import json
import os
from datetime import datetime, timedelta
from pathlib import Path
from typing import Any

STORAGE_DIR = Path("/data")
SUBMISSIONS_DIR = STORAGE_DIR / "submissions"
LEADERBOARD_FILE = STORAGE_DIR / "leaderboard.jsonl"
RATE_LIMIT_FILE = STORAGE_DIR / "rate_limits.json"

# Seed data bundled with the app (used on first boot)
SEED_LEADERBOARD = Path(__file__).parent.parent / "assets" / "leaderboard.jsonl"


def ensure_dirs():
    STORAGE_DIR.mkdir(parents=True, exist_ok=True)
    SUBMISSIONS_DIR.mkdir(parents=True, exist_ok=True)


def _seed_leaderboard():
    """Copy bundled leaderboard data to /data on first boot."""
    if LEADERBOARD_FILE.exists():
        return
    if SEED_LEADERBOARD.exists():
        import shutil
        shutil.copy(SEED_LEADERBOARD, LEADERBOARD_FILE)
        print(f"[SEED] Copied leaderboard data from {SEED_LEADERBOARD} to {LEADERBOARD_FILE}")


def save_submission(submission_id: str, payload: dict) -> str:
    """Save raw submission JSON to local storage."""
    ensure_dirs()
    file_path = SUBMISSIONS_DIR / f"{submission_id}.json"
    with open(file_path, "w", encoding="utf-8") as f:
        json.dump(payload, f, ensure_ascii=False, indent=2)
    return str(file_path)


def list_submissions() -> list[dict]:
    """List all submission metadata."""
    ensure_dirs()
    results = []
    for f in sorted(SUBMISSIONS_DIR.glob("*.json")):
        try:
            with open(f, "r", encoding="utf-8") as fp:
                data = json.load(fp)
            meta = data.get("meta", {})
            meta["file"] = str(f.name)
            results.append(meta)
        except Exception:
            continue
    return results


def load_leaderboard() -> list[dict]:
    """Load current leaderboard data from local storage."""
    _seed_leaderboard()
    if not LEADERBOARD_FILE.exists():
        return []
    entries = []
    with open(LEADERBOARD_FILE, "r", encoding="utf-8") as f:
        for line in f:
            line = line.strip()
            if line:
                entries.append(json.loads(line))
    return entries


def save_leaderboard(entries: list[dict]) -> None:
    """Overwrite leaderboard file with the current entries."""
    ensure_dirs()
    with open(LEADERBOARD_FILE, "w", encoding="utf-8") as f:
        for entry in entries:
            f.write(json.dumps(entry, ensure_ascii=False) + "\n")


# ---- Rate limiting ----

def check_rate_limit(email: str, cooldown_minutes: int = 60) -> tuple[bool, str]:
    """Check if email is allowed to submit. Returns (allowed, message)."""
    ensure_dirs()
    limits = {}
    if RATE_LIMIT_FILE.exists():
        with open(RATE_LIMIT_FILE, "r", encoding="utf-8") as f:
            limits = json.load(f)

    last_str = limits.get(email)
    if last_str:
        last_time = datetime.fromisoformat(last_str)
        next_allowed = last_time + timedelta(minutes=cooldown_minutes)
        if datetime.utcnow() < next_allowed:
            remaining = int((next_allowed - datetime.utcnow()).total_seconds() / 60)
            return False, f"This email has already submitted within the last hour. Please wait {remaining} minutes."

    return True, ""


def record_submission_time(email: str) -> None:
    """Record the current submission time for an email."""
    ensure_dirs()
    limits = {}
    if RATE_LIMIT_FILE.exists():
        with open(RATE_LIMIT_FILE, "r", encoding="utf-8") as f:
            limits = json.load(f)
    limits[email] = datetime.utcnow().isoformat()
    with open(RATE_LIMIT_FILE, "w", encoding="utf-8") as f:
        json.dump(limits, f, ensure_ascii=False, indent=2)