import logging
import copy
import re
from datetime import datetime
from typing import Union, Dict, Any, List, Optional
from pyrogram.types import Message
from pyrogram.enums import MessageMediaType
from config import get_settings
import os
import json

Config = get_settings()

logger = logging.getLogger(__name__)
logger.setLevel(logging.INFO)

if not logger.handlers:
    handler = logging.StreamHandler()
    handler.setFormatter(logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s'))
    logger.addHandler(handler)


#tests
#http://127.0.0.1:8000/post/html/DragorWW_space/114 — video
#http://127.0.0.1:8000/post/html/DragorWW_space/20 - many photos
#http://127.0.0.1:8000/post/html/DragorWW_space/58 - photos+video
#http://127.0.0.1:8000/post/html/DragorWW_space/44 - poll
#http://127.0.0.1:8000/post/html/DragorWW_space/46 - photo
#http://127.0.0.1:8000/post/html/DragorWW_space/49, http://127.0.0.1:8000/post/html/DragorWW_space/63  — webpage
#http://127.0.0.1:8000/post/html/deckru/826 - animation
#http://127.0.0.1:8000/post/html/DragorWW_space/61 — links
#http://127.0.0.1:8000/post/html/theyforcedme/3577 - video note
#http://127.0.0.1:8000/post/html/theyforcedme/3572 - audio
#http://127.0.0.1:8000/post/html/theyforcedme/3558 - audio-note
#http://127.0.0.1:8000/html/vvzvlad_lytdybr/426 - sticker
#http://127.0.0.1:8000/html/wrkshprn/634, http://127.0.0.1:8000/html/ni404head/1278 — links without <a>
#http://127.0.0.1:8000/html/ru2ch_ban/26586 - large video
#http://127.0.0.1:8000/html/smallpharm/4828 - forwarded from channel
#http://127.0.0.1:8000/html/vvzvlad_lytdybr/659 - forwarded from user
#http://127.0.0.1:8000/html/ufjqk/1070 - reply to
#http://127.0.0.1:8000/html/tetstststststststffd/4 - forwarded from channel without name


class PostParser:
    def __init__(self, client):
        self.client = client

    def _debug_message(self, message: Message) -> Message:
        if Config["debug"]:   
            debug_message = copy.deepcopy(message)
            debug_message.sender_chat = None
            debug_message.caption_entities = None
            debug_message.reactions = None
            debug_message.entities = None
            print(debug_message)
        return

    async def get_post(self, channel: str, post_id: int, output_type: str = 'json') -> Union[str, Dict[Any, Any]]:
        try:
            message = await self.client.get_messages(channel, post_id)

            self._debug_message(message)

            if not message:
                logger.error(f"post_not_found: channel {channel}, post_id {post_id}")
                return None
            
            if output_type == 'html':
                return self._format_html(message)
            elif output_type == 'json':
                return self._format_json(message)
            else:
                logger.error(f"Invalid output type: {output_type}")
                return None
            
        except Exception as e:
            logger.error(f"post_parsing_error: channel {channel}, post_id {post_id}, error {str(e)}")
            raise

    def _format_json(self, message: Message, naked: bool = False) -> Dict[Any, Any]:
        html_content = self._format_html(message, naked=naked)
        result = {
            'channel': message.chat.username,
            'message_id': message.id,
            'date': datetime.timestamp(message.date),
            'text': message.text or message.caption or '',
            'html': html_content,
            'title': self._generate_title(message),
            'author': self._get_author_info(message),
            'views': message.views,
        }
        
        if message.media_group_id:
            result['media_group_id'] = message.media_group_id
        
        return result

    def _get_author_info(self, message: Message) -> str:
        if message.sender_chat:
            title = getattr(message.sender_chat, 'title', '').strip()
            username = getattr(message.sender_chat, 'username', '').strip()
            return f"{title} by @{username}" if username else title
        elif message.from_user:
            first = getattr(message.from_user, 'first_name', '').strip()
            last = getattr(message.from_user, 'last_name', '').strip()
            username = getattr(message.from_user, 'username', '').strip()
            name = ' '.join(filter(None, [first, last]))
            return f"{name} by @{username}" if username else name
        return "Unknown author"

    def _generate_title(self, message: Message) -> str:
        # Check for "channel created" service message
        if getattr(message, "channel_chat_created", False):
            return "✨ Channel created"
        text = message.text or message.caption or ''
        if not text:
            if message.media == MessageMediaType.PHOTO: return "📷 Photo"
            elif message.media == MessageMediaType.VIDEO: return "🎥 Video"
            elif message.media == MessageMediaType.ANIMATION: return "🎞 GIF"
            elif message.media == MessageMediaType.AUDIO: return "🎵 Audio"
            elif message.media == MessageMediaType.VOICE: return "🎤 Voice message"
            elif message.media == MessageMediaType.VIDEO_NOTE: return "🎥 Video message"
            elif message.media == MessageMediaType.STICKER: return "🎯 Sticker"
            elif message.media == MessageMediaType.POLL: return "📊 Poll"
            return "📷 Media post"

        # Remove URLs
        text = re.sub(r'http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\\(\\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+', '', text)
        # Remove HTML tags
        text = re.sub('<[^<]+?>', '', text)
        # Remove multiple spaces and empty lines
        text = '\n'.join(line.strip() for line in text.split('\n') if line.strip())

        # Get first non-empty line
        first_line = text.split('\n')[0] if text else ""
        
        max_length = 100
        if len(first_line) <= max_length:
            return first_line.strip()
        
        # Cut to last space
        trimmed = first_line[:max_length]
        last_space = trimmed.rfind(' ')
        if last_space > 0:
            trimmed = trimmed[:last_space]
        
        return f"{trimmed.strip()}..." if trimmed else ""

    def _format_forward_info(self, message: Message) -> Union[str, None]:
        if forward_from_chat := getattr(message, "forward_from_chat", None):
            forward_title = getattr(forward_from_chat, "title", "Unknown channel")
            forward_username = getattr(forward_from_chat, "username", None)
            if forward_username:
                forward_link = f'<a href="https://t.me/{forward_username}">{forward_title} (@{forward_username})</a>'
                return f'<div class="message-forward">Forwarded from {forward_link}</div><br>'
            return f'<div class="message-forward">Forwarded from {forward_title}</div><br>'
        
        elif forward_from := getattr(message, "forward_from", None):
            forward_name = f"{getattr(forward_from, 'first_name', '')} {getattr(forward_from, 'last_name', '')}".strip()
            forward_username = getattr(forward_from, "username", None)
            if forward_username:
                forward_link = f'<a href="https://t.me/{forward_username}">{forward_name} (@{forward_username})</a>'
                return f'<div class="message-forward">Forwarded from {forward_link}</div><br>'
            return f'<div class="message-forward">Forwarded from {forward_name}</div><br>'
        
        return None

    def _format_reply_info(self, message: Message) -> Union[str, None]:
        if reply_to := getattr(message, "reply_to_message", None):
            reply_text = reply_to.text or reply_to.caption or ''
            if len(reply_text) > 100:
                reply_text = reply_text[:100] + '...'
            
            channel_username = getattr(reply_to.chat, "username", None)
            if channel_username:
                reply_link = f'<a href="https://t.me/{channel_username}/{reply_to.id}">#{reply_to.id}</a>'
                return f'<div class="message-reply">Reply to {reply_link}: {reply_text}</div><br>'
            return f'<div class="message-reply">Reply to #{reply_to.id}: {reply_text}</div><br>'
        
        return None

    def _format_html(self, message: Message, naked: bool = False) -> str:
        html_content = []
        
        # Add forwarded from or reply info if present
        if forward_html := self._format_forward_info(message):
            html_content.append(forward_html)
        elif reply_html := self._format_reply_info(message):
            html_content.append(reply_html)

        # Check for "channel created" service message
        if getattr(message, "channel_chat_created", False):
            service_html = '<div class="message-service">Channel created</div>'
            if not naked:
                return self._wrap_html([service_html])
            return service_html

        text = message.text.html if message.text else message.caption.html if message.caption else ''
        text = text.replace('\n', '<br>')
        
        # Add hyperlinks to raw URLs
        text = self._add_hyperlinks_to_raw_urls(text)
        
        # Save media file_ids
        self._save_media_file_ids(message)
                
        if poll := getattr(message, "poll", None): # Poll formatting
            if poll_html := self._format_poll(poll):
                html_content.append(poll_html)
                
        base_url = Config['pyrogram_bridge_url']
        if message.media and message.media != "MessageMediaType.POLL":
            file_unique_id = self._get_file_unique_id(message)
            if file_unique_id is None:
                logger.debug(f"File unique id not found for message {message.id}")
            elif file_unique_id:
                url = f"{base_url}/media/{message.chat.username}/{message.id}/{file_unique_id}"
                logger.debug(f"Collected media file: {message.chat.username}/{message.id}/{file_unique_id}")
                html_content.append(f'<div class="message-media">')
                if message.media in [MessageMediaType.PHOTO, MessageMediaType.DOCUMENT]:
                    html_content.append(f'<img src="{url}" style="max-width:600px; max-height:600px; object-fit:contain;">')
                elif message.media == MessageMediaType.VIDEO:
                    html_content.append(f'<video controls src="{url}" style="max-width:600px; max-height:600px;"></video>')
                elif message.media == MessageMediaType.ANIMATION:
                    html_content.append(f'<video controls src="{url}" style="max-width:600px; max-height:600px;"></video>')
                elif message.media == MessageMediaType.VIDEO_NOTE:
                    html_content.append(f'<video controls src="{url}" style="max-width:600px; max-height:600px;"></video>')
                elif message.media == MessageMediaType.AUDIO:
                    mime_type = getattr(message.audio, 'mime_type', 'audio/mpeg')
                    html_content.append(f'<audio controls style="width:100%; max-width:400px;"><source src="{url}" type="{mime_type}"></audio>')
                elif message.media == MessageMediaType.VOICE:
                    mime_type = getattr(message.voice, 'mime_type', 'audio/ogg')
                    html_content.append(f'<audio controls style="width:100%; max-width:400px;"><source src="{url}" type="{mime_type}"></audio>')
                elif message.media == MessageMediaType.STICKER:
                    emoji = getattr(message.sticker, 'emoji', '')
                    html_content.append(f'<img src="{url}" alt="Sticker {emoji}" style="max-width:300px; max-height:300px; object-fit:contain;">')
                html_content.append('</div>')

        
        if webpage := getattr(message, "web_page", None): # Web page preview
            if webpage_html := self._format_webpage(webpage, message):
                html_content.append(webpage_html)

        if text: # Message text
            html_content.append(f'<div class="message-text">{text}</div>')

        if not naked:
            if reactions_views_html := self._reactions_views_links(message): # Add reactions, views and links
                html_content.append(reactions_views_html)
        
        if not naked:
            html = self._wrap_html(html_content)
        else:
            html = '\n'.join(html_content)
            
        return html

    def _add_hyperlinks_to_raw_urls(self, text: str) -> str:
        try:
            # Find all existing <a> tags
            a_tags = re.finditer(r'<a[^>]*>.*?</a>', text)
            # Store their positions
            excluded_ranges = [(m.start(), m.end()) for m in a_tags]
            
            # Find all URLs that are not already in HTML tags
            result = text
            offset = 0
            
            for match in re.finditer(r'https?://[^\s<>"\']+', text):
                start, end = match.span()
                
                # Check if URL is inside an <a> tag
                is_in_tag = any(tag_start <= start and end <= tag_end for tag_start, tag_end in excluded_ranges)
                if not is_in_tag:
                    url = match.group()
                    replacement = f'<a href="{url}" target="_blank">{url}</a>'
                    
                    # Apply replacement considering offset
                    result = result[:start + offset] + replacement + result[end + offset:]
                    offset += len(replacement) - (end - start)
            
            return result
            
        except Exception as e:
            logger.error(f"url_processing_error: error {str(e)}")
            return text

    def _format_webpage(self, webpage, message) -> Union[str, None]:
        base_url = Config['pyrogram_bridge_url']
        try:
            if photo := getattr(webpage, "photo", None):
                logger.debug(f"Processing webpage with photo: message_id={message.id}, photo={photo}")
                if file_unique_id := getattr(photo, "file_unique_id", None):
                    url = f"{base_url}/media/{message.chat.username}/{message.id}/{file_unique_id}"
                    logger.debug(f"Generated media URL: {url}")
                    return (
                        f'<div style="margin:5px;">'
                        f'<a href="{webpage.url}" target="_blank">'
                        f'<img src="{url}" style="max-width:600px; max-height:600px; object-fit:contain;"></a>'
                        f'</div>'
                    )
                else:
                    logger.error(f"webpage_photo_error: no file_unique_id found for photo in message {message.id}")
            return None
        except Exception as e:
            logger.error(f"webpage_parsing_error: url {getattr(webpage, 'url', 'unknown')}, error {str(e)}")
            return None

    def _wrap_html(self, html_content: list) -> str:
        struct  = [
            '<!DOCTYPE html>', '<html>',
            '<head>', '<meta charset="UTF-8">', '</head>',
            '<body>', *html_content, '</body>',
            '</html>'
        ]
        html_content = '\n'.join(struct)
        return html_content

    def _reactions_views_links(self, message: Message) -> Union[str, None]:
        try:
            html_parts = []
            html_parts.append("<br>")
            
            if reactions := getattr(message, "reactions", None): #add reactions
                reactions_html = ''
                for reaction in reactions.reactions:
                    reactions_html += f'<span class="reaction">{reaction.emoji} {reaction.count}</span> '
                html_parts.append(reactions_html)

            if views := getattr(message, "views", None): #add views
                views_html = f'<span class="views">(Views: {views})</span>'
                html_parts.append(views_html)

            if message.chat.username: #add links to telegram and web
                tg_link = f'<br><a href="tg://resolve?domain={message.chat.username}&post={message.id}">Open in Telegram</a>'
                html_parts.append(tg_link)
                tg_web_link = f'<br><a href="https://t.me/{message.chat.username}/{message.id}">Open in Web</a>'
                html_parts.append(tg_web_link)

            html = ' '.join(html_parts) if html_parts else None
            return html
            
        except Exception as e:
            logger.error(f"reactions_views_parsing_error: {str(e)}")
            return None

    def _format_poll(self, poll) -> str:
        try:
            poll_text = f"📊 Poll: {poll.question}\n"
            if hasattr(poll, "options") and poll.options:
                for i, option in enumerate(poll.options, 1):
                    poll_text += f"{i}. {getattr(option, 'text', '')}\n"
            poll_text += "\n→ Vote in Telegram 🔗\n"
            return f'<div class="message-poll">{poll_text.replace(chr(10), "<br>")}</div>'
        except Exception as e:
            logger.error(f"poll_parsing_error: {str(e)}")
            return '<div class="message-poll">[Error displaying poll]</div>'

    def _get_file_unique_id(self, message: Message) -> Union[str, None]:
        try:
            media_mapping = {
                MessageMediaType.PHOTO: lambda m: m.photo.file_unique_id,
                MessageMediaType.VIDEO: lambda m: m.video.file_unique_id,
                MessageMediaType.DOCUMENT: lambda m: m.document.file_unique_id,
                MessageMediaType.AUDIO: lambda m: m.audio.file_unique_id,
                MessageMediaType.VOICE: lambda m: m.voice.file_unique_id,
                MessageMediaType.VIDEO_NOTE: lambda m: m.video_note.file_unique_id,
                MessageMediaType.ANIMATION: lambda m: m.animation.file_unique_id,
                MessageMediaType.STICKER: lambda m: m.sticker.file_unique_id,
                MessageMediaType.WEB_PAGE: lambda m: m.web_page.photo.file_unique_id if m.web_page and m.web_page.photo else None
            }
            
            if message.media in media_mapping:
                return media_mapping[message.media](message)
            
            return None
            
        except Exception as e:
            logger.error(f"file_id_extraction_error: media_type {message.media}, error {str(e)}")
            return None

    async def get_recent_posts(self, channel: str, limit: int = 20) -> List[Dict[Any, Any]]:
        """
        Get recent posts from channel
        """
        try:
            messages = []
            async for message in self.client.get_chat_history(channel, limit=limit):
                try:
                    post = await self.get_post(channel, message.id, output_type='json')
                    if post:
                        messages.append(post)
                except Exception as e:
                    logger.error(f"message_processing_error: channel {channel}, message_id {message.id}, error {str(e)}")
                    continue
                    
            return messages
            
        except Exception as e:
            logger.error(f"recent_posts_error: channel {channel}, error {str(e)}")
            raise 

    def format_message_for_feed(self, message: Message, naked: bool = False) -> Dict[Any, Any]:
        return self._format_json(message, naked=naked) 

    def _save_media_file_ids(self, message: Message) -> None:
        try:
            file_data = {
                'file_id': None,
            }

            channel_username = getattr(message.chat, 'username', None)
            if not channel_username:
                logger.error(f"channel_username_error: no username found for chat in message {message.id}")
                return

            if message.media:
                if message.photo:
                    file_data['file_id'] = f"{channel_username}-{message.id}-{message.photo.file_unique_id}"
                elif message.video:
                    try:
                        if message.video.file_size > 100 * 1024 * 1024:
                            logger.info(f"Large video file for message {message.id} is not cached due to size limit")
                        else:
                            file_data['file_id'] = f"{channel_username}-{message.id}-{message.video.file_unique_id}"
                    except Exception as e:
                        logger.error(f"video_file_size_error: failed to get video file size for message {message.id}: {str(e)}")
                        file_data['file_id'] = f"{channel_username}-{message.id}-{message.video.file_unique_id}"
                elif message.document:
                    file_data['file_id'] = f"{channel_username}-{message.id}-{message.document.file_unique_id}"
                elif message.audio:
                    file_data['file_id'] = f"{channel_username}-{message.id}-{message.audio.file_unique_id}"
                elif message.voice:
                    file_data['file_id'] = f"{channel_username}-{message.id}-{message.voice.file_unique_id}"
                elif message.video_note:
                    file_data['file_id'] = f"{channel_username}-{message.id}-{message.video_note.file_unique_id}"
                elif message.animation:
                    file_data['file_id'] = f"{channel_username}-{message.id}-{message.animation.file_unique_id}"
                elif message.sticker:
                    file_data['file_id'] = f"{channel_username}-{message.id}-{message.sticker.file_unique_id}"
                elif message.web_page and message.web_page.photo:
                    file_data['file_id'] = f"{channel_username}-{message.id}-{message.web_page.photo.file_unique_id}"

            if file_data['file_id']:
                file_path = os.path.join(os.path.abspath("./data"), 'media_file_ids.json')
                try:
                    existing_data = []
                    if os.path.exists(file_path):
                        with open(file_path, 'r', encoding='utf-8') as f:
                            existing_data = json.load(f)
                    
                    # Check if file_id already exists
                    found = False
                    for item in existing_data:
                        if item['file_id'] == file_data['file_id']:
                            item['added'] = datetime.now().timestamp()
                            found = True
                            break
                    
                    # Add new entry if not found
                    if not found:
                        file_data['added'] = datetime.now().timestamp()
                        existing_data.append(file_data)
                    
                    with open(file_path, 'w', encoding='utf-8') as f:
                        json.dump(existing_data, f, ensure_ascii=False, indent=2)

                except Exception as e:
                    logger.error(f"file_id_save_error: error writing to {file_path}: {str(e)}")

        except Exception as e:
            logger.error(f"file_id_collection_error: message_id {message.id}, error {str(e)}")