app [main!] { pf: platform "../platform/main.roc" }

import pf.Stdout
import pf.AllocHost

main! : List(Str) => Try({}, [Exit(I32)])
main! = |_args| {
    Stdout.line!("Testing poke/peek with Try-based alloc...")

    # Allocate 4 bytes - returns [Ok(U64), OutOfMemory]
    alloc_result = AllocHost.alloc_impl!(4)

    match alloc_result {
        OutOfMemory => {
            Stdout.line!("Allocation failed: OutOfMemory")
            Err(Exit(1))
        }

        Ok(ptr) => {
            Stdout.line!("Allocated 4 bytes.")

            # Write "Roc!" using poke
            AllocHost.poke_impl!({ byte: 82, ptr: ptr })
            AllocHost.poke_impl!({ byte: 111, ptr: ptr + 1 })
            AllocHost.poke_impl!({ byte: 99, ptr: ptr + 2 })
            AllocHost.poke_impl!({ byte: 33, ptr: ptr + 3 })

            Stdout.line!("Written 'Roc!' to memory.")

            # Read back using peek
            c1 = AllocHost.peek_impl!(ptr)
            c2 = AllocHost.peek_impl!(ptr + 1)
            c3 = AllocHost.peek_impl!(ptr + 2)
            c4 = AllocHost.peek_impl!(ptr + 3)

            Stdout.line!("Read back: ${Str.inspect(c1)} ${Str.inspect(c2)} ${Str.inspect(c3)} ${Str.inspect(c4)}")

            # Expected: 82 111 99 33 = "Roc!"
            Stdout.line!("Expected:  82 111 99 33")

            # Deallocate
            AllocHost.dealloc_impl!(ptr)
            Stdout.line!("Deallocated. SUCCESS!")
            Ok({})
        }
    }
}