#!/usr/bin/env python3
"""
Comprehensive demo of the EbookReader functionality.

This script demonstrates all features of the pyWebLayout EbookReader:
- Loading EPUB files
- Page navigation (forward/backward)
- Position saving/loading
- Chapter navigation
- Font size and spacing adjustments
- Getting book and position information

Usage:
    python ereader_demo.py path/to/book.epub
"""

import sys
import os
from pathlib import Path

from pyweblayout_ereader import EbookReader


def print_separator():
    """Print a visual separator."""
    print("\n" + "="*70 + "\n")


def demo_basic_navigation(reader: EbookReader):
    """Demonstrate basic page navigation."""
    print("DEMO: Basic Navigation")
    print_separator()
    
    # Get current page
    print("Getting first page...")
    page = reader.get_current_page()
    if page:
        print(f"✓ Current page rendered: {page.size}")
        reader.render_to_file("demo_page_001.png")
        print("  Saved to: demo_page_001.png")
    
    # Navigate forward
    print("\nNavigating to next page...")
    page = reader.next_page()
    if page:
        print(f"✓ Next page rendered: {page.size}")
        reader.render_to_file("demo_page_002.png")
        print("  Saved to: demo_page_002.png")
    
    # Navigate backward
    print("\nNavigating to previous page...")
    page = reader.previous_page()
    if page:
        print(f"✓ Previous page rendered: {page.size}")
    
    print_separator()


def demo_position_management(reader: EbookReader):
    """Demonstrate position save/load functionality."""
    print("DEMO: Position Management")
    print_separator()
    
    # Navigate a few pages forward
    print("Navigating forward 3 pages...")
    for i in range(3):
        reader.next_page()
    
    # Save position
    print("Saving current position as 'demo_bookmark'...")
    success = reader.save_position("demo_bookmark")
    if success:
        print("✓ Position saved successfully")
    
    # Get position info
    pos_info = reader.get_position_info()
    print(f"\nCurrent position info:")
    print(f"  Chapter: {pos_info.get('chapter', {}).get('title', 'N/A')}")
    print(f"  Block index: {pos_info['position']['block_index']}")
    print(f"  Word index: {pos_info['position']['word_index']}")
    print(f"  Progress: {pos_info['progress']*100:.1f}%")
    
    # Navigate away
    print("\nNavigating forward 5 more pages...")
    for i in range(5):
        reader.next_page()
    
    # Load saved position
    print("Loading saved position 'demo_bookmark'...")
    page = reader.load_position("demo_bookmark")
    if page:
        print("✓ Position restored successfully")
        reader.render_to_file("demo_restored_position.png")
        print("  Saved to: demo_restored_position.png")
    
    # List all saved positions
    positions = reader.list_saved_positions()
    print(f"\nAll saved positions: {positions}")
    
    print_separator()


def demo_chapter_navigation(reader: EbookReader):
    """Demonstrate chapter navigation."""
    print("DEMO: Chapter Navigation")
    print_separator()
    
    # Get all chapters
    chapters = reader.get_chapters()
    print(f"Found {len(chapters)} chapters:")
    for title, idx in chapters[:5]:  # Show first 5
        print(f"  [{idx}] {title}")
    
    if len(chapters) > 5:
        print(f"  ... and {len(chapters) - 5} more")
    
    # Jump to a chapter by index
    if len(chapters) > 1:
        print(f"\nJumping to chapter 1...")
        page = reader.jump_to_chapter(1)
        if page:
            print("✓ Jumped to chapter successfully")
            reader.render_to_file("demo_chapter_1.png")
            print("  Saved to: demo_chapter_1.png")
            
            # Get current chapter info
            chapter_info = reader.get_current_chapter_info()
            if chapter_info:
                print(f"  Current chapter: {chapter_info['title']}")
    
    # Jump to a chapter by title (if we have chapters)
    if len(chapters) > 0:
        first_chapter_title = chapters[0][0]
        print(f"\nJumping to chapter by title: '{first_chapter_title}'...")
        page = reader.jump_to_chapter(first_chapter_title)
        if page:
            print("✓ Jumped to chapter by title successfully")
    
    print_separator()


def demo_font_size_adjustment(reader: EbookReader):
    """Demonstrate font size adjustments."""
    print("DEMO: Font Size Adjustment")
    print_separator()
    
    # Save current page for comparison
    print("Rendering page at normal font size (1.0x)...")
    page = reader.get_current_page()
    if page:
        reader.render_to_file("demo_font_normal.png")
        print("✓ Saved to: demo_font_normal.png")
    
    # Increase font size
    print("\nIncreasing font size...")
    page = reader.increase_font_size()
    if page:
        print(f"✓ Font size increased to {reader.get_font_size():.1f}x")
        reader.render_to_file("demo_font_larger.png")
        print("  Saved to: demo_font_larger.png")
    
    # Increase again
    print("\nIncreasing font size again...")
    page = reader.increase_font_size()
    if page:
        print(f"✓ Font size increased to {reader.get_font_size():.1f}x")
        reader.render_to_file("demo_font_largest.png")
        print("  Saved to: demo_font_largest.png")
    
    # Decrease font size
    print("\nDecreasing font size...")
    page = reader.decrease_font_size()
    if page:
        print(f"✓ Font size decreased to {reader.get_font_size():.1f}x")
    
    # Set specific font size
    print("\nResetting to normal font size (1.0x)...")
    page = reader.set_font_size(1.0)
    if page:
        print("✓ Font size reset to 1.0x")
    
    print_separator()


def demo_spacing_adjustment(reader: EbookReader):
    """Demonstrate line and block spacing adjustments."""
    print("DEMO: Spacing Adjustment")
    print_separator()
    
    # Save current page
    print("Rendering page with default spacing...")
    page = reader.get_current_page()
    if page:
        reader.render_to_file("demo_spacing_default.png")
        print("✓ Saved to: demo_spacing_default.png")
    
    # Increase line spacing
    print("\nIncreasing line spacing to 10px...")
    page = reader.set_line_spacing(10)
    if page:
        print("✓ Line spacing increased")
        reader.render_to_file("demo_spacing_lines_10.png")
        print("  Saved to: demo_spacing_lines_10.png")
    
    # Increase inter-block spacing
    print("\nIncreasing inter-block spacing to 25px...")
    page = reader.set_inter_block_spacing(25)
    if page:
        print("✓ Inter-block spacing increased")
        reader.render_to_file("demo_spacing_blocks_25.png")
        print("  Saved to: demo_spacing_blocks_25.png")
    
    # Reset to defaults
    print("\nResetting spacing to defaults (line: 5px, block: 15px)...")
    reader.set_line_spacing(5)
    page = reader.set_inter_block_spacing(15)
    if page:
        print("✓ Spacing reset to defaults")
    
    print_separator()


def demo_book_information(reader: EbookReader):
    """Demonstrate getting book information."""
    print("DEMO: Book Information")
    print_separator()
    
    # Get book info
    book_info = reader.get_book_info()
    print("Book Information:")
    print(f"  Title: {book_info['title']}")
    print(f"  Author: {book_info['author']}")
    print(f"  Document ID: {book_info['document_id']}")
    print(f"  Total blocks: {book_info['total_blocks']}")
    print(f"  Total chapters: {book_info['total_chapters']}")
    print(f"  Page size: {book_info['page_size']}")
    print(f"  Font scale: {book_info['font_scale']}")
    
    # Get reading progress
    progress = reader.get_reading_progress()
    print(f"\nReading Progress: {progress*100:.1f}%")
    
    # Get detailed position info
    pos_info = reader.get_position_info()
    print("\nDetailed Position:")
    print(f"  Chapter index: {pos_info['position']['chapter_index']}")
    print(f"  Block index: {pos_info['position']['block_index']}")
    print(f"  Word index: {pos_info['position']['word_index']}")
    
    chapter = pos_info.get('chapter', {})
    if chapter.get('title'):
        print(f"  Current chapter: {chapter['title']}")
    
    print_separator()


def main():
    """Main function to run all demos."""
    if len(sys.argv) < 2:
        print("Usage: python ereader_demo.py path/to/book.epub")
        print("\nExample EPUBs to try:")
        print("  - tests/data/test.epub")
        print("  - tests/data/test2.epub")
        sys.exit(1)
    
    epub_path = sys.argv[1]
    
    if not os.path.exists(epub_path):
        print(f"Error: File not found: {epub_path}")
        sys.exit(1)
    
    print("="*70)
    print(" EbookReader Demo - pyWebLayout")
    print("="*70)
    print(f"\nLoading EPUB: {epub_path}")
    
    # Create reader with context manager
    with EbookReader(page_size=(800, 1000)) as reader:
        # Load the EPUB
        if not reader.load_epub(epub_path):
            print("Error: Failed to load EPUB file")
            sys.exit(1)
        
        print("✓ EPUB loaded successfully")
        
        # Run all demos
        try:
            demo_basic_navigation(reader)
            demo_position_management(reader)
            demo_chapter_navigation(reader)
            demo_font_size_adjustment(reader)
            demo_spacing_adjustment(reader)
            demo_book_information(reader)
            
            print("\n" + "="*70)
            print(" Demo Complete!")
            print("="*70)
            print("\nGenerated demo images:")
            demo_files = [
                "demo_page_001.png",
                "demo_page_002.png",
                "demo_restored_position.png",
                "demo_chapter_1.png",
                "demo_font_normal.png",
                "demo_font_larger.png",
                "demo_font_largest.png",
                "demo_spacing_default.png",
                "demo_spacing_lines_10.png",
                "demo_spacing_blocks_25.png"
            ]
            
            for filename in demo_files:
                if os.path.exists(filename):
                    print(f"  ✓ {filename}")
            
            print("\nAll features demonstrated successfully!")
            
        except Exception as e:
            print(f"\nError during demo: {e}")
            import traceback
            traceback.print_exc()
            sys.exit(1)


if __name__ == "__main__":
    main()