"""
AI Study Assistant - Main Application
Gradio UI for the intelligent study assistant
"""

import gradio as gr
import os
from typing import Tuple
from config import (
    APP_TITLE,
    APP_DESCRIPTION,
    SUPPORTED_FILE_TYPES,
    MAX_INPUT_LENGTH,
)
from core.utils import (
    extract_text_from_file,
    truncate_text,
    format_error_message,
    log_event,
    create_directory,
)
from core.validator import InputValidator, PromptValidator
from features.summarizer import Summarizer
from features.quiz_generator import QuizGenerator
from features.explainer import Explainer
from features.doubt_solver import DoubtSolver


# Initialize features
summarizer = Summarizer()
quiz_gen = QuizGenerator()
explainer = Explainer()
doubt_solver = DoubtSolver()

# Initialize validator
validator = InputValidator()


# ===========================
# CORE PROCESSING FUNCTIONS
# ===========================

def process_file_upload(file_obj) -> Tuple[str, str]:
    """
    Process uploaded file and extract text.
    
    Args:
        file_obj: Gradio file object
    
    Returns:
        Tuple of (file_text, status_message)
    """
    if not file_obj:
        return "", "No file selected"
    
    try:
        file_path = file_obj
        
        # Validate file extension
        file_ext = os.path.splitext(file_path)[1].lower()
        if file_ext not in SUPPORTED_FILE_TYPES:
            return "", f"Unsupported file type: {file_ext}"
        
        # Extract text
        text = extract_text_from_file(file_path)
        log_event("FILE_PROCESSED", f"File type: {file_ext}, Size: {len(text)}")
        
        return text, f"✓ File processed ({len(text)} characters)"
    
    except Exception as e:
        error_msg = format_error_message(e)
        log_event("FILE_ERROR", str(e))
        return "", error_msg


def generate_summary(
    input_text: str,
    mode: str,
    use_file: bool,
    uploaded_file
) -> str:
    """Generate summary based on input."""
    try:
        text = input_text
        
        if use_file and uploaded_file:
            text, status = process_file_upload(uploaded_file)
            if not text:
                return f"Error: {status}"
        
        if not text:
            return "Error: No input provided"
        
        # Validate
        is_valid, msg = validator.validate_input(text)
        if not is_valid:
            return f"Validation Error: {msg}"
        
        log_event("FEATURE_START", f"Generating summary in {mode} mode")
        
        success, result = summarizer.summarize(text, mode=mode)
        
        if success:
            return f"""
**Summary ({mode.upper()} MODE)**

{result}

---
✓ Generation successful
"""
        else:
            return f"Error: {result}"
    
    except Exception as e:
        error_msg = format_error_message(e)
        log_event("FEATURE_ERROR", f"Summary: {str(e)}")
        return error_msg


def generate_quiz(
    input_text: str,
    num_questions: int,
    mode: str,
    use_file: bool,
    uploaded_file
) -> str:
    """Generate quiz based on input."""
    try:
        text = input_text
        
        if use_file and uploaded_file:
            text, status = process_file_upload(uploaded_file)
            if not text:
                return f"Error: {status}"
        
        if not text:
            return "Error: No input provided"
        
        is_valid, msg = validator.validate_input(text)
        if not is_valid:
            return f"Validation Error: {msg}"
        
        log_event("FEATURE_START", f"Generating {num_questions} quiz questions in {mode} mode")
        
        success, result = quiz_gen.generate_quiz(text, num_questions=num_questions, mode=mode)
        
        if success:
            return f"""
**QUIZ ({mode.upper()} MODE)**

{result}

---
✓ Quiz generated successfully
"""
        else:
            return f"Error: {result}"
    
    except Exception as e:
        error_msg = format_error_message(e)
        log_event("FEATURE_ERROR", f"Quiz: {str(e)}")
        return error_msg


def explain_concept(
    concept: str,
    context_text: str,
    mode: str,
    use_file: bool,
    uploaded_file
) -> str:
    """Explain a concept."""
    try:
        context = context_text
        
        if use_file and uploaded_file:
            context, status = process_file_upload(uploaded_file)
            if not context:
                context = context_text
        
        if not concept:
            return "Error: Please enter a concept to explain"
        
        is_valid, msg = validator.validate_input(concept)
        if not is_valid:
            return f"Validation Error: {msg}"
        
        log_event("FEATURE_START", f"Explaining '{concept}' in {mode} mode")
        
        success, result = explainer.explain(concept, context=context, mode=mode)
        
        if success:
            return f"""
**EXPLANATION - {concept.upper()} ({mode.upper()} MODE)**

{result}

---
✓ Explanation generated
"""
        else:
            return f"Error: {result}"
    
    except Exception as e:
        error_msg = format_error_message(e)
        log_event("FEATURE_ERROR", f"Explainer: {str(e)}")
        return error_msg


def solve_doubt(
    question: str,
    context_text: str,
    mode: str,
    use_file: bool,
    uploaded_file
) -> str:
    """Solve a student's doubt."""
    try:
        context = context_text
        
        if use_file and uploaded_file:
            context, status = process_file_upload(uploaded_file)
            if not context:
                context = context_text
        
        if not question:
            return "Error: Please enter your doubt/question"
        
        is_valid, msg = validator.validate_input(question)
        if not is_valid:
            return f"Validation Error: {msg}"
        
        log_event("FEATURE_START", f"Solving doubt in {mode} mode")
        
        success, result = doubt_solver.solve(question, context=context, mode=mode)
        
        if success:
            return f"""
**DOUBT SOLVER ({mode.upper()} MODE)**

{result}

---
✓ Doubt solved successfully
"""
        else:
            return f"Error: {result}"
    
    except Exception as e:
        error_msg = format_error_message(e)
        log_event("FEATURE_ERROR", f"DoubtSolver: {str(e)}")
        return error_msg


def compare_modes(input_text: str, feature_type: str, extra_input: str = "") -> str:
    """Compare outputs across different modes."""
    try:
        if not input_text and not extra_input:
            return "Error: Please provide input"
        
        modes = ["normal", "detailed", "teacher", "exam"]
        results = {}
        
        log_event("FEATURE_START", f"Comparing modes for {feature_type}")
        
        if feature_type == "Summary":
            for mode in modes:
                success, result = summarizer.summarize(input_text, mode=mode)
                results[mode] = result if success else f"Error: {result}"
        
        elif feature_type == "Explainer":
            concept = extra_input or input_text
            for mode in modes:
                success, result = explainer.explain(concept, mode=mode)
                results[mode] = result if success else f"Error: {result}"
        
        elif feature_type == "Doubt Solver":
            question = extra_input or input_text
            for mode in modes:
                success, result = doubt_solver.solve(question, mode=mode)
                results[mode] = result if success else f"Error: {result}"
        
        # Format comparison
        output = f"**MODE COMPARISON - {feature_type.upper()}**\n\n"
        for mode, result in results.items():
            output += f"## {mode.upper()} Mode\n{result}\n\n---\n\n"
        
        return output
    
    except Exception as e:
        error_msg = format_error_message(e)
        log_event("FEATURE_ERROR", f"Mode comparison: {str(e)}")
        return error_msg


# ===========================
# CREATE DIRECTORIES
# ===========================

create_directory("uploads")
create_directory("data/outputs")
create_directory("prompts/modes")
create_directory("core")
create_directory("features")


# ===========================
# BUILD GRADIO INTERFACE
# ===========================

with gr.Blocks(
    title=APP_TITLE
) as demo:
    
    # Header
    gr.Markdown(f"# 🎓 {APP_TITLE}")
    gr.Markdown(APP_DESCRIPTION)
    
    # Tabs for different features
    with gr.Tabs():
        
        # ===== TAB 1: SUMMARIZER =====
        with gr.TabItem("📄 Summary Generator"):
            with gr.Row():
                with gr.Column(scale=1):
                    gr.Markdown("### Input Options")
                    use_summary_file = gr.Checkbox(
                        label="Upload File",
                        value=False
                    )
                    summary_uploaded_file = gr.File(
                        label="Choose File (.txt, .pdf, .md)",
                        visible=False,
                        file_types=SUPPORTED_FILE_TYPES
                    )
                    summary_text_input = gr.Textbox(
                        label="Or paste text here",
                        lines=10,
                        placeholder="Paste your notes or topic here...",
                        max_lines=20
                    )
                
                with gr.Column(scale=1):
                    gr.Markdown("### Settings")
                    summary_mode = gr.Radio(
                        label="Select Mode",
                        choices=["normal", "detailed", "teacher", "exam"],
                        value="normal"
                    )
                    summary_btn = gr.Button(
                        "Generate Summary",
                        variant="primary"
                    )
            
            summary_output = gr.Textbox(
                label="✨ Your Summary",
                lines=15,
                interactive=False
            )
            
            # Toggle file upload visibility
            use_summary_file.change(
                lambda x: gr.File(visible=x),
                use_summary_file,
                summary_uploaded_file
            )
            
            # Generate on click
            summary_btn.click(
                generate_summary,
                inputs=[
                    summary_text_input,
                    summary_mode,
                    use_summary_file,
                    summary_uploaded_file
                ],
                outputs=summary_output
            )
        
        # ===== TAB 2: QUIZ GENERATOR =====
        with gr.TabItem("❓ Quiz Generator"):
            with gr.Row():
                with gr.Column(scale=1):
                    gr.Markdown("### Input")
                    use_quiz_file = gr.Checkbox(
                        label="Upload File",
                        value=False
                    )
                    quiz_uploaded_file = gr.File(
                        label="Choose File",
                        visible=False,
                        file_types=SUPPORTED_FILE_TYPES
                    )
                    quiz_text_input = gr.Textbox(
                        label="Or paste text",
                        lines=10,
                        placeholder="Paste your study material..."
                    )
                
                with gr.Column(scale=1):
                    gr.Markdown("### Quiz Settings")
                    quiz_num_questions = gr.Slider(
                        label="Number of Questions",
                        minimum=1,
                        maximum=20,
                        value=5,
                        step=1
                    )
                    quiz_mode = gr.Radio(
                        label="Mode",
                        choices=["normal", "detailed", "teacher", "exam"],
                        value="normal"
                    )
                    quiz_btn = gr.Button(
                        "Generate Quiz",
                        variant="primary"
                    )
            
            quiz_output = gr.Textbox(
                label="📋 Your Quiz",
                lines=20,
                interactive=False
            )
            
            use_quiz_file.change(
                lambda x: gr.File(visible=x),
                use_quiz_file,
                quiz_uploaded_file
            )
            
            quiz_btn.click(
                generate_quiz,
                inputs=[
                    quiz_text_input,
                    quiz_num_questions,
                    quiz_mode,
                    use_quiz_file,
                    quiz_uploaded_file
                ],
                outputs=quiz_output
            )
        
        # ===== TAB 3: EXPLAINER =====
        with gr.TabItem("🔍 Concept Explainer"):
            with gr.Row():
                with gr.Column(scale=1):
                    gr.Markdown("### What to Explain")
                    concept_input = gr.Textbox(
                        label="Concept to Explain",
                        placeholder="e.g., Photosynthesis, Recursion, etc."
                    )
                    gr.Markdown("### Optional Context")
                    use_explain_file = gr.Checkbox(
                        label="Add Context from File",
                        value=False
                    )
                    explain_uploaded_file = gr.File(
                        label="Choose File",
                        visible=False,
                        file_types=SUPPORTED_FILE_TYPES
                    )
                    context_input = gr.Textbox(
                        label="Or paste context",
                        lines=8,
                        placeholder="Paste related notes for context..."
                    )
                
                with gr.Column(scale=1):
                    gr.Markdown("### Explanation Mode")
                    explain_mode = gr.Radio(
                        label="Select Mode",
                        choices=["normal", "detailed", "teacher", "exam"],
                        value="teacher"
                    )
                    explain_btn = gr.Button(
                        "Explain Concept",
                        variant="primary"
                    )
            
            explain_output = gr.Textbox(
                label="📚 Explanation",
                lines=20,
                interactive=False
            )
            
            use_explain_file.change(
                lambda x: gr.File(visible=x),
                use_explain_file,
                explain_uploaded_file
            )
            
            explain_btn.click(
                explain_concept,
                inputs=[
                    concept_input,
                    context_input,
                    explain_mode,
                    use_explain_file,
                    explain_uploaded_file
                ],
                outputs=explain_output
            )
        
        # ===== TAB 4: DOUBT SOLVER =====
        with gr.TabItem("🧠 Doubt Solver"):
            with gr.Row():
                with gr.Column(scale=1):
                    gr.Markdown("### Your Doubt")
                    question_input = gr.Textbox(
                        label="Ask Your Question",
                        lines=8,
                        placeholder="Type your doubt or question here...",
                        max_lines=15
                    )
                    gr.Markdown("### Add Context (Optional)")
                    use_doubt_file = gr.Checkbox(
                        label="Add Notes from File",
                        value=False
                    )
                    doubt_uploaded_file = gr.File(
                        label="Choose File",
                        visible=False,
                        file_types=SUPPORTED_FILE_TYPES
                    )
                    doubt_context_input = gr.Textbox(
                        label="Or paste notes",
                        lines=8,
                        placeholder="Paste relevant notes..."
                    )
                
                with gr.Column(scale=1):
                    gr.Markdown("### Solution Mode")
                    doubt_mode = gr.Radio(
                        label="Explanation Style",
                        choices=["normal", "detailed", "teacher", "exam"],
                        value="teacher"
                    )
                    doubt_btn = gr.Button(
                        "Solve Doubt",
                        variant="primary"
                    )
            
            doubt_output = gr.Textbox(
                label="💡 Solution",
                lines=20,
                interactive=False
            )
            
            use_doubt_file.change(
                lambda x: gr.File(visible=x),
                use_doubt_file,
                doubt_uploaded_file
            )
            
            doubt_btn.click(
                solve_doubt,
                inputs=[
                    question_input,
                    doubt_context_input,
                    doubt_mode,
                    use_doubt_file,
                    doubt_uploaded_file
                ],
                outputs=doubt_output
            )
        
        # ===== TAB 5: COMPARE MODES =====
        with gr.TabItem("🔄 Mode Comparison"):
            gr.Markdown("### Compare how different modes respond to your input")
            
            with gr.Row():
                with gr.Column(scale=1):
                    compare_feature = gr.Radio(
                        label="Select Feature",
                        choices=["Summary", "Explainer", "Doubt Solver"],
                        value="Summary"
                    )
                    compare_input = gr.Textbox(
                        label="Input Text",
                        lines=10,
                        placeholder="Paste text or ask a question..."
                    )
                    compare_extra = gr.Textbox(
                        label="Extra Input (if needed)",
                        placeholder="For Explainer: concept to explain",
                        visible=False
                    )
                    compare_btn = gr.Button(
                        "Compare All Modes",
                        variant="primary"
                    )
            
            compare_output = gr.Textbox(
                label="📊 Mode Comparison Results",
                lines=25,
                interactive=False
            )
            
            # Show/hide extra input based on feature selection
            compare_feature.change(
                lambda x: gr.Textbox(visible=(x != "Summary")),
                compare_feature,
                compare_extra
            )
            
            compare_btn.click(
                compare_modes,
                inputs=[
                    compare_input,
                    compare_feature,
                    compare_extra
                ],
                outputs=compare_output
            )
    
    # Footer
    gr.Markdown("""
---
### 💡 Tips:
- **Upload files** (PDF, TXT, MD) for faster processing
- **Try different modes** to see how prompts affect responses
- **Use Doubt Solver** with context for better answers
- **Compare modes** to understand prompt engineering

### 🎓 Features Powered By:
- **Prompt Engineering**: Dynamic prompts adapt to your needs
- **Chain-of-Thought**: Step-by-step reasoning for complex problems
- **Few-Shot Learning**: Consistent, high-quality outputs
- **Input Validation**: Safety & security built-in

*Built with ❤️ for smarter studying*
""")


# ===========================
# RUN APPLICATION
# ===========================

if __name__ == "__main__":
    log_event("APP_START", "AI Study Assistant launched")
    demo.launch(
        share=False,
        server_name="0.0.0.0",
        server_port=7860,
        show_error=True,
        theme=gr.themes.Soft(),
    )