#!/usr/bin/env python3
import argparse
import json
from pathlib import Path

import matplotlib.pyplot as plt
import numpy as np


def load_json(path):
    with open(path, "r", encoding="utf-8") as f:
        return json.load(f)


def main():
    parser = argparse.ArgumentParser(description="Plot predictor test metrics from test_results.json.")
    parser.add_argument("--test_results", required=True)
    parser.add_argument("--output_dir", required=True)
    args = parser.parse_args()

    metrics = load_json(args.test_results)
    output_dir = Path(args.output_dir)
    output_dir.mkdir(parents=True, exist_ok=True)

    labels = ["label_0", "label_1", "overall"]
    pearson = [
        metrics.get("test_pearson_label_0", np.nan),
        metrics.get("test_pearson_label_1", np.nan),
        metrics.get("test_pearson", np.nan),
    ]
    r2 = [
        metrics.get("test_r2_label_0", np.nan),
        metrics.get("test_r2_label_1", np.nan),
        metrics.get("test_r2", np.nan),
    ]
    mae = [
        metrics.get("test_mae_label_0", np.nan),
        metrics.get("test_mae_label_1", np.nan),
        metrics.get("test_mae", np.nan),
    ]

    fig, axes = plt.subplots(1, 3, figsize=(12, 3.8))
    for ax, values, title in zip(axes, [pearson, r2, mae], ["Pearson", "R2", "MAE"]):
        ax.bar(labels, values, color=["#3b82f6", "#10b981", "#6366f1"])
        ax.set_title(title)
        ax.tick_params(axis="x", rotation=20)
        for i, v in enumerate(values):
            if np.isfinite(v):
                ax.text(i, v, f"{v:.3f}", ha="center", va="bottom", fontsize=9)
    fig.tight_layout()
    out = output_dir / "predictor_metrics.png"
    fig.savefig(out, dpi=220, bbox_inches="tight")
    print(out)


if __name__ == "__main__":
    main()