# -*- coding: utf-8 -*-
"""Импорт модпаков .mrpack (формат Modrinth) и каталог модпаков.

mrpack — zip с modrinth.index.json: индекс описывает версию Minecraft,
загрузчик (fabric/quilt/forge/neoforge) и список файлов для скачивания;
плюс каталоги overrides/ (client-overrides/) — готовые файлы папки игры.
"""

import json
import os
import zipfile

from . import forge, http, mods
from .java_fetch import _safe_join

PACKS_BASE = "https://pixellauncher.ru/packs"
CATALOG_URL = PACKS_BASE + "/catalog.json"


def fetch_catalog(timeout=15):
    """Каталог модпаков с сайта: [{title, desc, url, mc, loader, size}, ...]."""
    raw = http.get_bytes(CATALOG_URL, timeout=timeout)
    data = json.loads(raw.decode("utf-8"))
    if not isinstance(data, list):
        raise ValueError("пустой каталог модпаков")
    return [x for x in data
            if isinstance(x, dict) and isinstance(x.get("url"), str)
            and x["url"]]


def pack_url(entry):
    """Абсолютный URL пака: относительные пути тянутся с сайта."""
    u = str(entry.get("url") or "").strip()
    if u.startswith(("http://", "https://")):
        return u
    return PACKS_BASE + "/" + u.lstrip("/")


def read_index(path):
    """Читает индекс пака. Возвращает (индекс, mc_ver, loader, loader_ver)."""
    with zipfile.ZipFile(path) as z:
        with z.open("modrinth.index.json") as f:
            data = json.loads(f.read().decode("utf-8"))
    deps = data.get("dependencies") or {}
    mc = deps.get("minecraft") or ""
    loader, loader_ver = "", ""
    if deps.get("fabric-loader"):
        loader, loader_ver = "fabric", deps["fabric-loader"]
    elif deps.get("quilt-loader"):
        loader, loader_ver = "quilt", deps["quilt-loader"]
    elif deps.get("neoforge"):
        loader, loader_ver = "neoforge", deps["neoforge"]
    elif deps.get("forge"):
        loader, loader_ver = "forge", deps["forge"]
    if not mc:
        raise RuntimeError("в паке не указана версия Minecraft")
    return data, mc, loader, loader_ver


def _primary_download(downloads):
    """Достаёт основной файл из "downloads".

    Формат в индексе Modrinth встречается в трёх видах:
      ["https://..."]                      — просто список ссылок,
      [{"hashes": {...}, "url": "...", ...}] — старый формат с объектами,
      {"primary": "https://...", "alternate": [...]} — новый формат.
    """
    if isinstance(downloads, dict):
        downloads = ([downloads.get("primary")] +
                     list(downloads.get("alternate") or []))
    if not downloads:
        return None
    first = downloads[0]
    if isinstance(first, str):
        return {"url": first, "filename": "", "size": 0}
    primary = next((d for d in downloads
                    if isinstance(d, dict) and d.get("primary")), first)
    if not isinstance(primary, dict):
        return None
    return primary


def _files_from_index(index):
    """[(путь_относительно_игры, url, filename, size)] — клиентские файлы."""
    out = []
    for entry in index.get("files") or []:
        env = entry.get("env") or {}
        if env.get("client") == "unsupported":
            continue
        downloads = entry.get("downloads") or []
        if not downloads:
            continue
        primary = _primary_download(downloads)
        if not primary:
            continue
        url = primary.get("url") or ""
        if not url:
            continue
        rel = (entry.get("path") or "").replace("\\", "/")
        if not rel or rel.endswith("/"):
            continue
        out.append((rel, url, primary.get("filename") or rel.rsplit("/", 1)[-1],
                    int(primary.get("size") or entry.get("fileSize") or 0)))
    return out


def install(game_dir, pack_path, log=None, progress=None, cancel=None):
    """Ставит пак в game_dir. Возвращает (id_версии, скачано_файлов).

    progress(fraction) и cancel — как у http.download_file.
    """
    if log:
        log(f"Пак: читаю {os.path.basename(pack_path)}…")
    index, mc, loader, loader_ver = read_index(pack_path)

    files = _files_from_index(index)
    total = sum(max(1, f[3]) for f in files) or 1
    done = 0

    # лоадер
    vid = None
    if loader:
        if log:
            log(f"Пак: Minecraft {mc}, {loader} {loader_ver}")
        if loader in ("fabric", "quilt"):
            vid = mods.install(game_dir, loader, mc, loader_version=loader_ver)
        else:   # forge / neoforge — официальным инсталлятором
            vid = forge.install(game_dir, loader, mc,
                                loader_version=loader_ver or None, log=log)
        done += max(1, total // (len(files) + 2))

    # скачивание файлов
    got = 0
    for rel, url, filename, size in files:
        if cancel is not None and cancel.is_set():
            raise http.Cancelled
        dest = _safe_join(game_dir, rel)
        os.makedirs(os.path.dirname(dest), exist_ok=True)
        if log:
            log(f"Пак: {rel}")
        if http.download_file(url, dest, size=size, cancel=cancel):
            got += 1
        done += max(1, size or 1)
        if progress:
            progress(min(0.95, done / total))

    # overrides
    ov = 0
    with zipfile.ZipFile(pack_path) as z:
        for name in z.namelist():
            target = None
            for prefix in ("overrides/", "client-overrides/"):
                if name.startswith(prefix) and not name.endswith("/"):
                    target = name[len(prefix):]
                    break
            if not target:
                continue
            dest = _safe_join(game_dir, target)
            os.makedirs(os.path.dirname(dest), exist_ok=True)
            with z.open(name) as src, open(dest, "wb") as out:
                out.write(src.read())
            ov += 1
    if log and ov:
        log(f"Пак: распаковано {ov} файлов overrides")
    return vid, got


def install_from_url(game_dir, url, log=None, progress=None, cancel=None, filename_hint="pack.mrpack"):
    """Скачивает модпак по прямой ссылке и устанавливает."""
    import tempfile
    dest = os.path.join(tempfile.gettempdir(), "PixelLauncher",
                        filename_hint.replace("/", "_"))
    os.makedirs(os.path.dirname(dest), exist_ok=True)

    def prog(done_b, total_b):
        if progress and total_b:
            progress(min(0.4, (done_b / total_b) * 0.4))

    http.download_file(url, dest, progress=prog, cancel=cancel)
    def p2(f):
        if progress:
            progress(0.4 + f * 0.6)
    vid, got = install(game_dir, dest, log=log, progress=p2, cancel=cancel)
    try:
        os.unlink(dest)
    except OSError:
        pass
    return vid, got