/**
 * MediaInfo / BDInfo 文本 → 技术规格概要(DETAIL-1,纯函数)。原文另存,这里只取展示需要的字段:
 * 概要(容器、时长、总码率、大小)、视频轨、音频轨、字幕轨。认不出的字段留 null,不猜。
 */

export interface MediaGeneral {
  fileName: string | null;
  container: string | null;
  duration: string | null;
  overallBitrate: string | null;
  size: string | null;
}

export interface MediaVideoTrack {
  codec: string | null;
  resolution: string | null;
  frameRate: string | null;
  bitrate: string | null;
  bitDepth: string | null;
  /** HDR10 / HDR10+ / Dolby Vision P5 / HLG … 空数组 = SDR 或未知 */
  hdr: string[];
}

export interface MediaAudioTrack {
  language: string | null;
  codec: string | null;
  channels: string | null;
  bitrate: string | null;
  title: string | null;
  isDefault: boolean | null;
}

export interface MediaTextTrack {
  language: string | null;
  format: string | null;
  title: string | null;
  isDefault: boolean | null;
  forced: boolean | null;
}

export interface MediaSummary {
  kind: "mediainfo" | "bdinfo";
  general: MediaGeneral;
  video: MediaVideoTrack[];
  audio: MediaAudioTrack[];
  subtitles: MediaTextTrack[];
}

const LANG: Record<string, string> = {
  chinese: "中文",
  mandarin: "国语",
  cantonese: "粤语",
  zh: "中文",
  chi: "中文",
  zho: "中文",
  "zh-cn": "简体中文",
  "zh-hans": "简体中文",
  "zh-tw": "繁体中文",
  "zh-hk": "繁体中文",
  "zh-hant": "繁体中文",
  english: "英语",
  en: "英语",
  eng: "英语",
  japanese: "日语",
  ja: "日语",
  jpn: "日语",
  korean: "韩语",
  ko: "韩语",
  kor: "韩语",
  french: "法语",
  fr: "法语",
  german: "德语",
  de: "德语",
  spanish: "西班牙语",
  es: "西班牙语",
  italian: "意大利语",
  russian: "俄语",
  thai: "泰语",
  portuguese: "葡萄牙语",
  hindi: "印地语",
};

function language(v: string | null | undefined): string | null {
  if (!v) return null;
  const t = v.trim();
  return LANG[t.toLowerCase()] ?? t;
}

function yesNo(v: string | undefined): boolean | null {
  if (!v) return null;
  if (/^(yes|是)$/i.test(v.trim())) return true;
  if (/^(no|否)$/i.test(v.trim())) return false;
  return null;
}

/** 「3 840 pixels」→ 3840 */
const num = (v: string | undefined): number | null => {
  const m = v ? /([\d\s]+)/.exec(v.replace(/(\d)\s+(?=\d)/g, "$1")) : null;
  return m ? Number.parseInt(m[1]!.replace(/\s/g, ""), 10) || null : null;
};

/** 码率:去掉数字里的千分位空格 「4 561 kb/s」→「4561 kb/s」 */
const rate = (v: string | undefined): string | null => (v ? v.replace(/(\d)\s+(?=\d)/g, "$1").trim() : null);

function frameRate(v: string | undefined): string | null {
  const m = v ? /([\d.]+)/.exec(v) : null;
  if (!m) return null;
  const n = Number.parseFloat(m[1]!);
  return Number.isFinite(n) ? `${Number.isInteger(n) ? n : Number(n.toFixed(3))} fps` : null;
}

/** 声道数 + 布局 → 2.0 / 5.1 / 7.1 */
function channels(count: string | undefined, layout: string | undefined): string | null {
  const n = num(count);
  if (!n) return null;
  const lfe = layout ? /\bLFE\b/.test(layout) : n === 6 || n === 8;
  return lfe ? `${n - 1}.1` : `${n}.0`;
}

function hdrOf(fields: Record<string, string>): string[] {
  const out: string[] = [];
  const f = `${fields["HDR format"] ?? ""} ${fields.HDR_Format ?? ""}`;
  const dv = /Dolby Vision[^,]*,[^,]*,\s*Profile\s*([\d.]+)/i.exec(f);
  if (dv) out.push(`Dolby Vision P${dv[1]}`);
  else if (/Dolby Vision/i.test(f)) out.push("Dolby Vision");
  if (/HDR10\+|SMPTE ST 2094/i.test(f)) out.push("HDR10+");
  if (
    /HDR10(?!\+)|SMPTE ST 2086/i.test(f) ||
    (!out.length && /PQ|SMPTE ST 2084/.test(fields["Transfer characteristics"] ?? ""))
  )
    out.push("HDR10");
  if (/HLG/i.test(`${f} ${fields["Transfer characteristics"] ?? ""}`)) out.push("HLG");
  return [...new Set(out)];
}

/** 音频编码短名:MLP FBA → TrueHD,E-AC-3 → DDP,DTS XLL → DTS-HD MA;商业名带 Atmos 的加上 Atmos */
function audioCodec(f: Record<string, string>): string | null {
  const fmt = f.Format?.trim();
  if (!fmt) return f["Commercial name"] ?? null;
  const commercial = f["Commercial name"] ?? "";
  let name = fmt;
  if (/^MLP FBA/i.test(fmt)) name = "TrueHD";
  else if (/^E-AC-3/i.test(fmt)) name = "DDP";
  else if (/^AC-3/i.test(fmt)) name = "AC-3";
  else if (/^DTS/i.test(fmt))
    name = /XLL X|DTS:X/i.test(`${fmt} ${commercial}`)
      ? "DTS:X"
      : /XLL|Master Audio/i.test(`${fmt} ${commercial}`)
        ? "DTS-HD MA"
        : "DTS";
  else if (/^AAC/i.test(fmt)) name = "AAC";
  else if (/^PCM/i.test(fmt)) name = "LPCM";
  if (/Atmos/i.test(`${fmt} ${commercial}`) && !/Atmos/i.test(name)) name += " Atmos";
  return name;
}

/** 中文版 MediaInfo 键 → 英文键 */
const ZH_KEYS: Record<string, string> = {
  完整名称: "Complete name",
  格式: "Format",
  文件大小: "File size",
  时长: "Duration",
  总体码率: "Overall bit rate",
  码率: "Bit rate",
  宽度: "Width",
  高度: "Height",
  帧率: "Frame rate",
  位深: "Bit depth",
  声道数: "Channel(s)",
  声道布局: "Channel layout",
  语言: "Language",
  标题: "Title",
  默认: "Default",
  强制: "Forced",
  商业名称: "Commercial name",
  "HDR 格式": "HDR format",
  传输特质: "Transfer characteristics",
};

type Section = { type: "general" | "video" | "audio" | "text" | "other"; fields: Record<string, string> };

const SECTION_HEAD =
  /^(General|Video|Audio|Text|Menu|Chapters|Image|Other|概览|常规|概要|视频|音频|文本|字幕|菜单|章节)(?:\s*#\s*\d+)?\s*$/i;

function sectionType(name: string): Section["type"] {
  const n = name.toLowerCase();
  if (/^(general|概览|常规|概要)/.test(n)) return "general";
  if (/^(video|视频)/.test(n)) return "video";
  if (/^(audio|音频)/.test(n)) return "audio";
  if (/^(text|文本|字幕)/.test(n)) return "text";
  return "other";
}

function parseSections(text: string): Section[] {
  const out: Section[] = [];
  let cur: Section | null = null;
  for (const raw of text.replace(/\r/g, "").split("\n")) {
    const line = raw.trim();
    if (!line) continue;
    const head = SECTION_HEAD.exec(line);
    if (head) {
      cur = { type: sectionType(head[1]!), fields: {} };
      out.push(cur);
      continue;
    }
    if (!cur) continue;
    const m = /^(.+?)\s*[:：]\s(.*)$/.exec(line) ?? /^(.+?)\s{2,}[:：]\s*(.*)$/.exec(line);
    if (!m) continue;
    const key = ZH_KEYS[m[1]!.trim()] ?? m[1]!.trim();
    if (!(key in cur.fields)) cur.fields[key] = m[2]!.trim();
  }
  return out;
}

function baseName(p: string | undefined): string | null {
  return p ? (p.split(/[\\/]/).pop() ?? p).trim() || null : null;
}

function parseMediaInfoText(text: string): MediaSummary | null {
  const sections = parseSections(text);
  const g = sections.find((s) => s.type === "general")?.fields;
  const videos = sections.filter((s) => s.type === "video");
  if (!g && !videos.length) return null;
  const general: MediaGeneral = {
    fileName: baseName(g?.["Complete name"] ?? g?.["Movie name"]),
    container: g?.Format ?? null,
    duration: g?.Duration ?? null,
    overallBitrate: rate(g?.["Overall bit rate"]),
    size: g?.["File size"] ?? null,
  };
  const video = videos.map(({ fields: f }): MediaVideoTrack => {
    const w = num(f.Width);
    const h = num(f.Height);
    return {
      codec: f.Format ?? null,
      resolution: w && h ? `${w}×${h}` : null,
      frameRate: frameRate(f["Frame rate"] ?? f["Original frame rate"]),
      bitrate: rate(f["Bit rate"] ?? f["Nominal bit rate"]),
      bitDepth: num(f["Bit depth"]) ? `${num(f["Bit depth"])} bit` : null,
      hdr: hdrOf(f),
    };
  });
  const audio = sections
    .filter((s) => s.type === "audio")
    .map(
      ({ fields: f }): MediaAudioTrack => ({
        language: language(f.Language),
        codec: audioCodec(f),
        channels: channels(f["Channel(s)"], f["Channel layout"] ?? f["Channel positions"]),
        bitrate: rate(f["Bit rate"]),
        title: f.Title ?? null,
        isDefault: yesNo(f.Default),
      }),
    );
  const subtitles = sections
    .filter((s) => s.type === "text")
    .map(
      ({ fields: f }): MediaTextTrack => ({
        language: language(f.Language),
        format: f.Format ?? null,
        title: f.Title ?? null,
        isDefault: yesNo(f.Default),
        forced: yesNo(f.Forced),
      }),
    );
  return { kind: "mediainfo", general, video, audio, subtitles };
}

// ---------------- BDInfo ----------------

function bdVideo(codec: string, desc: string, bitrate: string | null): MediaVideoTrack {
  const parts = desc.split(/\s+\/\s+/).map((s) => s.trim());
  const res = parts.find((p) => /^\d{3,4}[pi]$/i.test(p)) ?? null;
  const hdr: string[] = [];
  for (const p of parts) {
    if (/^Dolby Vision/i.test(p)) hdr.push(p.replace(/^Dolby Vision\s*/i, "Dolby Vision ").trim());
    else if (/^HDR10\+?$/i.test(p) || /^HLG$/i.test(p)) hdr.push(p.toUpperCase());
  }
  return {
    codec: codec.replace(/\s*Video$/i, "").trim() || null,
    resolution: res,
    frameRate: frameRate(parts.find((p) => /fps$/i.test(p))),
    bitrate: bitrate ?? parts.find((p) => /bps$/i.test(p)) ?? null,
    bitDepth: parts.find((p) => /^\d+ bits?$/i.test(p))?.replace(/bits?$/i, "bit") ?? null,
    hdr,
  };
}

function bdAudioCodec(codec: string): string | null {
  const c = codec.replace(/\s*Audio$/i, "").trim();
  if (!c) return null;
  if (/TrueHD\/Atmos/i.test(c)) return "TrueHD Atmos";
  if (/TrueHD/i.test(c)) return "TrueHD";
  if (/Digital Plus/i.test(c)) return /Atmos/i.test(c) ? "DDP Atmos" : "DDP";
  if (/^Dolby Digital$/i.test(c)) return "AC-3";
  if (/DTS:X/i.test(c)) return "DTS:X";
  if (/DTS-HD Master/i.test(c)) return "DTS-HD MA";
  return c;
}

function bdAudio(codec: string, lang: string | null, desc: string, bitrate: string | null): MediaAudioTrack {
  const parts = desc.split(/\s+\/\s+/).map((s) => s.trim());
  return {
    language: language(lang),
    codec: bdAudioCodec(codec),
    channels: parts.find((p) => /^\d\.\d(?:\s|$|-)/.test(p))?.slice(0, 3) ?? null,
    bitrate: bitrate ?? parts.find((p) => /kbps$/i.test(p)) ?? null,
    title: null,
    isDefault: null,
  };
}

/** 「61,812,345,678 bytes」→「57.57 GiB」;认不出原样返回 */
function bdSize(v: string | null): string | null {
  const m = v ? /^([\d,]+)\s*bytes$/i.exec(v.trim()) : null;
  if (!m) return v;
  const n = Number(m[1]!.replace(/,/g, ""));
  const units = ["B", "KiB", "MiB", "GiB", "TiB"];
  let x = n;
  let i = 0;
  while (x >= 1024 && i < units.length - 1) {
    x /= 1024;
    i++;
  }
  return `${i ? x.toFixed(2) : x} ${units[i]}`;
}

/** 「2:22:48.521」→「2 h 22 min」,与 MediaInfo 写法一致 */
function bdDuration(v: string | null): string | null {
  const m = v ? /^(\d+):(\d{2}):(\d{2})/.exec(v.trim()) : null;
  if (!m) return v;
  const h = Number(m[1]);
  const min = Number(m[2]);
  return h ? `${h} h ${min} min` : `${min} min ${Number(m[3])} s`;
}

function parseBdInfoText(text: string): MediaSummary | null {
  const lines = text.replace(/\r/g, "").split("\n");
  const kv = (label: RegExp) => {
    for (const l of lines) {
      const m = new RegExp(`^\\s*${label.source}\\s*:\\s*(.+)$`, "i").exec(l);
      if (m) return m[1]!.trim();
    }
    return null;
  };
  const general: MediaGeneral = {
    fileName: kv(/(?:Disc Title|Disc Label)/),
    container: "Blu-ray",
    duration: bdDuration(kv(/Length/)),
    overallBitrate: kv(/Total Bitrate/),
    size: bdSize(kv(/(?:Disc Size|Size)/)),
  };
  const video: MediaVideoTrack[] = [];
  const audio: MediaAudioTrack[] = [];
  const subtitles: MediaTextTrack[] = [];

  // 简版:「Video: codec / bitrate / 2160p / …」「Audio: lang / codec / 7.1 / …」「Subtitle: lang / bitrate」
  for (const l of lines) {
    const m = /^\s*(Video|Audio|Subtitle)\s*:\s*(.+)$/i.exec(l);
    if (!m) continue;
    const parts = m[2]!.split(/\s+\/\s+/).map((s) => s.trim());
    const kind = m[1]!.toLowerCase();
    if (kind === "video") video.push(bdVideo(parts[0] ?? "", parts.slice(1).join(" / "), parts[1] ?? null));
    else if (kind === "audio") audio.push(bdAudio(parts[1] ?? "", parts[0] ?? null, parts.slice(2).join(" / "), null));
    else subtitles.push({ language: language(parts[0]), format: "PGS", title: null, isDefault: null, forced: null });
  }

  // 完整报告:VIDEO: / AUDIO: / SUBTITLES: 下的表格,列之间两个以上空格
  if (!video.length && !audio.length) {
    let section: "video" | "audio" | "subs" | null = null;
    for (const l of lines) {
      const head =
        /^\s*(VIDEO|AUDIO|SUBTITLES|FILES|CHAPTERS|STREAM DIAGNOSTICS|PLAYLIST REPORT|DISC INFO)\s*:\s*$/.exec(l);
      if (head) {
        section =
          head[1] === "VIDEO" ? "video" : head[1] === "AUDIO" ? "audio" : head[1] === "SUBTITLES" ? "subs" : null;
        continue;
      }
      if (!section || !l.trim() || /^\s*(Codec|-----)/.test(l)) continue;
      const cols = l.trim().split(/\s{2,}/);
      if (section === "video") video.push(bdVideo(cols[0] ?? "", cols[2] ?? "", cols[1] ?? null));
      else if (section === "audio") audio.push(bdAudio(cols[0] ?? "", cols[1] ?? null, cols[3] ?? "", cols[2] ?? null));
      else
        subtitles.push({
          language: language(cols[1]),
          format: /Presentation Graphics/i.test(cols[0] ?? "") ? "PGS" : (cols[0] ?? null),
          title: null,
          isDefault: null,
          forced: null,
        });
    }
  }
  if (!video.length && !audio.length) return null;
  return { kind: "bdinfo", general, video, audio, subtitles };
}

const isBdInfo = (t: string) =>
  /(^|\n)\s*(DISC INFO:|Disc Title\s*:|Disc Label\s*:|BDInfo\s*:|PLAYLIST REPORT:)/i.test(t);

/** MediaInfo 或 BDInfo 原文 → 概要;两种都认不出返回 null(前端只显示原文) */
export function parseMediaSummary(text: string | null | undefined): MediaSummary | null {
  if (!text?.trim()) return null;
  if (isBdInfo(text)) return parseBdInfoText(text) ?? parseMediaInfoText(text);
  return parseMediaInfoText(text);
}