// Demonstrating resumable effect handlers in Lux
//
// Handlers can use `resume(value)` to return a value to the effect call site
// and continue the computation. This enables powerful control flow patterns.
//
// Expected output:
// [INFO] Starting computation
// [DEBUG] Intermediate result: 10
// [INFO] Computation complete
// Final result: 20

// Define a custom logging effect
effect Logger {
    fn log(level: String, msg: String): Unit
    fn getLogLevel(): String
}

// A function that uses the Logger effect
fn compute(): Int with {Logger} = {
    Logger.log("INFO", "Starting computation")
    let x = 10
    Logger.log("DEBUG", "Intermediate result: " + toString(x))
    let result = x * 2
    Logger.log("INFO", "Computation complete")
    result
}

// A handler that prints logs with brackets and resumes with Unit
handler prettyLogger: Logger {
    fn log(level, msg) = {
        Console.print("[" + level + "] " + msg)
        resume(())
    }
    fn getLogLevel() = resume("DEBUG")
}

// Main function
fn main(): Unit with {Console} = {
    let result = run compute() with {
        Logger = prettyLogger
    }
    Console.print("Final result: " + toString(result))
}

let output = run main() with {}