"""
Obsidian Note Writer

Saves extracted content as markdown notes in Obsidian vault.
"""

import os
from pathlib import Path
from datetime import datetime
from typing import Optional


class ObsidianWriter:
    """Write content to Obsidian vault as markdown notes."""
    
    def __init__(self, vault_path: str):
        self.vault_path = Path(vault_path).expanduser()
        self._validate_vault()
    
    def _validate_vault(self):
        """Validate that the path is an Obsidian vault."""
        if not self.vault_path.exists():
            print(f"⚠️  Creating Obsidian vault directory: {self.vault_path}")
            self.vault_path.mkdir(parents=True, exist_ok=True)
        
        # Check if it looks like an Obsidian vault
        obsidian_config = self.vault_path / ".obsidian"
        if not obsidian_config.exists():
            print(f"⚠️  Warning: {self.vault_path} doesn't look like an Obsidian vault")
            print("   (No .obsidian directory found)")
            print("   Notes will still be saved, but you may want to set the correct vault path")
    
    def save_note(
        self, 
        content: str, 
        filename: str, 
        folder: Optional[str] = None,
        subfolder: Optional[str] = None
    ) -> Path:
        """
        Save a note to Obsidian vault.
        
        Args:
            content: Markdown content to save
            filename: Filename without .md extension
            folder: Folder in vault (default: root)
            subfolder: Subfolder within folder (optional)
        
        Returns:
            Path to saved file
        """
        # Build path
        if folder:
            note_dir = self.vault_path / folder
            if subfolder:
                note_dir = note_dir / subfolder
        else:
            note_dir = self.vault_path
        
        # Create directory if it doesn't exist
        note_dir.mkdir(parents=True, exist_ok=True)
        
        # Sanitize filename
        filename = self._sanitize_filename(filename)
        
        # Add .md extension
        filepath = note_dir / f"{filename}.md"
        
        # Handle duplicate filenames
        counter = 1
        original_filepath = filepath
        while filepath.exists():
            filepath = original_filepath.with_name(f"{filename}_{counter}.md")
            counter += 1
        
        # Write the file
        try:
            with open(filepath, 'w', encoding='utf-8') as f:
                f.write(content)
            print(f"✅ Note saved: {filepath.name}")
            return filepath
        except Exception as e:
            raise Exception(f"Failed to save note: {str(e)}")
    
    def _sanitize_filename(self, filename: str) -> str:
        """Sanitize filename for filesystem."""
        # Remove invalid characters
        invalid_chars = '<>:"/\\|?*'
        for char in invalid_chars:
            filename = filename.replace(char, '')
        
        # Replace spaces with hyphens (optional, but cleaner)
        # filename = filename.replace(' ', '-')
        
        # Limit length
        if len(filename) > 100:
            filename = filename[:100]
        
        return filename.strip()
    
    def create_daily_note(self, content: str) -> Path:
        """Create/update a daily note."""
        today = datetime.now().strftime("%Y-%m-%d")
        folder = "Daily Notes"
        return self.save_note(content, today, folder)
    
    def append_to_note(self, filename: str, content: str, folder: Optional[str] = None) -> Path:
        """Append content to an existing note."""
        if folder:
            note_dir = self.vault_path / folder
        else:
            note_dir = self.vault_path
        
        filepath = note_dir / f"{filename}.md"
        
        # If file doesn't exist, create it
        if not filepath.exists():
            return self.save_note(content, filename, folder)
        
        # Append to existing file
        try:
            with open(filepath, 'a', encoding='utf-8') as f:
                f.write("\n\n---\n\n")
                f.write(content)
            print(f"✅ Content appended to: {filepath.name}")
            return filepath
        except Exception as e:
            raise Exception(f"Failed to append to note: {str(e)}")