import os
import matplotlib.pyplot as plt

def plot_speed(log_path="output_this_run/simulation_time.log", output_png="output_this_run/simulation_speed.png"):
    if not os.path.exists(log_path):
        print(f"{log_path} not found.")
        return

    times = []
    voltages = []
    
    cumulative_time = 0.0

    with open(log_path, "r") as f:
        lines = f.readlines()
        
    for line in lines:
        if "Time" in line and "Voltage(V)" in line:
            continue
        parts = line.split()
        if len(parts) >= 6:
            try:
                # Format: Time, Voltage(V), Step(V), Current(A), Iterations, TimeTaken(s)
                voltage = float(parts[1])
                time_taken = float(parts[5])
                cumulative_time += time_taken
                
                times.append(cumulative_time)
                voltages.append(voltage)
            except ValueError:
                continue

    if not times:
        print("No valid data found in log.")
        return

    plt.figure(figsize=(10, 6))
    plt.plot(times, voltages, marker='o', linestyle='-')
    plt.xlabel("Cumulative Simulation Time (s)")
    plt.ylabel("Voltage (V)")
    plt.title("Simulation Voltage over Time")
    plt.grid(True)
    plt.savefig(output_png, dpi=300)
    print(f"Plot saved to {output_png}")

if __name__ == "__main__":
    import sys
    log_file = sys.argv[1] if len(sys.argv) > 1 else "output_this_run/simulation_time.log"
    out_file = sys.argv[2] if len(sys.argv) > 2 else "output_this_run/simulation_speed.png"
    plot_speed(log_file, out_file)