import numpy as np
import matplotlib.pyplot as plt

def stress_analysis(force, die_width, die_height, material_strength, temperature_change=50, alpha=1e-5, elastic_modulus=200000, fatigue_strength=150):
    try:
        stress = force / (die_width * die_height)
        safety_factor = material_strength / stress
        thermal_stress = elastic_modulus * alpha * temperature_change
        fatigue_stress = fatigue_strength

        x = np.linspace(1, 100, 100)
        stress_curve = stress * x / 100
        material_strength_curve = np.full_like(x, material_strength)
        safety_factor_curve = material_strength_curve / stress_curve
        thermal_stress_curve = np.full_like(x, thermal_stress)
        fatigue_strength_curve = np.full_like(x, fatigue_stress)

        fig, ax = plt.subplots(figsize=(10, 6))
        ax.plot(x, stress_curve, label="Stress (σ)", color="blue")
        ax.plot(x, material_strength_curve, label="Material Strength (σ_y)", color="green")
        ax.plot(x, safety_factor_curve, label="Safety Factor (SF)", color="orange")
        ax.plot(x, thermal_stress_curve, label="Thermal Stress (σ_thermal)", color="purple")
        ax.plot(x, fatigue_strength_curve, label="Fatigue Strength (σ_fatigue)", color="brown")
        ax.axhline(1, color="red", linestyle="--", label="Critical Safety Threshold (SF=1)")

        ax.set_title("Combined Stress Analysis Parameters")
        ax.set_xlabel("Operational Range (%)")
        ax.set_ylabel("Parameter Value (MPa or Unitless)")
        ax.legend()
        ax.grid()

        plt.tight_layout()
        plt.close(fig)

        return f"Safety Factor: {round(safety_factor, 2)}", fig
    except Exception as e:
        return f"Error in stress analysis: {str(e)}", None