"""Interactive guided mode for non-technical users.

Run with: obliteratus interactive
"""

from __future__ import annotations

from rich.console import Console
from rich.panel import Panel
from rich.table import Table
from rich.prompt import Prompt, IntPrompt, Confirm

from obliteratus.presets import (
    ModelPreset,
    get_presets_by_tier,
)

console = Console()


def _detect_compute_tier() -> str:
    """Auto-detect the best compute tier based on available hardware."""
    try:
        import torch

        if torch.cuda.is_available():
            vram_gb = torch.cuda.get_device_properties(0).total_mem / (1024**3)
            if vram_gb >= 20:
                return "large"
            elif vram_gb >= 8:
                return "medium"
            else:
                return "small"
        elif hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
            return "small"  # Apple Silicon — conservative estimate
    except ImportError:
        pass
    return "tiny"  # CPU only


def _pick_compute_tier() -> str:
    """Let the user choose their compute tier with auto-detection."""
    detected = _detect_compute_tier()

    console.print()
    console.print(
        Panel(
            "[bold]What hardware are you working with?[/bold]\n\n"
            "  [cyan]1)[/cyan] [green]No GPU / basic laptop[/green]  — CPU only, < 8GB RAM\n"
            "  [cyan]2)[/cyan] [green]Basic GPU[/green]              — 4-8 GB VRAM (GTX 1060, RTX 3050, etc.)\n"
            "  [cyan]3)[/cyan] [green]Mid-range GPU[/green]          — 8-16 GB VRAM (RTX 3060/4060/4070)\n"
            "  [cyan]4)[/cyan] [green]High-end GPU[/green]           — 24+ GB VRAM (RTX 3090/4090, A100)\n",
            title="Step 1: Hardware",
        )
    )

    tier_map = {"1": "tiny", "2": "small", "3": "medium", "4": "large"}
    detected_num = {"tiny": "1", "small": "2", "medium": "3", "large": "4"}[detected]

    choice = Prompt.ask(
        f"  Your choice (auto-detected: [bold]{detected_num}[/bold])",
        choices=["1", "2", "3", "4"],
        default=detected_num,
    )
    return tier_map[choice]


def _pick_model(tier: str) -> ModelPreset:
    """Show models for the chosen tier and let the user pick."""
    presets = get_presets_by_tier(tier)
    # Also show one tier below as safe options
    tier_order = ["tiny", "small", "medium", "large"]
    idx = tier_order.index(tier)
    if idx > 0:
        presets = get_presets_by_tier(tier_order[idx - 1]) + presets

    console.print()
    table = Table(title="Recommended models for your hardware")
    table.add_column("#", style="cyan", justify="right")
    table.add_column("Model", style="green")
    table.add_column("Params", justify="right")
    table.add_column("Tier", style="yellow")
    table.add_column("Description")

    for i, p in enumerate(presets, 1):
        table.add_row(str(i), p.name, p.params, p.tier.upper(), p.description)

    console.print(table)

    choice = IntPrompt.ask(
        "\n  Pick a model number (or 0 to enter a custom HuggingFace model ID)",
        default=1,
    )

    if choice == 0:
        custom_id = Prompt.ask("  Enter HuggingFace model ID (e.g. 'gpt2')")
        return ModelPreset(
            name=custom_id,
            hf_id=custom_id,
            description="Custom model",
            tier=tier,
            params="unknown",
            recommended_dtype="float16" if tier != "tiny" else "float32",
        )

    if 1 <= choice <= len(presets):
        return presets[choice - 1]

    console.print("[red]Invalid choice, using first model.[/red]")
    return presets[0]


def _pick_study_preset():
    """Let the user pick an ablation preset or go custom.

    Returns a StudyPreset if chosen, or None for custom mode.
    """
    from obliteratus.study_presets import list_study_presets

    presets = list_study_presets()

    console.print()
    table = Table(title="Ablation Presets — Pick a recipe or go custom")
    table.add_column("#", style="cyan", justify="right")
    table.add_column("Name", style="green")
    table.add_column("Strategies", style="yellow")
    table.add_column("Samples", justify="right")
    table.add_column("Description")

    for i, p in enumerate(presets, 1):
        strats = ", ".join(s["name"] for s in p.strategies)
        table.add_row(str(i), p.name, strats, str(p.max_samples), p.description)
    table.add_row(
        str(len(presets) + 1), "Custom", "pick your own", "—",
        "Manually choose strategies and settings",
    )

    console.print(table)

    choice = IntPrompt.ask("\n  Pick a preset number", default=1)

    if 1 <= choice <= len(presets):
        return presets[choice - 1]
    return None  # custom mode


def _pick_strategies() -> list[dict]:
    """Let the user choose which ablation strategies to run (custom mode)."""
    console.print()
    console.print(
        Panel(
            "[bold]Which components do you want to test?[/bold]\n\n"
            "  [cyan]1)[/cyan] [green]Layers[/green]       — Remove entire transformer layers one by one\n"
            "  [cyan]2)[/cyan] [green]Attention heads[/green] — Remove individual attention heads\n"
            "  [cyan]3)[/cyan] [green]FFN blocks[/green]    — Remove feed-forward networks\n"
            "  [cyan]4)[/cyan] [green]Embeddings[/green]    — Zero-out chunks of embedding dimensions\n"
            "  [cyan]5)[/cyan] [green]All of the above[/green]\n",
            title="What to Ablate",
        )
    )

    choice = Prompt.ask("  Your choice", choices=["1", "2", "3", "4", "5"], default="5")

    mapping = {
        "1": [{"name": "layer_removal", "params": {}}],
        "2": [{"name": "head_pruning", "params": {}}],
        "3": [{"name": "ffn_ablation", "params": {}}],
        "4": [{"name": "embedding_ablation", "params": {"chunk_size": 48}}],
        "5": [
            {"name": "layer_removal", "params": {}},
            {"name": "head_pruning", "params": {}},
            {"name": "ffn_ablation", "params": {}},
            {"name": "embedding_ablation", "params": {"chunk_size": 48}},
        ],
    }
    return mapping[choice]


def _pick_sample_size() -> int:
    """Let the user pick how many samples to evaluate on (custom mode)."""
    console.print()
    console.print(
        Panel(
            "[bold]How thorough should the evaluation be?[/bold]\n\n"
            "  [cyan]1)[/cyan] [green]Quick[/green]     — 25 samples  (fast, rough estimate)\n"
            "  [cyan]2)[/cyan] [green]Standard[/green]  — 100 samples (good balance)\n"
            "  [cyan]3)[/cyan] [green]Thorough[/green]  — 500 samples (slower, more accurate)\n",
            title="Evaluation Depth",
        )
    )

    choice = Prompt.ask("  Your choice", choices=["1", "2", "3"], default="2")
    return {"1": 25, "2": 100, "3": 500}[choice]


def run_interactive():
    """Main interactive flow — walks the user through setting up and running an ablation."""
    console.print()
    console.print(
        Panel.fit(
            "[bold white on blue]  OBLITERATUS — Master Ablation Suite  [/bold white on blue]\n\n"
            "This tool helps you understand which parts of an AI model\n"
            "are most important by systematically removing components\n"
            "and measuring the impact on performance.\n\n"
            "[dim]No coding required — just answer a few questions.[/dim]",
        )
    )

    # Step 1: Hardware
    tier = _pick_compute_tier()
    console.print(f"\n  [bold]Selected tier:[/bold] {tier.upper()}")

    # Step 2: Model
    model_preset = _pick_model(tier)
    console.print(f"\n  [bold]Selected model:[/bold] {model_preset.name} ({model_preset.hf_id})")

    # Step 3: Study preset OR custom strategies + sample size
    study_preset = _pick_study_preset()

    if study_preset is not None:
        console.print(f"\n  [bold]Preset:[/bold] {study_preset.name}")
        strategies = study_preset.strategies
        max_samples = study_preset.max_samples
        batch_size = study_preset.batch_size
        max_length = study_preset.max_length
    else:
        strategies = _pick_strategies()
        max_samples = _pick_sample_size()
        batch_size = 4 if tier in ("tiny", "small") else 8
        max_length = 256

    strategy_names = [s["name"] for s in strategies]
    console.print(f"  [bold]Strategies:[/bold] {', '.join(strategy_names)}")

    # Step 4: Determine device and dtype
    device = "cpu"
    dtype = model_preset.recommended_dtype
    quantization = None
    try:
        import torch

        if torch.cuda.is_available():
            device = "auto"
        elif hasattr(torch.backends, "mps") and torch.backends.mps.is_available():
            device = "mps"
    except ImportError:
        pass

    if model_preset.recommended_quantization and device != "cpu":
        if Confirm.ask(
            f"\n  Use {model_preset.recommended_quantization} quantization? (saves memory)",
            default=True,
        ):
            quantization = model_preset.recommended_quantization

    # Build config
    from obliteratus.config import StudyConfig, ModelConfig, DatasetConfig, StrategyConfig

    model_cfg = ModelConfig(
        name=model_preset.hf_id,
        task="causal_lm",
        dtype=dtype,
        device=device,
        trust_remote_code=True,
    )

    dataset_cfg = DatasetConfig(
        name="wikitext",
        subset="wikitext-2-raw-v1",
        split="test",
        text_column="text",
        max_samples=max_samples,
    )

    strategy_cfgs = [StrategyConfig(name=s["name"], params=s.get("params", {})) for s in strategies]

    config = StudyConfig(
        model=model_cfg,
        dataset=dataset_cfg,
        strategies=strategy_cfgs,
        metrics=["perplexity"],
        batch_size=batch_size,
        max_length=max_length,
        output_dir=f"results/{model_preset.hf_id.replace('/', '_')}",
    )

    # Confirmation
    preset_label = f" (preset: {study_preset.name})" if study_preset else " (custom)"
    console.print()
    console.print(Panel(
        f"[bold]Model:[/bold]       {model_preset.name} ({model_preset.hf_id})\n"
        f"[bold]Device:[/bold]      {device} ({dtype})"
        + (f" + {quantization}" if quantization else "")
        + f"\n[bold]Dataset:[/bold]     wikitext-2 ({max_samples} samples)\n"
        f"[bold]Ablation:[/bold]    {', '.join(strategy_names)}{preset_label}\n"
        f"[bold]Output:[/bold]      {config.output_dir}/",
        title="Run Configuration",
    ))

    if not Confirm.ask("\n  Ready to start?", default=True):
        console.print("[yellow]Cancelled.[/yellow]")
        return None

    # Handle quantization by modifying the loader
    if quantization:
        _run_quantized(config, quantization)
    else:
        from obliteratus.runner import run_study
        return run_study(config)


def _run_quantized(config, quantization: str):
    """Run ablation with quantized model loading."""
    from obliteratus.runner import run_study

    # Patch the model loading to use bitsandbytes quantization
    console.print(f"\n[bold yellow]Note:[/bold yellow] Loading with {quantization} quantization...")
    console.print("  Make sure 'bitsandbytes' is installed: pip install bitsandbytes\n")

    # For quantized models, we modify the config device to auto (needed for bitsandbytes)
    config.model.device = "auto"
    config.model.quantization = quantization
    return run_study(config)