#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Xiaohongshu Blogger Historical Posts Fetcher

Features:
1. Fetch blogger's historical posts (posts command)
   - Input Xiaohongshu author ID
   - Call API to get blogger's homepage info and historical posts
   - Support pagination
   - Output to author directory's historical posts folder
   - Filename is post ID with .json extension
   - Auto fetch post details when body_text > threshold (default: 90 chars)
   - Update original post file's body_text with complete version from detail API

2. Fetch single post detail (detail command)
   - Input Xiaohongshu note ID
   - Call API to get post detail
   - Save to specified output file

Usage:
  # Fetch historical posts (with auto body_text update)
  python fetch.py posts <account_id> [-o output_dir] [-m max_pages] [-d delay]

  # Fetch historical posts without auto detail fetching
  python fetch.py posts <account_id> --no-auto-detail

  # Fetch historical posts with custom threshold (e.g., 120 chars)
  python fetch.py posts <account_id> --detail-threshold 120

  # Fetch single post detail
  python fetch.py detail <note_id> [-o output_file]
"""

import requests
import json
import os
import time
from typing import Optional, Dict, List


class XHSBloggerFetcher:
    """Xiaohongshu Blogger Historical Posts Fetcher"""

    API_URL = "http://47.84.182.56:8001/tools/call/get_xhs_blogger_historical_posts"
    DETAIL_API_URL = "http://47.84.182.56:8001/tools/call/get_xhs_detail_by_note_id"

    def __init__(self, account_id: str, output_dir: Optional[str] = None,
                 auto_fetch_detail: bool = True, detail_threshold: int = 90):
        """
        Initialize fetcher

        Args:
            account_id: Xiaohongshu blogger's ID
            output_dir: Output directory path, defaults to current dir + account_name
            auto_fetch_detail: Whether to auto fetch detail for posts with body_text > threshold
            detail_threshold: Minimum character count in body_text to trigger detail fetch (default: 90)
        """
        self.account_id = account_id
        self.account_name = None  # Will be set from first post's channel_account_name
        self.output_dir = output_dir
        self.posts_dir = None
        self.first_post_saved = False  # Track if first post has been copied
        self.auto_fetch_detail = auto_fetch_detail
        self.detail_threshold = detail_threshold
        # Statistics
        self.detail_fetch_count = 0  # Successfully fetched and updated details
        self.detail_skip_count = 0   # Skipped due to low character count
        self.detail_error_count = 0  # Failed to fetch details

    def fetch_posts(self, cursor: Optional[str] = None) -> Dict:
        """
        Fetch blogger's historical posts

        Args:
            cursor: Pagination cursor, not passed for first request

        Returns:
            API response data
        """
        payload = {
            "account_id": self.account_id
        }

        if cursor:
            payload["cursor"] = cursor

        try:
            response = requests.post(
                self.API_URL,
                json=payload,
                headers={"Content-Type": "application/json"},
                timeout=30
            )
            response.raise_for_status()
            return response.json()
        except requests.exceptions.RequestException as e:
            print(f"API request failed: {e}")
            return {}

    def fetch_post_detail(self, note_id: str) -> Dict:
        """
        Fetch single post detail by note ID

        Args:
            note_id: Xiaohongshu note ID

        Returns:
            API response data containing post details
        """
        payload = {
            "note_id": note_id
        }

        try:
            response = requests.post(
                self.DETAIL_API_URL,
                json=payload,
                headers={"Content-Type": "application/json"},
                timeout=30
            )
            response.raise_for_status()
            return response.json()
        except requests.exceptions.RequestException as e:
            print(f"API request failed: {e}")
            return {}

    def _convert_post_format(self, post: Dict) -> Dict:
        """
        Convert API post format to standard format

        Args:
            post: Original post data from API

        Returns:
            Converted post data in standard format
        """
        from datetime import datetime

        # Extract image URLs from image_url_list
        images = []
        for img in post.get("image_url_list", []):
            if isinstance(img, dict):
                images.append(img.get("image_url", ""))
            elif isinstance(img, str):
                images.append(img)

        # Extract video URL from video_url_list
        video_list = post.get("video_url_list", [])
        video = ""
        if video_list:
            if isinstance(video_list[0], dict):
                video = video_list[0].get("video_url", "")
            elif isinstance(video_list[0], str):
                video = video_list[0]

        # Convert timestamp to datetime string
        publish_timestamp = post.get("publish_timestamp", 0)
        publish_time = ""
        if publish_timestamp:
            try:
                dt = datetime.fromtimestamp(publish_timestamp / 1000)
                publish_time = dt.strftime("%Y-%m-%d %H:%M:%S")
            except:
                publish_time = ""

        # Build standard format
        converted = {
            "channel_content_id": post.get("channel_content_id"),
            "link": post.get("content_link", ""),
            "comment_count": post.get("comment_count", 0),
            "images": images,
            "like_count": post.get("like_count", 0),
            "body_text": post.get("body_text", ""),
            "title": post.get("title", ""),
            "collect_count": post.get("collect_count", 0),
            "channel_account_id": post.get("channel_account_id", ""),
            "channel_account_name": post.get("channel_account_name", ""),
            "content_type": post.get("content_type", "note"),
            "video": video,
            "publish_timestamp": publish_timestamp,
            "publish_time": publish_time
        }

        return converted

    def _initialize_directories(self, account_name: str):
        """
        Initialize output directories using account name

        Args:
            account_name: Account name from first post
        """
        if self.posts_dir is not None:
            return  # Already initialized

        self.account_name = account_name

        # Use provided output_dir or default to current dir + account_name
        if self.output_dir is None:
            self.output_dir = os.path.join(os.getcwd(), account_name)

        self.posts_dir = os.path.join(self.output_dir, "作者历史帖子")

        # Ensure output directory exists
        os.makedirs(self.posts_dir, exist_ok=True)

    def _count_body_text_chars(self, body_text: str) -> int:
        """
        Count characters in body_text

        Args:
            body_text: The post body text

        Returns:
            Total number of characters (including all whitespace, emoji, etc.)
        """
        if not body_text:
            return 0
        # Return the total length of the string
        return len(body_text)

    def save_post(self, post: Dict, is_first_post: bool = False) -> bool:
        """
        Save single post to JSON file

        Args:
            post: Post data
            is_first_post: Whether this is the first post (will be copied to parent directory)

        Returns:
            Whether save was successful
        """
        # Initialize directories on first post using account name
        if self.posts_dir is None:
            account_name = post.get("channel_account_name")
            if not account_name:
                print(f"Warning: Post data missing channel_account_name field, using account_id instead")
                account_name = self.account_id
            self._initialize_directories(account_name)

        # Get post ID as filename
        post_id = post.get("channel_content_id")
        if not post_id:
            print(f"Warning: Post data missing channel_content_id field, skipping")
            return False

        file_path = os.path.join(self.posts_dir, f"{post_id}.json")

        try:
            # Convert to standard format before saving
            converted_post = self._convert_post_format(post)

            with open(file_path, 'w', encoding='utf-8') as f:
                json.dump(converted_post, f, ensure_ascii=False, indent=2)
            print(f"✓ Saved post: {post_id}.json")

            # If this is the first post, copy it to parent directory as "待解构帖子.json"
            if is_first_post and not self.first_post_saved:
                target_path = os.path.join(self.output_dir, "待解构帖子.json")
                with open(target_path, 'w', encoding='utf-8') as f:
                    json.dump(converted_post, f, ensure_ascii=False, indent=2)
                print(f"✓ Copied first post to: 待解构帖子.json")
                self.first_post_saved = True

            # Auto fetch post detail if body_text exceeds threshold
            if self.auto_fetch_detail:
                body_text = converted_post.get("body_text", "")
                char_count = self._count_body_text_chars(body_text)

                if char_count > self.detail_threshold:
                    print(f"  → Body text has {char_count} chars (> {self.detail_threshold}), fetching detail...")

                    # Fetch detail
                    response_data = self.fetch_post_detail(post_id)

                    if response_data and response_data.get('success'):
                        try:
                            # Parse the result field (it's a JSON string containing a list)
                            result_str = response_data.get('result', '[]')
                            result_list = json.loads(result_str)

                            # The result is a list with one item, which contains 'data' field
                            if isinstance(result_list, list) and len(result_list) > 0:
                                detail_data = result_list[0].get('data', {})

                                if detail_data and 'body_text' in detail_data:
                                    # Update the original post file with detailed body_text
                                    detail_body_text = detail_data.get('body_text', '')
                                    if detail_body_text and detail_body_text != body_text:
                                        converted_post['body_text'] = detail_body_text
                                        # Re-save the post file with updated body_text
                                        with open(file_path, 'w', encoding='utf-8') as f:
                                            json.dump(converted_post, f, ensure_ascii=False, indent=2)
                                        print(f"  ✓ Updated body_text with complete version from detail API")
                                    else:
                                        print(f"  → Body text already complete, no update needed")

                                    self.detail_fetch_count += 1
                                else:
                                    print(f"  ✗ No valid data in detail response")
                                    self.detail_error_count += 1
                            else:
                                print(f"  ✗ Unexpected detail response format")
                                self.detail_error_count += 1
                        except Exception as e:
                            print(f"  ✗ Failed to parse/update detail: {e}")
                            self.detail_error_count += 1
                    else:
                        print(f"  ✗ Failed to fetch detail")
                        self.detail_error_count += 1
                else:
                    print(f"  → Body text has {char_count} chars (<= {self.detail_threshold}), skipping detail fetch")
                    self.detail_skip_count += 1

            return True
        except Exception as e:
            print(f"✗ Failed to save post {post_id}: {e}")
            return False

    def fetch_all_posts(self, max_pages: Optional[int] = None, delay: float = 1.0) -> int:
        """
        Fetch all historical posts (with pagination support)

        Args:
            max_pages: Maximum pages to fetch, None means fetch all
            delay: Delay between requests in seconds

        Returns:
            Number of successfully saved posts
        """
        cursor = None
        page = 0
        total_saved = 0

        print(f"Starting to fetch historical posts for blogger: {self.account_id}")
        print("-" * 60)

        while True:
            page += 1
            print(f"\nPage {page}:")

            # Fetch data
            response_data = self.fetch_posts(cursor)

            if not response_data:
                print("Failed to fetch data, stopping")
                break

            # Extract posts list (adjust based on actual API response structure)
            posts = self._extract_posts(response_data)

            if not posts:
                print("No more posts, finished")
                break

            # Save posts
            print(f"Got {len(posts)} posts on this page")
            for idx, post in enumerate(posts):
                # Mark the first post overall (page 1, first post)
                is_first = (page == 1 and idx == 0)
                if self.save_post(post, is_first_post=is_first):
                    total_saved += 1
                    # Print output directory info after first post is saved
                    if is_first:
                        print(f"Output directory: {self.posts_dir}")

            # Check if there's a next page
            cursor = self._get_next_cursor(response_data)
            if not cursor:
                print("\nAll posts fetched")
                break

            # Check if max pages limit reached
            if max_pages and page >= max_pages:
                print(f"\nReached max pages limit ({max_pages} pages)")
                break

            # Delay to avoid too frequent requests
            if delay > 0:
                time.sleep(delay)

        print("-" * 60)
        print(f"✓ Done! Saved {total_saved} posts to: {self.posts_dir}")

        # Print detail fetch statistics if auto_fetch_detail is enabled
        if self.auto_fetch_detail:
            print(f"\nBody Text Update Statistics:")
            print(f"  ✓ Successfully updated: {self.detail_fetch_count}")
            print(f"  → Skipped (text <= {self.detail_threshold} chars): {self.detail_skip_count}")
            print(f"  ✗ Failed: {self.detail_error_count}")

        return total_saved

    def _extract_posts(self, response_data: Dict) -> List[Dict]:
        """
        Extract posts list from API response

        Args:
            response_data: API response data

        Returns:
            List of posts
        """
        try:
            # Check if API call was successful
            if not response_data.get('success'):
                print(f"API call failed: {response_data}")
                return []

            # Parse the result field (it's a JSON string)
            result_str = response_data.get('result', '{}')
            result = json.loads(result_str)

            # Check response code
            if result.get('code') != 0:
                print(f"API returned error code: {result.get('code')}, message: {result.get('msg')}")
                return []

            # Extract posts from result.data.data
            data = result.get('data', {})
            posts = data.get('data', [])

            return posts if isinstance(posts, list) else []

        except json.JSONDecodeError as e:
            print(f"Failed to parse result JSON: {e}")
            return []
        except Exception as e:
            print(f"Error extracting posts: {e}")
            return []

    def _get_next_cursor(self, response_data: Dict) -> Optional[str]:
        """
        Extract next page cursor from API response

        Args:
            response_data: API response data

        Returns:
            Next page cursor, or None if no more pages
        """
        try:
            # Check if API call was successful
            if not response_data.get('success'):
                return None

            # Parse the result field (it's a JSON string)
            result_str = response_data.get('result', '{}')
            result = json.loads(result_str)

            # Extract cursor from result.data.next_cursor and check has_more
            data = result.get('data', {})
            has_more = data.get('has_more', False)
            next_cursor = data.get('next_cursor')

            # Only return cursor if there are more pages
            if has_more and next_cursor:
                return str(next_cursor)

            return None

        except Exception as e:
            print(f"Error extracting next cursor: {e}")
            return None

    def fetch_and_save_post_detail(self, note_id: str, output_path: Optional[str] = None) -> bool:
        """
        Fetch post detail by note_id and save to file

        Args:
            note_id: Xiaohongshu note ID
            output_path: Optional output file path, defaults to {note_id}_detail.json

        Returns:
            Whether fetch and save was successful
        """
        print(f"Fetching post detail for note_id: {note_id}")
        print("-" * 60)

        # Fetch post detail
        response_data = self.fetch_post_detail(note_id)

        if not response_data:
            print("✗ Failed to fetch post detail")
            return False

        try:
            # Check if API call was successful
            if not response_data.get('success'):
                print(f"✗ API call failed: {response_data}")
                return False

            # Parse the result field (it's a JSON string)
            result_str = response_data.get('result', '{}')
            result = json.loads(result_str)

            # Check response code
            if result.get('code') != 0:
                print(f"✗ API returned error code: {result.get('code')}, message: {result.get('msg')}")
                return False

            # Extract post data from result.data
            post_data = result.get('data', {})

            if not post_data:
                print("✗ No post data in response")
                return False

            # Determine output path
            if output_path is None:
                output_path = f"{note_id}_detail.json"

            # Save to file
            with open(output_path, 'w', encoding='utf-8') as f:
                json.dump(post_data, f, ensure_ascii=False, indent=2)

            print(f"✓ Post detail saved to: {output_path}")
            print("-" * 60)
            return True

        except json.JSONDecodeError as e:
            print(f"✗ Failed to parse result JSON: {e}")
            return False
        except Exception as e:
            print(f"✗ Error saving post detail: {e}")
            return False


def main():
    """Main function"""
    import argparse

    parser = argparse.ArgumentParser(description='Fetch Xiaohongshu blogger historical posts or single post detail')

    # Create subparsers for different commands
    subparsers = parser.add_subparsers(dest='command', help='Command to execute')

    # Subparser for fetching historical posts
    posts_parser = subparsers.add_parser('posts', help='Fetch blogger historical posts')
    posts_parser.add_argument('account_id', help='Xiaohongshu blogger ID')
    posts_parser.add_argument('-o', '--output', help='Output directory path (default: current dir + account_name)')
    posts_parser.add_argument('-m', '--max-pages', type=int, help='Maximum pages to fetch (default: fetch all)')
    posts_parser.add_argument('-d', '--delay', type=float, default=1.0, help='Request delay in seconds (default: 1.0)')
    posts_parser.add_argument('--no-auto-detail', action='store_true', help='Disable auto fetching post details')
    posts_parser.add_argument('--detail-threshold', type=int, default=90,
                             help='Minimum character count in body_text to trigger detail fetch (default: 90)')

    # Subparser for fetching single post detail
    detail_parser = subparsers.add_parser('detail', help='Fetch single post detail by note_id')
    detail_parser.add_argument('note_id', help='Xiaohongshu note ID')
    detail_parser.add_argument('-o', '--output', help='Output file path (default: {note_id}_detail.json)')

    args = parser.parse_args()

    # If no command specified, show help
    if not args.command:
        parser.print_help()
        return

    # Execute corresponding command
    if args.command == 'posts':
        # Create fetcher and execute
        auto_fetch_detail = not args.no_auto_detail  # Invert the flag
        fetcher = XHSBloggerFetcher(
            args.account_id,
            args.output,
            auto_fetch_detail=auto_fetch_detail,
            detail_threshold=args.detail_threshold
        )
        fetcher.fetch_all_posts(max_pages=args.max_pages, delay=args.delay)

    elif args.command == 'detail':
        # Create a minimal fetcher instance (account_id not needed for detail fetching)
        fetcher = XHSBloggerFetcher(account_id='')
        fetcher.fetch_and_save_post_detail(args.note_id, args.output)


if __name__ == '__main__':
    main()