add dev resources; plumb GUI_ENV_FILE/API_ENV_FILE/API_DESI_DATA into run targets

gui/lib/local/dotenv/src/dotenv.odin

@@ -80,13 +80,26 @@ destroy :: proc(env: map[string]string) {
 	delete(env)
 }
 
+// env_key returns the env key that should bind to a struct field. It prefers
+// an explicit `env:"NAME"` tag; when the tag is absent or empty it falls
+// back to the field's name. Matching against the parsed map is
+// case-insensitive, so API_URL maps onto api_url (or an `env:"API_URL"` tag).
+@(private)
+env_key_for_field :: proc(field: reflect.Struct_Field) -> string {
+	if tag_key, ok := reflect.struct_tag_lookup(field.tag, "env");
+	   ok && tag_key != "" {
+		return tag_key
+	}
+	return field.name
+}
+
 // decode populates dest's fields from env, matching each field by name
-// (case-insensitively, so API_URL maps onto api_url). Values are converted
-// to the field's type: string is cloned as-is into allocator, integers are
-// parsed with strconv.parse_int (decimal/hex/negative), booleans with
-// strconv.parse_bool, and floats with strconv.parse_f64. Keys missing from
-// env leave the field at its zero value. It returns false if a present value
-// cannot be converted to the field's type.
+// (or by an `env:"NAME"` struct tag). Values are converted to the field's
+// type: string is cloned as-is into allocator, integers are parsed with
+// strconv.parse_int (decimal/hex/negative), booleans with strconv.parse_bool,
+// and floats with strconv.parse_f64. Keys missing from env leave the field
+// at its zero value. It returns false if a present value cannot be converted
+// to the field's type.
 decode :: proc(
 	env: map[string]string,
 	dest: ^$T,
@@ -98,11 +111,12 @@ decode :: proc(
 		return false
 	}
 
-	name: string
 	value: string
 	field_ptr := rawptr(dest)
+	st: reflect.Struct_Field
 	for _, i in fields.names[:fields.field_count] {
-		name = fields.names[i]
+		st = reflect.struct_field_at(T, i)
+		name := env_key_for_field(st)
 		value = ""
 		found := false
 		for key, v in env {
@@ -157,7 +171,7 @@ decode :: proc(
 				return false
 			}
 		case:
-			// unsupported field type (slices, pointers, ...) is left untouched
+		// unsupported field type (slices, pointers, ...) is left untouched
 		}
 	}
 

gui/lib/local/dotenv/test/dotenv_test.odin

@@ -12,6 +12,16 @@ Test_Config :: struct {
 	ratio:   f64,
 }
 
+Tagged_Config :: struct {
+	api_url: string `env:"API_URL"`,
+	port:    int `env:"PORT"`,
+	debug:   bool `env:"DEBUG"`,
+}
+
+Tagged_Empty :: struct {
+	api_url: string `env:""`,
+}
+
 // load_env writes src to a unique temp file and parses it via parse_file.
 // The returned map owns its strings; callers must destroy it.
 load_env :: proc(t: ^testing.T, src: string) -> map[string]string {
@@ -199,3 +209,37 @@ test_decode_hex_and_negative_ints :: proc(t: ^testing.T) {
 	testing.expect(t, dotenv.decode(env, &cfg))
 	testing.expect(t, cfg.port == 31, "hex int should decode")
 }
+
+@(test)
+test_decode_honors_env_tags :: proc(t: ^testing.T) {
+	env := load_env(t, "API_URL=http://127.0.0.1:8080\nPORT=9090\nDEBUG=true\n")
+	defer dotenv.destroy(env)
+
+	cfg := Tagged_Config{}
+	testing.expect(t, dotenv.decode(env, &cfg))
+	defer delete(cfg.api_url)
+
+	testing.expect(
+		t,
+		cfg.api_url == "http://127.0.0.1:8080",
+		"env tag should bind API_URL",
+	)
+	testing.expect(t, cfg.port == 9090, "env tag should bind PORT")
+	testing.expect(t, cfg.debug == true, "env tag should bind DEBUG")
+}
+
+@(test)
+test_decode_empty_env_tag_falls_back_to_field_name :: proc(t: ^testing.T) {
+	env := load_env(t, "api_url=http://fallback\n")
+	defer dotenv.destroy(env)
+
+	cfg := Tagged_Empty{}
+	testing.expect(t, dotenv.decode(env, &cfg))
+	defer delete(cfg.api_url)
+
+	testing.expect(
+		t,
+		cfg.api_url == "http://fallback",
+		"empty env tag should use field name",
+	)
+}

gui/src/config.odin

@@ -4,11 +4,21 @@ import "core:os"
 import dotenv "lib:dotenv/src"
 
 Config :: struct {
-	api_url: string,
+	api_url: string `env:"API_URL"`,
 }
 
 get_config :: proc(env_file: ^string = nil) -> (^Config, ^Error) {
-	env, _ := dotenv.parse_file(".env", context.temp_allocator)
+	path := ".env"
+	if env_file != nil && env_file^ != "" {
+		path = env_file^
+	} else if from_env, ok := os.lookup_env(
+		"GUI_ENV_FILE",
+		context.temp_allocator,
+	); ok {
+		path = from_env
+	}
+
+	env, _ := dotenv.parse_file(path, context.temp_allocator)
 	defer dotenv.destroy(env)
 
 	c := new(Config)