"""
Gradio interface for Rabbinic Hebrew/Aramaic Embedding Evaluation.

A Hugging Face Space for evaluating embedding models on cross-lingual
retrieval between Hebrew/Aramaic source texts and English translations.
"""

import os
import threading
from datetime import datetime

import gradio as gr
import pandas as pd
import plotly.graph_objects as go

from data_loader import load_benchmark_dataset, get_benchmark_stats
from models import (
    API_MODELS,
    ALL_MODELS,
    load_model,
    validate_model_id,
    requires_api_key,
    api_key_optional,
    get_api_key_type,
    get_api_key_env_var,
)
from evaluation import (
    EvaluationResults,
    evaluate_model,
    evaluate_model_streaming,
    compute_similarity_matrix,
    get_rank_distribution,
)
from leaderboard import (
    load_leaderboard as load_leaderboard_from_hub,
    add_result as add_result_to_hub,
)
from jobs import (
    Job,
    create_job,
    get_job,
    update_job_progress,
    complete_job,
    fail_job,
    delete_job,
    cleanup_old_jobs,
    cleanup_stale_jobs,
)

# HuggingFace Dataset ID for benchmark data
BENCHMARK_DATASET_ID = "Sefaria/Rabbinic-Hebrew-English-Pairs"

# Global state
_benchmark_data = None


def load_benchmark():
    """Load benchmark data from HuggingFace Hub, with fallback to sample data."""
    global _benchmark_data
    
    if _benchmark_data is not None:
        return _benchmark_data
    
    try:
        _benchmark_data = load_benchmark_dataset(BENCHMARK_DATASET_ID)
        print(f"Loaded {len(_benchmark_data)} benchmark pairs from {BENCHMARK_DATASET_ID}")
    except Exception as e:
        print(f"Failed to load benchmark: {e}")
        print("Using sample data for testing")
        # Create minimal sample data for testing
        _benchmark_data = [
            {
                "ref": "Sample.1",
                "he": "בראשית ברא אלהים את השמים ואת הארץ",
                "en": "In the beginning God created the heaven and the earth",
                "category": "Sample",
            },
            {
                "ref": "Sample.2",
                "he": "והארץ היתה תהו ובהו וחשך על פני תהום",
                "en": "And the earth was without form, and void; and darkness was upon the face of the deep",
                "category": "Sample",
            },
        ]
    
    return _benchmark_data


def load_leaderboard():
    """Load leaderboard from HuggingFace Hub."""
    return load_leaderboard_from_hub()


def add_to_leaderboard(results: EvaluationResults):
    """Add evaluation results to leaderboard on HuggingFace Hub."""
    entry = results.to_dict()
    entry["timestamp"] = datetime.now().isoformat()
    
    # Add to Hub (handles deduplication and sorting internally)
    success = add_result_to_hub(entry)
    
    if not success:
        print("Note: Results saved locally but not persisted to Hub (no HF_TOKEN)")


def format_leaderboard_df():
    """Format leaderboard as pandas DataFrame for display."""
    leaderboard = load_leaderboard()
    
    if not leaderboard:
        return pd.DataFrame(columns=[
            "#", "Model", "MRR", "R@1", "R@5", "R@10", 
            "Bitext", "TrueSim", "RandSim", "N"
        ])
    
    rows = []
    for i, entry in enumerate(leaderboard, 1):
        rows.append({
            "#": i,
            "Model": entry.get("model_name", entry["model_id"]),
            "MRR": f"{entry['mrr']:.3f}",
            "R@1": f"{entry['recall_at_1']:.1%}",
            "R@5": f"{entry['recall_at_5']:.1%}",
            "R@10": f"{entry['recall_at_10']:.1%}",
            "Bitext": f"{entry['bitext_accuracy']:.1%}",
            "TrueSim": f"{entry['avg_true_pair_similarity']:.3f}",
            "RandSim": f"{entry['avg_random_pair_similarity']:.3f}",
            "N": entry["num_pairs"],
        })
    
    return pd.DataFrame(rows)


def run_evaluation_background(job_id: str, model_id: str, api_key: str, max_pairs: int):
    """
    Run evaluation in background thread, writing progress to job file.

    This function runs in a daemon thread. It writes progress updates to a
    persistent job file so that the UI can poll for status even if the
    original HTTP connection times out.
    """
    try:
        update_job_progress(job_id, "⏳ Loading benchmark data...", 0.0)
        benchmark = load_benchmark()

        if max_pairs and max_pairs < len(benchmark):
            benchmark = benchmark[:max_pairs]

        update_job_progress(job_id, f"⏳ Loading model: {model_id}...", 0.05)
        model = load_model(model_id, api_key=api_key if api_key else None)

        # Progress callback for evaluation - writes to job file
        def progress_callback(progress_frac: float, msg: str):
            # Scale progress: model loading is 0-10%, evaluation is 10-95%, saving is 95-100%
            scaled_progress = 0.10 + (progress_frac * 0.85)
            update_job_progress(job_id, msg, scaled_progress)

        update_job_progress(job_id, "⏳ Starting evaluation...", 0.10)
        results = evaluate_model(
            model,
            benchmark,
            batch_size=32,
            progress_callback=progress_callback,
        )

        update_job_progress(job_id, "⏳ Saving results to leaderboard...", 0.95)
        add_to_leaderboard(results)

        # Format results summary
        summary = f"""## Results for {results.model_name}

| Metric | Value |
|--------|-------|
| **MRR** | {results.mrr:.4f} |
| **Recall@1** | {results.recall_at_1:.1%} |
| **Recall@5** | {results.recall_at_5:.1%} |
| **Recall@10** | {results.recall_at_10:.1%} |
| **Bitext Accuracy** | {results.bitext_accuracy:.1%} |
| **Avg True Pair Sim** | {results.avg_true_pair_similarity:.4f} |
| **Avg Random Pair Sim** | {results.avg_random_pair_similarity:.4f} |
| **Pairs Evaluated** | {results.num_pairs:,} |
"""

        complete_job(job_id, summary)

    except Exception as e:
        fail_job(job_id, str(e))


def start_evaluation(
    model_choice: str,
    custom_model_id: str,
    api_key: str,
    max_pairs: int,
):
    """
    Start evaluation in background and return job ID.

    Creates a persistent job file and starts a background thread.
    The job file allows the UI to poll for status even if the
    HTTP connection times out.
    """
    # Determine which model to use
    if model_choice == "custom":
        model_id = custom_model_id.strip()
        is_valid, error = validate_model_id(model_id)
        if not is_valid:
            return (
                "",  # job_id
                f"❌ {error}",
                f"❌ Invalid model ID: {error}",
                format_leaderboard_df(),
                gr.update(visible=False),  # check_status_btn
                gr.update(visible=False, value=""),  # job_id_display
            )
    else:
        model_id = model_choice

    # Check if API key is required but not provided
    if requires_api_key(model_id):
        api_key = api_key.strip() if api_key else ""
        env_var = get_api_key_env_var(model_id)
        key_type = get_api_key_type(model_id)

        if not api_key and not os.environ.get(env_var) and not api_key_optional(model_id):
            return (
                "",
                "❌ API key required",
                f"❌ API key required for {model_id}. Please enter your {key_type.upper()} API key or set the {env_var} environment variable.",
                format_leaderboard_df(),
                gr.update(visible=False),
                gr.update(visible=False, value=""),
            )

    # Get model display name
    model_name = model_id
    if model_id in ALL_MODELS:
        model_name = ALL_MODELS[model_id].get("name", model_id)

    # Create persistent job
    job = create_job(model_id=model_id, model_name=model_name, max_pairs=max_pairs)

    # Start background thread
    thread = threading.Thread(
        target=run_evaluation_background,
        args=(job.job_id, model_id, api_key, max_pairs),
        daemon=True,
    )
    thread.start()

    return (
        job.job_id,
        "⏳ Evaluation started! Click 'Check Status' to see progress (auto-refreshes every 5 seconds).",
        "",
        gr.update(),  # Don't update leaderboard yet
        gr.update(visible=True),  # Show check_status_btn
        gr.update(visible=True, value=f"Job ID: {job.job_id[:8]}..."),  # Show job_id_display
    )


def check_job_status(job_id: str):
    """
    Check job status by reading the job file.

    This is a stateless operation - each check reads fresh data from disk.
    Uses regular HTTP POST (not SSE) so it survives HF Spaces proxy timeouts.
    """
    if not job_id:
        return (
            "",
            "",
            gr.update(),
            gr.update(visible=False),  # Hide check button
            gr.update(visible=False, value=""),  # Hide job ID
        )

    job = get_job(job_id)

    if job is None:
        # Job not found - might have been cleaned up or never existed
        return (
            "⚠️ Job not found. It may have expired or been cleaned up.",
            "",
            gr.update(),
            gr.update(visible=False),
            gr.update(visible=False, value=""),
        )

    if job.status == "completed":
        # Job completed successfully
        # Clean up the job file after retrieving results
        delete_job(job_id)

        return (
            job.progress,
            job.result or "",
            format_leaderboard_df(),
            gr.update(visible=False),  # Hide check button
            gr.update(visible=False, value=""),  # Hide job ID
        )

    elif job.status == "failed":
        # Job failed
        error_msg = job.error or "Unknown error"
        # Clean up the job file
        delete_job(job_id)

        return (
            job.progress,
            f"❌ Error: {error_msg}",
            format_leaderboard_df(),
            gr.update(visible=False),  # Hide check button
            gr.update(visible=False, value=""),  # Hide job ID
        )

    else:
        # Still running (status is "pending" or "running")
        # Include progress percentage in the status message
        pct = int(job.progress_pct * 100)
        progress_with_pct = f"{job.progress} ({pct}%)"

        return (
            progress_with_pct,
            "",
            gr.update(),  # Don't update leaderboard yet
            gr.update(visible=True),  # Keep check button visible
            gr.update(visible=True),  # Keep job ID visible
        )


def create_leaderboard_comparison():
    """Create comparison chart of all models on leaderboard."""
    leaderboard = load_leaderboard()
    
    if len(leaderboard) < 2:
        return None
    
    models = [e.get("model_name", e["model_id"]) for e in leaderboard]
    mrr = [e["mrr"] for e in leaderboard]
    r1 = [e["recall_at_1"] for e in leaderboard]
    r5 = [e["recall_at_5"] for e in leaderboard]
    r10 = [e["recall_at_10"] for e in leaderboard]
    bitext = [e["bitext_accuracy"] for e in leaderboard]
    
    fig = go.Figure()
    
    fig.add_trace(go.Bar(name="MRR", x=models, y=mrr, marker_color="#2E86AB"))
    fig.add_trace(go.Bar(name="R@1", x=models, y=r1, marker_color="#A23B72"))
    fig.add_trace(go.Bar(name="R@5", x=models, y=r5, marker_color="#F18F01"))
    fig.add_trace(go.Bar(name="R@10", x=models, y=r10, marker_color="#C73E1D"))
    fig.add_trace(go.Bar(name="Bitext Acc", x=models, y=bitext, marker_color="#6B5B95"))
    
    fig.update_layout(
        title="Model Comparison",
        yaxis_title="Score",
        yaxis_range=[0, 1],
        barmode="group",
        template="plotly_white",
        height=400,
    )
    
    return fig


def update_model_inputs_visibility(choice):
    """Show/hide custom model input and API key based on selection."""
    show_custom = (choice == "custom")
    show_api_key = requires_api_key(choice) if choice != "custom" else False
    
    # Update API key label based on model type
    if show_api_key:
        key_type = get_api_key_type(choice)
        env_var = get_api_key_env_var(choice)
        is_optional = api_key_optional(choice)
        
        if key_type == "voyage":
            label = "Voyage AI API Key"
            placeholder = f"Enter your Voyage AI API key (or set {env_var} env var)"
        elif key_type == "gemini":
            label = "Gemini API Key (optional if using gcloud)"
            placeholder = f"Leave blank if using gcloud ADC, or enter API key / set {env_var}"
        elif key_type == "cohere":
            label = "Cohere API Key"
            placeholder = f"Enter your Cohere API key (or set {env_var} env var)"
        else:
            label = "OpenAI API Key"
            placeholder = f"Enter your OpenAI API key (or set {env_var} env var)"
        return (
            gr.update(visible=show_custom),
            gr.update(visible=show_api_key, label=label, placeholder=placeholder),
        )
    
    return (
        gr.update(visible=show_custom),
        gr.update(visible=show_api_key),
    )


# Build the Gradio interface
def create_app():
    """Create and return the Gradio app."""

    # Clean up any stale jobs from previous runs (e.g., if Space restarted mid-evaluation)
    print("Cleaning up stale jobs...")
    cleanup_stale_jobs(stale_minutes=30)
    cleanup_old_jobs(max_age_hours=24)

    # Get all model choices - custom first, then API models
    model_choices = []

    # Custom option first
    model_choices.append(("⚙️ Custom Model (enter HuggingFace ID below)", "custom"))

    # API models
    for model_id, info in API_MODELS.items():
        model_choices.append((f"🌐 {info['name']}", model_id))

    # Load initial data
    load_benchmark()
    load_leaderboard()
    benchmark_stats = get_benchmark_stats(_benchmark_data) if _benchmark_data else {}
    
    with gr.Blocks(
        title="Rabbinic Embedding Benchmark",
        theme=gr.themes.Soft(
            primary_hue="blue",
            secondary_hue="orange",
            font=gr.themes.GoogleFont("Source Sans Pro"),
        ),
        css="""
        .main-header {
            text-align: center;
            margin-bottom: 1rem;
        }
        .stats-box {
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            padding: 1rem;
            border-radius: 8px;
            margin: 0.5rem 0;
        }
        """,
    ) as app:
        
        # Hidden state for job tracking (persists job ID across poll requests)
        job_id_state = gr.State("")
        
        gr.Markdown(
            """
            # 📚 Rabbinic Hebrew/Aramaic Embedding Benchmark
            
            Evaluate embedding models on cross-lingual retrieval between Hebrew/Aramaic 
            source texts and their English translations from Sefaria.
            
            **How it works:** Given a Hebrew/Aramaic text, can the model find its correct 
            English translation from a pool of candidates? Models that excel at this task 
            produce high-quality embeddings for Rabbinic literature.
            """,
            elem_classes=["main-header"],
        )
        
        with gr.Row():
            with gr.Column(scale=1):
                gr.Markdown(f"""
                ### 📊 Benchmark Stats
                - **Total Pairs:** {benchmark_stats.get('total_pairs', 'N/A'):,}
                - **Categories:** {len(benchmark_stats.get('categories', {}))}
                - **Avg Hebrew Length:** {benchmark_stats.get('avg_he_length', 0):.0f} chars
                - **Dataset:** [View on Hugging Face](https://huggingface.co/datasets/{BENCHMARK_DATASET_ID})
                """)
            
            with gr.Column(scale=1):
                gr.Markdown("""
                ### 📏 Metrics
                - **MRR:** Mean Reciprocal Rank
                - **R@k:** Recall at k (correct in top k)
                - **Bitext Acc:** True vs random pair classification
                """)
        
        gr.Markdown("---")
        
        with gr.Tabs(selected=0):  # Default to Leaderboard tab
            with gr.TabItem("🏆 Leaderboard"):
                leaderboard_table = gr.Dataframe(
                    value=format_leaderboard_df(),
                    label="Model Rankings",
                    interactive=False,
                )
                
                refresh_btn = gr.Button("🔄 Refresh Leaderboard")
                
                comparison_plot = gr.Plot(
                    value=create_leaderboard_comparison(),
                    label="Model Comparison"
                )
            
            with gr.TabItem("🔬 Evaluate Model"):
                with gr.Row():
                    with gr.Column(scale=2):
                        model_dropdown = gr.Dropdown(
                            choices=model_choices,
                            value="custom",
                            label="Select Model",
                            info="Enter a HuggingFace model ID or choose an API model",
                        )

                        custom_model_input = gr.Textbox(
                            label="HuggingFace Model ID",
                            placeholder="e.g., intfloat/multilingual-e5-large",
                            visible=True,  # Visible by default since "custom" is selected
                        )
                        
                        api_key_input = gr.Textbox(
                            label="API Key",
                            placeholder="Enter your API key (or set appropriate env var)",
                            type="password",
                            visible=False,
                            info="Required for API-based models (OpenAI, Voyage AI). Your key is not stored.",
                        )
                        
                        total_pairs = benchmark_stats.get('total_pairs', 1000)
                        max_pairs_slider = gr.Slider(
                            minimum=100,
                            maximum=total_pairs,
                            value=total_pairs,
                            step=100,
                            label="Max Pairs to Evaluate",
                            info="Use fewer pairs for faster evaluation",
                        )
                    
                    with gr.Column(scale=3):
                        evaluate_btn = gr.Button(
                            "🚀 Run Evaluation",
                            variant="primary",
                            size="lg",
                        )

                        # Manual refresh button - visible when a job is running
                        # This uses regular HTTP POST (not SSE) so it survives proxy timeouts
                        with gr.Row():
                            check_status_btn = gr.Button(
                                "🔄 Check Status",
                                variant="secondary",
                                size="sm",
                                visible=False,
                            )
                            job_id_display = gr.Textbox(
                                label="",
                                visible=False,
                                interactive=False,
                                container=False,
                                scale=2,
                            )

                        status_text = gr.Markdown("")

                        results_markdown = gr.Markdown("")
        
        gr.Markdown("""
        ---
        ### About
        
        This benchmark evaluates embedding models for Rabbinic Hebrew and Aramaic texts using 
        cross-lingual retrieval. 

        All texts and translations sourced from [Sefaria](https://www.sefaria.org).
        """)
        
        # Event handlers
        model_dropdown.change(
            fn=update_model_inputs_visibility,
            inputs=[model_dropdown],
            outputs=[custom_model_input, api_key_input],
        )

        # Start evaluation: creates persistent job file and spawns background thread.
        # Returns immediately with job_id so UI doesn't timeout waiting.
        evaluate_btn.click(
            fn=start_evaluation,
            inputs=[model_dropdown, custom_model_input, api_key_input, max_pairs_slider],
            outputs=[job_id_state, status_text, results_markdown, leaderboard_table, check_status_btn, job_id_display],
        ).then(
            # Start JavaScript auto-polling after evaluation begins
            fn=None,
            inputs=None,
            outputs=None,
            js="""
            () => {
                // Clear any existing interval
                if (window.jobPollInterval) {
                    clearInterval(window.jobPollInterval);
                }
                console.log('[Auto-poll] Starting polling every 5 seconds');
                // Auto-click the check status button every 5 seconds
                window.jobPollInterval = setInterval(() => {
                    // Find button by looking for "Check Status" text
                    const buttons = document.querySelectorAll('button');
                    let checkBtn = null;
                    for (const btn of buttons) {
                        if (btn.textContent.includes('Check Status')) {
                            checkBtn = btn;
                            break;
                        }
                    }
                    if (checkBtn && checkBtn.offsetParent !== null) {
                        console.log('[Auto-poll] Clicking Check Status button');
                        checkBtn.click();
                    } else {
                        // Button is hidden (job done), stop polling
                        console.log('[Auto-poll] Button not visible, stopping');
                        clearInterval(window.jobPollInterval);
                        window.jobPollInterval = null;
                    }
                }, 5000);
            }
            """,
        )

        # Check status button - uses regular HTTP POST (not SSE) so it survives proxy timeouts
        check_status_btn.click(
            fn=check_job_status,
            inputs=[job_id_state],
            outputs=[status_text, results_markdown, leaderboard_table, check_status_btn, job_id_display],
        )
        
        def refresh_leaderboard():
            """Force refresh leaderboard from Hub."""
            from leaderboard import clear_cache
            clear_cache()  # Clear cache to force fresh load
            return (format_leaderboard_df(), create_leaderboard_comparison())
        
        refresh_btn.click(
            fn=refresh_leaderboard,
            outputs=[leaderboard_table, comparison_plot],
        )
    
    return app


# Main entry point
if __name__ == "__main__":
    app = create_app()
    app.queue()
    app.launch()