#!/usr/bin/env python3
"""Scan local plugins, build distributable zips, and emit OSS metadata.

Mirrors the shape of ``generate_oss_metadata.py`` so the resulting
``metadata/plugins/index.json`` is a drop-in product entry for the existing
Downloads page (it iterates ``mainIndex.products`` regardless of product type).

Layout produced under ``--dist``::

    dist/plugins/
        bundle/<plugin_id>/<id>-<version>.zip
        tool/<plugin_id>/<id>-<version>.zip
        index.json

Each plugin is stored under its own directory on the CDN
(``/files/plugins/{kind}/{plugin_id}/…``), not flat under ``{kind}/``.

Each plugin source tree is full-rebuild zipped: this means deletions in the
repo propagate through to OSS on the next run (no stale entries left behind).
Rebuilding the same version overwrites the zip at a stable URL; bump the
plugin version in ``plugin.json`` when you need a distinct release artifact.

A plugin can opt out of publishing by setting ``"publish": false`` in its
``plugin.json``.

Pass ``--only <plugin_id>`` (repeatable) to pack a subset of plugins, e.g.
for a standalone release of a single plugin driven by its own version bump.
Conversely, ``--exclude <plugin_id>`` (repeatable) skips plugins that are
released through their own dedicated pipeline.
"""

from __future__ import annotations

import argparse
import fnmatch
import hashlib
import json
import os
import shutil
import sys
import zipfile
from datetime import datetime, timezone
from pathlib import Path
from typing import Any

KIND_DIRS = ("bundle", "tool", "apps")

EXCLUDE_PATTERNS = (
    "__pycache__",
    "*.pyc",
    "*.pyo",
    ".DS_Store",
    ".git",
    ".gitignore",
    "node_modules",
    ".venv",
    "venv",
    ".pytest_cache",
    ".mypy_cache",
    ".ruff_cache",
    "*.log",
)


def _is_excluded(name: str) -> bool:
    return any(fnmatch.fnmatch(name, pat) for pat in EXCLUDE_PATTERNS)


def _format_size(size_bytes: int) -> str:
    size = float(size_bytes)
    for unit in ("B", "KB", "MB", "GB"):
        if size < 1024.0:
            return f"{size:.1f} {unit}"
        size /= 1024.0
    return f"{size:.1f} TB"


def _sha256_of_file(path: Path) -> str:
    h = hashlib.sha256()
    with path.open("rb") as f:
        for chunk in iter(lambda: f.read(65536), b""):
            h.update(chunk)
    return h.hexdigest()


def _iter_tree_relpaths(plugin_dir: Path) -> list[str]:
    rels: list[str] = []
    for root, dirs, files in os.walk(plugin_dir):
        dirs[:] = [d for d in dirs if not _is_excluded(d)]
        for fname in files:
            if _is_excluded(fname):
                continue
            rels.append(str((Path(root) / fname).relative_to(plugin_dir)))
    rels.sort()
    return rels


def _zip_plugin(plugin_dir: Path, out_zip: Path) -> None:
    out_zip.parent.mkdir(parents=True, exist_ok=True)
    with zipfile.ZipFile(out_zip, "w", zipfile.ZIP_DEFLATED) as zf:
        for rel in _iter_tree_relpaths(plugin_dir):
            zf.write(plugin_dir / rel, f"{plugin_dir.name}/{rel}")


def _read_manifest(plugin_dir: Path) -> dict[str, Any] | None:
    manifest_path = plugin_dir / "plugin.json"
    if not manifest_path.is_file():
        return None
    try:
        with manifest_path.open("r", encoding="utf-8") as f:
            return json.load(f)
    except (OSError, json.JSONDecodeError) as exc:
        print(
            f"WARNING: skipping {plugin_dir} - cannot read plugin.json: {exc}",
            file=sys.stderr,
        )
        return None


def _localized_field(value: Any) -> dict[str, str]:
    """Normalize manifest name/description to ``{zh-CN, en-US}``.

    Accepts a plain string (duplicated to both locales) or a mapping with
    ``zh-CN`` / ``en-US`` (also accepts ``zh`` / ``en`` aliases).
    """
    if isinstance(value, dict):
        zh = str(value.get("zh-CN") or value.get("zh") or "").strip()
        en = str(value.get("en-US") or value.get("en") or "").strip()
        fallback = zh or en
        return {
            "zh-CN": zh or en or fallback,
            "en-US": en or zh or fallback,
        }
    text = str(value or "").strip()
    return {"zh-CN": text, "en-US": text}


def _localized_description(manifest: dict[str, Any]) -> dict[str, str]:
    """CDN metadata description.
    Prefer ``description_i18n``, else ``description``.
    """
    i18n = manifest.get("description_i18n")
    if i18n is not None:
        return _localized_field(i18n)
    return _localized_field(manifest.get("description") or "")


def _normalize_ver(raw: str) -> str:
    """Strip leading 'v' and surrounding whitespace from a version string."""
    s = raw.strip()
    if s.lower().startswith("v"):
        s = s[1:]
    return s


def get_version(manifest: dict[str, Any]) -> dict[str, str] | None:
    """Return a normalized ``qwenpaw_version`` for CDN metadata.

    Strategy:
      1. If the manifest already provides the structured
         ``qwenpaw_version`` field, return it directly — the plugin
         explicitly declares its compatibility.
      2. For legacy plugins that only declare ``min_version`` /
         ``max_version``, synthesize a proper ``qwenpaw_version`` dict
         with ``min`` and/or ``max`` keys so downstream consumers
         (e.g. ``_is_entry_compatible``) always see a consistent
         structure.

    Version strings are sanitized (leading 'v' and whitespace removed).
    Returns ``None`` when no version constraint is declared.
    """
    # --- Case 1: structured field available, use directly ---
    qwenpaw_version = manifest.get("qwenpaw_version")
    if isinstance(qwenpaw_version, dict):
        return {
            k: _normalize_ver(str(v))
            for k, v in qwenpaw_version.items()
            if k in ("min", "max")
        }

    # --- Case 2: legacy min/max, synthesize structured dict ---
    min_ver_str = _normalize_ver(str(manifest.get("min_version") or ""))
    max_ver_str = _normalize_ver(str(manifest.get("max_version") or ""))
    if not min_ver_str and not max_ver_str:
        return None

    result: dict[str, str] = {}
    if min_ver_str:
        result["min"] = min_ver_str
    if max_ver_str:
        result["max"] = max_ver_str
    return result


def _build_metadata(
    manifest: dict[str, Any],
    *,
    file_id: str,
    plugin_id: str,
    version: str,
    kind: str,
    zip_path: Path,
    cdn_path: str,
) -> dict[str, Any]:
    size_bytes = zip_path.stat().st_size
    metadata: dict[str, Any] = {
        "id": file_id,
        "plugin_id": plugin_id,
        "name": _localized_field(manifest.get("name") or plugin_id),
        "description": _localized_description(manifest),
        "product": "plugins",
        "platform": kind,
        "version": version,
        "author": str(manifest.get("author") or ""),
        "filename": zip_path.name,
        "url": cdn_path,
        "size": _format_size(size_bytes),
        "size_bytes": size_bytes,
        "sha256": _sha256_of_file(zip_path),
        "updated_at": datetime.now(timezone.utc).isoformat(),
        "type": "zip",
    }

    version_constraint = get_version(manifest)
    if version_constraint:
        metadata["qwenpaw_version"] = version_constraint

    return metadata


def _matches_only(
    only: list[str] | None,
    plugin_id: str,
    dir_name: str,
) -> bool:
    """True when *only* is unset or matches the plugin id / directory name."""
    if not only:
        return True
    return plugin_id in only or dir_name in only


def _selected(
    only: list[str] | None,
    exclude: list[str] | None,
    plugin_id: str,
    dir_name: str,
) -> bool:
    """Apply ``--only`` / ``--exclude`` selection to a plugin."""
    if exclude and (plugin_id in exclude or dir_name in exclude):
        return False
    return _matches_only(only, plugin_id, dir_name)


def discover_and_pack(
    plugins_root: Path,
    dist_root: Path,
    cdn_prefix: str,
    only: list[str] | None = None,
    exclude: list[str] | None = None,
) -> dict[str, Any]:
    """Scan, zip, and assemble the plugins index. Always full-rebuild."""
    index: dict[str, Any] = {
        "product": "plugins",
        "updated_at": datetime.now(timezone.utc).isoformat(),
        "platforms": {},
        "files": {},
    }

    if not plugins_root.is_dir():
        print(
            f"WARNING: plugins root does not exist: {plugins_root}",
            file=sys.stderr,
        )
        return index

    for kind in KIND_DIRS:
        kind_dir = plugins_root / kind
        if not kind_dir.is_dir():
            continue
        for plugin_dir in sorted(p for p in kind_dir.iterdir() if p.is_dir()):
            manifest = _read_manifest(plugin_dir)
            if manifest is None:
                continue
            if manifest.get("publish") is False:
                print(f"  - skip {plugin_dir.name} (publish=false)")
                continue

            plugin_id = str(manifest.get("id") or plugin_dir.name)
            if not _selected(only, exclude, plugin_id, plugin_dir.name):
                continue
            version = str(manifest.get("version") or "0.0.0")
            zip_name = f"{plugin_id}-{version}.zip"
            zip_path = dist_root / kind / plugin_id / zip_name

            print(
                f"  + pack {kind}/{plugin_dir.name} -> "
                f"{plugin_id}/{zip_path.name}",
            )
            _zip_plugin(plugin_dir, zip_path)

            cdn_path = (
                f"{cdn_prefix.rstrip('/')}/{kind}/{plugin_id}/{zip_name}"
            )
            file_id = f"{plugin_id}-{version}"
            metadata = _build_metadata(
                manifest,
                file_id=file_id,
                plugin_id=plugin_id,
                version=version,
                kind=kind,
                zip_path=zip_path,
                cdn_path=cdn_path,
            )
            index["files"][file_id] = metadata
            kind_entry = index["platforms"].setdefault(kind, {"versions": []})
            if file_id not in kind_entry["versions"]:
                kind_entry["versions"].insert(0, file_id)

    return index


def _dry_run_scan(
    plugins_root: Path,
    only: list[str] | None,
    exclude: list[str] | None,
) -> None:
    """List what would be packed without writing anything."""
    for kind in KIND_DIRS:
        kind_dir = plugins_root / kind
        if not kind_dir.is_dir():
            continue
        for plugin_dir in sorted(
            p for p in kind_dir.iterdir() if p.is_dir()
        ):
            manifest = _read_manifest(plugin_dir)
            if manifest is None:
                continue
            if manifest.get("publish") is False:
                print(f"  - skip {plugin_dir.name} (publish=false)")
                continue
            plugin_id = str(manifest.get("id") or plugin_dir.name)
            if not _selected(only, exclude, plugin_id, plugin_dir.name):
                continue
            print(
                f"  ~ would pack {kind}/{plugin_dir.name} "
                f"(id={manifest.get('id')}, "
                f"version={manifest.get('version')})"
            )
    print("Dry run complete.")


def main() -> int:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument(
        "--plugins-root",
        default="plugins",
        help="Path to the plugins/ directory (default: plugins)",
    )
    parser.add_argument(
        "--dist",
        default="dist/plugins",
        help="Output directory for zip artifacts (default: dist/plugins)",
    )
    parser.add_argument(
        "--metadata-out",
        default=None,
        help=(
            "Where to write the assembled plugins index JSON. "
            "Defaults to <dist>/index.json."
        ),
    )
    parser.add_argument(
        "--cdn-prefix",
        default="/files/plugins",
        help="OSS path prefix used in metadata URLs (default: /files/plugins)",
    )
    parser.add_argument(
        "--only",
        action="append",
        default=None,
        metavar="PLUGIN_ID",
        help=(
            "Pack only the plugin(s) whose manifest id or directory name "
            "matches. Repeatable. Default: pack all plugins."
        ),
    )
    parser.add_argument(
        "--exclude",
        action="append",
        default=None,
        metavar="PLUGIN_ID",
        help=(
            "Skip the plugin(s) whose manifest id or directory name "
            "matches (e.g. plugins with a dedicated release pipeline). "
            "Repeatable."
        ),
    )
    parser.add_argument(
        "--dry-run",
        action="store_true",
        help="Scan + plan only; do not write zips or index.",
    )
    args = parser.parse_args()

    plugins_root = Path(args.plugins_root).resolve()
    dist_root = Path(args.dist).resolve()
    metadata_out = Path(
        args.metadata_out
        if args.metadata_out is not None
        else dist_root / "index.json"
    ).resolve()

    print(f"Scanning plugins under: {plugins_root}")
    if args.dry_run:
        _dry_run_scan(plugins_root, args.only, args.exclude)
        return 0

    if dist_root.exists():
        # Wipe stale zips/dirs so deletions propagate cleanly.
        for kind in KIND_DIRS:
            kind_root = dist_root / kind
            if not kind_root.is_dir():
                continue
            for child in kind_root.iterdir():
                if child.is_file():
                    child.unlink()
                elif child.is_dir():
                    shutil.rmtree(child)
    dist_root.mkdir(parents=True, exist_ok=True)

    index = discover_and_pack(
        plugins_root,
        dist_root,
        args.cdn_prefix,
        only=args.only,
        exclude=args.exclude,
    )

    metadata_out.parent.mkdir(parents=True, exist_ok=True)
    with metadata_out.open("w", encoding="utf-8") as f:
        json.dump(index, f, indent=2, ensure_ascii=False)

    print()
    print(f"Wrote index: {metadata_out}")
    n_files = len(index["files"])
    n_kinds = len(index["platforms"])
    print(f"  {n_files} plugin(s) across {n_kinds} kind(s)")
    return 0


if __name__ == "__main__":
    sys.exit(main())