"""Server sync client for multi-user transcription."""

import requests
import json
import base64
from pathlib import Path
from typing import Optional, List
from datetime import datetime
import threading
import queue
from concurrent.futures import ThreadPoolExecutor


class ServerSyncClient:
    """Client for syncing transcriptions to a multi-user server."""

    def __init__(self, url: str, room: str, passphrase: str, user_name: str,
                 fonts_dir: Optional[Path] = None,
                 font_source: str = "None",
                 websafe_font: Optional[str] = None,
                 google_font: Optional[str] = None,
                 custom_font_file: Optional[str] = None):
        """
        Initialize server sync client.

        Args:
            url: Server URL (e.g., http://example.com/api/send)
            room: Room name
            passphrase: Room passphrase
            user_name: User's display name
            fonts_dir: Optional directory containing custom fonts to upload
            font_source: Font source type ("None", "Web-Safe", "Google Font", "Custom File")
            websafe_font: Web-safe font name (e.g., "Arial", "Times New Roman")
            google_font: Google Font name (e.g., "Roboto", "Open Sans")
            custom_font_file: Path to a custom font file for this speaker
        """
        self.url = url
        self.room = room
        self.passphrase = passphrase
        self.user_name = user_name
        self.fonts_dir = fonts_dir
        self.font_source = font_source
        self.websafe_font = websafe_font
        self.google_font = google_font
        self.custom_font_file = custom_font_file

        # Font info to send with transcriptions
        self.font_family: Optional[str] = None
        self.font_type: Optional[str] = None  # "websafe", "google", "custom"

        # Queue for sending transcriptions asynchronously
        self.send_queue = queue.Queue()
        self.is_running = False
        self.send_thread: Optional[threading.Thread] = None

        # Thread pool for parallel HTTP requests (max 3 concurrent)
        self.executor = ThreadPoolExecutor(max_workers=3)

        # Statistics
        self.sent_count = 0
        self.error_count = 0
        self.last_error: Optional[str] = None

    def start(self):
        """Start the sync client."""
        if self.is_running:
            return

        self.is_running = True
        self.send_thread = threading.Thread(target=self._send_loop, daemon=True)
        self.send_thread.start()
        print(f"Server sync started: room={self.room}")

        # Set up font based on source type
        if self.font_source == "Web-Safe" and self.websafe_font:
            self.font_family = self.websafe_font
            self.font_type = "websafe"
            print(f"Using web-safe font: {self.font_family}")
        elif self.font_source == "Google Font" and self.google_font:
            self.font_family = self.google_font
            self.font_type = "google"
            print(f"Using Google Font: {self.font_family}")
        elif self.font_source == "Custom File" and self.custom_font_file:
            self._upload_custom_font()
        # Legacy fallback: upload all fonts from fonts_dir if available
        elif self.fonts_dir:
            self._upload_fonts()

    def _upload_custom_font(self):
        """Upload the user's custom font file to the server for per-speaker fonts."""
        if not self.custom_font_file:
            return

        font_path = Path(self.custom_font_file)
        if not font_path.exists():
            print(f"Custom font file not found: {self.custom_font_file}")
            return

        # Validate extension
        font_extensions = {'.ttf', '.otf', '.woff', '.woff2'}
        if font_path.suffix.lower() not in font_extensions:
            print(f"Invalid font file type: {font_path.suffix}")
            return

        mime_types = {
            '.ttf': 'font/ttf',
            '.otf': 'font/otf',
            '.woff': 'font/woff',
            '.woff2': 'font/woff2'
        }

        try:
            # Read and encode font data
            with open(font_path, 'rb') as f:
                font_data = base64.b64encode(f.read()).decode('utf-8')

            # Font family name is filename without extension
            self.font_family = font_path.stem
            font_filename = font_path.name

            print(f"Uploading custom font: {font_filename} (family: {self.font_family})")

            # Upload to server
            from urllib.parse import urlparse
            parsed = urlparse(self.url)
            base_url = f"{parsed.scheme}://{parsed.netloc}"
            fonts_url = f"{base_url}/api/fonts"

            response = requests.post(
                fonts_url,
                json={
                    'room': self.room,
                    'passphrase': self.passphrase,
                    'fonts': [{
                        'name': font_filename,
                        'data': font_data,
                        'mime': mime_types.get(font_path.suffix.lower(), 'font/ttf')
                    }]
                },
                timeout=30.0
            )

            if response.status_code == 200:
                result = response.json()
                self.font_type = "custom"
                print(f"Custom font uploaded: {self.font_family}")
            else:
                print(f"Custom font upload failed: {response.status_code}")
                self.font_family = None
                self.font_type = None

        except Exception as e:
            print(f"Error uploading custom font: {e}")
            self.font_family = None
            self.font_type = None

    def _upload_fonts(self):
        """Upload custom fonts to the server."""
        if not self.fonts_dir or not self.fonts_dir.exists():
            return

        # Find font files
        font_extensions = {'.ttf', '.otf', '.woff', '.woff2'}
        font_files = [f for f in self.fonts_dir.iterdir()
                      if f.is_file() and f.suffix.lower() in font_extensions]

        if not font_files:
            return

        # Prepare font data
        fonts = []
        mime_types = {
            '.ttf': 'font/ttf',
            '.otf': 'font/otf',
            '.woff': 'font/woff',
            '.woff2': 'font/woff2'
        }

        for font_file in font_files:
            try:
                with open(font_file, 'rb') as f:
                    font_data = base64.b64encode(f.read()).decode('utf-8')
                fonts.append({
                    'name': font_file.name,
                    'data': font_data,
                    'mime': mime_types.get(font_file.suffix.lower(), 'font/ttf')
                })
                print(f"Prepared font for upload: {font_file.name}")
            except Exception as e:
                print(f"Error reading font file {font_file}: {e}")

        if not fonts:
            return

        # Upload to server
        try:
            # Extract base URL for fonts endpoint
            from urllib.parse import urlparse
            parsed = urlparse(self.url)
            base_url = f"{parsed.scheme}://{parsed.netloc}"
            fonts_url = f"{base_url}/api/fonts"

            response = requests.post(
                fonts_url,
                json={
                    'room': self.room,
                    'passphrase': self.passphrase,
                    'fonts': fonts
                },
                timeout=30.0  # Longer timeout for font uploads
            )

            if response.status_code == 200:
                result = response.json()
                print(f"Fonts uploaded successfully: {result.get('message', '')}")
            else:
                print(f"Font upload failed: {response.status_code}")
        except Exception as e:
            print(f"Error uploading fonts: {e}")

    def stop(self):
        """Stop the sync client."""
        self.is_running = False
        if self.send_thread:
            self.send_thread.join(timeout=2.0)
        # Shutdown executor and wait for pending requests
        self.executor.shutdown(wait=False)  # Don't wait - let pending requests finish in background
        print("Server sync stopped")

    def send_transcription(self, text: str, timestamp: Optional[datetime] = None, is_preview: bool = False):
        """
        Send a transcription to the server (non-blocking).

        Args:
            text: Transcription text
            timestamp: Timestamp (defaults to now)
            is_preview: Whether this is a preview transcription
        """
        if timestamp is None:
            timestamp = datetime.now()

        # Debug: Log when transcription is queued
        import time
        queue_time = time.time()

        # Add to queue
        self.send_queue.put({
            'text': text,
            'timestamp': timestamp.strftime("%H:%M:%S"),
            'is_preview': is_preview,
            'queue_time': queue_time  # For debugging
        })

    def send_preview(self, text: str, timestamp: Optional[datetime] = None):
        """
        Send a preview transcription to the server (non-blocking).

        Args:
            text: Preview transcription text
            timestamp: Timestamp (defaults to now)
        """
        self.send_transcription(text, timestamp, is_preview=True)

    def _send_loop(self):
        """Background thread for sending transcriptions."""
        while self.is_running:
            try:
                # Get transcription from queue (with shorter timeout for responsiveness)
                try:
                    trans_data = self.send_queue.get(timeout=0.1)
                except queue.Empty:
                    continue

                # Send to server in parallel using thread pool
                # This allows multiple requests to be in-flight simultaneously
                self.executor.submit(self._send_to_server, trans_data)

            except Exception as e:
                print(f"Error in server sync send loop: {e}")
                self.error_count += 1
                self.last_error = str(e)

    def _send_to_server(self, trans_data: dict):
        """
        Send a transcription to the server (PHP or Node.js).

        Args:
            trans_data: Dictionary with 'text' and 'timestamp'
        """
        import time
        send_start = time.time()

        try:
            # Debug: Calculate queue delay
            if 'queue_time' in trans_data:
                queue_delay = (send_start - trans_data['queue_time']) * 1000
                print(f"[Server Sync] Queue delay: {queue_delay:.0f}ms")

            # Prepare payload
            payload = {
                'room': self.room,
                'passphrase': self.passphrase,
                'user_name': self.user_name,
                'text': trans_data['text'],
                'timestamp': trans_data['timestamp'],
                'is_preview': trans_data.get('is_preview', False)
            }

            # Add font info if user has a custom font configured
            if self.font_family:
                payload['font_family'] = self.font_family
                payload['font_type'] = self.font_type  # "websafe", "google", or "custom"
                print(f"[Server Sync] Sending with font: {self.font_family} ({self.font_type})")
            else:
                print(f"[Server Sync] No font configured (font_source={self.font_source})")

            # Send to Node.js server
            request_start = time.time()
            response = requests.post(
                self.url,
                json=payload,
                timeout=2.0  # Reduced timeout for faster failure detection
            )

            request_time = (time.time() - request_start) * 1000
            print(f"[Server Sync] HTTP request: {request_time:.0f}ms, Status: {response.status_code}")

            # Check response
            if response.status_code == 200:
                self.sent_count += 1
                self.last_error = None
            else:
                error_msg = f"Server returned {response.status_code}"
                try:
                    error_data = response.json()
                    if 'error' in error_data:
                        error_msg = error_data['error']
                except:
                    pass

                print(f"Server sync error: {error_msg}")
                self.error_count += 1
                self.last_error = error_msg

        except requests.exceptions.Timeout:
            print("Server sync timeout")
            self.error_count += 1
            self.last_error = "Request timeout"

        except requests.exceptions.ConnectionError:
            print("Server sync connection error")
            self.error_count += 1
            self.last_error = "Connection error"

        except Exception as e:
            print(f"Server sync error: {e}")
            self.error_count += 1
            self.last_error = str(e)

    def get_stats(self) -> dict:
        """Get sync statistics."""
        return {
            'sent': self.sent_count,
            'errors': self.error_count,
            'last_error': self.last_error,
            'queue_size': self.send_queue.qsize()
        }

    def is_healthy(self) -> bool:
        """Check if sync is working (no recent errors)."""
        # Consider healthy if less than 10% error rate
        total = self.sent_count + self.error_count
        if total == 0:
            return True
        return (self.error_count / total) < 0.1