added support for dotenv files and config

gui/src/config.odin

@@ -0,0 +1,29 @@
+package main
+
+import "lib:dotenv"
+
+Config :: struct {
+	api_url: string,
+}
+
+get_config :: proc() -> (^Config, ^Error) {
+	env, _ := dotenv.parse_file(".env", context.temp_allocator)
+	defer dotenv.destroy(env)
+
+	c := new(Config)
+
+	c.api_url = dotenv.get_string(env, "API_URL")
+
+	if err := validate_config(c); err != nil {
+		return nil, err
+	}
+
+	return c, nil
+}
+
+validate_config :: proc(c: ^Config) -> ^Error {
+	err := new(Error)
+	if c.api_url == "" do err.type = .Config; err.message = "'API_URL' is required"
+
+	return err
+}

gui/src/error.odin

@@ -0,0 +1,20 @@
+package main
+
+import "core:fmt"
+import "core:strings"
+ErrorType :: enum {
+	Config,
+	API,
+}
+
+Error :: struct {
+	type:    ErrorType,
+	message: string,
+}
+
+format_error :: proc(err: ^Error) -> string {
+	sb := strings.builder_make(context.temp_allocator)
+
+	return fmt.sbprintf(&sb, "[%s] => %s", err.type, err.message)
+}
+

gui/src/main.odin

@@ -24,6 +24,13 @@ universe: [dynamic]Galaxy
 rng: rand.Default_Random_State
 
 main :: proc() {
+
+	c: ^Config
+
+	if c, err := get_config(); err != nil {
+		panic(format_error(err))
+	}
+
 	rng = rand.create(0xDE51_0000)
 	context.random_generator = rand.default_random_generator(&rng)
 
@@ -103,11 +110,5 @@ draw :: proc() {
 	}
 
 	rl.DrawFPS(10, 10)
-	rl.DrawText(
-		"DESI Explorer — drag to rotate, scroll to zoom",
-		10,
-		34,
-		18,
-		rl.RAYWHITE,
-	)
+	rl.DrawText("DESI Explorer — drag to rotate, scroll to zoom", 10, 34, 18, rl.RAYWHITE)
 }