"""
Google Sheets Data Service
Fetches and syncs data from Gapura irregularity reports
"""

import os
import logging
import hashlib
import re
from io import StringIO
from typing import List, Dict, Any, Optional, TYPE_CHECKING

if TYPE_CHECKING:
    from data.cache_service import CacheService
from google.oauth2.service_account import Credentials
from googleapiclient.discovery import build
from datetime import datetime
import pandas as pd
from dotenv import load_dotenv

logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

env_path = os.path.join(os.path.dirname(__file__), "..", ".env")
if os.path.exists(env_path):
    try:
        with open(env_path, "r", encoding="utf-8") as f:
            content = f.read()
        content_clean = re.sub(
            r"(?ms)^\s*GOOGLE_SHEETS_CREDENTIALS_JSON\s*=\s*\{.*?\}\s*$", "", content
        )
        load_dotenv(stream=StringIO(content_clean))
        logger.info(f"Loaded .env from {env_path} (sanitized)")
    except Exception:
        load_dotenv(env_path)
        logger.info(f"Loaded .env from {env_path}")

CACHE_TTL = int(os.getenv("CACHE_TTL_SECONDS", 300))


class GoogleSheetsService:
    """
    Service for fetching data from Google Sheets with Redis caching
    """

    def __init__(self, cache: Optional["CacheService"] = None):
        self.scopes = ["https://www.googleapis.com/auth/spreadsheets.readonly"]
        self.service = None
        self.cache = cache
        self._authenticate()

    def _authenticate(self):
        """Authenticate with Google Sheets API"""
        try:
            # Get private key from environment
            private_key = os.getenv("GOOGLE_PRIVATE_KEY", "")

            if not private_key:
                raise ValueError("GOOGLE_PRIVATE_KEY not found in environment")

            # The key is stored with literal \n characters, replace with actual newlines
            if "\\n" in private_key:
                private_key = private_key.replace("\\n", "\n")

            # Log key structure (sanitized)
            logger.info(
                f"Private key loaded: {len(private_key)} chars, {private_key.count(chr(10))} newlines"
            )

            # Get credentials from environment
            credentials_info = {
                "type": "service_account",
                "project_id": "elementum-ebook",
                "private_key_id": os.getenv("GOOGLE_PRIVATE_KEY_ID", ""),
                "private_key": private_key,
                "client_email": os.getenv("GOOGLE_SERVICE_ACCOUNT_EMAIL"),
                "client_id": "",
                "auth_uri": "https://accounts.google.com/o/oauth2/auth",
                "token_uri": "https://oauth2.googleapis.com/token",
            }

            credentials = Credentials.from_service_account_info(
                credentials_info, scopes=self.scopes
            )

            self.service = build("sheets", "v4", credentials=credentials)
            logger.info("Successfully authenticated with Google Sheets API")

        except Exception as e:
            logger.error(f"Authentication failed: {str(e)}")
            raise

    def fetch_sheet_data(
        self,
        spreadsheet_id: str,
        sheet_name: str,
        range_str: str = "A1:Z1000",
        bypass_cache: bool = False,
    ) -> List[Dict[str, Any]]:
        """
        Fetch data from a specific sheet with caching

        Args:
            spreadsheet_id: Google Sheet ID
            sheet_name: Sheet tab name (e.g., "NON CARGO", "CGO")
            range_str: Cell range to fetch
            bypass_cache: If True, skip cache and fetch fresh data

        Returns:
            List of dictionaries with row data
        """
        cache_key = self._generate_cache_key(spreadsheet_id, sheet_name, range_str)

        if self.cache and not bypass_cache:
            cached_data = self.cache.get(cache_key)
            if cached_data is not None:
                logger.info(f"Cache hit for {sheet_name}")
                return cached_data

        try:
            range_notation = f"{sheet_name}!{range_str}"

            logger.info(f"Fetching data from {range_notation}")

            result = (
                self.service.spreadsheets()
                .values()
                .get(spreadsheetId=spreadsheet_id, range=range_notation)
                .execute()
            )

            values = result.get("values", [])

            if not values:
                logger.warning(f"No data found in {range_notation}")
                return []

            headers = values[0]
            rows = values[1:]

            data = []
            for i, row in enumerate(rows):
                row_padded = row + [""] * (len(headers) - len(row))

                row_dict = {}
                for j, header in enumerate(headers):
                    clean_header = header.strip().replace(" ", "_").replace("/", "_")
                    row_dict[clean_header] = (
                        row_padded[j] if j < len(row_padded) else ""
                    )

                row_dict["_row_id"] = f"{sheet_name}_{i + 2}"
                row_dict["_sheet_name"] = sheet_name
                data.append(row_dict)

            logger.info(f"Successfully fetched {len(data)} rows from {sheet_name}")

            if self.cache:
                self.cache.set(cache_key, data, CACHE_TTL)
                logger.info(f"Cached data for {sheet_name} (TTL: {CACHE_TTL}s)")

            return data

        except Exception as e:
            logger.error(f"Error fetching sheet data: {str(e)}")
            raise

    def _generate_cache_key(
        self, spreadsheet_id: str, sheet_name: str, range_str: str
    ) -> str:
        """Generate a unique cache key"""
        key_data = f"{spreadsheet_id}:{sheet_name}:{range_str}"
        return f"sheets:{hashlib.md5(key_data.encode()).hexdigest()}"

    def invalidate_cache(self, spreadsheet_id: str, sheet_name: str = None) -> int:
        """Invalidate cache for a spreadsheet or specific sheet"""
        if not self.cache:
            return 0

        if sheet_name:
            pattern = f"sheets:*{sheet_name}*"
        else:
            pattern = f"sheets:*"

        return self.cache.delete_pattern(pattern)

    def fetch_all_sheets(self, spreadsheet_id: str) -> Dict[str, List[Dict]]:
        """
        Fetch data from all sheets

        Returns:
            Dictionary with sheet names as keys
        """
        try:
            # Get sheet metadata
            spreadsheet = (
                self.service.spreadsheets().get(spreadsheetId=spreadsheet_id).execute()
            )

            sheets = spreadsheet.get("sheets", [])
            all_data = {}

            for sheet in sheets:
                sheet_name = sheet["properties"]["title"]

                # Skip empty sheets
                if sheet["properties"]["gridProperties"]["rowCount"] <= 1:
                    logger.info(f"Skipping empty sheet: {sheet_name}")
                    continue

                data = self.fetch_sheet_data(spreadsheet_id, sheet_name)
                all_data[sheet_name] = data

            return all_data

        except Exception as e:
            logger.error(f"Error fetching all sheets: {str(e)}")
            raise

    def to_dataframe(self, data: List[Dict]) -> pd.DataFrame:
        """Convert data to pandas DataFrame"""
        df = pd.DataFrame(data)

        # Convert date column if exists
        date_columns = ["Date_of_Event", "dateOfEvent", "Date"]
        for col in date_columns:
            if col in df.columns:
                df[col] = pd.to_datetime(df[col], errors="coerce")

        return df

    def sync_to_database(self, data: List[Dict], db_connection: Any):
        """
        Sync fetched data to database

        TODO: Implement database sync
        """
        logger.info(f"Syncing {len(data)} records to database")
        # Implementation depends on your database
        pass


class DataPreprocessor:
    """
    Preprocess irregularity report data for ML models
    """

    def __init__(self):
        self.severity_keywords = {
            "high": [
                "damage",
                "torn",
                "broken",
                "emergency",
                "critical",
                "urgent",
                "severe",
            ],
            "medium": ["delay", "late", "wrong", "incorrect", "missing"],
            "low": ["minor", "small", "slight"],
        }

    def clean_text(self, text: str) -> str:
        """Clean and normalize text"""
        if not text:
            return ""

        # Convert to lowercase
        text = text.lower()

        # Remove extra whitespace
        text = " ".join(text.split())

        return text

    def extract_features(self, report: Dict) -> Dict[str, Any]:
        """Extract features from a single report"""

        # Parse date
        date_str = report.get("Date_of_Event", "") or report.get("dateOfEvent", "")
        try:
            date_obj = pd.to_datetime(date_str)
            day_of_week = date_obj.dayofweek
            month = date_obj.month
            is_weekend = day_of_week in [5, 6]
        except:
            day_of_week = 0
            month = 1
            is_weekend = False

        # Text features
        report_text = report.get("Report", "") or report.get("report", "")
        root_cause = report.get("Root_Caused", "") or report.get("rootCause", "")
        action_taken = report.get("Action_Taken", "") or report.get("actionTaken", "")

        cleaned_report = self.clean_text(report_text)

        # Count severity keywords
        severity_score = 0
        for severity, keywords in self.severity_keywords.items():
            for keyword in keywords:
                if keyword in cleaned_report:
                    severity_score += {"high": 3, "medium": 2, "low": 1}[severity]

        return {
            # Time features
            "day_of_week": day_of_week,
            "month": month,
            "is_weekend": is_weekend,
            # Categorical
            "airline": report.get("Airlines", "Unknown"),
            "airline_type": report.get("Jenis_Maskapai", "Unknown"),
            "hub": report.get("HUB", "Unknown"),
            "branch": report.get("Branch", "Unknown"),
            "category": report.get("Irregularity_Complain_Category", "Unknown"),
            "area": report.get("Area", "Unknown"),
            # Text features
            "report_length": len(report_text),
            "report_word_count": len(report_text.split()) if report_text else 0,
            "root_cause_length": len(root_cause),
            "action_taken_length": len(action_taken),
            "severity_keyword_count": severity_score,
            # Binary
            "has_photos": bool(report.get("Upload_Irregularity_Photo", "")),
            "is_cargo": "Cargo" in report.get("Report_Category", ""),
            "is_complaint": report.get("Report_Category", "") == "Complaint",
            "is_closed": report.get("Status", "").lower() == "closed",
            # Raw text for NLP
            "report_text": cleaned_report,
            "root_cause_text": self.clean_text(root_cause),
            "action_taken_text": self.clean_text(action_taken),
            "combined_text": f"{cleaned_report} {self.clean_text(root_cause)} {self.clean_text(action_taken)}",
        }

    def preprocess_batch(self, reports: List[Dict]) -> List[Dict]:
        """Preprocess a batch of reports"""
        return [self.extract_features(report) for report in reports]


# ============== Usage Example ==============

if __name__ == "__main__":
    # Initialize service
    sheets_service = GoogleSheetsService()
    preprocessor = DataPreprocessor()

    # Fetch data
    spreadsheet_id = os.getenv("GOOGLE_SHEET_ID")

    # Fetch NON CARGO sheet
    non_cargo_data = sheets_service.fetch_sheet_data(
        spreadsheet_id=spreadsheet_id, sheet_name="NON CARGO"
    )

    print(f"Fetched {len(non_cargo_data)} rows from NON CARGO")

    # Preprocess first 5 rows
    if non_cargo_data:
        sample_features = preprocessor.preprocess_batch(non_cargo_data[:5])
        print("\nSample features:")
        for i, features in enumerate(sample_features):
            print(f"\nRow {i + 1}:")
            print(f"  Airline: {features['airline']}")
            print(f"  Category: {features['category']}")
            print(f"  Report length: {features['report_length']}")
            print(f"  Severity keywords: {features['severity_keyword_count']}")