#!/usr/bin/env python3
"""
symlink_models.py — place this file and tags.json in the "Sven Co-op" root folder.

Creates a relative symlink for every model:
  svencoop_addon/models/player/<id>/<id>.mdl  ->  ../../../../svencoop/models/player/helmet/helmet.mdl

Sources (pick one, or combine):
  default          — model IDs from tags.json, grouped by category
  --server PATH    — scan any svencoop_addon/models/player/ directory for .mdl files
  --from-file FILE — read one model ID per line from a text file

Windows: requires Developer Mode or Administrator privileges to create symlinks.

Dump server model IDs to a file (run on the server or over a mount):
  find /home/svenserver/serverfiles/svencoop_addon/models/player \\
       -mindepth 2 -maxdepth 2 -name "*.mdl" -printf "%f\\n" | sed 's/\\.mdl$//' > server_models.txt
"""

import argparse
import json
import os
import sys
from pathlib import Path

HELMET_REL     = Path("svencoop") / "models" / "player" / "helmet" / "helmet.mdl"
MODELS_REL     = Path("svencoop_addon") / "models" / "player"
SYMLINK_TARGET = Path("..") / ".." / ".." / ".." / HELMET_REL


def check_windows_symlink_privilege():
    if os.name != "nt":
        return True
    import ctypes
    try:
        return ctypes.windll.shell32.IsUserAnAdmin() != 0
    except Exception:
        return False


def symlink_one(model_id: str, models_root: Path, target_str: str, dry_run: bool) -> str:
    """Create/update symlink for one model_id. Returns 'created', 'replaced', 'skipped', 'error'."""
    model_dir = models_root / model_id
    mdl_path  = model_dir / f"{model_id}.mdl"

    if not model_dir.is_dir() and not dry_run:
        model_dir.mkdir(parents=True, exist_ok=True)

    if mdl_path.is_symlink():
        if os.readlink(mdl_path) == target_str:
            return "skipped"
        if not dry_run:
            mdl_path.unlink()
        print(f"  replace : {model_id}")
        return "replaced"
    elif mdl_path.exists():
        if not dry_run:
            mdl_path.unlink()
        print(f"  replace : {model_id}  (was real file)")
        return "replaced"
    else:
        print(f"  create  : {model_id}")

    if not dry_run:
        try:
            os.symlink(target_str, mdl_path)
        except OSError as exc:
            print(f"  ERROR   : {model_id} — {exc}")
            return "error"
    return "created"


def print_summary(counts: dict, dry_run: bool):
    total  = counts["created"] + counts["replaced"]
    prefix = "[DRY RUN] " if dry_run else ""
    verb   = "would be written" if dry_run else "written"
    print(
        f"\n{prefix}{total} symlinks {verb} "
        f"({counts['created']} new, {counts['replaced']} replaced), "
        f"{counts['skipped']} already correct"
        + (f", {counts['error']} errors" if counts["error"] else "")
    )


def main():
    parser = argparse.ArgumentParser(description="Symlink Sven Co-op player models to helmet.mdl")
    parser.add_argument("--dry-run",    action="store_true", help="Show what would happen without making changes")
    parser.add_argument("--server",     metavar="PATH",      help="Scan a server's svencoop_addon/models/player/ directory")
    parser.add_argument("--from-file",  metavar="FILE",      help="Read model IDs (one per line) from a text file")
    args = parser.parse_args()

    script_dir = Path(__file__).resolve().parent
    helmet_abs = script_dir / HELMET_REL

    if not helmet_abs.exists():
        sys.exit(f"helmet.mdl not found at {helmet_abs}\nAre you running from the Sven Co-op root?")

    if os.name == "nt" and not check_windows_symlink_privilege():
        print(
            "WARNING: On Windows, symlink creation requires either:\n"
            "  • Developer Mode enabled  (Settings > For developers)\n"
            "  • Running this script as Administrator\n"
        )

    models_root = script_dir / MODELS_REL
    target_str  = str(SYMLINK_TARGET)
    counts      = {"created": 0, "replaced": 0, "skipped": 0, "error": 0}

    # --- --server: scan a player/ directory for all .mdl files ---
    if args.server:
        server_root = Path(args.server)
        if not server_root.is_dir():
            sys.exit(f"Server path not found: {server_root}")

        mdl_files = sorted(server_root.rglob("*.mdl"))
        model_ids = sorted({f.stem for f in mdl_files if f.parent != server_root})
        print(f"\n[server] — {len(model_ids)} models found in {server_root}\n")
        for model_id in model_ids:
            result = symlink_one(model_id, models_root, target_str, args.dry_run)
            counts[result] += 1
        print_summary(counts, args.dry_run)
        return

    # --- --from-file: read model IDs from a text file ---
    if args.from_file:
        file_path = Path(args.from_file)
        if not file_path.exists():
            sys.exit(f"File not found: {file_path}")
        model_ids = [line.strip() for line in file_path.read_text().splitlines() if line.strip()]
        print(f"\n[from file] — {len(model_ids)} models in {file_path}\n")
        for model_id in model_ids:
            result = symlink_one(model_id, models_root, target_str, args.dry_run)
            counts[result] += 1
        print_summary(counts, args.dry_run)
        return

    # --- default: tags.json ---
    tags_path = script_dir / "tags.json"
    if not tags_path.exists():
        sys.exit(f"tags.json not found next to script ({tags_path})")

    with open(tags_path, encoding="utf-8") as f:
        tags: dict[str, list[str]] = json.load(f)

    for category, model_ids in tags.items():
        print(f"\n[{category}] — {len(model_ids)} models")
        for model_id in model_ids:
            result = symlink_one(model_id, models_root, target_str, args.dry_run)
            counts[result] += 1

    print_summary(counts, args.dry_run)


if __name__ == "__main__":
    main()