From 9f51b5e7d11c8f6e1d16dbe5b5a1d17f6cd2a300 Mon Sep 17 00:00:00 2001
From: Dan Anglin <daangling@gmail.com>
Date: Sat, 29 Oct 2022 23:22:52 +0100
Subject: [PATCH] feat: add move

---
 experiments/go/move/.dockerignore      |  4 ++
 experiments/go/move/Dockerfile         | 22 ++++++++++
 experiments/go/move/main.go            | 60 ++++++++++++++++++++++++++
 experiments/go/move/movement_string.go | 27 ++++++++++++
 4 files changed, 113 insertions(+)
 create mode 100644 experiments/go/move/.dockerignore
 create mode 100644 experiments/go/move/Dockerfile
 create mode 100644 experiments/go/move/main.go
 create mode 100644 experiments/go/move/movement_string.go

diff --git a/experiments/go/move/.dockerignore b/experiments/go/move/.dockerignore
new file mode 100644
index 0000000..69804bc
--- /dev/null
+++ b/experiments/go/move/.dockerignore
@@ -0,0 +1,4 @@
+*
+!*.go
+!go.sum
+!go.mod
diff --git a/experiments/go/move/Dockerfile b/experiments/go/move/Dockerfile
new file mode 100644
index 0000000..46b71c6
--- /dev/null
+++ b/experiments/go/move/Dockerfile
@@ -0,0 +1,22 @@
+# Build the application
+FROM docker.io/library/golang:1.19.2-alpine3.16@sha256:46752c2ee3bd8388608e41362964c84f7a6dffe99d86faeddc82d917740c5968 AS builder
+
+ENV GOOS=linux
+ENV GOARCH=amd64
+ENV CGO_ENABLED=0
+
+WORKDIR /build
+
+COPY . .
+
+RUN \
+    go mod tidy \
+    && go build -ldflags="-s -w" -a -o /build/move .
+
+FROM scratch
+
+COPY --from=builder /build/move /move
+
+USER 3000:3000
+
+ENTRYPOINT ["/move"]
diff --git a/experiments/go/move/main.go b/experiments/go/move/main.go
new file mode 100644
index 0000000..04c4aef
--- /dev/null
+++ b/experiments/go/move/main.go
@@ -0,0 +1,60 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+	"errors"
+	"flag"
+	"os"
+)
+
+//go:generate stringer -type=Movement
+type Movement int
+
+const (
+	Unknown Movement = iota
+	Forward
+	Backward
+	Left
+	Right
+)
+
+func newMovement(movement string) (Movement) {
+	switch strings.ToLower(movement) {
+	case "forward":
+		return Forward
+	case "backward":
+		return Backward
+	case "left":
+		return Left
+	case "right":
+		return Right
+	default:
+		return Unknown
+	}
+}
+
+func main() {
+	direction := flag.String("direction", "", "The direction to move.")
+	flag.Parse()
+
+	if err := run(*direction); err != nil {
+		fmt.Printf("Error: %v.\n", err)
+		os.Exit(1)
+	}
+}
+
+func run(direction string) error {
+	if len(direction) == 0 {
+		return errors.New("direction is not set")
+	}
+
+	move := newMovement(direction)
+	if move == Unknown {
+		return errors.New("unknown direction")
+	}
+
+	fmt.Printf("I moved %s.\n", move)
+
+	return nil
+}
diff --git a/experiments/go/move/movement_string.go b/experiments/go/move/movement_string.go
new file mode 100644
index 0000000..c8ec3b1
--- /dev/null
+++ b/experiments/go/move/movement_string.go
@@ -0,0 +1,27 @@
+// Code generated by "stringer -type=Movement"; DO NOT EDIT.
+
+package main
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[Unknown-0]
+	_ = x[Forward-1]
+	_ = x[Backward-2]
+	_ = x[Left-3]
+	_ = x[Right-4]
+}
+
+const _Movement_name = "UnknownForwardBackwardLeftRight"
+
+var _Movement_index = [...]uint8{0, 7, 14, 22, 26, 31}
+
+func (i Movement) String() string {
+	if i < 0 || i >= Movement(len(_Movement_index)-1) {
+		return "Movement(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _Movement_name[_Movement_index[i]:_Movement_index[i+1]]
+}