",
        url: DATABASE_URL,
        responseType: "text",
        timeout: 30000,
        onload(response) {
          if (response.status < 200 || response.status >= 300) {
            reject(new Error(`下载失败（HTTP ${response.status}）`));
            return;
          }

          resolve(response.responseText || "");
        },
        onerror() {
          reject(new Error("下载失败，请检查网络后重试。"));
        },
        ontimeout() {
          reject(new Error("下载超时，请稍后重试。"));
        },
      });
    });
  }

  function parseMemeLibrary(rawText) {
    const records = [];
    let skippedLines = 0;

    rawText.split(/\r?\n/).forEach((line) => {
      if (!line.trim()) return;

      try {
        const row = JSON.parse(line);
        const contentLength = row.content_length;
        const content = typeof row.content === "string"
          ? row.content.replace(/[\r\n]+/g, " ").trim()
          : "";
        const submittedAt = typeof row.submitted_at === "string"
          ? Date.parse(row.submitted_at)
          : Number.NaN;

        if (!content || typeof contentLength !== "number" || !Number.isSafeInteger(contentLength) || contentLength < 0) {
          skippedLines += 1;
          return;
        }

        records.push({
          content,
          contentLength,
          submittedAt: Number.isNaN(submittedAt) ? null : submittedAt,
        });
      } catch (error) {
        skippedLines += 1;
      }
    });

    if (!records.length) {
      throw new Error("弹幕库中没有可用的弹幕。");
    }

    return { records, skippedLines };
  }

  async function loadLibrary(forceRefresh, statusElement) {
    if (!forceRefresh && memeLibrary) return memeLibrary;
    if (libraryRequest) return libraryRequest;

    setStatus(statusElement, forceRefresh ? "正在刷新弹幕库…" : "正在下载弹幕库…", "info");

    libraryRequest = requestJsonl()
      .then(parseMemeLibrary)
      .then((parsed) => {
        memeLibrary = parsed.records;
        const suffix = parsed.skippedLines ? `，跳过 ${parsed.skippedLines} 条无效记录` : "";
        setStatus(statusElement, `弹幕库已加载：${memeLibrary.length} 条${suffix}。`, "success");
        return memeLibrary;
      })
      .catch((error) => {
        setStatus(statusElement, error.message || "弹幕库加载失败。", "error");
        throw error;
      })
      .finally(() => {
        libraryRequest = null;
      });

    return libraryRequest;
  }

  function readLimit(input, label) {
    const value = input.value.trim();
    if (!value) return { value: null };

    if (!/^\d+$/.test(value) || !Number.isSafeInteger(Number(value))) {
      return { error: `${label}必须是非负整数。` };
    }

    return { value: Number(value) };
  }

  function splitKeywords(value) {
    return [...new Set(value
      .split(",")
      .map((keyword) => keyword.trim().toLowerCase())
      .filter(Boolean))];
  }

  function readFilters(keywordInput, excludeKeywordInput, minLengthInput, maxLengthInput, afterTimeInput) {
    const minLength = readLimit(minLengthInput, "最小长度");
    const maxLength = readLimit(maxLengthInput, "最大长度");
    const afterTimeValue = afterTimeInput.value.trim();

    if (minLength.error) return { error: minLength.error };
    if (maxLength.error) return { error: maxLength.error };
    if (minLength.value !== null && maxLength.value !== null && minLength.value > maxLength.value) {
      return { error: "最小长度不能大于最大长度。" };
    }
    const afterTime = afterTimeValue ? Date.parse(afterTimeValue) : null;
    if (afterTimeValue && Number.isNaN(afterTime)) {
      return { error: "筛选时间无效。" };
    }

    return {
      keywords: splitKeywords(keywordInput.value),
      excludeKeywords: splitKeywords(excludeKeywordInput.value),
      minLength: minLength.value === null ? 0 : minLength.value,
      maxLength: maxLength.value === null ? Infinity : maxLength.value,
      afterTime,
    };
  }

  function filterMemes(records, filters) {
    return records.filter((record) => {
      const normalizedContent = record.content.toLowerCase();
      const hasKeyword = !filters.keywords.length || filters.keywords.some((keyword) => normalizedContent.includes(keyword));
      const avoidsExcludedKeyword = !filters.excludeKeywords.some((keyword) => normalizedContent.includes(keyword));
      const isAfterTime = filters.afterTime === null || (record.submittedAt !== null && record.submittedAt > filters.afterTime);
      return hasKeyword
        && avoidsExcludedKeyword
        && record.contentLength >= filters.minLength
        && record.contentLength <= filters.maxLength
        && isAfterTime;
    });
  }

  function stopActiveLoop() {
    const startCheckbox = document.getElementById(START_SEND_ID);
    if (!startCheckbox || !startCheckbox.checked) return false;

    startCheckbox.click();
    return true;
  }

  function isTiangouModeEnabled() {
    const tiangouCheckbox = document.getElementById("bloop__checkbox_tiangou");
    return Boolean(tiangouCheckbox && tiangouCheckbox.checked);
  }

  function applyResults(textarea, matches) {
    textarea.value = matches.map((record) => record.content).join("\n");
    textarea.dispatchEvent(new Event("input", { bubbles: true }));
  }

  function insertFilterPanel(textarea) {
    if (document.getElementById(ROOT_ID)) return true;

    const root = createElement("div", {
      attributes: { id: ROOT_ID },
      style: {
        position: "absolute",
        left: "0",
        right: "0",
        bottom: "100%",
        zIndex: "1",
        boxSizing: "border-box",
        maxHeight: "calc(100vh - 200px)",
        overflowY: "auto",
        backgroundColor: "rgba(255, 255, 255, 0.98)",
        borderBottom: "1px solid rgba(128, 128, 128, 0.35)",
        padding: "0 0 9px",
        fontSize: "13px",
        lineHeight: "1.5",
      },
    });

    const title = createElement("div", {
      text: "sb6657 弹幕库装填器🚀",
      style: { fontWeight: "600", marginBottom: "6px" },
    });
    const fields = createElement("div", {
      style: { display: "flex", flexWrap: "wrap", gap: "6px", alignItems: "center" },
    });
    const keywordInput = createElement("input", {
      type: "text",
      placeholder: "关键词（英文逗号分隔，可留空）",
      title: "按弹幕正文包含的关键词筛选",
      attributes: { "aria-label": "关键词" },
      style: { boxSizing: "border-box", flex: "1 1 145px", minWidth: "120px" },
    });
    const excludeKeywordInput = createElement("input", {
      type: "text",
      placeholder: "排除关键词（英文逗号分隔，可留空）",
      title: "排除正文包含任意一个关键词的弹幕",
      attributes: { "aria-label": "排除关键词" },
      style: { boxSizing: "border-box", flex: "1 1 145px", minWidth: "120px" },
    });
    const minLengthInput = createElement("input", {
      type: "number",
      placeholder: "最小长度",
      title: "留空表示不限",
      attributes: { min: "0", step: "1", inputmode: "numeric", "aria-label": "最小长度" },
      style: { boxSizing: "border-box", width: "82px" },
    });
    const maxLengthInput = createElement("input", {
      type: "number",
      placeholder: "最大长度",
      title: "留空表示不限",
      attributes: { min: "0", step: "1", inputmode: "numeric", "aria-label": "最大长度" },
      style: { boxSizing: "border-box", width: "82px" },
    });
    const afterTimeInput = createElement("input", {
      type: "datetime-local",
      title: "只保留晚于此时间点提交的弹幕，留空表示不限",
      attributes: { step: "1", "aria-label": "晚于此时间" },
      style: { boxSizing: "border-box", width: "190px" },
    });
    const applyButton = createElement("button", { type: "button", text: "筛选并替换" });
    const refreshButton = createElement("button", { type: "button", text: "刷新库" });
    const status = createElement("div", {
      text: "首次筛选时将下载弹幕库。",
      attributes: { "aria-live": "polite" },
      style: { marginTop: "6px", minHeight: "20px", color: "#6b7280" },
    });

    fields.append(keywordInput, excludeKeywordInput, minLengthInput, maxLengthInput, afterTimeInput, applyButton, refreshButton);
    root.append(title, fields, status);
    const assistantPanel = textarea.closest(".bloop") || textarea.parentElement;
    assistantPanel.insertBefore(root, assistantPanel.firstChild);
    if (assistantPanel.classList.contains("bloop")) {
      assistantPanel.style.height = "";
      assistantPanel.style.bottom = "";
    }

    applyButton.addEventListener("click", async () => {
      const filters = readFilters(keywordInput, excludeKeywordInput, minLengthInput, maxLengthInput, afterTimeInput);
      if (filters.error) {
        setStatus(status, filters.error, "error");
        return;
      }

      setBusy(applyButton, refreshButton, true);
      try {
        const records = await loadLibrary(false, status);
        const matches = filterMemes(records, filters);
        const stopped = stopActiveLoop();
        applyResults(textarea, matches);
        const stoppedText = stopped ? "已停止当前发送；" : "";
        const tiangouText = isTiangouModeEnabled() ? "请先关闭舔狗模式，再手动开始发送。" : "请手动开始发送。";
        setStatus(status, `${stoppedText}已替换输入框：${matches.length} 条弹幕。${tiangouText}`, matches.length ? "success" : "warning");
      } catch (error) {
        // loadLibrary 保留了文本区和显示下载错误
      } finally {
        setBusy(applyButton, refreshButton, false);
      }
    });

    refreshButton.addEventListener("click", async () => {
      setBusy(applyButton, refreshButton, true);
      try {
        await loadLibrary(true, status);
      } catch (error) {
        // loadLibrary 显示过下载错误了
      } finally {
        setBusy(applyButton, refreshButton, false);
      }
    });

    return true;
  }

  function mountWhenDouyuExIsReady() {
    const textarea = document.getElementById(TEXTAREA_ID);
    if (!textarea) return false;
    return insertFilterPanel(textarea);
  }

  if (mountWhenDouyuExIsReady()) return;

  const observer = new MutationObserver(() => {
    if (mountWhenDouyuExIsReady()) observer.disconnect();
  });

  observer.observe(document.documentElement, { childList: true, subtree: true });
  window.addEventListener("beforeunload", () => observer.disconnect(), { once: true });
})();