From efffba1bb0373268385aafff02ea8e9c108e0abe Mon Sep 17 00:00:00 2001
From: Pedro Augusto Campos Dos Santos
 <38117637+ppcamp@users.noreply.github.com>
Date: Sat, 21 Sep 2024 15:47:56 -0300
Subject: [PATCH] feat: add early eval option support

---
 dialog/dynamic_options.go      | 32 ++++++++++++++++++++++++++++++++
 dialog/dynamic_options_test.go | 30 ++++++++++++++++++++++++++++++
 dialog/view.go                 | 21 ++++++++++++++++++++-
 3 files changed, 82 insertions(+), 1 deletion(-)
 create mode 100644 dialog/dynamic_options.go
 create mode 100644 dialog/dynamic_options_test.go

diff --git a/dialog/dynamic_options.go b/dialog/dynamic_options.go
new file mode 100644
index 0000000..4524257
--- /dev/null
+++ b/dialog/dynamic_options.go
@@ -0,0 +1,32 @@
+package dialog
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+	"os"
+	"strings"
+
+	runner "github.com/knqyf263/pet/cmd/runner"
+)
+
+// DynamicOptions run a command, split and returns an array of strings. It expect to
+// receive command substitions.
+//
+// Example:
+//
+//	DynamicOptions("$(fd -tf --hidden --no-ignore --max-depth=1 .)")
+func DynamicOptions(what string) ([]string, error) {
+	if what[:2] != "$(" || what[len(what)-1] != ')' {
+		return nil, fmt.Errorf("no evaluated command found: %v", what)
+	}
+
+	var w bytes.Buffer
+	err := runner.Run(what[2:len(what)-1], os.Stdin, &w)
+	if err != nil {
+		log.Fatal(what)
+		return nil, err
+	}
+
+	return strings.Split(strings.TrimSpace(w.String()), "\n"), nil
+}
diff --git a/dialog/dynamic_options_test.go b/dialog/dynamic_options_test.go
new file mode 100644
index 0000000..4465b5b
--- /dev/null
+++ b/dialog/dynamic_options_test.go
@@ -0,0 +1,30 @@
+package dialog_test
+
+import (
+	"slices"
+	"testing"
+
+	"github.com/knqyf263/pet/dialog"
+)
+
+const nameOfThisFile = "eval_test.go"
+
+func TestEvaluator(t *testing.T) {
+	param := "$(ls)"
+
+	e, err := dialog.DynamicOptions(param)
+	if err != nil {
+		t.Log(err)
+		t.FailNow()
+	}
+
+	if len(e) == 0 {
+		t.Log("Expected at least one result, but got none.")
+		t.FailNow()
+	}
+
+	if !slices.Contains(e, nameOfThisFile) {
+		t.Log("it should have the current file in this path")
+		t.FailNow()
+	}
+}
diff --git a/dialog/view.go b/dialog/view.go
index 25c44a4..5434cb2 100644
--- a/dialog/view.go
+++ b/dialog/view.go
@@ -134,7 +134,26 @@ func GenerateParamsLayout(params [][2]string, command string) {
 		r := regexp.MustCompile(parameterMultipleValueRegex)
 		matches := r.FindAllStringSubmatch(parameterValue, -1)
 
-		if len(matches) > 0 {
+		if len(matches) == 1 {
+			// Extract the default values and generate multiple params view
+			// using early evaluation context
+			matchedGroup := matches[0][1]
+			parameter := matchedGroup[2 : len(matchedGroup)-2]
+
+			options, err := DynamicOptions(parameter)
+			if err != nil {
+				// fallback to default evaluation (raw)
+				options = []string{parameter}
+			}
+
+			generateMultipleParameterView(
+				g, parameterKey, options, []int{
+					leftX,
+					(maxY / 4) + (idx+1)*layoutStep,
+					rightX,
+					(maxY / 4) + 2 + (idx+1)*layoutStep},
+				true)
+		} else if len(matches) > 0 {
 			// Extract the default values and generate multiple params view
 			parameters := []string{}
 			for _, p := range matches {