feat: index reader

cache/index.go

@@ -0,0 +1,41 @@
+package cache
+
+import (
+	"os"
+
+	"github.com/Yakiyo/tilde/utils"
+	"github.com/Yakiyo/tilde/where"
+	json "github.com/json-iterator/go"
+)
+
+// using string instead of `error` cz stupid ide screams when i use
+// capitalized error strings. REEEEEEEEEEEEEEEEEEEEEE!
+
+// read index.json from cache dir
+func ReadIndex() (Index, string) {
+	indexPath := where.Index()
+	index := Index{}
+	if !utils.FsExists(indexPath) {
+		return index, "Cannot find index file in cache directory. Use the `--update/-u` flag to update cache"
+	}
+	f, err := os.ReadFile(indexPath)
+	if err != nil {
+		return index, err.Error()
+	}
+	err = json.Unmarshal(f, &index)
+	return index, err.Error()
+}
+
+type Index struct {
+	Commands []Command `json:"commands"`
+}
+
+type Command struct {
+	Name    string   `json:"name"`
+	Targets []Target `json:"targets"`
+}
+
+type Target struct {
+	Os       string `json:"os"`
+	Language string `json:"language"`
+}