import json
from pathlib import Path
from typing import Dict, List, Any, Tuple
from collections import defaultdict

class HTMLGenerator:
    """Generate beautiful HTML pages from UI element JSON data."""
    
    # Confidence threshold for visual indication
    LOW_CONFIDENCE_THRESHOLD = 0.6
    
    # Column thresholds for positioning (24-column grid, 0-indexed)
    LEFT_RIGHT_THRESHOLD = 12  # Center < 12 is left, >= 12 is right
    FULL_WIDTH_SPAN = 16  # Elements spanning > 16 columns are full-width
    
    def __init__(self, json_path: str):
        """Initialize with path to JSON file."""
        self.json_path = Path(json_path)
        self.data = self._load_json()
        self.metadata = self.data.get('metadata', {})
        self.grid_system = self.metadata.get('grid_system', {})
        self.elements = self._parse_elements()
        
    def _load_json(self) -> Dict:
        """Load and parse JSON file."""
        with open(self.json_path, 'r') as f:
            return json.load(f)
    
    def _parse_elements(self) -> List[Dict]:
        """Parse and sort elements by vertical position (top to bottom), then horizontal."""
        elements = self.data.get('elements', [])
        # Sort by row position (top to bottom), then column (left to right)
        return sorted(elements, key=lambda x: (
            x['grid_position']['start_row'],
            x['grid_position']['start_col']
        ))
    
    def _is_low_confidence(self, element: Dict) -> bool:
        """Check if element has low confidence."""
        return element.get('confidence', 1.0) < self.LOW_CONFIDENCE_THRESHOLD
    
    def _calculate_element_center_col(self, element: Dict) -> float:
        """Calculate the center column position of an element."""
        grid_pos = element['grid_position']
        return (grid_pos['start_col'] + grid_pos['end_col']) / 2
    
    def _get_element_colspan(self, element: Dict) -> int:
        """Get the column span of an element."""
        return element['grid_position']['colspan']
    
    def _classify_element_position(self, element: Dict) -> str:
        """
        Classify element as 'left', 'right', or 'center' based on position.
        
        Rules:
        - CENTER: spans > 16 columns OR spans across both halves significantly
        - LEFT: center column < 12
        - RIGHT: center column >= 12
        """
        center_col = self._calculate_element_center_col(element)
        colspan = self._get_element_colspan(element)
        grid_pos = element['grid_position']
        
        # Check if it's a full-width/center element
        if colspan > self.FULL_WIDTH_SPAN:
            return 'center'
        
        # Check if it spans across both halves (crosses the 11-12 boundary significantly)
        start_col = grid_pos['start_col']
        end_col = grid_pos['end_col']
        
        # If it starts in left half and ends in right half with significant overlap
        if start_col < self.LEFT_RIGHT_THRESHOLD and end_col >= self.LEFT_RIGHT_THRESHOLD:
            # If it spans at least 4 columns on each side, consider it center
            left_span = self.LEFT_RIGHT_THRESHOLD - start_col
            right_span = end_col - self.LEFT_RIGHT_THRESHOLD
            if left_span >= 4 and right_span >= 4:
                return 'center'
        
        # Otherwise, classify by center position
        if center_col < self.LEFT_RIGHT_THRESHOLD:
            return 'left'
        else:
            return 'right'
    
    def _group_elements_by_rows(self) -> List[List[Dict]]:
        """
        Group elements into row groups based on vertical proximity.
        Elements in similar row ranges are grouped together.
        """
        if not self.elements:
            return []
        
        row_groups = []
        current_group = []
        last_end_row = -1
        
        for element in self.elements:
            start_row = element['grid_position']['start_row']
            end_row = element['grid_position']['end_row']
            
            # If this element starts within or close to the last element's range, group it
            # Gap threshold: if there's more than 2 rows gap, start new group
            if current_group and start_row > last_end_row + 2:
                row_groups.append(current_group)
                current_group = []
            
            current_group.append(element)
            last_end_row = max(last_end_row, end_row)
        
        # Add the last group
        if current_group:
            row_groups.append(current_group)
        
        return row_groups
    
    def _get_gradient_colors(self) -> tuple:
        """Return primary gradient colors."""
        return ('#667eea', '#764ba2')
    
    def _generate_css(self) -> str:
        """Generate comprehensive CSS styling."""
        color1, color2 = self._get_gradient_colors()
        
        return f"""* {{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}}

body {{
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, {color1} 0%, {color2} 100%);
    min-height: 100vh;
    padding: 20px;
    line-height: 1.6;
}}

.container {{
    max-width: 1400px;
    margin: 0 auto;
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    overflow: hidden;
}}

/* Low Confidence Indicator */
.low-confidence {{
    position: relative;
    border: 2px dashed #ff9800 !important;
    background: repeating-linear-gradient(
        45deg,
        transparent,
        transparent 10px,
        rgba(255, 152, 0, 0.05) 10px,
        rgba(255, 152, 0, 0.05) 20px
    ) !important;
}}

.low-confidence::before {{
    content: "⚠ Low Confidence Detection";
    position: absolute;
    top: -12px;
    left: 10px;
    background: #ff9800;
    color: white;
    padding: 2px 10px;
    font-size: 11px;
    border-radius: 10px;
    font-weight: 600;
    z-index: 10;
}}

.low-confidence-inline {{
    border: 2px dashed #ff9800 !important;
    background-color: rgba(255, 152, 0, 0.08) !important;
    box-shadow: 0 0 10px rgba(255, 152, 0, 0.2) !important;
}}

/* Navbar Styling */
.navbar {{
    background: linear-gradient(90deg, {color1} 0%, {color2} 100%);
    padding: 30px 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}}

.navbar.low-confidence {{
    background: linear-gradient(90deg, #ff9800 0%, #f57c00 100%);
}}

.navbar h1 {{
    color: white;
    font-size: 28px;
    font-weight: 600;
}}

.nav-links {{
    display: flex;
    gap: 30px;
}}

.nav-links a {{
    color: white;
    text-decoration: none;
    font-size: 16px;
    transition: opacity 0.3s;
}}

.nav-links a:hover {{
    opacity: 0.8;
}}

/* Row Section - wraps each row group */
.row-section {{
    padding: 40px;
}}

.row-section:nth-child(even) {{
    background: #f8f9fa;
}}

/* Two Column Layout */
.two-column-layout {{
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: start;
}}

.column-left {{
    display: flex;
    flex-direction: column;
    gap: 25px;
}}

.column-right {{
    display: flex;
    flex-direction: column;
    gap: 25px;
}}

/* Full Width Layout */
.full-width-layout {{
    display: flex;
    flex-direction: column;
    gap: 25px;
}}

/* Button Styling */
.button {{
    background: linear-gradient(135deg, {color1} 0%, {color2} 100%);
    color: white;
    border: none;
    padding: 18px 36px;
    font-size: 16px;
    font-weight: 600;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
    align-self: flex-start;
}}

.button:hover {{
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.6);
}}

.button:active {{
    transform: translateY(0);
}}

/* Checkbox Styling */
.checkbox-group {{
    background: #f8f9fa;
    padding: 25px;
    border-radius: 12px;
    border: 2px solid #e0e0e0;
}}

.checkbox-item {{
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 15px;
}}

.checkbox-item:last-child {{
    margin-bottom: 0;
}}

input[type="checkbox"] {{
    width: 24px;
    height: 24px;
    cursor: pointer;
    accent-color: {color1};
}}

.checkbox-item label {{
    font-size: 16px;
    color: #333;
    cursor: pointer;
}}

/* Image Styling */
.image-container {{
    background: linear-gradient(135deg, {color1}22 0%, {color2}33 100%);
    border-radius: 12px;
    padding: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 250px;
    border: 2px dashed {color1};
}}

.image-placeholder {{
    text-align: center;
    color: {color1};
}}

.image-placeholder svg {{
    width: 100px;
    height: 100px;
    margin-bottom: 20px;
    opacity: 0.6;
}}

.image-placeholder p {{
    font-size: 18px;
    font-weight: 500;
}}

/* Text Styling */
.text-block {{
    background: white;
    padding: 25px;
    border-radius: 12px;
    border-left: 4px solid {color1};
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}}

.text-block h3 {{
    color: #333;
    margin-bottom: 10px;
    font-size: 20px;
}}

.text-block p {{
    color: #666;
    line-height: 1.6;
    font-size: 15px;
}}

/* Textfield Styling */
.textfield {{
    width: 100%;
    padding: 18px 24px;
    font-size: 16px;
    border: 2px solid #e0e0e0;
    border-radius: 12px;
    transition: all 0.3s;
}}

.textfield:focus {{
    outline: none;
    border-color: {color1};
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}}

/* Paragraph Styling */
.paragraph {{
    color: #555;
    line-height: 1.8;
    font-size: 16px;
    padding: 25px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}}

.paragraph h2 {{
    color: #333;
    margin-bottom: 20px;
    font-size: 26px;
    border-bottom: 3px solid {color1};
    padding-bottom: 15px;
}}

.paragraph p {{
    margin-bottom: 15px;
}}

/* Responsive Design */
@media (max-width: 1024px) {{
    .two-column-layout {{
        grid-template-columns: 1fr;
    }}
}}

@media (max-width: 768px) {{
    .navbar {{
        flex-direction: column;
        gap: 20px;
        text-align: center;
    }}
    
    .nav-links {{
        flex-direction: column;
        gap: 15px;
    }}
    
    .row-section {{
        padding: 20px;
    }}
    
    .two-column-layout {{
        gap: 20px;
    }}
}}"""
    
    def _generate_navbar_html(self, element: Dict) -> str:
        """Generate navbar HTML."""
        confidence_class = ' low-confidence' if self._is_low_confidence(element) else ''
        confidence = element.get('confidence', 1.0)
        
        return f"""<nav class="navbar{confidence_class}">
    <h1>Modern Dashboard</h1>
    <div class="nav-links">
        <a href="#home">Home</a>
        <a href="#features">Features</a>
        <a href="#about">About</a>
        <a href="#contact">Contact</a>
    </div>
</nav>
<!-- Detection confidence: {confidence:.1%} -->"""
    
    def _generate_button_html(self, element: Dict) -> str:
        """Generate button HTML."""
        confidence_class = ' low-confidence-inline' if self._is_low_confidence(element) else ''
        return f'<button class="button{confidence_class}">Get Started</button>'
    
    def _generate_checkbox_html(self, element: Dict) -> str:
        """Generate checkbox group HTML."""
        confidence_class = ' low-confidence' if self._is_low_confidence(element) else ''
        
        return f"""<div class="checkbox-group{confidence_class}">
    <div class="checkbox-item">
        <input type="checkbox" id="option1_{element.get('id', '0')}" checked>
        <label for="option1_{element.get('id', '0')}">Enable notifications</label>
    </div>
    <div class="checkbox-item">
        <input type="checkbox" id="option2_{element.get('id', '0')}">
        <label for="option2_{element.get('id', '0')}">Auto-save changes</label>
    </div>
    <div class="checkbox-item">
        <input type="checkbox" id="option3_{element.get('id', '0')}" checked>
        <label for="option3_{element.get('id', '0')}">Dark mode</label>
    </div>
</div>"""
    
    def _generate_image_html(self, element: Dict) -> str:
        """Generate image placeholder HTML."""
        confidence_class = ' low-confidence' if self._is_low_confidence(element) else ''
        
        return f"""<div class="image-container{confidence_class}">
    <div class="image-placeholder">
        <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
            <rect x="3" y="3" width="18" height="18" rx="2" ry="2"/>
            <circle cx="8.5" cy="8.5" r="1.5"/>
            <polyline points="21 15 16 10 5 21"/>
        </svg>
        <p>Image Placeholder</p>
    </div>
</div>"""
    
    def _generate_text_html(self, element: Dict) -> str:
        """Generate text block HTML."""
        confidence_class = ' low-confidence' if self._is_low_confidence(element) else ''
        
        return f"""<div class="text-block{confidence_class}">
    <h3>Quick Tip</h3>
    <p>Use the search bar above to quickly find what you're looking for. All features are just a click away!</p>
</div>"""
    
    def _generate_textfield_html(self, element: Dict) -> str:
        """Generate textfield HTML."""
        confidence_class = ' low-confidence-inline' if self._is_low_confidence(element) else ''
        return f'<input type="text" class="textfield{confidence_class}" placeholder="Type Anything you want...">'
    
    def _generate_paragraph_html(self, element: Dict) -> str:
        """Generate paragraph HTML."""
        confidence_class = ' low-confidence' if self._is_low_confidence(element) else ''
        
        return f"""<div class="paragraph{confidence_class}">
    <h2>Welcome to Your Dashboard</h2>
    <p>This modern interface brings together all the tools you need in one beautiful, cohesive design. Our goal is to make your workflow as smooth and efficient as possible.</p>
    <p>With intuitive navigation and powerful features at your fingertips, you can focus on what matters most. Whether you're managing projects, analyzing data, or collaborating with your team, everything is designed to work seamlessly together.</p>
    <p>The responsive layout adapts to any screen size, ensuring you have a consistent experience across all your devices. Customize your settings using the options on the left to make this space truly yours.</p>
    <p>We've carefully crafted every element to provide both beauty and functionality. The clean design reduces clutter while maintaining all the power you need to be productive.</p>
    <p>Start exploring the features available to you, and discover how this platform can transform the way you work. If you need any help, our comprehensive documentation and support team are always available.</p>
</div>"""
    
    def _generate_element_html(self, element: Dict) -> str:
        """Generate HTML for a single element based on its type."""
        element_type = element['type'].lower()
        
        generators = {
            'navbar': self._generate_navbar_html,
            'button': self._generate_button_html,
            'checkbox': self._generate_checkbox_html,
            'image': self._generate_image_html,
            'text': self._generate_text_html,
            'textfield': self._generate_textfield_html,
            'paragraph': self._generate_paragraph_html
        }
        
        generator = generators.get(element_type)
        if generator:
            return generator(element)
        
        # Default fallback
        confidence_class = ' low-confidence' if self._is_low_confidence(element) else ''
        return f'<div class="default-element{confidence_class}">Element: {element_type}</div>'
    
    def _organize_layout(self) -> Dict[str, Any]:
        """
        Organize elements into layout sections.
        
        Returns:
            Dict with 'header' (navbar elements) and 'row_groups' (list of row sections)
        """
        layout = {
            'header': [],
            'row_groups': []
        }
        
        # Separate navbar elements from others
        non_navbar_elements = []
        for element in self.elements:
            if element['type'].lower() == 'navbar':
                layout['header'].append(element)
            else:
                non_navbar_elements.append(element)
        
        # Group non-navbar elements by rows
        if non_navbar_elements:
            # Temporarily set elements to non-navbar for grouping
            original_elements = self.elements
            self.elements = non_navbar_elements
            row_groups = self._group_elements_by_rows()
            self.elements = original_elements
            
            # Classify each row group
            for group in row_groups:
                left_elements = []
                right_elements = []
                center_elements = []
                
                for element in group:
                    position = self._classify_element_position(element)
                    if position == 'left':
                        left_elements.append(element)
                    elif position == 'right':
                        right_elements.append(element)
                    else:  # center
                        center_elements.append(element)
                
                layout['row_groups'].append({
                    'left': left_elements,
                    'right': right_elements,
                    'center': center_elements
                })
        
        return layout
    
    def _generate_row_section_html(self, row_data: Dict) -> str:
        """Generate HTML for a single row section."""
        left_elements = row_data['left']
        right_elements = row_data['right']
        center_elements = row_data['center']
        
        html_parts = []
        
        # If there are center elements, render them in full-width layout
        if center_elements:
            html_parts.append('<div class="full-width-layout">')
            for element in center_elements:
                html_parts.append(self._generate_element_html(element))
            html_parts.append('</div>')
        
        # If there are left or right elements, use two-column layout
        if left_elements or right_elements:
            html_parts.append('<div class="two-column-layout">')
            
            # Left column
            html_parts.append('<div class="column-left">')
            for element in left_elements:
                html_parts.append(self._generate_element_html(element))
            html_parts.append('</div>')
            
            # Right column
            html_parts.append('<div class="column-right">')
            for element in right_elements:
                html_parts.append(self._generate_element_html(element))
            html_parts.append('</div>')
            
            html_parts.append('</div>')
        
        return '\n'.join(html_parts)
    
    def _generate_body_html(self) -> str:
        """Generate the body HTML content using flexible row-based layout."""
        layout = self._organize_layout()
        
        html_parts = ['<div class="container">']
        
        # Header section (navbar only)
        for element in layout['header']:
            html_parts.append(self._generate_element_html(element))
        
        # Row sections
        for i, row_data in enumerate(layout['row_groups']):
            html_parts.append(f'<div class="row-section" data-row-group="{i}">')
            html_parts.append(self._generate_row_section_html(row_data))
            html_parts.append('</div>')
        
        html_parts.append('</div>')  # Close container
        
        return '\n'.join(html_parts)
    
    def generate_html(self, output_path: str = 'output.html'):
        """Generate complete HTML file."""
        css = self._generate_css()
        body = self._generate_body_html()
        
        # Count low confidence elements
        low_conf_count = sum(1 for e in self.elements if self._is_low_confidence(e))
        
        # Get layout stats
        layout = self._organize_layout()
        total_row_groups = len(layout['row_groups'])
        
        html_template = f"""<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Generated UI Layout</title>
    <style>
{css}
    </style>
</head>
<body>
{body}
    
    <!-- Generation Info -->
    <!-- Total elements: {len(self.elements)} -->
    <!-- Low confidence elements: {low_conf_count} -->
    <!-- Row groups: {total_row_groups} -->
    <!-- Grid: {self.grid_system.get('columns', 'N/A')}x{self.grid_system.get('rows', 'N/A')} -->
</body>
</html>"""
        
        # Write to file
        output_file = Path(output_path)
        output_file.write_text(html_template, encoding='utf-8')
        
        print(f"✓ HTML file generated successfully: {output_file.absolute()}")
        print(f"✓ Total elements processed: {len(self.elements)}")
        print(f"✓ Element types: {', '.join(set(e['type'] for e in self.elements))}")
        print(f"✓ Row groups created: {total_row_groups}")
        print(f"✓ Low confidence elements: {low_conf_count}/{len(self.elements)}")
        if low_conf_count > 0:
            print(f"  ⚠ Elements with confidence < {self.LOW_CONFIDENCE_THRESHOLD:.0%} are marked with orange dashed borders")
        
        return html_template


def main():
    """Main function to run the generator."""
    import sys
    
    # Check if JSON file path is provided
    if len(sys.argv) < 2:
        print("Usage: python CodingModule.py <json_file_path> [output_html_path]")
        print("Example: python CodingModule.py wireframe_output.json output.html")
        sys.exit(1)
    
    json_path = sys.argv[1]
    output_path = sys.argv[2] if len(sys.argv) > 2 else 'output.html'
    
    # Validate JSON file exists
    if not Path(json_path).exists():
        print(f"Error: JSON file not found: {json_path}")
        sys.exit(1)
    
    try:
        # Generate HTML
        generator = HTMLGenerator(json_path)
        generator.generate_html(output_path)
        
    except json.JSONDecodeError as e:
        print(f"Error: Invalid JSON file - {e}")
        sys.exit(1)
    except Exception as e:
        print(f"Error: {e}")
        sys.exit(1)


if __name__ == "__main__":
    main()