From 5dd85636fd4ce153d32c60ff9061fcd83b832236 Mon Sep 17 00:00:00 2001
From: Nuno Cruces <ncruces@users.noreply.github.com>
Date: Wed, 11 Dec 2019 10:29:31 +0000
Subject: [PATCH] File dialogs for macos.

---
 dialog/dialog_darwin.go | 138 ++++++++++++++++++++++++++++++++++++++++
 dialog/dialog_test.go   |  55 ++++++++++++++++
 go.mod                  |   3 +
 3 files changed, 196 insertions(+)
 create mode 100644 dialog/dialog_darwin.go
 create mode 100644 dialog/dialog_test.go
 create mode 100644 go.mod

diff --git a/dialog/dialog_darwin.go b/dialog/dialog_darwin.go
new file mode 100644
index 0000000..9a2780e
--- /dev/null
+++ b/dialog/dialog_darwin.go
@@ -0,0 +1,138 @@
+package dialog
+
+import (
+	"bytes"
+	"html/template"
+	"io"
+	"os/exec"
+	"strings"
+)
+
+func OpenFile(title, defaultPath string, filters []FileFilter) (string, error) {
+	cmd := exec.Command("osascript", "-l", "JavaScript")
+	cmd.Stdin = scriptExpand(scriptData{
+		Operation:   "chooseFile",
+		Title:       title,
+		DefaultPath: defaultPath,
+		Filter:      toFilter(filters),
+	})
+	out, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	if len(out) > 0 {
+		out = out[:len(out)-1]
+	}
+	return string(out), nil
+}
+
+func OpenFiles(title, defaultPath string, filters []FileFilter) ([]string, error) {
+	cmd := exec.Command("osascript", "-l", "JavaScript")
+	cmd.Stdin = scriptExpand(scriptData{
+		Operation:   "chooseFile",
+		Multiple:    true,
+		Title:       title,
+		DefaultPath: defaultPath,
+		Filter:      toFilter(filters),
+	})
+	out, err := cmd.Output()
+	if err != nil {
+		return nil, err
+	}
+	if len(out) > 0 {
+		out = out[:len(out)-1]
+	}
+	return strings.Split(string(out), "\x00"), nil
+}
+
+func SaveFile(title, defaultPath string, filters []FileFilter) (string, error) {
+	cmd := exec.Command("osascript", "-l", "JavaScript")
+	cmd.Stdin = scriptExpand(scriptData{
+		Operation:   "chooseFileName",
+		Title:       title,
+		DefaultPath: defaultPath,
+	})
+	out, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	if len(out) > 0 {
+		out = out[:len(out)-1]
+	}
+	return string(out), nil
+}
+
+func PickFolder(title, defaultPath string) (string, error) {
+	cmd := exec.Command("osascript", "-l", "JavaScript")
+	cmd.Stdin = scriptExpand(scriptData{
+		Operation:   "chooseFolder",
+		Title:       title,
+		DefaultPath: defaultPath,
+	})
+	out, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	if len(out) > 0 {
+		out = out[:len(out)-1]
+	}
+	return string(out), nil
+}
+
+type FileFilter struct {
+	Name string
+	Exts []string
+}
+
+func toFilter(filters []FileFilter) []string {
+	var filter []string
+	for _, f := range filters {
+		for _, e := range f.Exts {
+			filter = append(filter, strings.TrimPrefix(e, "."))
+		}
+	}
+	return filter
+}
+
+type scriptData struct {
+	Operation   string
+	Title       string
+	DefaultPath string
+	Filter      []string
+	Multiple    bool
+}
+
+func scriptExpand(data scriptData) io.Reader {
+	var buf bytes.Buffer
+
+	err := script.Execute(&buf, data)
+	if err != nil {
+		panic(err)
+	}
+
+	var slice = buf.Bytes()
+	return bytes.NewReader(slice[len("<script>") : len(slice)-len("</script>")])
+}
+
+var script = template.Must(template.New("").Parse(`<script>
+var app = Application.currentApplication();
+app.includeStandardAdditions = true;
+
+var opts = {};
+opts.withPrompt = {{.Title}};
+opts.multipleSelectionsAllowed = {{.Multiple}};
+
+{{if .DefaultPath}}
+  opts.defaultLocation = {{.DefaultPath}};
+{{end}}
+{{if .Filter}}
+  opts.ofType = {{.Filter}};
+{{end}}
+
+var ret = app[{{.Operation}}](opts);
+if (Array.isArray(ret)) {
+	ret.join('\0');
+} else {
+	ret.toString();
+}
+</script>`))
diff --git a/dialog/dialog_test.go b/dialog/dialog_test.go
new file mode 100644
index 0000000..211fdaa
--- /dev/null
+++ b/dialog/dialog_test.go
@@ -0,0 +1,55 @@
+package dialog
+
+import "testing"
+
+func TestOpenFile(t *testing.T) {
+	ret, err := OpenFile("", "", []FileFilter{
+		{"Go files", []string{".go"}},
+		{"Web files", []string{".html", ".js", ".css"}},
+		{"Image files", []string{".png", ".ico"}},
+	})
+
+	if err != nil {
+		t.Error(err)
+	} else {
+		t.Logf("%#v", ret)
+	}
+}
+
+func TestOpenFiles(t *testing.T) {
+	ret, err := OpenFiles("", "", []FileFilter{
+		{"Go files", []string{".go"}},
+		{"Web files", []string{".html", ".js", ".css"}},
+		{"Image files", []string{".png", ".ico"}},
+	})
+
+	if err != nil {
+		t.Error(err)
+	} else {
+		t.Logf("%#v", ret)
+	}
+}
+
+func TestSaveFile(t *testing.T) {
+	ret, err := SaveFile("", "", []FileFilter{
+		{"Go files", []string{".go"}},
+		{"Web files", []string{".html", ".js", ".css"}},
+		{"Image files", []string{".png", ".ico"}},
+	})
+
+	if err != nil {
+		t.Error(err)
+	} else {
+		t.Logf("%#v", ret)
+	}
+}
+
+func TestPickFolder(t *testing.T) {
+	ret, err := PickFolder("", "")
+
+	if err != nil {
+		t.Error(err)
+	} else {
+		t.Logf("%#v", ret)
+	}
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..ed74fb0
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module github.com/ncruces/go-ui
+
+go 1.13