#!/usr/bin/env python3
# vim:tabstop=4 softtabstop=4 shiftwidth=4 textwidth=160 smarttab expandtab colorcolumn=160
#
# Copyright (C) 2023 Daniel Friesel
#
# SPDX-License-Identifier: GPL-2.0-or-later

from matplotlib import cm
import matplotlib.pyplot as plt
import numpy as np
import sys

matplotlib_theme = "fast"


def parse_file(filename, in_channel, out_channel):
    readings = list()
    with open(filename, "r") as f:
        for line in f:
            if line.startswith("#"):
                continue
            timestamp, channel, voltage = line.split()
            timestamp = float(timestamp)
            channel = int(channel)
            voltage = float(voltage)
            if abs(voltage) > 1:
                readings.append((timestamp, channel, voltage))
    vin_t = list()
    vout_t = list()
    vout_vin = list()

    last_vin = None
    last_vout = None
    for timestamp, channel, voltage in readings:
        if channel == in_channel:
            vin_t.append((timestamp, voltage))
            if last_vin is not None and last_vout is not None:
                vout_vin.append((np.mean((last_vin, voltage)), last_vout))
            last_vin = voltage
        elif channel == out_channel:
            vout_t.append((timestamp, voltage))
            if last_vin is not None and last_vout is not None:
                vout_vin.append((last_vin, np.mean((last_vout, voltage))))
            last_vout = voltage

    return np.array(vin_t), np.array(vout_t), np.array(vout_vin)


def main(files):
    plt.style.use(matplotlib_theme)
    handles = list()
    cmap = cm.get_cmap("winter")
    in_channel = int(files.pop(0))
    out_channel = int(files.pop(0))
    for i, pair in enumerate(files):
        current, filename = pair.split("=")
        vin_t, vout_t, vout_vin = parse_file(filename, in_channel, out_channel)
        (handle,) = plt.plot(
            vout_vin[:, 0],
            vout_vin[:, 1],
            linestyle="none",
            marker="s",
            color=cmap(i / len(files)),
            markersize=2,
            label=current,
        )
        handles.append(handle)

    plt.legend(handles=handles, title="Output Current [mA]")
    plt.title("MT3608 Output Voltage Stability")
    plt.xlabel("Input Voltage [V]")
    plt.ylabel("Output Voltage [V]")
    plt.show()


if __name__ == "__main__":
    main(sys.argv[1:])