#!/usr/bin/env python3
"""
Demo script for TOC overlay feature.

This script demonstrates the complete TOC overlay workflow:
1. Display reading page
2. Swipe up from bottom to open TOC overlay
3. Display TOC overlay with chapter list
4. Tap on a chapter to navigate
5. Close overlay and show new page

Generates a GIF showing all these interactions.
"""

from pathlib import Path
from dreader import EbookReader, TouchEvent, GestureType
from PIL import Image, ImageDraw, ImageFont
import time


def add_gesture_annotation(image: Image.Image, text: str, position: str = "top") -> Image.Image:
    """
    Add a text annotation to an image showing what gesture is being performed.

    Args:
        image: Base image
        text: Annotation text
        position: "top" or "bottom"

    Returns:
        Image with annotation
    """
    # Create a copy
    annotated = image.copy()
    draw = ImageDraw.Draw(annotated)

    # Try to use a nice font, fall back to default
    try:
        font = ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf", 24)
    except:
        font = ImageFont.load_default()

    # Calculate text position
    bbox = draw.textbbox((0, 0), text, font=font)
    text_width = bbox[2] - bbox[0]
    text_height = bbox[3] - bbox[1]

    x = (image.width - text_width) // 2
    if position == "top":
        y = 20
    else:
        y = image.height - text_height - 20

    # Draw background rectangle
    padding = 10
    draw.rectangle(
        [x - padding, y - padding, x + text_width + padding, y + text_height + padding],
        fill=(0, 0, 0, 200)
    )

    # Draw text
    draw.text((x, y), text, fill=(255, 255, 255), font=font)

    return annotated


def add_swipe_arrow(image: Image.Image, start_y: int, end_y: int) -> Image.Image:
    """
    Add a visual swipe arrow to show gesture direction.

    Args:
        image: Base image
        start_y: Starting Y position
        end_y: Ending Y position

    Returns:
        Image with arrow overlay
    """
    annotated = image.copy()
    draw = ImageDraw.Draw(annotated)

    # Draw arrow in center of screen
    x = image.width // 2

    # Draw line
    draw.line([(x, start_y), (x, end_y)], fill=(255, 100, 100), width=5)

    # Draw arrowhead
    arrow_size = 20
    if end_y < start_y:  # Upward arrow
        draw.polygon([
            (x, end_y),
            (x - arrow_size, end_y + arrow_size),
            (x + arrow_size, end_y + arrow_size)
        ], fill=(255, 100, 100))
    else:  # Downward arrow
        draw.polygon([
            (x, end_y),
            (x - arrow_size, end_y - arrow_size),
            (x + arrow_size, end_y - arrow_size)
        ], fill=(255, 100, 100))

    return annotated


def add_tap_indicator(image: Image.Image, x: int, y: int, label: str = "") -> Image.Image:
    """
    Add a visual tap indicator to show where user tapped.

    Args:
        image: Base image
        x, y: Tap coordinates
        label: Optional label for the tap

    Returns:
        Image with tap indicator
    """
    annotated = image.copy()
    draw = ImageDraw.Draw(annotated)

    # Draw circle at tap location
    radius = 30
    draw.ellipse(
        [x - radius, y - radius, x + radius, y + radius],
        outline=(255, 100, 100),
        width=5
    )

    # Draw crosshair
    draw.line([(x - radius - 10, y), (x + radius + 10, y)], fill=(255, 100, 100), width=3)
    draw.line([(x, y - radius - 10), (x, y + radius + 10)], fill=(255, 100, 100), width=3)

    # Add label if provided
    if label:
        try:
            font = ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf", 18)
        except:
            font = ImageFont.load_default()

        bbox = draw.textbbox((0, 0), label, font=font)
        text_width = bbox[2] - bbox[0]

        # Position label above tap point
        label_x = x - text_width // 2
        label_y = y - radius - 40

        draw.text((label_x, label_y), label, fill=(255, 100, 100), font=font)

    return annotated


def main():
    """Generate TOC overlay demo GIF"""
    print("=== TOC Overlay Demo ===")
    print()

    # Find a test EPUB
    epub_dir = Path(__file__).parent.parent / 'tests' / 'data' / 'library-epub'
    epubs = list(epub_dir.glob('*.epub'))

    if not epubs:
        print("Error: No test EPUB files found!")
        print(f"Looked in: {epub_dir}")
        return

    epub_path = epubs[0]
    print(f"Using book: {epub_path.name}")

    # Create reader
    reader = EbookReader(page_size=(800, 1200))

    # Load book
    print("Loading book...")
    success = reader.load_epub(str(epub_path))

    if not success:
        print("Error: Failed to load EPUB!")
        return

    print(f"Loaded: {reader.book_title} by {reader.book_author}")
    print(f"Chapters: {len(reader.get_chapters())}")
    print()

    # Prepare frames for GIF
    frames = []
    frame_duration = []  # Duration in milliseconds for each frame

    # Frame 1: Initial reading page
    print("Frame 1: Initial reading page...")
    page1 = reader.get_current_page()
    annotated1 = add_gesture_annotation(page1, f"Reading: {reader.book_title}", "top")
    frames.append(annotated1)
    frame_duration.append(2000)  # 2 seconds

    # Frame 2: Show swipe up gesture
    print("Frame 2: Swipe up gesture...")
    swipe_visual = add_swipe_arrow(page1, 1100, 900)
    annotated2 = add_gesture_annotation(swipe_visual, "Swipe up from bottom", "bottom")
    frames.append(annotated2)
    frame_duration.append(1000)  # 1 second

    # Frame 3: TOC overlay appears
    print("Frame 3: TOC overlay opens...")
    event_swipe_up = TouchEvent(gesture=GestureType.SWIPE_UP, x=400, y=1100)
    response = reader.handle_touch(event_swipe_up)
    print(f"  Response: {response.action}")

    # Get the overlay image by calling open_toc_overlay again
    # (handle_touch already opened it, but we need the image)
    overlay_image = reader.open_toc_overlay()
    annotated3 = add_gesture_annotation(overlay_image, "Table of Contents", "top")
    frames.append(annotated3)
    frame_duration.append(3000)  # 3 seconds to read

    # Frame 4: Show tap on chapter III (index 6)
    print("Frame 4: Tap on chapter III...")
    chapters = reader.get_chapters()
    if len(chapters) >= 7:
        # Calculate tap position for chapter III (7th in list, index 6)
        # Based on actual measurements from pyWebLayout link query:
        # Chapter 6 "III" link is clickable at screen position (200, 378)
        tap_x = 200
        tap_y = 378

        tap_visual = add_tap_indicator(overlay_image, tap_x, tap_y, "III")
        annotated4 = add_gesture_annotation(tap_visual, "Tap chapter to navigate", "bottom")
        frames.append(annotated4)
        frame_duration.append(1500)  # 1.5 seconds

        # Frame 5: Navigate to chapter III
        print(f"Frame 5: Jump to chapter III (tapping at {tap_x}, {tap_y})...")
        event_tap = TouchEvent(gesture=GestureType.TAP, x=tap_x, y=tap_y)
        response = reader.handle_touch(event_tap)
        print(f"  Response: {response.action}")

        new_page = reader.get_current_page()

        # Use the chapter title from the response data (more accurate)
        if response.action == "chapter_selected" and "chapter_title" in response.data:
            chapter_title = response.data['chapter_title']
        else:
            chapter_title = "Chapter"

        annotated5 = add_gesture_annotation(new_page, f"Navigated to: {chapter_title}", "top")
        frames.append(annotated5)
        frame_duration.append(2000)  # 2 seconds
    else:
        print("  Skipping chapter selection (not enough chapters)")

    # Frame 6: Another page for context
    print("Frame 6: Next page...")
    reader.next_page()
    page_final = reader.get_current_page()
    annotated6 = add_gesture_annotation(page_final, "Reading continues...", "top")
    frames.append(annotated6)
    frame_duration.append(2000)  # 2 seconds

    # Save as GIF
    output_path = Path(__file__).parent.parent / 'docs' / 'images' / 'toc_overlay_demo.gif'
    output_path.parent.mkdir(parents=True, exist_ok=True)

    print()
    print(f"Saving GIF with {len(frames)} frames...")
    frames[0].save(
        output_path,
        save_all=True,
        append_images=frames[1:],
        duration=frame_duration,
        loop=0,
        optimize=False
    )

    print(f"✓ GIF saved to: {output_path}")
    print(f"  Size: {output_path.stat().st_size / 1024:.1f} KB")
    print(f"  Frames: {len(frames)}")
    print(f"  Total duration: {sum(frame_duration) / 1000:.1f}s")

    # Also save individual frames for documentation
    frames_dir = output_path.parent / 'toc_overlay_frames'
    frames_dir.mkdir(exist_ok=True)

    for i, frame in enumerate(frames):
        frame_path = frames_dir / f'frame_{i+1:02d}.png'
        frame.save(frame_path)

    print(f"✓ Individual frames saved to: {frames_dir}")

    # Cleanup
    reader.close()

    print()
    print("=== Demo Complete ===")


if __name__ == '__main__':
    main()