import tkinter as tk from tkinter import messagebox

---------------- RULE BASE ----------------

rules = [ (["fever", "cough"], "flu"), (["fever", "rash"], "measles"), (["headache", "fever"], "viral infection"), (["flu", "body_pain"], "severe flu"), (["cough", "chest_pain"], "bronchitis") ]

---------------- FORWARD CHAINING ENGINE ----------------

def forward_chaining(facts):

inferred = set(facts)
log = []
added = True

while added:
    added = False

    for condition, result in rules:
        if all(c in inferred for c in condition) and result not in inferred:

            inferred.add(result)
            log.append(f"Rule Applied: IF {condition} THEN {result}")
            added = True

return inferred, log

---------------- RUN EXPERT SYSTEM ----------------

def run_system():

selected = []

for symptom, var in symptom_vars.items():
    if var.get():
        selected.append(symptom)

if not selected:
    messagebox.showwarning("Warning", "Select at least one symptom")
    return

results, reasoning = forward_chaining(selected)

result_box.delete("1.0", tk.END)

result_box.insert(tk.END, "Selected Symptoms:\n")
result_box.insert(tk.END, str(selected) + "\n\n")

result_box.insert(tk.END, "Inference Steps:\n")
for step in reasoning:
    result_box.insert(tk.END, step + "\n")

result_box.insert(tk.END, "\nFinal Knowledge Base:\n")
result_box.insert(tk.END, str(results))

---------------- UI DESIGN ----------------

root = tk.Tk() root.title("Rule Based Expert System") root.geometry("600x550") root.configure(bg="#1e1e2f")

title = tk.Label( root, text="AI Rule Based Expert System", font=("Arial", 20, "bold"), fg="white", bg="#1e1e2f" ) title.pack(pady=15)

frame = tk.Frame(root, bg="#2c2c3c", padx=20, pady=20) frame.pack(pady=10)

symptoms = [ "fever", "cough", "rash", "headache", "body_pain", "chest_pain" ]

symptom_vars = {}

tk.Label( frame, text="Select Symptoms", font=("Arial", 14, "bold"), bg="#2c2c3c", fg="white" ).pack()

for s in symptoms: var = tk.BooleanVar() symptom_vars[s] = var

cb = tk.Checkbutton(
    frame,
    text=s,
    variable=var,
    font=("Arial", 11),
    bg="#2c2c3c",
    fg="white",
    selectcolor="#444"
)

cb.pack(anchor="w")

run_btn = tk.Button( root, text="Run Expert System", font=("Arial", 12, "bold"), bg="#00adb5", fg="white", command=run_system )

run_btn.pack(pady=10)

result_box = tk.Text( root, height=15, width=65, bg="#111", fg="#00ff9f", font=("Consolas", 10) )

result_box.pack(pady=10)

root.mainloop()