"""
Script generation module using Google Gemini Pro

This module generates natural Japanese narration scripts based on:
- Extracted PDF data
- Video transcription
- Template constraints
"""

import os
from typing import Dict, Any, List, Optional


class ScriptGenerator:
    """Generate narration scripts using Gemini Pro"""
    
    def __init__(self, api_key: Optional[str] = None):
        self.api_key = api_key or os.getenv("GEMINI_API_KEY")
        if not self.api_key:
            raise ValueError("GEMINI_API_KEY not found in environment")
    
    def generate(
        self, 
        pdf_data: Dict[str, Any], 
        video_data: Optional[Dict[str, Any]] = None,
        style: str = "friendly"
    ) -> Dict[str, Any]:
        """
        Generate narration script
        
        Args:
            pdf_data: Structured data from PDF extraction
            video_data: Optional video transcription data
            style: Narration style ('friendly', 'professional', 'casual')
            
        Returns:
            Dictionary containing:
            - segments: List of narration segments
            - total_duration: Estimated total duration in seconds
            - sync_points: Recommended chart/video sync points
        """
        # TODO: Implement script generation
        # 1. Build prompt with PDF data and constraints
        # 2. Call Gemini Pro API
        # 3. Parse and structure the response
        # 4. Estimate timing for each segment
        
        raise NotImplementedError("Script generation not yet implemented")
    
    def _build_prompt(self, pdf_data: Dict, style: str) -> str:
        """Build the prompt for Gemini Pro"""
        # TODO: Implement prompt engineering
        # Should include:
        # - PDF data summary
        # - Style guidelines (natural Japanese, friendly tone)
        # - Output format requirements (JSON with segments)
        # - Length constraints (target 3-5 minutes)
        
        return ""


def generate_script(
    pdf_data: Dict[str, Any], 
    video_data: Optional[Dict[str, Any]] = None
) -> Dict[str, Any]:
    """Convenience function for script generation"""
    generator = ScriptGenerator()
    return generator.generate(pdf_data, video_data)