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)
 		}

2019/intcode-processor/processor.go

@@ -6,11 +6,6 @@ import (
 	"math"
 )
 
-const (
-	MODE_POS = iota
-	MODE_IMM
-)
-
 const (
 	OP_ADD = 1
 	OP_MLT = 2
@@ -23,6 +18,11 @@ const (
 	OP_EXT = 99
 )
 
+const (
+	MODE_POS = iota
+	MODE_IMM
+)
+
 const (
 	RET_ERR = iota - 1
 	RET_OK
@@ -36,15 +36,17 @@ type Program struct {
 	state int
 	error error
 
-	input  chan int
-	output chan int
+	waitingForInput  bool
+	input            chan int
+	waitingForOutput bool
+	output           chan int
 }
 
 func NewProgram(prog []int) *Program {
 	p := new(Program)
 	p.code = make([]int, len(prog))
-	p.input = make(chan int, 2)
-	p.output = make(chan int, 2)
+	p.input = make(chan int)
+	p.output = make(chan int)
 	copy(p.code, prog)
 	return p
 }
@@ -157,6 +159,14 @@ func (p *Program) SetProgramValueAt(idx, val int) {
 	p.code[idx] = val
 }
 
+func (p *Program) NeedsInput() bool {
+	return p.waitingForInput
+}
+
+func (p *Program) NeedsOutput() bool {
+	return p.waitingForOutput
+}
+
 func (p *Program) opCode(intcode int) int {
 	return intcode % 100
 }
@@ -188,12 +198,15 @@ func (p *Program) get(mode, v int) int {
 	return v
 }
 
-func (p *Program) Input() chan int {
-	return p.input
+func (p *Program) Input(v int) {
+	p.input <- v
+	p.waitingForInput = false
 }
 
-func (p *Program) Output() chan int {
-	return p.output
+func (p *Program) Output() int {
+	v := <-p.output
+	p.waitingForOutput = false
+	return v
 }
 
 func (p *Program) opAdd(intcode, a1, a2, dest int) {
@@ -220,12 +233,15 @@ func (p *Program) opInp(intcode, dest int) {
 		p.error = errors.New("Invalid Destination Mode")
 		p.state = RET_ERR
 	}
+	p.waitingForInput = true
 	p.code[dest] = <-p.input
+	p.waitingForInput = false
 }
 
 func (p *Program) opOut(intcode, val int) {
 	valmd := p.paramMode(intcode, 0)
 	ret := p.get(valmd, val)
+	p.waitingForOutput = true
 	p.output <- ret
 }