IntCode Processor Input/Output changes

For day 5, ask the user for input

2019/day05/main.go

@@ -1,7 +1,9 @@
 package main
 
 import (
+	"bufio"
 	"fmt"
+	"io/ioutil"
 	"os"
 	"strings"
 	"time"
@@ -11,23 +13,46 @@ import (
 )
 
 func main() {
-	inp := helpers.StdinToString()
+	progFileName := "input"
+	if len(os.Args) > 1 {
+		progFileName = os.Args[1]
+	}
+	dat, err := ioutil.ReadFile(progFileName)
+	if err != nil {
+		fmt.Println("Error reading program file:", err.Error())
+		os.Exit(1)
+	}
 	var prog []int
-	for _, v := range strings.Split(inp, ",") {
+	stringDat := strings.TrimSpace(string(dat))
+	for _, v := range strings.Split(stringDat, ",") {
 		prog = append(prog, helpers.Atoi(v))
 	}
+	fmt.Println("Day 5, part 1: Input '1'")
+	fmt.Println("Day 5, part 2: Input '5'")
 	p := intcode.NewProgram(prog)
 	go p.Run()
-	// Part 1:
-	// p.Input() <- 1
-	// Part 2:
-	p.Input() <- 5
 	go func() {
 		for {
-			out := <-p.Output()
-			fmt.Println(out)
-			if p.State() != intcode.RET_OK {
-				os.Exit(0)
+			if st := p.State(); st != intcode.RET_OK {
+				if st == intcode.RET_ERR {
+					os.Exit(1)
+				} else {
+					os.Exit(0)
+				}
+			}
+			if p.NeedsInput() {
+				fmt.Print("Requesting Input: ")
+				reader := bufio.NewReader(os.Stdin)
+				inp, err := reader.ReadString('\n')
+				if err != nil {
+					fmt.Println("Input Error:", err.Error())
+				} else {
+					p.Input(helpers.Atoi(strings.TrimSpace(inp)))
+				}
+			}
+			if p.NeedsOutput() {
+				out := p.Output()
+				fmt.Println(out)
 			}
 			time.Sleep(50)
 		}