import gradio as gr
import subprocess, tempfile, os, resource, shutil


# ------------------------------------------------------------------
# 1️⃣  Función que compila y ejecuta el código C
# ------------------------------------------------------------------
def compile_and_run(code: str, stdin: str = "") -> str:
    """
    Compila el código C recibido, lo ejecuta con límites de
    recursos y devuelve stdout, stderr y exit-code.
    """
    tmpdir   = tempfile.mkdtemp(prefix="c_exec_")
    c_path   = os.path.join(tmpdir, "main.c")
    bin_path = os.path.join(tmpdir, "main")

    # Guardar el código fuente
    with open(c_path, "w") as f:
        f.write(code)

    # Compilar
    compile_proc = subprocess.run(
        ["gcc", c_path, "-O2", "-std=c11", "-pipe", "-o", bin_path],
        capture_output=True,
        text=True,
        timeout=10
    )
    if compile_proc.returncode != 0:
        shutil.rmtree(tmpdir, ignore_errors=True)
        return f"❌ Error de compilación:\n{compile_proc.stderr}"

    # Límites (CPU 2 s, RAM 128 MB)
    def limit_resources():
        resource.setrlimit(resource.RLIMIT_CPU, (2, 2))
        resource.setrlimit(resource.RLIMIT_AS, (128 * 1024 * 1024,
                                               128 * 1024 * 1024))

    try:
        run_proc = subprocess.run(
            [bin_path],
            input=stdin,
            text=True,
            capture_output=True,
            timeout=2,
            preexec_fn=limit_resources
        )
    except subprocess.TimeoutExpired:
        shutil.rmtree(tmpdir, ignore_errors=True)
        return "⏰ Tiempo de ejecución excedido (2 s)."

    stdout, stderr = run_proc.stdout, run_proc.stderr
    exit_code = run_proc.returncode

    shutil.rmtree(tmpdir, ignore_errors=True)

    result = f"⏹ Código de salida: {exit_code}\n"
    if stdout:
        result += f"\n📤 STDOUT\n{stdout}"
    if stderr:
        result += f"\n⚠️ STDERR\n{stderr}"
    return result.strip()


# ------------------------------------------------------------------
# 2️⃣  Detección automática del lenguaje para gr.Code
#      ('c' en Gradio ≥4, 'cpp' en Gradio 3)
# ------------------------------------------------------------------
def detect_c_language() -> str:
    langs = getattr(gr.Code, "languages", [])
    return "c" if "c" in langs else "cpp"

code_lang = detect_c_language()


# ------------------------------------------------------------------
# 3️⃣  Construcción de la interfaz
# ------------------------------------------------------------------
title       = "Compilador C online (42 Edition)"
description = (
    "Ejecuta fragmentos de **lenguaje C** con límite de recursos.\n"
    "Disponible también como endpoint REST (`/run/predict`)."
)

demo = gr.Interface(
    fn=compile_and_run,
    inputs=[
        gr.Code(language=code_lang, label="Código C"),
        gr.Textbox(
            lines=3,
            placeholder="Entrada estándar (stdin)",
            label="Stdin (opcional)"
        ),
    ],
    outputs=gr.Textbox(label="Resultado"),
    title=title,
    description=description,
    examples=[
        ["#include <stdio.h>\nint main(){puts(\"Hola 42!\");}", ""],
        ["#include <stdio.h>\nint main(){int a,b;scanf(\"%d %d\",&a,&b);"
         "printf(\"%d\\n\",a+b);}", "3 4"],
    ],
)

if __name__ == "__main__":
    demo.launch()