#!/usr/bin/env python3
"""Visualize cell-eval comparison: Prompt Selection vs Random Baseline.

Modes:
  --perturbation X  : Single perturbation bar chart
  --all             : Heatmap across all perturbations
"""
from __future__ import annotations

import argparse
import sys
from pathlib import Path

_THIS_DIR = Path(__file__).resolve().parent
if str(_THIS_DIR.parent) not in sys.path:
    sys.path.insert(0, str(_THIS_DIR.parent))

import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt
import numpy as np
import pandas as pd

from prompt_selection import config as cfg

# Metrics to exclude (uninformative: all zero, NaN, or identical)
EXCLUDE = {
    "overlap_at_50", "overlap_at_100", "overlap_at_200",
    "precision_at_50", "precision_at_100", "precision_at_200",
    "de_spearman_sig",
    "discrimination_score_l1", "discrimination_score_l2", "discrimination_score_cosine",
    "de_nsig_counts_real", "de_nsig_counts_pred",
}

DISPLAY_NAMES = {
    "overlap_at_N": "Overlap@N",
    "overlap_at_500": "Overlap@500",
    "precision_at_N": "Precision@N",
    "precision_at_500": "Precision@500",
    "de_direction_match": "DE Direction\nMatch",
    "de_spearman_lfc_sig": "DE Spearman\nLFC",
    "de_sig_genes_recall": "DE Sig Genes\nRecall",
    "pr_auc": "PR AUC",
    "roc_auc": "ROC AUC",
    "pearson_delta": "Pearson\nDelta",
    "mse": "MSE",
    "mae": "MAE",
    "mse_delta": "MSE Delta",
    "mae_delta": "MAE Delta",
}

LOWER_IS_BETTER = {"mse", "mae", "mse_delta", "mae_delta"}


def visualize_single(pert_name: str):
    """Generate bar chart for a single perturbation."""
    pcfg = cfg.get_pert_config(pert_name)
    csv_path = pcfg.eval_dir / "comparison_mean.csv"
    output_path = pcfg.eval_dir / "comparison_chart.png"

    if not csv_path.exists():
        print(f"No comparison_mean.csv found for {pert_name}: {csv_path}")
        return

    df = pd.read_csv(csv_path)
    df = df[~df["metric"].isin(EXCLUDE)].copy()
    df = df.dropna(subset=["prompt_selection", "random_baseline"]).reset_index(drop=True)
    df["display"] = df["metric"].map(DISPLAY_NAMES).fillna(df["metric"])
    df["pct_diff"] = np.where(
        df["random_baseline"].abs() > 1e-12,
        (df["prompt_selection"] - df["random_baseline"]) / df["random_baseline"].abs() * 100,
        0.0,
    )

    error_metrics = df[df["metric"].isin(LOWER_IS_BETTER)].reset_index(drop=True)
    quality_metrics = df[~df["metric"].isin(LOWER_IS_BETTER)].reset_index(drop=True)

    fig, axes = plt.subplots(
        2, 1, figsize=(14, 10),
        gridspec_kw={"height_ratios": [max(len(quality_metrics), 1), max(len(error_metrics), 1)]},
    )
    fig.suptitle(
        f"Cell-Eval: Prompt Selection vs Random Baseline ({pert_name} B-cells)",
        fontsize=15, fontweight="bold", y=0.98,
    )

    colors_ps = "#4C72B0"
    colors_bl = "#DD8452"

    for ax, subset, title, lower_better in [
        (axes[0], quality_metrics, "Quality Metrics (higher is better)", False),
        (axes[1], error_metrics, "Error Metrics (lower is better)", True),
    ]:
        n = len(subset)
        if n == 0:
            ax.set_visible(False)
            continue

        y = np.arange(n)
        bar_h = 0.35

        ax.barh(y - bar_h / 2, subset["prompt_selection"], bar_h,
                label="Prompt Selection", color=colors_ps, edgecolor="white", linewidth=0.5)
        ax.barh(y + bar_h / 2, subset["random_baseline"], bar_h,
                label="Random Baseline", color=colors_bl, edgecolor="white", linewidth=0.5)

        ax.set_yticks(y)
        ax.set_yticklabels(subset["display"], fontsize=11)
        ax.invert_yaxis()
        ax.set_title(title, fontsize=12, fontweight="bold", pad=10)
        ax.legend(loc="lower right", fontsize=10)
        ax.grid(axis="x", alpha=0.3, linestyle="--")
        ax.set_axisbelow(True)

        for i, row in subset.iterrows():
            idx = subset.index.get_loc(i)
            pct = row["pct_diff"]
            max_val = max(row["prompt_selection"], row["random_baseline"])
            if abs(pct) < 0.01:
                label = "0%"
                color = "gray"
            else:
                sign = "+" if pct > 0 else ""
                label = f"{sign}{pct:.1f}%"
                if lower_better:
                    color = "#D32F2F" if pct > 0 else "#388E3C"
                else:
                    color = "#388E3C" if pct > 0 else "#D32F2F"
            ax.text(max_val * 1.02, idx, label,
                    va="center", ha="left", fontsize=10, fontweight="bold", color=color)

        x_max = subset[["prompt_selection", "random_baseline"]].max().max()
        ax.set_xlim(right=x_max * 1.18)

    plt.tight_layout(rect=[0, 0, 1, 0.96])
    fig.savefig(output_path, dpi=150, bbox_inches="tight", facecolor="white")
    print(f"Saved: {output_path}")


def visualize_all():
    """Generate heatmap across all perturbations."""
    csv_path = cfg.EVAL_DIR / "all_comparison.csv"
    output_path = cfg.EVAL_DIR / "all_comparison_heatmap.png"

    if not csv_path.exists():
        print(f"No all_comparison.csv found: {csv_path}")
        print("Run aggregate_results.py first.")
        return

    df = pd.read_csv(csv_path)
    df = df[~df["metric"].isin(EXCLUDE)].copy()
    df = df.dropna(subset=["prompt_selection", "random_baseline"])

    # Compute percentage difference
    df["pct_diff"] = np.where(
        df["random_baseline"].abs() > 1e-12,
        (df["prompt_selection"] - df["random_baseline"]) / df["random_baseline"].abs() * 100,
        0.0,
    )

    # For lower-is-better metrics, negate so positive = PS better
    for m in LOWER_IS_BETTER:
        mask = df["metric"] == m
        df.loc[mask, "pct_diff"] = -df.loc[mask, "pct_diff"]

    df["display"] = df["metric"].map(DISPLAY_NAMES).fillna(df["metric"])

    # Pivot: perturbation × metric
    pivot = df.pivot_table(index="perturbation", columns="display", values="pct_diff", aggfunc="first")
    pivot = pivot.reindex(sorted(pivot.index))

    fig, ax = plt.subplots(figsize=(16, max(8, len(pivot) * 0.6)))
    vmax = max(abs(pivot.values[~np.isnan(pivot.values)].min()), abs(pivot.values[~np.isnan(pivot.values)].max()), 10)
    im = ax.imshow(pivot.values, cmap="RdYlGn", aspect="auto", vmin=-vmax, vmax=vmax)

    ax.set_xticks(range(len(pivot.columns)))
    ax.set_xticklabels(pivot.columns, rotation=45, ha="right", fontsize=10)
    ax.set_yticks(range(len(pivot.index)))
    ax.set_yticklabels(pivot.index, fontsize=11)

    # Annotate cells
    for i in range(len(pivot.index)):
        for j in range(len(pivot.columns)):
            val = pivot.values[i, j]
            if not np.isnan(val):
                color = "white" if abs(val) > vmax * 0.6 else "black"
                ax.text(j, i, f"{val:+.1f}%", ha="center", va="center",
                        fontsize=8, color=color, fontweight="bold")

    cbar = plt.colorbar(im, ax=ax, shrink=0.8, pad=0.02)
    cbar.set_label("% Difference (positive = PS better)", fontsize=11)

    ax.set_title(
        "Prompt Selection vs Random Baseline: % Improvement per Perturbation\n"
        "(green = PS better, red = Baseline better; error metrics negated)",
        fontsize=13, fontweight="bold", pad=15,
    )

    plt.tight_layout()
    fig.savefig(output_path, dpi=150, bbox_inches="tight", facecolor="white")
    print(f"Saved: {output_path}")


def main():
    parser = argparse.ArgumentParser(description="Visualize cell-eval comparison results")
    group = parser.add_mutually_exclusive_group(required=True)
    group.add_argument("--perturbation", type=str, help="Single perturbation name")
    group.add_argument("--all", action="store_true", help="All perturbations heatmap")
    args = parser.parse_args()

    if args.all:
        visualize_all()
    else:
        visualize_single(args.perturbation)


if __name__ == "__main__":
    main()