"""
Social media publishing abstraction layer.

Supports Facebook, Instagram, YouTube, and TikTok via their respective APIs.
All HTTP calls use httpx (sync).
"""

from __future__ import annotations

import time
from abc import ABC, abstractmethod

import httpx

TIMEOUT = 120.0
UPLOAD_TIMEOUT = 300.0


class SocialPublisher(ABC):
    """Abstract base class for social media publishers."""

    @abstractmethod
    def publish_text(self, text: str, **kwargs) -> str:
        """Publish a text-only post.

        Returns:
            External post ID from the platform.
        """
        ...

    @abstractmethod
    def publish_image(self, text: str, image_url: str, **kwargs) -> str:
        """Publish an image post with caption.

        Returns:
            External post ID from the platform.
        """
        ...

    @abstractmethod
    def publish_video(self, text: str, video_path: str, **kwargs) -> str:
        """Publish a video post with caption.

        Returns:
            External post ID from the platform.
        """
        ...

    @abstractmethod
    def get_comments(self, post_id: str) -> list[dict]:
        """Get comments on a post.

        Returns:
            List of comment dicts with at least 'id', 'text', 'author' keys.
        """
        ...

    @abstractmethod
    def reply_to_comment(self, comment_id: str, text: str) -> bool:
        """Reply to a specific comment.

        Returns:
            True if reply was successful, False otherwise.
        """
        ...


class FacebookPublisher(SocialPublisher):
    """Facebook Page publishing via Graph API.

    Required API setup:
    - Create a Facebook App at https://developers.facebook.com
    - Request 'pages_manage_posts', 'pages_read_engagement' permissions
    - Get a Page Access Token (long-lived recommended)
    - The page_id is the Facebook Page ID (numeric)
    """

    GRAPH_API_BASE = "https://graph.facebook.com/v18.0"

    def __init__(self, access_token: str, page_id: str):
        self.access_token = access_token
        self.page_id = page_id

    def _request(
        self,
        method: str,
        endpoint: str,
        params: dict | None = None,
        data: dict | None = None,
        files: dict | None = None,
        timeout: float = TIMEOUT,
    ) -> dict:
        """Make a request to the Facebook Graph API."""
        url = f"{self.GRAPH_API_BASE}{endpoint}"
        if params is None:
            params = {}
        params["access_token"] = self.access_token

        try:
            with httpx.Client(timeout=timeout) as client:
                if method == "GET":
                    response = client.get(url, params=params)
                elif files:
                    response = client.post(url, params=params, data=data, files=files)
                else:
                    response = client.post(url, params=params, json=data)
                response.raise_for_status()
                return response.json()
        except httpx.HTTPStatusError as e:
            raise RuntimeError(
                f"Facebook API error {e.response.status_code}: {e.response.text}"
            ) from e
        except httpx.RequestError as e:
            raise RuntimeError(f"Facebook API request failed: {e}") from e

    def publish_text(self, text: str, **kwargs) -> str:
        data = {"message": text}
        result = self._request("POST", f"/{self.page_id}/feed", data=data)
        return result.get("id", "")

    def publish_image(self, text: str, image_url: str, **kwargs) -> str:
        data = {
            "message": text,
            "url": image_url,
        }
        result = self._request("POST", f"/{self.page_id}/photos", data=data)
        return result.get("id", "")

    def publish_video(self, text: str, video_path: str, **kwargs) -> str:
        with open(video_path, "rb") as video_file:
            files = {"source": ("video.mp4", video_file, "video/mp4")}
            form_data = {"description": text}
            result = self._request(
                "POST",
                f"/{self.page_id}/videos",
                data=form_data,
                files=files,
                timeout=UPLOAD_TIMEOUT,
            )
        return result.get("id", "")

    def get_comments(self, post_id: str) -> list[dict]:
        result = self._request("GET", f"/{post_id}/comments")
        comments = []
        for item in result.get("data", []):
            comments.append({
                "id": item.get("id", ""),
                "text": item.get("message", ""),
                "author": item.get("from", {}).get("name", "Unknown"),
                "created_at": item.get("created_time", ""),
            })
        return comments

    def reply_to_comment(self, comment_id: str, text: str) -> bool:
        try:
            self._request("POST", f"/{comment_id}/comments", data={"message": text})
            return True
        except RuntimeError:
            return False


class InstagramPublisher(SocialPublisher):
    """Instagram publishing via Instagram Graph API (Business/Creator accounts).

    Required API setup:
    - Facebook App with Instagram Graph API enabled
    - Instagram Business or Creator account linked to a Facebook Page
    - Permissions: 'instagram_basic', 'instagram_content_publish'
    - ig_user_id is the Instagram Business Account ID (from Facebook Graph API)
    - Note: Text-only posts are not supported by Instagram API
    """

    GRAPH_API_BASE = "https://graph.facebook.com/v18.0"

    def __init__(self, access_token: str, ig_user_id: str):
        self.access_token = access_token
        self.ig_user_id = ig_user_id

    def _request(
        self,
        method: str,
        endpoint: str,
        params: dict | None = None,
        data: dict | None = None,
        timeout: float = TIMEOUT,
    ) -> dict:
        """Make a request to the Instagram Graph API."""
        url = f"{self.GRAPH_API_BASE}{endpoint}"
        if params is None:
            params = {}
        params["access_token"] = self.access_token

        try:
            with httpx.Client(timeout=timeout) as client:
                if method == "GET":
                    response = client.get(url, params=params)
                else:
                    response = client.post(url, params=params, json=data)
                response.raise_for_status()
                return response.json()
        except httpx.HTTPStatusError as e:
            raise RuntimeError(
                f"Instagram API error {e.response.status_code}: {e.response.text}"
            ) from e
        except httpx.RequestError as e:
            raise RuntimeError(f"Instagram API request failed: {e}") from e

    def publish_text(self, text: str, **kwargs) -> str:
        """Instagram does not support text-only posts.

        Raises RuntimeError. Use publish_image or publish_video instead.
        """
        raise RuntimeError(
            "Instagram does not support text-only posts. "
            "Use publish_image() or publish_video() instead."
        )

    def publish_image(self, text: str, image_url: str, **kwargs) -> str:
        # Step 1: Create media container
        container_data = {
            "image_url": image_url,
            "caption": text,
        }
        container = self._request(
            "POST", f"/{self.ig_user_id}/media", data=container_data
        )
        container_id = container.get("id", "")

        if not container_id:
            raise RuntimeError("Failed to create Instagram media container")

        # Step 2: Publish the container
        publish_data = {"creation_id": container_id}
        result = self._request(
            "POST", f"/{self.ig_user_id}/media_publish", data=publish_data
        )
        return result.get("id", "")

    def publish_video(self, text: str, video_path: str, **kwargs) -> str:
        """Publish a video as a Reel on Instagram.

        Note: video_path should be a publicly accessible URL for Instagram API.
        For local files, upload to a hosting service first and pass the URL.
        """
        video_url = kwargs.get("video_url", video_path)

        # Step 1: Create media container for Reel
        container_data = {
            "media_type": "REELS",
            "video_url": video_url,
            "caption": text,
        }
        container = self._request(
            "POST", f"/{self.ig_user_id}/media", data=container_data
        )
        container_id = container.get("id", "")

        if not container_id:
            raise RuntimeError("Failed to create Instagram video container")

        # Step 2: Wait for video processing (poll status)
        for _ in range(60):
            status = self._request(
                "GET",
                f"/{container_id}",
                params={"fields": "status_code"},
            )
            status_code = status.get("status_code", "")
            if status_code == "FINISHED":
                break
            if status_code == "ERROR":
                raise RuntimeError("Instagram video processing failed")
            time.sleep(5)
        else:
            raise RuntimeError("Instagram video processing timed out")

        # Step 3: Publish
        publish_data = {"creation_id": container_id}
        result = self._request(
            "POST", f"/{self.ig_user_id}/media_publish", data=publish_data
        )
        return result.get("id", "")

    def get_comments(self, post_id: str) -> list[dict]:
        result = self._request(
            "GET",
            f"/{post_id}/comments",
            params={"fields": "id,text,username,timestamp"},
        )
        comments = []
        for item in result.get("data", []):
            comments.append({
                "id": item.get("id", ""),
                "text": item.get("text", ""),
                "author": item.get("username", "Unknown"),
                "created_at": item.get("timestamp", ""),
            })
        return comments

    def reply_to_comment(self, comment_id: str, text: str) -> bool:
        try:
            self._request(
                "POST",
                f"/{comment_id}/replies",
                data={"message": text},
            )
            return True
        except RuntimeError:
            return False


class YouTubePublisher(SocialPublisher):
    """YouTube publishing via YouTube Data API v3.

    Required API setup:
    - Google Cloud project with YouTube Data API v3 enabled
    - OAuth 2.0 credentials (access_token from OAuth flow)
    - Scopes: 'https://www.googleapis.com/auth/youtube.upload',
              'https://www.googleapis.com/auth/youtube.force-ssl'
    - Note: Uploads require OAuth, not just an API key
    """

    API_BASE = "https://www.googleapis.com"
    UPLOAD_URL = "https://www.googleapis.com/upload/youtube/v3/videos"

    def __init__(self, access_token: str):
        self.access_token = access_token

    def _headers(self) -> dict:
        return {"Authorization": f"Bearer {self.access_token}"}

    def publish_text(self, text: str, **kwargs) -> str:
        """YouTube does not support text-only posts via Data API.

        Consider using YouTube Community Posts API if available.
        """
        raise RuntimeError(
            "YouTube does not support text-only posts via the Data API. "
            "Use publish_video() instead."
        )

    def publish_image(self, text: str, image_url: str, **kwargs) -> str:
        """YouTube does not support image-only posts via Data API."""
        raise RuntimeError(
            "YouTube does not support image posts via the Data API. "
            "Use publish_video() instead."
        )

    def publish_video(self, text: str, video_path: str, **kwargs) -> str:
        """Upload a video to YouTube using resumable upload.

        Args:
            text: Video description.
            video_path: Path to the video file.
            **kwargs: Additional options:
                - title (str): Video title (default: first 100 chars of text)
                - tags (list[str]): Video tags
                - privacy (str): 'public', 'unlisted', or 'private' (default: 'public')
                - category_id (str): YouTube category ID (default: '22' for People & Blogs)
        """
        title = kwargs.get("title", text[:100])
        tags = kwargs.get("tags", [])
        privacy = kwargs.get("privacy", "public")
        category_id = kwargs.get("category_id", "22")

        # Step 1: Initialize resumable upload
        metadata = {
            "snippet": {
                "title": title,
                "description": text,
                "tags": tags,
                "categoryId": category_id,
            },
            "status": {
                "privacyStatus": privacy,
            },
        }

        headers = self._headers()
        headers["Content-Type"] = "application/json"

        try:
            with httpx.Client(timeout=UPLOAD_TIMEOUT) as client:
                # Init resumable upload
                init_response = client.post(
                    self.UPLOAD_URL,
                    params={
                        "uploadType": "resumable",
                        "part": "snippet,status",
                    },
                    headers=headers,
                    json=metadata,
                )
                init_response.raise_for_status()

                upload_url = init_response.headers.get("location")
                if not upload_url:
                    raise RuntimeError(
                        "YouTube API did not return a resumable upload URL"
                    )

                # Step 2: Upload the video file
                with open(video_path, "rb") as video_file:
                    video_data = video_file.read()

                upload_headers = {
                    "Authorization": f"Bearer {self.access_token}",
                    "Content-Type": "video/*",
                    "Content-Length": str(len(video_data)),
                }

                upload_response = client.put(
                    upload_url,
                    headers=upload_headers,
                    content=video_data,
                )
                upload_response.raise_for_status()
                result = upload_response.json()
                return result.get("id", "")

        except httpx.HTTPStatusError as e:
            raise RuntimeError(
                f"YouTube API error {e.response.status_code}: {e.response.text}"
            ) from e
        except httpx.RequestError as e:
            raise RuntimeError(f"YouTube API request failed: {e}") from e

    def get_comments(self, post_id: str) -> list[dict]:
        """Get comment threads for a video.

        Args:
            post_id: YouTube video ID.
        """
        url = f"{self.API_BASE}/youtube/v3/commentThreads"
        params = {
            "part": "snippet",
            "videoId": post_id,
            "maxResults": 100,
            "order": "time",
        }

        try:
            with httpx.Client(timeout=TIMEOUT) as client:
                response = client.get(url, headers=self._headers(), params=params)
                response.raise_for_status()
                data = response.json()
        except httpx.HTTPStatusError as e:
            raise RuntimeError(
                f"YouTube API error {e.response.status_code}: {e.response.text}"
            ) from e
        except httpx.RequestError as e:
            raise RuntimeError(f"YouTube API request failed: {e}") from e

        comments = []
        for item in data.get("items", []):
            snippet = item.get("snippet", {}).get("topLevelComment", {}).get("snippet", {})
            comments.append({
                "id": item.get("snippet", {}).get("topLevelComment", {}).get("id", ""),
                "text": snippet.get("textDisplay", ""),
                "author": snippet.get("authorDisplayName", "Unknown"),
                "created_at": snippet.get("publishedAt", ""),
            })
        return comments

    def reply_to_comment(self, comment_id: str, text: str) -> bool:
        """Reply to a YouTube comment.

        Args:
            comment_id: The parent comment ID to reply to.
            text: Reply text.
        """
        url = f"{self.API_BASE}/youtube/v3/comments"
        params = {"part": "snippet"}
        payload = {
            "snippet": {
                "parentId": comment_id,
                "textOriginal": text,
            }
        }

        try:
            with httpx.Client(timeout=TIMEOUT) as client:
                response = client.post(
                    url, headers=self._headers(), params=params, json=payload
                )
                response.raise_for_status()
                return True
        except (httpx.HTTPStatusError, httpx.RequestError):
            return False


class TikTokPublisher(SocialPublisher):
    """TikTok publishing via Content Posting API.

    Required API setup:
    - Register app at https://developers.tiktok.com
    - Apply for 'Content Posting API' access
    - OAuth 2.0 flow to get access_token
    - Scopes: 'video.publish', 'video.upload'
    - Note: TikTok API access requires app review and approval
    - Text-only and image posts are not supported via API
    """

    API_BASE = "https://open.tiktokapis.com/v2"

    def __init__(self, access_token: str):
        self.access_token = access_token

    def _headers(self) -> dict:
        return {
            "Authorization": f"Bearer {self.access_token}",
            "Content-Type": "application/json",
        }

    def publish_text(self, text: str, **kwargs) -> str:
        """TikTok does not support text-only posts via API."""
        raise RuntimeError(
            "TikTok does not support text-only posts via the Content Posting API. "
            "Use publish_video() instead."
        )

    def publish_image(self, text: str, image_url: str, **kwargs) -> str:
        """TikTok image posting is limited. Use publish_video instead."""
        raise RuntimeError(
            "TikTok image posting is not widely supported via the API. "
            "Use publish_video() instead."
        )

    def publish_video(self, text: str, video_path: str, **kwargs) -> str:
        """Publish a video to TikTok using the Content Posting API.

        Args:
            text: Video caption/description.
            video_path: Path to the video file.
            **kwargs: Additional options:
                - privacy_level (str): 'PUBLIC_TO_EVERYONE', 'MUTUAL_FOLLOW_FRIENDS',
                  'FOLLOWER_OF_CREATOR', 'SELF_ONLY' (default: 'PUBLIC_TO_EVERYONE')
                - disable_comment (bool): Disable comments (default: False)
                - disable_duet (bool): Disable duet (default: False)
                - disable_stitch (bool): Disable stitch (default: False)
        """
        privacy_level = kwargs.get("privacy_level", "PUBLIC_TO_EVERYONE")
        disable_comment = kwargs.get("disable_comment", False)
        disable_duet = kwargs.get("disable_duet", False)
        disable_stitch = kwargs.get("disable_stitch", False)

        # Get file size for chunk upload
        import os

        file_size = os.path.getsize(video_path)

        # Step 1: Initialize video upload
        init_url = f"{self.API_BASE}/post/publish/video/init/"
        init_payload = {
            "post_info": {
                "title": text[:150],  # TikTok title limit
                "privacy_level": privacy_level,
                "disable_comment": disable_comment,
                "disable_duet": disable_duet,
                "disable_stitch": disable_stitch,
            },
            "source_info": {
                "source": "FILE_UPLOAD",
                "video_size": file_size,
                "chunk_size": file_size,  # Single chunk upload
                "total_chunk_count": 1,
            },
        }

        try:
            with httpx.Client(timeout=UPLOAD_TIMEOUT) as client:
                init_response = client.post(
                    init_url, headers=self._headers(), json=init_payload
                )
                init_response.raise_for_status()
                init_data = init_response.json()

                publish_id = init_data.get("data", {}).get("publish_id", "")
                upload_url = init_data.get("data", {}).get("upload_url", "")

                if not upload_url:
                    raise RuntimeError(
                        f"TikTok API did not return upload URL: {init_data}"
                    )

                # Step 2: Upload the video file
                with open(video_path, "rb") as video_file:
                    video_data = video_file.read()

                upload_headers = {
                    "Content-Type": "video/mp4",
                    "Content-Range": f"bytes 0-{file_size - 1}/{file_size}",
                }

                upload_response = client.put(
                    upload_url,
                    headers=upload_headers,
                    content=video_data,
                )
                upload_response.raise_for_status()

                return publish_id

        except httpx.HTTPStatusError as e:
            raise RuntimeError(
                f"TikTok API error {e.response.status_code}: {e.response.text}"
            ) from e
        except httpx.RequestError as e:
            raise RuntimeError(f"TikTok API request failed: {e}") from e

    def get_comments(self, post_id: str) -> list[dict]:
        """Get comments on a TikTok video.

        Note: Requires 'video.list' scope and comment read access.
        """
        url = f"{self.API_BASE}/comment/list/"
        payload = {
            "video_id": post_id,
            "max_count": 50,
        }

        try:
            with httpx.Client(timeout=TIMEOUT) as client:
                response = client.post(url, headers=self._headers(), json=payload)
                response.raise_for_status()
                data = response.json()
        except httpx.HTTPStatusError as e:
            raise RuntimeError(
                f"TikTok API error {e.response.status_code}: {e.response.text}"
            ) from e
        except httpx.RequestError as e:
            raise RuntimeError(f"TikTok API request failed: {e}") from e

        comments = []
        for item in data.get("data", {}).get("comments", []):
            comments.append({
                "id": item.get("id", ""),
                "text": item.get("text", ""),
                "author": item.get("user", {}).get("display_name", "Unknown"),
                "created_at": str(item.get("create_time", "")),
            })
        return comments

    def reply_to_comment(self, comment_id: str, text: str) -> bool:
        """Reply to a TikTok comment.

        Note: Comment reply functionality may be limited depending on API access level.
        """
        url = f"{self.API_BASE}/comment/reply/"
        payload = {
            "comment_id": comment_id,
            "text": text,
        }

        try:
            with httpx.Client(timeout=TIMEOUT) as client:
                response = client.post(url, headers=self._headers(), json=payload)
                response.raise_for_status()
                return True
        except (httpx.HTTPStatusError, httpx.RequestError):
            return False


def get_publisher(
    platform: str, access_token: str, **kwargs
) -> SocialPublisher:
    """Factory function to get a social media publisher instance.

    Args:
        platform: One of 'facebook', 'instagram', 'youtube', 'tiktok'.
        access_token: OAuth access token for the platform.
        **kwargs: Additional platform-specific arguments:
            - facebook: page_id (str) - required
            - instagram: ig_user_id (str) - required

    Returns:
        A SocialPublisher instance.

    Raises:
        ValueError: If platform is not supported or required kwargs are missing.
    """
    platform_lower = platform.lower()

    if platform_lower == "facebook":
        page_id = kwargs.get("page_id")
        if not page_id:
            raise ValueError("FacebookPublisher requires 'page_id' parameter")
        return FacebookPublisher(access_token=access_token, page_id=page_id)

    elif platform_lower == "instagram":
        ig_user_id = kwargs.get("ig_user_id")
        if not ig_user_id:
            raise ValueError("InstagramPublisher requires 'ig_user_id' parameter")
        return InstagramPublisher(access_token=access_token, ig_user_id=ig_user_id)

    elif platform_lower == "youtube":
        return YouTubePublisher(access_token=access_token)

    elif platform_lower == "tiktok":
        return TikTokPublisher(access_token=access_token)

    else:
        supported = "facebook, instagram, youtube, tiktok"
        raise ValueError(
            f"Unknown platform '{platform}'. Supported: {supported}"
        )