#!/usr/bin/env python3
"""deepdive_delivery.py — Phase 5: Telegram voice message delivery.

Issue: #830 (the-nexus)
Delivers synthesized audio briefing as Telegram voice message.
"""

import argparse
import json
import os
import sys
from pathlib import Path
import urllib.request


class TelegramDeliveryAdapter:
    """Deliver audio briefing via Telegram bot as voice message."""
    
    def __init__(self, bot_token: str, chat_id: str):
        self.bot_token = bot_token
        self.chat_id = chat_id
        self.api_base = f"https://api.telegram.org/bot{bot_token}"
    
    def _api_post(self, method: str, data: dict, files: dict = None):
        """Call Telegram Bot API."""
        import urllib.request
        import urllib.parse
        
        url = f"{self.api_base}/{method}"
        
        if files:
            # Multipart form for file uploads
            boundary = "----DeepDiveBoundary"
            body_parts = []
            
            for key, value in data.items():
                body_parts.append(f'--{boundary}\r\nContent-Disposition: form-data; name="{key}"\r\n\r\n{value}\r\n')
            
            for key, (filename, content) in files.items():
                body_parts.append(
                    f'--{boundary}\r\n'
                    f'Content-Disposition: form-data; name="{key}"; filename="{filename}"\r\n'
                    f'Content-Type: audio/mpeg\r\n\r\n'
                )
                body_parts.append(content)
                body_parts.append(f'\r\n')
            
            body_parts.append(f'--{boundary}--\r\n')
            
            body = b""
            for part in body_parts:
                if isinstance(part, str):
                    body += part.encode()
                else:
                    body += part
            
            req = urllib.request.Request(url, data=body, method="POST")
            req.add_header("Content-Type", f"multipart/form-data; boundary={boundary}")
        else:
            body = urllib.parse.urlencode(data).encode()
            req = urllib.request.Request(url, data=body, method="POST")
            req.add_header("Content-Type", "application/x-www-form-urlencoded")
        
        try:
            with urllib.request.urlopen(req, timeout=60) as resp:
                return json.loads(resp.read().decode())
        except urllib.error.HTTPError as e:
            error_body = e.read().decode()
            raise RuntimeError(f"Telegram API error: {e.code} - {error_body}")
    
    def send_voice(self, audio_path: Path, caption: str = None) -> dict:
        """Send audio file as voice message."""
        audio_bytes = audio_path.read_bytes()
        
        files = {"voice": (audio_path.name, audio_bytes)}
        data = {"chat_id": self.chat_id}
        if caption:
            data["caption"] = caption[:1024]  # Telegram caption limit
        
        result = self._api_post("sendVoice", data, files)
        
        if not result.get("ok"):
            raise RuntimeError(f"Telegram send failed: {result}")
        
        return result
    
    def send_text_preview(self, text: str) -> dict:
        """Send text summary before voice (optional)."""
        data = {
            "chat_id": self.chat_id,
            "text": text[:4096]  # Telegram message limit
        }
        return self._api_post("sendMessage", data)


def load_config():
    """Load Telegram configuration from environment."""
    token = os.environ.get("DEEPDIVE_TELEGRAM_BOT_TOKEN") or os.environ.get("TELEGRAM_BOT_TOKEN")
    chat_id = os.environ.get("DEEPDIVE_TELEGRAM_CHAT_ID") or os.environ.get("TELEGRAM_CHAT_ID")
    
    if not token:
        raise RuntimeError(
            "Telegram bot token required. Set DEEPDIVE_TELEGRAM_BOT_TOKEN or TELEGRAM_BOT_TOKEN"
        )
    if not chat_id:
        raise RuntimeError(
            "Telegram chat ID required. Set DEEPDIVE_TELEGRAM_CHAT_ID or TELEGRAM_CHAT_ID"
        )
    
    return token, chat_id


def main():
    parser = argparse.ArgumentParser(description="Deep Dive Delivery Pipeline")
    parser.add_argument("--audio", "-a", help="Path to audio file (MP3)")
    parser.add_argument("--text", "-t", help="Text message to send")
    parser.add_argument("--caption", "-c", help="Caption for voice message")
    parser.add_argument("--preview-text", help="Optional text preview sent before voice")
    parser.add_argument("--bot-token", help="Telegram bot token (overrides env)")
    parser.add_argument("--chat-id", help="Telegram chat ID (overrides env)")
    parser.add_argument("--dry-run", action="store_true", help="Validate config without sending")
    args = parser.parse_args()
    
    # Load config
    try:
        if args.bot_token and args.chat_id:
            token, chat_id = args.bot_token, args.chat_id
        else:
            token, chat_id = load_config()
    except RuntimeError as e:
        print(f"[ERROR] {e}", file=sys.stderr)
        sys.exit(1)
    
    # Validate input
    if not args.audio and not args.text:
        print("[ERROR] Either --audio or --text required", file=sys.stderr)
        sys.exit(1)
    
    if args.dry_run:
        print(f"[DRY RUN] Config valid")
        print(f"  Bot: {token[:10]}...")
        print(f"  Chat: {chat_id}")
        if args.audio:
            audio_path = Path(args.audio)
            print(f"  Audio: {audio_path} ({audio_path.stat().st_size} bytes)")
        if args.text:
            print(f"  Text: {args.text[:100]}...")
        sys.exit(0)
    
    # Deliver
    adapter = TelegramDeliveryAdapter(token, chat_id)
    
    # Send text if provided
    if args.text:
        print("[DELIVERY] Sending text message...")
        result = adapter.send_text_preview(args.text)
        message_id = result["result"]["message_id"]
        print(f"[DELIVERY] Text sent! Message ID: {message_id}")
    
    # Send audio if provided
    if args.audio:
        audio_path = Path(args.audio)
        if not audio_path.exists():
            print(f"[ERROR] Audio file not found: {audio_path}", file=sys.stderr)
            sys.exit(1)
        
        if args.preview_text:
            print("[DELIVERY] Sending text preview...")
            adapter.send_text_preview(args.preview_text)
        
        print(f"[DELIVERY] Sending voice message: {audio_path}...")
        result = adapter.send_voice(audio_path, args.caption)
        
        message_id = result["result"]["message_id"]
        print(f"[DELIVERY] Voice sent! Message ID: {message_id}")
        
        print(json.dumps({
            "success": True,
            "message_id": message_id,
            "chat_id": chat_id,
            "audio_size_bytes": audio_path.stat().st_size
        }))


if __name__ == "__main__":
    main()