import logging
import json
from typing import List, Optional, Dict, Any
from db.models import Post, TargetChannel
from db.repository import Repository
from core.llm import LLMClient
from core.metrics import DUPLICATES_DETECTED_TOTAL
from core.error_logger import log_exception

logger = logging.getLogger(__name__)

CHANNEL_REWRITE_SYSTEM_PROMPT = """
You are a professional Persian Telegram copywriter and editor.
Your job is to rewrite the provided raw post specifically for the target channel: "{channel_title}".

CHANNEL PERSONALITY & TONE GUIDELINES:
{personality}

CRITICAL RULES:
1. Completely REMOVE all original channel usernames (e.g. @source_channel), sponsor tags, author watermarks, and source links.
2. Translate or rewrite into natural, highly engaging, and fluent Persian (فارسی روان، جذاب و حرفه‌ای).
3. Use appropriate emojis and clear paragraph spacing.
4. If a custom footer/tag is provided below, append it cleanly at the very end of the post:
{custom_footer}

Respond ONLY in valid JSON format:
{
  "rewritten_text": "..."
}
"""

class AIProcessor:
    def __init__(self, repo: Repository, llm: Optional[LLMClient] = None):
        self.repo = repo
        self.llm = llm or LLMClient()

    async def rewrite_for_target(self, raw_text: str, target: TargetChannel) -> str:
        """Rewrite raw text according to a specific target channel's personality and custom footer."""
        if not raw_text:
            return ""

        personality_text = target.personality.strip() if target.personality else "لحن رسمی، جذاب و روان به همراه ایموجی‌های مرتبط و پاراگراف‌بندی مرتب."
        footer_text = target.custom_footer.strip() if target.custom_footer else (f"@{target.username}" if target.username else "")

        sys_prompt = CHANNEL_REWRITE_SYSTEM_PROMPT.format(
            channel_title=target.title or "کانال تلگرام",
            personality=personality_text,
            custom_footer=footer_text
        )

        try:
            res = await self.llm.generate_json(
                prompt=f"متن اصلی پست برای بازنویسی:\n\n{raw_text}",
                system_prompt=sys_prompt,
                action_name="rewrite_target_post"
            )
            rewritten = res.get("rewritten_text")
            if rewritten:
                return rewritten.strip()
        except Exception as e:
            await log_exception("ai_processor.rewrite", e, {"target_id": target.id, "target_title": target.title})

        # Fallback if AI fails: clean basic @mentions and append footer
        fallback = raw_text
        if footer_text:
            fallback = f"{fallback}\n\n{footer_text}"
        return fallback