Fully implement api free()

src/main/api.zig

@@ -9,15 +9,23 @@ pub const Uuid = util.Uuid;
 
 // Frees an api struct and its fields allocated from alloc
 pub fn free(alloc: std.mem.Allocator, val: anytype) void {
-    inline for (std.meta.fields(@TypeOf(val))) |f| {
-        // TODO
-        if (f.field_type == []u8 or f.field_type == []const u8) {
-            alloc.free(@field(val, f.name));
-        } else if (f.field_type == Uuid or f.field_type == DateTime) {
-            // nothing
-        } else {
-            @compileError("unsupported field type " ++ @typeName(f.field_type));
-        }
+    switch (@typeInfo(@TypeOf(val))) {
+        .Pointer => |ptr_info| switch (ptr_info.size) {
+            .One => {
+                free(alloc, val.*);
+                alloc.destroy(val);
+            },
+            .Slice => {
+                for (val) |elem| free(alloc, elem);
+                alloc.free(val);
+            },
+            else => unreachable,
+        },
+        .Struct => inline for (std.meta.fields(@TypeOf(val))) |f| free(alloc, @field(val, f.name)),
+        .Array => for (val) |elem| free(alloc, elem),
+        .Optional => if (val) |opt| free(alloc, opt),
+        .Bool, .Int, .Float, .Enum => {},
+        else => unreachable,
     }
 }