"""GitHub ingestion for Opus Orchestrator.

Fetches content from GitHub repositories for use as source material.
"""

import os
import base64
import re
from typing import Any, Optional

import requests
# Note: dotenv loading removed - set GITHUB_TOKEN environment variable directly


class GitHubIngestor:
    """Fetch and parse content from GitHub repositories."""
    
    def __init__(self, token: Optional[str] = None):
        self.token = token or os.environ.get("GITHUB_TOKEN")
        
        # Token is optional - only required for private repos
        # Public repos can be accessed without authentication
        if self.token:
            self.headers = {
                "Authorization": f"token {self.token}",
                "Accept": "application/vnd.github.v3+json",
            }
        else:
            # No token - use unauthenticated requests (rate limited)
            self.headers = {
                "Accept": "application/vnd.github.v3+json",
            }
            print("⚠️  No GitHub token provided. Using unauthenticated requests (rate limited).")
        
        self.base_url = "https://api.github.com"
    
    def get_contents(self, repo: str, path: str = "") -> list[dict]:
        """Get contents of a directory or file.
        
        Args:
            repo: "owner/repo" format
            path: directory path (default: root)
            
        Returns:
            List of content items
        """
        url = f"{self.base_url}/repos/{repo}/contents/{path}"
        
        response = requests.get(url, headers=self.headers)
        response.raise_for_status()
        
        return response.json()
    
    def get_file_content(self, repo: str, path: str) -> str:
        """Get content of a single file.
        
        Args:
            repo: "owner/repo" format
            path: file path
            
        Returns:
            Decoded file content
        """
        url = f"{self.base_url}/repos/{repo}/contents/{path}"
        
        response = requests.get(url, headers=self.headers)
        response.raise_for_status()
        
        data = response.json()
        
        # Decode base64 content
        if data.get("encoding") == "base64":
            content = base64.b64decode(data["content"]).decode("utf-8")
            return content
        
        return data.get("content", "")
    
    def get_all_files(
        self,
        repo: str,
        extensions: Optional[list[str]] = None,
        exclude_dirs: Optional[list[str]] = None,
        include_all: bool = True,
    ) -> dict[str, str]:
        """Get all files from a repository - INCLUDING SOURCE CODE.
        
        The AI witnesses EVERYTHING and transforms it into documentation.
        Don't filter what the AI can see - let it decide what's relevant.
        
        Args:
            repo: "owner/repo" format
            extensions: File extensions to include (None = ALL files!)
            exclude_dirs: Directories to exclude (build artifacts, etc.)
            include_all: If True, include ALL files (default True!)
            
        Returns:
            Dictionary mapping file paths to content
        """
        # Default: include ALL files - the AI will witness everything!
        if include_all:
            extensions = None  # No extension filter
            exclude_dirs = exclude_dirs or [".git", "node_modules", "__pycache__", ".github", "dist", "build", "*.egg-info"]
        else:
            extensions = extensions or [".md", ".txt", ".text", ".notes", ".draft", ".rst"]
            exclude_dirs = exclude_dirs or [".git", "node_modules", "__pycache__", ".github"]
        
        files = {}
        
        def walk_directory(path: str = ""):
            contents = self.get_contents(repo, path)
            
            if isinstance(contents, dict):
                # Single file
                if contents.get("type") == "file":
                    content_path = contents["path"]
                    if self._should_include(content_path, extensions, exclude_dirs, include_all):
                        files[content_path] = self.get_file_content(repo, content_path)
                return
            
            for item in contents:
                item_path = item.get("path", "")
                item_type = item.get("type")
                
                if item_type == "dir":
                    # Check if excluded
                    if not any(excl in item_path for excl in exclude_dirs):
                        walk_directory(item_path)
                elif item_type == "file":
                    if self._should_include(item_path, extensions, exclude_dirs, include_all):
                        files[item_path] = self.get_file_content(repo, item_path)
        
        walk_directory()
        return files
    
    def _should_include(
        self,
        path: str,
        extensions: Optional[list[str]],
        exclude_dirs: list[str],
        include_all: bool = True,
    ) -> bool:
        """Check if file should be included.
        
        Args:
            path: File path to check
            extensions: List of extensions (None if include_all=True)
            exclude_dirs: Directories to exclude
            include_all: Include ALL files (ignore extensions)
        """
        # Exclude directories
        for excl in exclude_dirs:
            if excl in path:
                return False
        
        # If include_all, include everything
        if include_all:
            return True
        
        # Otherwise check extensions
        if extensions:
            return any(path.endswith(ext) for ext in extensions)
        
        return True
    
    def extract_text_from_files(self, files: dict[str, str]) -> str:
        """Combine all file contents into a single text blob.
        
        Args:
            files: Dictionary of filename -> content
            
        Returns:
            Combined text
        """
        combined = []
        
        for filename, content in sorted(files.items()):
            combined.append(f"=== {filename} ===\n")
            combined.append(content)
            combined.append("\n\n")
        
        return "".join(combined)
    
    def ingest_repo(
        self,
        repo: str,
        include_readme: bool = True,
    ) -> dict[str, Any]:
        """Ingest a complete repository.
        
        Args:
            repo: "owner/repo" format
            include_readme: Include README.md files
            
        Returns:
            Dictionary with files, combined_text, and metadata
        """
        # Get all markdown and text files
        files = self.get_all_files(repo)
        
        # Optionally exclude README
        if not include_readme:
            files = {k: v for k, v in files.items() if "README" not in k}
        
        # Combine into single text
        combined = self.extract_text_from_files(files)
        
        return {
            "repo": repo,
            "files": files,
            "combined_text": combined,
            "file_count": len(files),
            "total_chars": len(combined),
        }


def create_github_ingestor(token: Optional[str] = None) -> GitHubIngestor:
    """Factory function to create GitHub ingestor."""
    return GitHubIngestor(token=token)