#!/usr/bin/env python3
from __future__ import annotations

import argparse
import json
import os
import shutil
import socket
import subprocess
import sys
from datetime import datetime, timezone
from pathlib import Path

REPO_ROOT = Path("{{REPO_ROOT}}")
RUNTIME_ROOT = Path("{{RUNTIME_ROOT}}")
INCIDENT_ROOT_DEFAULT = Path("/var/lib/metin/incidents")

sys.path.insert(0, str(REPO_ROOT))

import channel_inventory


def parse_args() -> argparse.Namespace:
    parser = argparse.ArgumentParser(description="Collect a Metin runtime incident bundle")
    parser.add_argument("--tag", default="manual", help="Short incident tag used in the bundle directory name")
    parser.add_argument("--since", default="-30 minutes", help="journalctl --since value")
    parser.add_argument("--output-root", default=str(INCIDENT_ROOT_DEFAULT), help="Incident bundle root directory")
    parser.add_argument("--include-cores", action="store_true", help="Copy matching core files into the bundle")
    return parser.parse_args()


def ensure_root() -> None:
    if os.geteuid() != 0:
        raise SystemExit("Run as root.")


def sanitize_tag(value: str) -> str:
    filtered = "".join(char if char.isalnum() or char in {"-", "_"} else "-" for char in value.strip())
    return filtered or "manual"


def run(command: list[str], check: bool = True) -> subprocess.CompletedProcess[str]:
    return subprocess.run(command, check=check, capture_output=True, text=True)


def write_text(path: Path, content: str) -> None:
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(content, encoding="utf-8")


def write_command_output(bundle_dir: Path, filename: str, command: list[str], check: bool = False) -> None:
    completed = run(command, check=check)
    content = f"$ {' '.join(command)}\n\n"
    if completed.stdout:
        content += completed.stdout
    if completed.stderr:
        content += "\n[stderr]\n" + completed.stderr
    write_text(bundle_dir / filename, content)


def copy_log_tails(bundle_dir: Path) -> None:
    logs_dir = bundle_dir / "logs"
    for path in sorted(RUNTIME_ROOT.glob("channels/**/syslog.log")) + sorted(RUNTIME_ROOT.glob("channels/**/syserr.log")):
        if not path.is_file():
            continue
        relative = path.relative_to(RUNTIME_ROOT)
        destination = logs_dir / relative
        destination.parent.mkdir(parents=True, exist_ok=True)
        completed = run(["tail", "-n", "400", str(path)], check=False)
        content = f"# tail -n 400 {path}\n\n"
        if completed.stdout:
            content += completed.stdout
        if completed.stderr:
            content += "\n[stderr]\n" + completed.stderr
        destination.write_text(content, encoding="utf-8")


def find_core_files() -> list[Path]:
    matches: list[Path] = []
    for path in sorted(RUNTIME_ROOT.glob("channels/**/core*")):
        if path.is_file():
            matches.append(path)
    return matches


def write_core_metadata(bundle_dir: Path, core_files: list[Path]) -> None:
    rows = []
    for path in core_files:
        stat = path.stat()
        rows.append(
            {
                "path": str(path),
                "size_bytes": stat.st_size,
                "mtime": datetime.fromtimestamp(stat.st_mtime, tz=timezone.utc).isoformat(),
            }
        )
    write_text(bundle_dir / "core-files.json", json.dumps(rows, indent=2))


def copy_core_files(bundle_dir: Path, core_files: list[Path]) -> None:
    cores_dir = bundle_dir / "cores"
    for path in core_files:
        relative = path.relative_to(RUNTIME_ROOT)
        destination = cores_dir / relative
        destination.parent.mkdir(parents=True, exist_ok=True)
        shutil.copy2(path, destination)


def git_summary(repo_path: Path) -> dict[str, object]:
    summary: dict[str, object] = {"path": str(repo_path), "present": repo_path.exists()}
    if not repo_path.exists():
        return summary

    head = run(["git", "-C", str(repo_path), "rev-parse", "HEAD"], check=False)
    status = run(["git", "-C", str(repo_path), "status", "--short"], check=False)
    branch = run(["git", "-C", str(repo_path), "rev-parse", "--abbrev-ref", "HEAD"], check=False)
    summary.update(
        {
            "head": head.stdout.strip(),
            "branch": branch.stdout.strip(),
            "dirty": bool(status.stdout.strip()),
            "status": status.stdout.splitlines(),
        }
    )
    return summary


def main() -> int:
    args = parse_args()
    ensure_root()

    timestamp = datetime.now(timezone.utc).strftime("%Y%m%dT%H%M%SZ")
    tag = sanitize_tag(args.tag)
    output_root = Path(args.output_root)
    bundle_dir = output_root / f"{timestamp}-{tag}"
    bundle_dir.mkdir(parents=True, exist_ok=False)
    os.chmod(bundle_dir, 0o700)

    units = [
        channel_inventory.STACK_UNIT,
        channel_inventory.DB_UNIT,
        channel_inventory.DB_READY_UNIT,
        channel_inventory.AUTH_UNIT,
        *channel_inventory.get_game_units(),
    ]

    source_repo = RUNTIME_ROOT.parent.parent / "repos" / "m2dev-server-src"
    runtime_repo = REPO_ROOT
    meta = {
        "created_at": datetime.now(timezone.utc).isoformat(),
        "hostname": socket.gethostname(),
        "runtime_root": str(RUNTIME_ROOT),
        "output_root": str(output_root),
        "tag": tag,
        "since": args.since,
        "repos": {
            "m2dev-server": git_summary(runtime_repo),
            "m2dev-server-src": git_summary(source_repo),
        },
    }
    write_text(bundle_dir / "meta.json", json.dumps(meta, indent=2))

    write_command_output(bundle_dir, "uname.txt", ["uname", "-a"])
    write_command_output(bundle_dir, "df.txt", ["df", "-h"])
    write_command_output(bundle_dir, "free.txt", ["free", "-h"], check=False)
    write_command_output(bundle_dir, "ports.txt", ["ss", "-ltnp"], check=False)
    write_command_output(bundle_dir, "systemctl-status.txt", ["systemctl", "status", "--no-pager", *units], check=False)

    journal_dir = bundle_dir / "journal"
    for unit in units:
        safe_name = unit.replace("@", "_").replace(".", "_")
        write_command_output(
            journal_dir,
            f"{safe_name}.log",
            ["journalctl", "--no-pager", "--since", args.since, "-u", unit],
            check=False,
        )

    copy_log_tails(bundle_dir)

    core_files = find_core_files()
    write_core_metadata(bundle_dir, core_files)
    if args.include_cores and core_files:
        copy_core_files(bundle_dir, core_files)

    print(bundle_dir)
    return 0


if __name__ == "__main__":
    raise SystemExit(main())