from __future__ import annotations

import json
import sqlite3
from datetime import datetime, timezone
from pathlib import Path
from typing import Any

import yaml
from jsonschema import Draft202012Validator

SCHEMA_PATH = Path(__file__).resolve().parent / "hub-registration.schema.yaml"


def _utc_now() -> str:
    return datetime.now(timezone.utc).replace(microsecond=0).isoformat()


def _load_schema() -> dict[str, Any]:
    return yaml.safe_load(SCHEMA_PATH.read_text(encoding="utf-8"))


def _validate(payload: dict[str, Any], schema_ref: str) -> list[str]:
    schema = _load_schema()
    subschema = schema["$defs"][schema_ref]
    validator = Draft202012Validator(subschema)
    return [error.message for error in validator.iter_errors(payload)]


def _row_to_registration(row: sqlite3.Row) -> dict[str, Any]:
    data = json.loads(row["payload"])
    data["registered_at"] = row["registered_at"]
    data["updated_at"] = row["updated_at"]
    return data


def _public_registration(registration: dict[str, Any]) -> dict[str, Any]:
    return {key: value for key, value in registration.items() if key != "auth_env"}


class HubStore:
    def __init__(self, db_path: Path) -> None:
        self.db_path = db_path
        self.db_path.parent.mkdir(parents=True, exist_ok=True)
        self._init_db()

    def _connect(self) -> sqlite3.Connection:
        conn = sqlite3.connect(self.db_path)
        conn.row_factory = sqlite3.Row
        return conn

    def _init_db(self) -> None:
        with self._connect() as conn:
            conn.execute(
                """
                CREATE TABLE IF NOT EXISTS registrations (
                    repo TEXT PRIMARY KEY,
                    payload TEXT NOT NULL,
                    registered_at TEXT NOT NULL,
                    updated_at TEXT NOT NULL
                )
                """
            )

    def list_repos(self) -> list[dict[str, Any]]:
        with self._connect() as conn:
            rows = conn.execute(
                "SELECT * FROM registrations ORDER BY repo"
            ).fetchall()
        return [_public_registration(_row_to_registration(row)) for row in rows]

    def get_repo(self, repo: str) -> dict[str, Any] | None:
        with self._connect() as conn:
            row = conn.execute(
                "SELECT * FROM registrations WHERE repo = ?", (repo,)
            ).fetchone()
        if row is None:
            return None
        return _public_registration(_row_to_registration(row))

    def get_repo_internal(self, repo: str) -> dict[str, Any] | None:
        with self._connect() as conn:
            row = conn.execute(
                "SELECT * FROM registrations WHERE repo = ?", (repo,)
            ).fetchone()
        if row is None:
            return None
        return _row_to_registration(row)

    def create_repo(self, payload: dict[str, Any]) -> dict[str, Any]:
        errors = _validate(payload, "registration_request")
        if errors:
            raise ValueError("; ".join(errors))
        now = _utc_now()
        record: dict[str, Any] = {
            "repo": payload["repo"],
            "url": payload["url"],
            "enabled": payload.get("enabled", True),
            "required": payload.get("required", False),
            "domain": payload["domain"],
            "cache_ttl_seconds": payload.get("cache_ttl_seconds", 86400),
            "auth_header": payload.get("auth_header", "Authorization"),
        }
        for optional in ("description", "auth_env", "registered_by"):
            if payload.get(optional) is not None:
                record[optional] = payload[optional]
        validator = Draft202012Validator(_load_schema())
        full_errors = [
            error.message
            for error in validator.iter_errors(
                {**record, "registered_at": now, "updated_at": now}
            )
        ]
        if full_errors:
            raise ValueError("; ".join(full_errors))

        with self._connect() as conn:
            try:
                conn.execute(
                    """
                    INSERT INTO registrations (repo, payload, registered_at, updated_at)
                    VALUES (?, ?, ?, ?)
                    """,
                    (record["repo"], json.dumps(record), now, now),
                )
            except sqlite3.IntegrityError as exc:
                raise FileExistsError(f"repo already registered: {record['repo']}") from exc
        return _public_registration({**record, "registered_at": now, "updated_at": now})

    def update_repo(self, repo: str, payload: dict[str, Any]) -> dict[str, Any]:
        errors = _validate(payload, "registration_update")
        if errors:
            raise ValueError("; ".join(errors))
        existing = self.get_repo_internal(repo)
        if existing is None:
            raise KeyError(f"repo not found: {repo}")
        updated = {**existing, **{k: v for k, v in payload.items() if v is not None}, "repo": repo}
        now = _utc_now()
        updated["updated_at"] = now
        with self._connect() as conn:
            conn.execute(
                """
                UPDATE registrations
                SET payload = ?, updated_at = ?
                WHERE repo = ?
                """,
                (json.dumps(updated), now, repo),
            )
        return _public_registration(updated)

    def delete_repo(self, repo: str) -> bool:
        with self._connect() as conn:
            cursor = conn.execute(
                "DELETE FROM registrations WHERE repo = ?", (repo,)
            )
        return cursor.rowcount > 0

    def list_repos_internal(self) -> list[dict[str, Any]]:
        with self._connect() as conn:
            rows = conn.execute(
                "SELECT * FROM registrations ORDER BY repo"
            ).fetchall()
        return [_row_to_registration(row) for row in rows]