"""
JSON to CSV Converter - HuggingFace Space
Convert JSON data to CSV format with customizable options.
"""

import gradio as gr
import json
import csv
import io

def convert_json_to_csv(json_input, delimiter=",", quote_char='"', include_headers=True):
    """Convert JSON data to CSV format"""
    if not json_input.strip():
        return "Please enter JSON data", ""
    
    try:
        # Parse JSON
        data = json.loads(json_input)
        
        # Handle different JSON structures
        if isinstance(data, dict):
            # If it's a single object, convert to list with one item
            data = [data]
        elif not isinstance(data, list):
            return "❌ Invalid JSON structure: Expected object or array", ""
        
        if not data:
            return "❌ Empty JSON array", ""
        
        # Get all unique keys from all objects
        all_keys = []
        for item in data:
            if isinstance(item, dict):
                for key in item.keys():
                    if key not in all_keys:
                        all_keys.append(key)
        
        # Create CSV content
        output = io.StringIO()
        writer = csv.writer(output, delimiter=delimiter, quotechar=quote_char, 
                           quoting=csv.QUOTE_MINIMAL)
        
        # Add headers
        if include_headers:
            writer.writerow(all_keys)
        
        # Add data rows
        for item in data:
            if isinstance(item, dict):
                row = []
                for key in all_keys:
                    value = item.get(key, "")
                    # Handle nested objects/arrays
                    if isinstance(value, (dict, list)):
                        value = json.dumps(value)
                    row.append(value)
                writer.writerow(row)
            else:
                writer.writerow([item])
        
        csv_content = output.getvalue()
        output.close()
        
        success_msg = f"✅ Converted {len(data)} records to CSV\n"
        success_msg += f"📊 {len(all_keys)} columns detected\n"
        success_msg += f"📝 Columns: {', '.join(all_keys)}"
        
        return success_msg, csv_content
    
    except json.JSONDecodeError as e:
        return f"❌ Invalid JSON: {str(e)}", ""
    except Exception as e:
        return f"❌ Conversion error: {str(e)}", ""

def convert_csv_to_json(csv_input, first_row_is_header=True, delimiter=","):
    """Convert CSV data to JSON format"""
    if not csv_input.strip():
        return "Please enter CSV data", ""
    
    try:
        # Parse CSV
        lines = csv_input.strip().split('\n')
        reader = csv.reader(lines, delimiter=delimiter)
        
        rows = list(reader)
        if not rows:
            return "❌ Empty CSV data", ""
        
        result = []
        
        if first_row_is_header:
            headers = rows[0]
            data_rows = rows[1:]
        else:
            # Generate headers
            max_cols = max(len(row) for row in rows)
            headers = [f"column_{i}" for i in range(max_cols)]
            data_rows = rows
        
        # Convert rows to objects
        for row in data_rows:
            if row:  # Skip empty rows
                obj = {}
                for i, header in enumerate(headers):
                    if i < len(row):
                        value = row[i]
                        # Try to convert to appropriate type
                        if value.lower() in ('true', 'false'):
                            value = value.lower() == 'true'
                        elif value.isdigit():
                            value = int(value)
                        else:
                            try:
                                value = float(value)
                            except ValueError:
                                pass
                        obj[header] = value
                result.append(obj)
        
        json_output = json.dumps(result, indent=2)
        success_msg = f"✅ Converted {len(result)} records to JSON\n"
        success_msg += f"📊 {len(headers)} columns\n"
        success_msg += f"📝 Headers: {', '.join(headers)}"
        
        return success_msg, json_output
    
    except Exception as e:
        return f"❌ Conversion error: {str(e)}", ""

# Gradio interface
with gr.Blocks(title="JSON/CSV Converter") as demo:
    gr.Markdown("""
    # 🔄 JSON/CSV Converter
    
    Convert between JSON and CSV formats with customizable options.
    
    **Features:**
    - JSON to CSV conversion
    - CSV to JSON conversion
    - Custom delimiters and quotes
    - Handles nested objects and arrays
    - Preserves data types
    """)
    
    with gr.Tabs():
        with gr.TabItem("JSON → CSV"):
            with gr.Row():
                with gr.Column():
                    json_input = gr.Textbox(
                        label="JSON Input",
                        placeholder='Enter JSON data (e.g., [{"name": "John", "age": 30}])',
                        lines=10
                    )
                    with gr.Row():
                        delimiter = gr.Dropdown(
                            choices=[",", ";", "\t", "|"],
                            value=",",
                            label="Delimiter"
                        )
                        quote_char = gr.Dropdown(
                            choices=['"', "'", ''],
                            value='"',
                            label="Quote Character"
                        )
                    include_headers = gr.Checkbox(
                        value=True,
                        label="Include Headers"
                    )
                    json_to_csv_btn = gr.Button("Convert to CSV", variant="primary")
                
                with gr.Column():
                    json_result = gr.Textbox(label="Conversion Status", lines=3)
                    csv_output = gr.Textbox(
                        label="CSV Output",
                        lines=10,
                        interactive=False
                    )
        
        with gr.TabItem("CSV → JSON"):
            with gr.Row():
                with gr.Column():
                    csv_input = gr.Textbox(
                        label="CSV Input",
                        placeholder="name,age,city\nJohn,30,New York\nJane,25,Boston",
                        lines=10
                    )
                    with gr.Row():
                        csv_delimiter = gr.Dropdown(
                            choices=[",", ";", "\t", "|"],
                            value=",",
                            label="Delimiter"
                        )
                        first_row_header = gr.Checkbox(
                            value=True,
                            label="First Row is Header"
                        )
                    csv_to_json_btn = gr.Button("Convert to JSON", variant="primary")
                
                with gr.Column():
                    csv_result = gr.Textbox(label="Conversion Status", lines=3)
                    json_output = gr.Textbox(
                        label="JSON Output",
                        lines=10,
                        interactive=False
                    )
    
    # Event handlers
    json_to_csv_btn.click(
        fn=convert_json_to_csv,
        inputs=[json_input, delimiter, quote_char, include_headers],
        outputs=[json_result, csv_output]
    )
    
    csv_to_json_btn.click(
        fn=convert_csv_to_json,
        inputs=[csv_input, first_row_header, csv_delimiter],
        outputs=[csv_result, json_output]
    )

if __name__ == "__main__":
    demo.launch()