import { createHash } from "node:crypto";
import {
  mkdir,
  readFile,
  readdir,
  rename,
  stat,
  writeFile,
} from "node:fs/promises";
import path from "node:path";
import { fileURLToPath } from "node:url";
import { prepareContentObjects } from "./content-objects.mjs";
import contentPolicy from "../../shared/content-policy.json" with { type: "json" };

const SCRIPT_DIRECTORY = path.dirname(fileURLToPath(import.meta.url));
export const PROJECT_ROOT = path.resolve(SCRIPT_DIRECTORY, "../..");
const WOW_CAMPAIGN_CATALOG_PATH = path.join(
  PROJECT_ROOT,
  "src",
  "game",
  "generated",
  "dungeonCampaignCatalog.json",
);
export const CONTENT_SCHEMA_VERSION = 1;
export const DEFAULT_MINIMUM_APP_VERSION = "0.1.0";
export const WOW_CAMPAIGN_DUNGEON_COUNT = 54;
export const BUNDLED_ANDROID_PACKS = Object.freeze([...contentPolicy.bootstrapPackIds]);
export const RANDOMIZED_BITE_SIZED_PACK_DEFINITION = Object.freeze({
  id: "activity:randomized-bite-sized",
  label: "Randomized Bite-Sized Base",
  bundledOnAndroid: false,
  dependencies: ["dungeon:stormwind-stockade"],
});

const RUNTIME_EXTENSIONS = new Set([
  ".avif", ".glb", ".js", ".json", ".ktx2", ".mp3", ".ogg", ".png",
  ".svg", ".wasm", ".wav", ".webm", ".webp",
]);

export const BASIC_HUMAN_TEXTURE_PATHS = Object.freeze([
  "assets/characters/wow335a-v1/textures/character/human/faciallowerhair00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/facialupperhair00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/female/humanfemalefacelower00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/female/humanfemalefaceupper00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/female/humanfemalenakedpelvisskin00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/female/humanfemalenakedtorsoskin00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/female/humanfemaleskin00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/hair00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/male/humanmalefacelower00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/male/humanmalefaceupper00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/male/humanmalenakedpelvisskin00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/male/humanmaleskin00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/scalplowerhair00_00.webp",
  "assets/characters/wow335a-v1/textures/character/human/scalpupperhair00_00.webp",
]);
const BASIC_HUMAN_TEXTURE_PATH_SET = new Set(BASIC_HUMAN_TEXTURE_PATHS);

export const DEFAULT_CONTENT_SOURCES = Object.freeze([
  {
    directory: path.join(PROJECT_ROOT, "public", "assets"),
    logicalPrefix: "assets",
  },
  {
    directory: path.join(PROJECT_ROOT, "src", "assets", "game", "dungeons"),
    logicalPrefix: "assets/game/dungeons",
  },
]);

function normalizedRelativePath(value) {
  return value.split(path.sep).join("/").replace(/^\/+/, "");
}

function encodeUrlPath(value) {
  return value.split("/").map(encodeURIComponent).join("/");
}

function packLabel(packId) {
  const [category, id = category] = packId.split(":", 2);
  const name = id.split("-").map((part) => `${part.slice(0, 1).toUpperCase()}${part.slice(1)}`).join(" ");
  if (category === "dungeon") return name;
  if (category === "creatures") return `${name} Creatures`;
  if (packId === "characters:wow335a-v1") return "Extra Wrath Character Models & Skins";
  if (packId === "characters:ascension-v1") return "Ascension Character Models & Skins";
  if (packId === "characters:runewaker-v1") return "RuneWaker Character Models & Skins";
  if (category === "characters") return `${name} Character Models & Skins`;
  if (category === "manastorm") return `${name} Manastorm`;
  if (packId === "shared:creatures") return "Shared Creatures";
  if (packId === "core:ui") return "Interface";
  if (packId === "core:equipment") return "Starter Equipment";
  if (packId === "core:character-basic") return "Basic Human Character Model";
  if (packId === "core:runtime") return "Game Runtime";
  if (packId === "core:arenas") return "Rated Arenas";
  if (packId === "core:combat-media") return "Original Spell Effects & Sounds";
  return name;
}

export function contentPackForPath(logicalPath) {
  const normalizedPath = normalizedRelativePath(logicalPath);
  const segments = normalizedPath.split("/");
  if (segments[0] === "basis" || segments[0] === "data") return "core:runtime";
  if (segments[0] !== "assets") return "core:misc";
  if (segments[1] === "characters" && segments[2]) {
    const basicWrathHuman = segments[2] === "wow335a-v1" && (
      segments[3] === "manifest.json"
      || segments[3] === "human"
      || BASIC_HUMAN_TEXTURE_PATH_SET.has(normalizedPath)
    );
    return basicWrathHuman ? "core:character-basic" : `characters:${segments[2]}`;
  }
  if (segments[1] === "creatures" && segments[2]) {
    return segments[2] === "shared" ? "shared:creatures" : `creatures:${segments[2]}`;
  }
  if (segments[1] === "game" && segments[2] === "creatures" && segments[3]) {
    return segments[3] === "shared" ? "shared:creatures" : `creatures:${segments[3]}`;
  }
  if (segments[1] === "game" && segments[2] === "dungeons" && segments[3]) {
    if (segments[4] === "creatures") return `creatures:${segments[3]}`;
    return `dungeon:${segments[3]}`;
  }
  if (segments[1] === "game" && segments[2] === "arenas") return "core:arenas";
  if (segments[1] === "game" && segments[2] === "manastorm" && segments[3]) {
    return `manastorm:${segments[3]}`;
  }
  if (segments[1] === "game" && segments[2] === "combat-effects") return "core:combat-media";
  if (segments[1] === "ui") return "core:ui";
  if (segments[1] === "equipment") return "core:equipment";
  return "core:misc";
}

async function walkFiles(directory) {
  const rootStats = await stat(directory);
  if (rootStats.isFile()) {
    return RUNTIME_EXTENSIONS.has(path.extname(directory).toLowerCase()) ? [directory] : [];
  }
  const files = [];
  async function visit(current) {
    const entries = await readdir(current, { withFileTypes: true });
    entries.sort((left, right) => left.name.localeCompare(right.name));
    for (const entry of entries) {
      const fullPath = path.join(current, entry.name);
      if (entry.isDirectory()) await visit(fullPath);
      else if (entry.isFile() && RUNTIME_EXTENSIONS.has(path.extname(entry.name).toLowerCase())) files.push(fullPath);
    }
  }
  await visit(directory);
  return files;
}

async function sha256File(filePath) {
  const { createReadStream } = await import("node:fs");
  return new Promise((resolve, reject) => {
    const hash = createHash("sha256");
    const stream = createReadStream(filePath);
    stream.on("error", reject);
    stream.on("data", (chunk) => hash.update(chunk));
    stream.on("end", () => resolve(hash.digest("hex")));
  });
}

export async function scanContentSources(sources = DEFAULT_CONTENT_SOURCES) {
  const discovered = new Map();
  for (const source of sources) {
    const sourceDirectory = path.resolve(source.directory);
    const files = await walkFiles(sourceDirectory);
    for (const sourcePath of files) {
      const relative = normalizedRelativePath(path.relative(sourceDirectory, sourcePath));
      const logicalPath = normalizedRelativePath(relative
        ? `${source.logicalPrefix}/${relative}`
        : source.logicalPrefix);
      const fileStats = await stat(sourcePath);
      const sha256 = await sha256File(sourcePath);
      const prior = discovered.get(logicalPath);
      if (prior) {
        if (prior.sha256 !== sha256) {
          throw new Error(`Two content sources map different files to ${logicalPath}`);
        }
        continue;
      }
      discovered.set(logicalPath, {
        logicalPath,
        sourcePath,
        sha256,
        bytes: fileStats.size,
        extension: path.extname(sourcePath).toLowerCase(),
        packId: contentPackForPath(logicalPath),
      });
    }
  }
  return [...discovered.values()].sort((left, right) => left.logicalPath.localeCompare(right.logicalPath));
}

function contentVersion(files, packs) {
  const digest = createHash("sha256");
  for (const file of files) digest.update(`${file.logicalPath}\0${file.sha256}\0${file.bytes}\0${JSON.stringify(file.download ?? null)}\n`);
  for (const pack of packs) {
    digest.update(`pack\0${pack.id}\0${pack.label}\0${pack.bundledOnAndroid}\0${pack.dependencies.join(",")}\n`);
  }
  return `content-${digest.digest("hex").slice(0, 16)}`;
}

function assetPackId(url) {
  if (typeof url !== "string" || !url.startsWith("/")) return null;
  return contentPackForPath(url.slice(1));
}

/**
 * Builds the logical install topology for the 54-dungeon WoW campaign.
 * Environment and creature files remain independently downloadable. A dungeon
 * pack pulls in exactly the environment and creature packs referenced by its
 * generated definition, while randomized modes can install creatures alone.
 */
export function campaignDungeonPackDefinitions(definitions) {
  const packs = new Map();
  for (const definition of definitions) {
    const dungeonPackId = `dungeon:${definition.id}`;
    if (definition.id === "wailing-caverns") {
      const referencedCreaturePacks = new Set([
        "creatures:wailing-caverns",
        ...Object.values(definition.entities ?? {})
          .map((entity) => entity.visual?.model?.url)
          .filter(Boolean)
          .map(assetPackId),
      ]);
      const unexpectedCreaturePacks = [...referencedCreaturePacks]
        .filter((id) => id !== "creatures:wailing-caverns" && id !== "shared:creatures");
      if (unexpectedCreaturePacks.length) {
        throw new Error(`${definition.id} references unexpected creature packs: ${unexpectedCreaturePacks.join(", ")}`);
      }
      packs.set(dungeonPackId, {
        id: dungeonPackId,
        label: definition.title ?? packLabel(dungeonPackId),
        bundledOnAndroid: true,
        dependencies: [...referencedCreaturePacks],
      });
      continue;
    }
    const environmentUrls = [
      ...(definition.assets?.visual ?? []).map((asset) => asset.url),
      ...(definition.assets?.collision ?? []).map((asset) => asset.url),
      definition.assets?.navigation?.url,
    ].filter(Boolean);
    const resolvedEnvironmentPacks = environmentUrls.map(assetPackId);
    if (!resolvedEnvironmentPacks.length
      || resolvedEnvironmentPacks.some((id) => !id?.startsWith("manastorm:"))) {
      throw new Error(`${definition.id} has an environment asset outside its expected content pack.`);
    }
    const environmentPackIds = new Set(resolvedEnvironmentPacks);
    if (environmentPackIds.size !== 1) {
      throw new Error(`${definition.id} must resolve to exactly one Manastorm environment pack.`);
    }
    const [environmentPackId] = environmentPackIds;
    if (environmentPackId !== dungeonPackId) {
      packs.set(environmentPackId, {
        id: environmentPackId,
        label: packLabel(environmentPackId),
        bundledOnAndroid: false,
        dependencies: [],
      });
    }

    const creatureUrls = Object.values(definition.entities ?? {})
      .map((entity) => entity.visual?.model?.url)
      .filter(Boolean);
    const resolvedCreaturePacks = creatureUrls.map(assetPackId);
    if (resolvedCreaturePacks.some((id) => !id)) {
      throw new Error(`${definition.id} has a creature asset outside a content pack.`);
    }
    const referencedCreaturePacks = new Set(resolvedCreaturePacks);
    const expectedCreaturePackId = `creatures:${definition.id}`;
    const unexpectedCreaturePacks = [...referencedCreaturePacks]
      .filter((id) => id !== expectedCreaturePackId && id !== "shared:creatures");
    if (unexpectedCreaturePacks.length) {
      throw new Error(`${definition.id} references unexpected creature packs: ${unexpectedCreaturePacks.join(", ")}`);
    }
    packs.set(dungeonPackId, {
      id: dungeonPackId,
      label: definition.title ?? packLabel(dungeonPackId),
      bundledOnAndroid: definition.id === "wailing-caverns",
      dependencies: [
        ...(environmentPackId === dungeonPackId ? [] : [environmentPackId]),
        ...referencedCreaturePacks,
      ],
    });
  }
  return [...packs.values()].sort((left, right) => left.id.localeCompare(right.id));
}

export async function loadCampaignDungeonPackDefinitions(
  catalogPath = WOW_CAMPAIGN_CATALOG_PATH,
) {
  const definitions = await loadCampaignDungeonDefinitions(catalogPath);
  return campaignDungeonPackDefinitions(definitions);
}

export async function loadCampaignDungeonDefinitions(
  catalogPath = WOW_CAMPAIGN_CATALOG_PATH,
) {
  const campaign = JSON.parse(await readFile(catalogPath, "utf8"));
  if (!Array.isArray(campaign.definitions)) {
    throw new Error(`WoW campaign catalog is missing definitions: ${catalogPath}`);
  }
  if (campaign.definitions.length !== WOW_CAMPAIGN_DUNGEON_COUNT) {
    throw new Error(
      `WoW campaign catalog must contain ${WOW_CAMPAIGN_DUNGEON_COUNT} dungeons; found ${campaign.definitions.length}.`,
    );
  }
  const dungeonIds = campaign.definitions.map((definition) => definition?.id);
  if (dungeonIds.some((id) => typeof id !== "string" || !id)
    || new Set(dungeonIds).size !== dungeonIds.length) {
    throw new Error("WoW campaign catalog contains a missing or duplicate dungeon id.");
  }
  return campaign.definitions;
}

export function createContentManifest(files, options = {}) {
  const baseUrl = String(options.baseUrl ?? "/content/objects").replace(/\/+$/, "");
  const packs = new Map();
  const fileEntries = {};

  for (const file of files) {
    const objectName = `${file.sha256}${file.extension}`;
    const logicalUrl = `/${normalizedRelativePath(file.logicalPath)}`;
    fileEntries[logicalUrl] = {
      packId: file.packId,
      url: `${baseUrl}/${encodeUrlPath(objectName)}`,
      sha256: file.sha256,
      bytes: file.bytes,
      ...(file.download ? { download: file.download } : {}),
    };
    const pack = packs.get(file.packId) ?? {
      id: file.packId,
      label: packLabel(file.packId),
      bytes: 0,
      fileCount: 0,
      bundledOnAndroid: BUNDLED_ANDROID_PACKS.includes(file.packId),
      dependencies: [],
    };
    pack.bytes += file.bytes;
    pack.fileCount += 1;
    packs.set(file.packId, pack);
  }

  if (packs.has("shared:creatures")) {
    for (const pack of packs.values()) {
      if ((pack.id.startsWith("dungeon:") && pack.id !== "dungeon:wailing-caverns")
        || pack.id.startsWith("manastorm:")) {
        pack.dependencies = ["shared:creatures"];
      }
    }
  }
  if (packs.has("core:character-basic")) {
    for (const pack of packs.values()) {
      if (pack.id.startsWith("characters:")) pack.dependencies = ["core:character-basic"];
    }
  }

  for (const declared of options.packDefinitions ?? []) {
    const current = packs.get(declared.id) ?? {
      id: declared.id,
      label: packLabel(declared.id),
      bytes: 0,
      fileCount: 0,
      bundledOnAndroid: BUNDLED_ANDROID_PACKS.includes(declared.id),
      dependencies: [],
    };
    packs.set(declared.id, {
      ...current,
      label: declared.label ?? current.label,
      bundledOnAndroid: declared.bundledOnAndroid ?? current.bundledOnAndroid,
      dependencies: [...declared.dependencies],
    });
  }

  // RuneWaker dungeon definitions are generated TypeScript rather than part of
  // the WoW JSON catalog. Their matching creature dependency is recoverable
  // from the stable pack namespace without importing runtime code here.
  for (const creaturePack of [...packs.values()].filter((pack) => pack.id.startsWith("creatures:"))) {
    const dungeonPack = packs.get(`dungeon:${creaturePack.id.slice("creatures:".length)}`);
    if (!dungeonPack || dungeonPack.dependencies.includes(creaturePack.id)) continue;
    dungeonPack.dependencies = [...dungeonPack.dependencies, creaturePack.id];
  }

  const sortedPacks = [...packs.values()].sort((left, right) => left.id.localeCompare(right.id));
  for (const pack of sortedPacks) {
    const objects = new Map(files.filter((file) => file.packId === pack.id)
      .map((file) => [file.sha256, file.download?.bytes ?? file.bytes]));
    pack.downloadBytes = [...objects.values()].reduce((sum, bytes) => sum + bytes, 0);
  }
  const version = options.version ?? contentVersion(files, sortedPacks);

  return {
    schemaVersion: CONTENT_SCHEMA_VERSION,
    version,
    createdAt: options.createdAt ?? new Date().toISOString(),
    minimumAppVersion: options.minimumAppVersion ?? DEFAULT_MINIMUM_APP_VERSION,
    packs: sortedPacks,
    files: fileEntries,
  };
}

export function assertCampaignDungeonManifest(manifest, definitions) {
  if (!Array.isArray(definitions) || definitions.length !== WOW_CAMPAIGN_DUNGEON_COUNT) {
    throw new Error(`Release content requires exactly ${WOW_CAMPAIGN_DUNGEON_COUNT} WoW dungeon definitions.`);
  }
  const expectedDefinitions = campaignDungeonPackDefinitions(definitions);
  const manifestPacks = new Map(manifest.packs.map((pack) => [pack.id, pack]));
  if (manifestPacks.size !== manifest.packs.length) {
    throw new Error("Release content manifest contains duplicate pack ids.");
  }

  for (const expected of expectedDefinitions) {
    const actual = manifestPacks.get(expected.id);
    if (!actual) throw new Error(`Release content manifest is missing ${expected.id}.`);
    if (actual.bundledOnAndroid !== expected.bundledOnAndroid
      || actual.dependencies.length !== expected.dependencies.length
      || actual.dependencies.some((dependency, index) => dependency !== expected.dependencies[index])) {
      throw new Error(`Release content manifest has stale dependencies for ${expected.id}.`);
    }
  }

  for (const pack of manifest.packs) {
    const packFiles = Object.values(manifest.files).filter((entry) => entry.packId === pack.id);
    const packBytes = packFiles.reduce((total, entry) => total + entry.bytes, 0);
    if (pack.fileCount !== packFiles.length || pack.bytes !== packBytes) {
      throw new Error(`Release content manifest has invalid file totals for ${pack.id}.`);
    }
    for (const dependency of pack.dependencies) {
      if (!manifestPacks.has(dependency)) {
        throw new Error(`Release content manifest is missing dependency ${dependency} for ${pack.id}.`);
      }
    }
  }

  for (const definition of definitions) {
    const referencedUrls = [
      ...(definition.assets?.visual ?? []).map((asset) => asset.url),
      ...(definition.assets?.collision ?? []).map((asset) => asset.url),
      definition.assets?.navigation?.url,
      ...Object.values(definition.entities ?? {}).map((entity) => entity.visual?.model?.url),
    ].filter(Boolean);
    for (const logicalPath of referencedUrls) {
      if (!manifest.files[logicalPath]) {
        throw new Error(`Release content manifest is missing ${definition.id} asset ${logicalPath}.`);
      }
    }
  }

  const dungeonPackCount = definitions.filter((definition) => (
    manifestPacks.has(`dungeon:${definition.id}`)
  )).length;
  if (dungeonPackCount !== WOW_CAMPAIGN_DUNGEON_COUNT) {
    throw new Error(
      `Release content manifest contains ${dungeonPackCount}/${WOW_CAMPAIGN_DUNGEON_COUNT} WoW dungeon packs.`,
    );
  }
}

async function replaceJsonAtomically(destination, value) {
  const temporary = `${destination}.${process.pid}.${Date.now()}.tmp`;
  await writeFile(temporary, `${JSON.stringify(value, null, 2)}\n`, "utf8");
  await rename(temporary, destination);
}

export async function publishContent(options = {}) {
  const contentDirectory = path.resolve(options.contentDirectory ?? process.env.CONTENT_DIR ?? path.join(PROJECT_ROOT, "content"));
  const files = await scanContentSources(options.sources ?? DEFAULT_CONTENT_SOURCES);
  const includeCampaignPacks = options.includeCampaignPacks !== false;
  const campaignDefinitions = includeCampaignPacks ? await loadCampaignDungeonDefinitions() : null;
  const campaignPackDefinitions = campaignDefinitions
    ? campaignDungeonPackDefinitions(campaignDefinitions)
    : [];
  const packDefinitions = [
    ...campaignPackDefinitions,
    ...(campaignDefinitions ? [RANDOMIZED_BITE_SIZED_PACK_DEFINITION] : []),
    ...(options.packDefinitions ?? []),
  ];
  if (campaignDefinitions) assertCampaignDungeonManifest(createContentManifest(files, { ...options, packDefinitions }), campaignDefinitions);

  const objectDirectory = path.join(contentDirectory, "objects");
  const manifestDirectory = path.join(contentDirectory, "manifests");
  await mkdir(objectDirectory, { recursive: true });
  await mkdir(manifestDirectory, { recursive: true });
  const prepared = await prepareContentObjects(files, {
    directory: objectDirectory,
    baseUrl: String(options.baseUrl ?? "/content/objects").replace(/\/+$/, ""),
    keepOriginal: true,
  });
  const manifest = createContentManifest(prepared.files, { ...options, packDefinitions });
  await replaceJsonAtomically(path.join(manifestDirectory, `${manifest.version}.json`), manifest);
  await replaceJsonAtomically(path.join(contentDirectory, "manifest.json"), manifest);
  return {
    contentDirectory,
    copiedObjects: prepared.writtenObjects,
    storage: { logicalBytes: prepared.logicalBytes, uniqueBytes: prepared.uniqueBytes, storedBytes: prepared.storedBytes },
    manifest,
    campaignDungeonPackCount: campaignDefinitions?.length ?? 0,
  };
}

function parseCliArguments(argv) {
  const options = {};
  for (let index = 0; index < argv.length; index += 1) {
    const value = argv[index];
    if (value === "--content-dir") options.contentDirectory = argv[++index];
    else if (value === "--base-url") options.baseUrl = argv[++index];
    else if (value === "--minimum-app-version") options.minimumAppVersion = argv[++index];
    else throw new Error(`Unknown content publishing argument: ${value}`);
  }
  return options;
}

if (process.argv[1] && path.resolve(process.argv[1]) === fileURLToPath(import.meta.url)) {
  const result = await publishContent(parseCliArguments(process.argv.slice(2)));
  const bytes = result.manifest.packs.reduce((total, pack) => total + pack.bytes, 0);
  console.log(`Published ${result.manifest.files ? Object.keys(result.manifest.files).length : 0} files (${bytes} bytes)`);
  console.log(`Content version: ${result.manifest.version}`);
  console.log(`WoW campaign dungeon packs: ${result.campaignDungeonPackCount}/${WOW_CAMPAIGN_DUNGEON_COUNT}`);
  console.log(`New immutable objects: ${result.copiedObjects}`);
  console.log(`Manifest: ${path.join(result.contentDirectory, "manifest.json")}`);
}