open Utilities.Aliases

type output = { output: string; error: string; status: string; }

let handle_exit_status (status: Unix.process_status): string =
    match status with
    | Unix.WEXITED n -> "Exit " ^ str_int n
    | Unix.WSIGNALED n -> "Kill " ^ str_int n
    | Unix.WSTOPPED n -> "Stopped " ^ str_int n

let read (env: string array) (command: string): output =

    let stdout, stdin, stderr = Unix.open_process_full command env in
    let in_buffer = Buffer.create 4096 in
    let err_buffer = Buffer.create 4096 in

    let rec read_in () =
        let in_line = input_line stdout in
        Buffer.add_string in_buffer in_line;
        Buffer.add_char in_buffer '\n';
        read_in ()
    in
    try read_in () with End_of_file -> ();

    let rec read_err () =
        let err_line = input_line stderr in
        Buffer.add_string err_buffer err_line;
        Buffer.add_char err_buffer '\n';
        read_err ()
    in
    try read_err () with
        End_of_file -> let exit_status =
            handle_exit_status (Unix.close_process_full (stdout, stdin, stderr))
        in
        {
            output = String.trim (Buffer.contents in_buffer);
            error = Buffer.contents err_buffer;
            status = exit_status;
        }

let format (output: output): string =
    match output with
    | { output = o; error = _; status = "Exit 0" } -> o
    | { output = ""; error = e; status = s } -> "[" ^ s ^ "]" ^ " " ^ e
    | { output = o; error = _; status = s } -> "[" ^ s ^ "]" ^ " " ^ o