"""Google Drive backed shared-state utilities."""

from __future__ import annotations

import base64
import json
import logging
import os
import sqlite3
import threading
import time
from pathlib import Path
from typing import Any

import requests


def _safe_name(value: str, default: str = "item") -> str:
    text = str(value or "").strip() or default
    return "".join(ch if ch.isalnum() or ch in {"-", "_", "."} else "_" for ch in text)[:180]


class GoogleDriveStateClient:
    def __init__(self, logger: logging.Logger) -> None:
        self.logger = logger
        self._folder_cache: dict[str, str] = {}
        self._file_cache: dict[str, str] = {}
        self._bootstrap_lock = threading.Lock()
        self._bootstrap_loaded_at = 0.0
        self._bootstrap_payload: dict[str, Any] = {}

    def _bootstrap_url(self) -> str:
        return str(os.getenv("GOOGLE_DRIVE_BOOTSTRAP_URL", "") or os.getenv("KAPO_BOOTSTRAP_URL", "") or "").strip()

    def _bootstrap_ttl(self) -> float:
        return float(os.getenv("GOOGLE_DRIVE_BOOTSTRAP_TTL_SEC", "300") or 300)

    def _apply_bootstrap_payload(self, payload: dict[str, Any]) -> None:
        mappings = {
            "shared_state_backend": "KAPO_SHARED_STATE_BACKEND",
            "shared_state_folder_id": "GOOGLE_DRIVE_SHARED_STATE_FOLDER_ID",
            "shared_state_prefix": "GOOGLE_DRIVE_SHARED_STATE_PREFIX",
            "storage_folder_id": "GOOGLE_DRIVE_STORAGE_FOLDER_ID",
            "storage_prefix": "GOOGLE_DRIVE_STORAGE_PREFIX",
            "access_token": "GOOGLE_DRIVE_ACCESS_TOKEN",
            "refresh_token": "GOOGLE_DRIVE_REFRESH_TOKEN",
            "client_secret_json": "GOOGLE_DRIVE_CLIENT_SECRET_JSON",
            "client_secret_json_base64": "GOOGLE_DRIVE_CLIENT_SECRET_JSON_BASE64",
            "client_secret_path": "GOOGLE_DRIVE_CLIENT_SECRET_PATH",
            "token_expires_at": "GOOGLE_DRIVE_TOKEN_EXPIRES_AT",
            "firebase_enabled": "FIREBASE_ENABLED",
            "executor_url": "EXECUTOR_URL",
            "executor_public_url": "EXECUTOR_PUBLIC_URL",
            "ngrok_authtoken": "NGROK_AUTHTOKEN",
            "brain_public_url": "BRAIN_PUBLIC_URL",
            "brain_roles": "BRAIN_ROLES",
            "brain_languages": "BRAIN_LANGUAGES",
        }
        for key, env_name in mappings.items():
            value = payload.get(key)
            if value not in (None, ""):
                os.environ[env_name] = str(value)

    def ensure_bootstrap_loaded(self, force: bool = False) -> dict[str, Any]:
        bootstrap_url = self._bootstrap_url()
        if not bootstrap_url:
            return {}
        now = time.time()
        if not force and self._bootstrap_payload and (now - self._bootstrap_loaded_at) < self._bootstrap_ttl():
            return dict(self._bootstrap_payload)
        with self._bootstrap_lock:
            now = time.time()
            if not force and self._bootstrap_payload and (now - self._bootstrap_loaded_at) < self._bootstrap_ttl():
                return dict(self._bootstrap_payload)
            try:
                response = requests.get(bootstrap_url, timeout=20)
                response.raise_for_status()
                payload = dict(response.json() or {})
                self._bootstrap_payload = payload
                self._bootstrap_loaded_at = time.time()
                self._apply_bootstrap_payload(payload)
                return dict(payload)
            except Exception:
                self.logger.warning("Failed to load Google Drive bootstrap manifest", exc_info=True)
                return dict(self._bootstrap_payload)

    def enabled(self) -> bool:
        self.ensure_bootstrap_loaded()
        return bool(self.root_folder_id())

    def root_folder_id(self) -> str:
        return str(
            os.getenv("GOOGLE_DRIVE_SHARED_STATE_FOLDER_ID", "")
            or os.getenv("GOOGLE_DRIVE_STORAGE_FOLDER_ID", "")
            or ""
        ).strip()

    def prefix(self) -> str:
        return str(
            os.getenv("GOOGLE_DRIVE_SHARED_STATE_PREFIX", "")
            or os.getenv("GOOGLE_DRIVE_STORAGE_PREFIX", "")
            or "kapo/shared_state"
        ).strip("/ ")

    def _control_plane_token(self, label: str) -> str:
        candidates = [
            Path.cwd().resolve() / "data" / "local" / "control_plane.db",
            Path.cwd().resolve() / "data" / "drive_cache" / "control_plane.db",
        ]
        for db_path in candidates:
            if not db_path.exists():
                continue
            try:
                conn = sqlite3.connect(db_path)
                conn.row_factory = sqlite3.Row
                row = conn.execute(
                    "SELECT token FROM ngrok_tokens WHERE label = ? AND enabled = 1",
                    (label,),
                ).fetchone()
                conn.close()
                token = str(row["token"]) if row else ""
                if token:
                    return token
            except Exception:
                self.logger.warning("Failed to read Google Drive token from %s", db_path, exc_info=True)
        return ""

    def _client_secret_payload(self) -> dict[str, Any] | None:
        raw = str(os.getenv("GOOGLE_DRIVE_CLIENT_SECRET_JSON", "")).strip()
        raw_b64 = str(os.getenv("GOOGLE_DRIVE_CLIENT_SECRET_JSON_BASE64", "")).strip()
        path = str(os.getenv("GOOGLE_DRIVE_CLIENT_SECRET_PATH", "")).strip()
        if raw:
            try:
                return json.loads(raw)
            except Exception:
                self.logger.warning("Invalid GOOGLE_DRIVE_CLIENT_SECRET_JSON", exc_info=True)
        if raw_b64:
            try:
                return json.loads(base64.b64decode(raw_b64).decode("utf-8"))
            except Exception:
                self.logger.warning("Invalid GOOGLE_DRIVE_CLIENT_SECRET_JSON_BASE64", exc_info=True)
        if path:
            try:
                return json.loads(Path(path).expanduser().read_text(encoding="utf-8"))
            except Exception:
                self.logger.warning("Failed to load Google Drive client secret path %s", path, exc_info=True)
        client_id = str(os.getenv("GOOGLE_DRIVE_CLIENT_ID", "")).strip()
        client_secret = str(os.getenv("GOOGLE_DRIVE_CLIENT_SECRET", "")).strip()
        token_uri = str(os.getenv("GOOGLE_DRIVE_TOKEN_URI", "https://oauth2.googleapis.com/token")).strip()
        if client_id and client_secret:
            return {
                "installed": {
                    "client_id": client_id,
                    "client_secret": client_secret,
                    "token_uri": token_uri,
                }
            }
        return None

    def _oauth_client(self) -> dict[str, str]:
        payload = self._client_secret_payload() or {}
        installed = payload.get("installed") or payload.get("web") or {}
        return {
            "client_id": str(installed.get("client_id") or "").strip(),
            "client_secret": str(installed.get("client_secret") or "").strip(),
            "token_uri": str(installed.get("token_uri") or "https://oauth2.googleapis.com/token").strip(),
        }

    def _refresh_token(self) -> str:
        return str(os.getenv("GOOGLE_DRIVE_REFRESH_TOKEN", "") or self._control_plane_token("google_drive_refresh_token") or "").strip()

    def _access_token(self) -> str:
        token = str(os.getenv("GOOGLE_DRIVE_ACCESS_TOKEN", "") or self._control_plane_token("google_drive_access_token") or "").strip()
        expires_at = float(str(os.getenv("GOOGLE_DRIVE_TOKEN_EXPIRES_AT", "0") or "0") or 0)
        if token and (not expires_at or expires_at > (time.time() + 60)):
            return token
        refreshed = self._refresh_access_token()
        return refreshed or token

    def _refresh_access_token(self) -> str:
        refresh_token = self._refresh_token()
        client = self._oauth_client()
        if not refresh_token or not client["client_id"] or not client["client_secret"]:
            return ""
        response = requests.post(
            client["token_uri"],
            data={
                "grant_type": "refresh_token",
                "refresh_token": refresh_token,
                "client_id": client["client_id"],
                "client_secret": client["client_secret"],
            },
            timeout=30,
        )
        response.raise_for_status()
        payload = response.json()
        access_token = str(payload.get("access_token") or "").strip()
        expires_in = float(payload.get("expires_in") or 0)
        if access_token:
            os.environ["GOOGLE_DRIVE_ACCESS_TOKEN"] = access_token
            os.environ["GOOGLE_DRIVE_TOKEN_EXPIRES_AT"] = str(time.time() + expires_in) if expires_in else "0"
        return access_token

    def _request(self, method: str, url: str, *, headers: dict[str, str] | None = None, timeout: int = 60, **kwargs) -> requests.Response:
        token = self._access_token()
        if not token:
            raise ValueError("Google Drive access token is not configured")
        base_headers = dict(headers or {})
        response: requests.Response | None = None
        for _ in range(2):
            response = requests.request(
                method,
                url,
                headers={**base_headers, "Authorization": f"Bearer {token}"},
                timeout=timeout,
                **kwargs,
            )
            if response.status_code != 401:
                response.raise_for_status()
                return response
            token = self._refresh_access_token()
            if not token:
                break
        assert response is not None
        response.raise_for_status()
        return response

    @staticmethod
    def _escape_query(value: str) -> str:
        return str(value or "").replace("\\", "\\\\").replace("'", "\\'")

    def _find_folder(self, name: str, parent_id: str) -> str:
        query = (
            "mimeType = 'application/vnd.google-apps.folder' and trashed = false "
            f"and name = '{self._escape_query(name)}'"
        )
        if parent_id:
            query += f" and '{self._escape_query(parent_id)}' in parents"
        response = self._request(
            "GET",
            "https://www.googleapis.com/drive/v3/files",
            params={"q": query, "fields": "files(id,name)", "pageSize": 10, "supportsAllDrives": "true"},
        )
        files = response.json().get("files", [])
        return str(files[0].get("id") or "").strip() if files else ""

    def _create_folder(self, name: str, parent_id: str) -> str:
        payload: dict[str, Any] = {"name": name, "mimeType": "application/vnd.google-apps.folder"}
        if parent_id:
            payload["parents"] = [parent_id]
        response = self._request(
            "POST",
            "https://www.googleapis.com/drive/v3/files?supportsAllDrives=true",
            headers={"Content-Type": "application/json; charset=UTF-8"},
            json=payload,
        )
        return str(response.json().get("id") or "").strip()

    def _ensure_folder_path(self, relative_path: str) -> str:
        current_parent = self.root_folder_id()
        parts = [part for part in f"{self.prefix()}/{relative_path}".replace("\\", "/").split("/") if part.strip()]
        for part in parts:
            safe_part = _safe_name(part, "folder")
            cache_key = f"{current_parent}:{safe_part}"
            cached = self._folder_cache.get(cache_key)
            if cached:
                current_parent = cached
                continue
            folder_id = self._find_folder(safe_part, current_parent)
            if not folder_id:
                folder_id = self._create_folder(safe_part, current_parent)
            self._folder_cache[cache_key] = folder_id
            current_parent = folder_id
        return current_parent

    def _find_file(self, folder_id: str, file_name: str) -> str:
        cache_key = f"{folder_id}:{file_name}"
        cached = self._file_cache.get(cache_key)
        if cached:
            return cached
        query = (
            "trashed = false "
            f"and name = '{self._escape_query(file_name)}' "
            f"and '{self._escape_query(folder_id)}' in parents"
        )
        response = self._request(
            "GET",
            "https://www.googleapis.com/drive/v3/files",
            params={"q": query, "fields": "files(id,name)", "pageSize": 10, "supportsAllDrives": "true"},
        )
        files = response.json().get("files", [])
        file_id = str(files[0].get("id") or "").strip() if files else ""
        if file_id:
            self._file_cache[cache_key] = file_id
        return file_id

    def _create_file(self, folder_id: str, file_name: str) -> str:
        response = self._request(
            "POST",
            "https://www.googleapis.com/drive/v3/files?supportsAllDrives=true",
            headers={"Content-Type": "application/json; charset=UTF-8"},
            json={"name": file_name, "parents": [folder_id]},
        )
        file_id = str(response.json().get("id") or "").strip()
        if file_id:
            self._file_cache[f"{folder_id}:{file_name}"] = file_id
        return file_id

    def _upload_json(self, file_id: str, payload: dict[str, Any]) -> None:
        self._request(
            "PATCH",
            f"https://www.googleapis.com/upload/drive/v3/files/{file_id}?uploadType=media&supportsAllDrives=true",
            headers={"Content-Type": "application/json; charset=UTF-8"},
            data=json.dumps(payload, ensure_ascii=False, sort_keys=True).encode("utf-8"),
        )

    def _download_json(self, file_id: str) -> dict[str, Any]:
        response = self._request(
            "GET",
            f"https://www.googleapis.com/drive/v3/files/{file_id}?alt=media&supportsAllDrives=true",
        )
        return dict(response.json() or {})

    def get_document(self, collection: str, doc_id: str) -> dict[str, Any]:
        if not self.enabled():
            return {}
        folder_id = self._ensure_folder_path(_safe_name(collection, "collection"))
        file_name = f"{_safe_name(doc_id)}.json"
        file_id = self._find_file(folder_id, file_name)
        if not file_id:
            return {}
        try:
            payload = self._download_json(file_id)
            payload.setdefault("id", _safe_name(doc_id))
            return payload
        except Exception:
            self.logger.warning("Failed to download shared-state file %s/%s", collection, doc_id, exc_info=True)
            return {}

    def set_document(self, collection: str, doc_id: str, payload: dict[str, Any], *, merge: bool = True) -> bool:
        if not self.enabled():
            return False
        safe_doc = _safe_name(doc_id)
        try:
            existing = self.get_document(collection, safe_doc) if merge else {}
            combined = {**existing, **dict(payload or {})} if merge else dict(payload or {})
            combined.setdefault("id", safe_doc)
            folder_id = self._ensure_folder_path(_safe_name(collection, "collection"))
            file_name = f"{safe_doc}.json"
            file_id = self._find_file(folder_id, file_name)
            if not file_id:
                file_id = self._create_file(folder_id, file_name)
            self._upload_json(file_id, combined)
            return True
        except Exception:
            self.logger.warning("Failed to upload shared-state file %s/%s", collection, safe_doc, exc_info=True)
            return False

    def list_documents(self, collection: str, *, limit: int = 200) -> list[dict[str, Any]]:
        if not self.enabled():
            return []
        try:
            folder_id = self._ensure_folder_path(_safe_name(collection, "collection"))
            query = f"trashed = false and '{self._escape_query(folder_id)}' in parents"
            response = self._request(
                "GET",
                "https://www.googleapis.com/drive/v3/files",
                params={
                    "q": query,
                    "fields": "files(id,name,modifiedTime)",
                    "pageSize": max(1, int(limit)),
                    "supportsAllDrives": "true",
                    "orderBy": "modifiedTime desc",
                },
            )
            items: list[dict[str, Any]] = []
            for file in response.json().get("files", []):
                file_id = str(file.get("id") or "").strip()
                file_name = str(file.get("name") or "").strip()
                if not file_id or not file_name.endswith(".json"):
                    continue
                self._file_cache[f"{folder_id}:{file_name}"] = file_id
                payload = self._download_json(file_id)
                payload.setdefault("id", file_name[:-5])
                items.append(payload)
            return items
        except Exception:
            self.logger.warning("Failed to list shared-state collection %s", collection, exc_info=True)
            return []

    def delete_document(self, collection: str, doc_id: str) -> bool:
        if not self.enabled():
            return False
        safe_doc = _safe_name(doc_id)
        try:
            folder_id = self._ensure_folder_path(_safe_name(collection, "collection"))
            file_name = f"{safe_doc}.json"
            file_id = self._find_file(folder_id, file_name)
            if not file_id:
                return True
            self._request(
                "DELETE",
                f"https://www.googleapis.com/drive/v3/files/{file_id}?supportsAllDrives=true",
            )
            self._file_cache.pop(f"{folder_id}:{file_name}", None)
            return True
        except Exception:
            self.logger.warning("Failed to delete shared-state file %s/%s", collection, safe_doc, exc_info=True)
            return False