import os
from pathlib import Path
import sys

os.environ.setdefault("MPLCONFIGDIR", "/tmp/matplotlib")

import matplotlib.pyplot as plt
import numpy as np
from matplotlib.ticker import AutoMinorLocator

FONT_NAME = "LXGW WenKai"
BG_COLOR = "white"
GRID_MAJOR = "#111111"
GRID_MINOR = "#8a8a8a"
LINE_COLOR = "#111111"
POINT_COLOR = "#111111"

LOAD_RESISTANCE_OHM = np.array(
    [888.43, 788.46, 625.00, 534.84, 468.16, 494.69, 439.93, 415.40],
    dtype=float,
)
POWER_MW = np.array(
    [130.07, 133.25, 136.90, 143.15, 142.23, 142.29, 142.22, 141.25],
    dtype=float,
)

DEFAULT_OUTPUT = (
    Path(__file__).resolve().parent.parent / "image" / "exp5" / "power_load_curve.svg"
)


def draw_curve(save_path=DEFAULT_OUTPUT):
    save_path = Path(save_path)
    save_path.parent.mkdir(parents=True, exist_ok=True)

    plt.rcParams["font.family"] = FONT_NAME
    plt.rcParams["axes.unicode_minus"] = False

    order = np.argsort(LOAD_RESISTANCE_OHM)
    x = LOAD_RESISTANCE_OHM[order]
    y = POWER_MW[order]

    fig, ax = plt.subplots(figsize=(8.2, 6.0), dpi=160)
    fig.patch.set_facecolor(BG_COLOR)
    ax.set_facecolor(BG_COLOR)

    ax.plot(
        x,
        y,
        color=LINE_COLOR,
        linewidth=2.2,
        zorder=2,
    )
    ax.scatter(
        x,
        y,
        s=55,
        color=POINT_COLOR,
        edgecolors="white",
        linewidths=0.8,
        zorder=3,
    )

    ax.set_xlabel("负载电阻 R_L / Ω", fontsize=13)
    ax.set_ylabel("负载功率 P / mW", fontsize=13)

    ax.set_xlim(400, 900)
    ax.set_ylim(129, 144)
    ax.set_xticks(np.arange(400, 901, 100))
    ax.set_yticks(np.arange(130, 145, 2))
    ax.xaxis.set_minor_locator(AutoMinorLocator(2))
    ax.yaxis.set_minor_locator(AutoMinorLocator(2))
    ax.set_box_aspect(6 / 5)

    ax.grid(True, which="major", color=GRID_MAJOR, linewidth=0.95, alpha=0.9)
    ax.grid(True, which="minor", color=GRID_MINOR, linewidth=0.55, alpha=0.8)

    for spine in ax.spines.values():
        spine.set_linewidth(1.0)
        spine.set_color("#111111")

    fig.tight_layout()
    fig.savefig(save_path, bbox_inches="tight")
    plt.close(fig)
    print(f"saved to: {save_path}")


if __name__ == "__main__":
    output_path = sys.argv[1] if len(sys.argv) > 1 else DEFAULT_OUTPUT
    draw_curve(output_path)