"""Utility functions for the Sound Recordings Takedown process."""

from datetime import datetime
from email import encoders
from email.mime.base import MIMEBase
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
import hashlib
import os

import boto3
import config
import pandas as pd
from src.utils import constants

logger = config.setup_logger(__name__)
s3_client = boto3.client('s3', region_name=config.AWS_REGION)
ses_client = boto3.client('ses', region_name=config.AWS_REGION)


def upload_to_s3(file_path: str, bucket: str, prefix: str) -> None:
    """Upload a local file to S3.

    Args:
        file_path (str): Local path of the file to upload.
        bucket (str): S3 bucket name.
        prefix (str): S3 key prefix (directory).
    """
    try:
        filename = os.path.basename(file_path)
        key = f'{prefix.rstrip("/")}/{filename}'
        s3_client.upload_file(
            Filename=file_path, Bucket=bucket,
            Key=key, ExtraArgs={
                'ExpectedBucketOwner': config.S3_EXPECTED_OWNER
            }
        )
    except Exception as e:
        logger.exception(f'Failed to upload {file_path} to s3://{bucket}/{prefix}: {e}')
        raise


def export_and_upload(takedown_df: pd.DataFrame, isrc_track_df: pd.DataFrame, output_file: str) -> None:
    """Save DataFrames to an Excel file and upload to S3."""
    try:
        os.makedirs(os.path.dirname(output_file), exist_ok=True)
        with pd.ExcelWriter(output_file, engine='openpyxl') as writer:
            takedown_df.to_excel(writer, sheet_name='sheet1', index=False)
            isrc_track_df.to_excel(writer, sheet_name='sheet2', index=False)
        upload_to_s3(output_file, config.S3_BUCKET, config.S3_TMP_FILE_DIR)
    except Exception as e:
        logger.exception(f'Failed to export and upload {output_file}: {e}')
        raise


def send_success_email(filepath: str, filename: str) -> None:
    """Send a success email with Excel file attachment."""
    try:
        with open(filepath, 'rb') as f:
            xlsx_data = f.read()

        file_size = f'{len(xlsx_data) / float(1 << 10):,.0f} KB'
        md5 = hashlib.md5(xlsx_data).hexdigest()
        current_time = datetime.now().astimezone().strftime('%a %b %d %H:%M:%S %Z %Y')

        subject = (
            constants.SUCCESS_EMAIL_SUBJECT
            if config.ENVIRONMENT == config.PROD_ENVIRONMENT
            else f'{constants.SUCCESS_EMAIL_SUBJECT} ({config.ENVIRONMENT.upper()})'
        )
        registry_note = '' if config.SEND_UPCS_TO_MASTERS_REGISTRY else constants.REGISTRY_SKIPPED_NOTE
        message_body = constants.SUCCESS_MESSAGE_BODY.format(
            registry_note=registry_note,
            filename=filename,
            md5=md5,
            file_size=file_size,
            current_time=current_time,
        )

        msg = MIMEMultipart('mixed')
        msg['Subject'] = subject
        msg['From'] = config.EMAIL_SENDER
        msg['To'] = config.EMAIL_RECIPIENTS[0]

        msg.attach(MIMEText(message_body, 'plain', 'utf-8'))

        xlsx_mime = MIMEBase(
            'application',
            'vnd.openxmlformats-officedocument.spreadsheetml.sheet'
        )
        xlsx_mime.set_payload(xlsx_data)
        encoders.encode_base64(xlsx_mime)
        xlsx_mime.add_header(
            'Content-Disposition',
            f'attachment; filename="{filename}"'
        )
        msg.attach(xlsx_mime)

        ses_client.send_raw_email(
            Source=config.EMAIL_SENDER,
            Destinations=config.EMAIL_RECIPIENTS,
            RawMessage={'Data': msg.as_string()},
        )
        logger.info(f'Success email sent with attachment: {filename}')
    except Exception as e:
        logger.exception(f'Failed to send success email for file: {filename} due to: {e}')
        raise