feat: add solutions service

internal/models/solution.go

@@ -7,7 +7,6 @@ type Solution struct {
 	ParticipantId *int32     `db:"participant_id"`
 	ProblemId     *int32     `db:"problem_id"`
 	LanguageId    *int32     `db:"language_id"`
-	ContestId     *int32     `db:"contest_id"`
 	SolutionHash  *string    `db:"solution_hash"`
 	Result        *int32     `db:"result"`
 	CreatedAt     *time.Time `db:"created_at"`

internal/models/testgroup.go

@@ -0,0 +1,24 @@
+package models
+
+import "time"
+
+type TestingStrategy int32
+
+const (
+    EachTestTS      TestingStrategy = 1;
+    CompleteGroupTS TestingStrategy = 2;
+)
+
+type Testgroup struct {
+	Id               *int32     `db:"id"`
+	ProblemId        *int32     `db:"problem_id"`
+    TestingStrategy  *int32     `db:"testing_strategy"`
+}
+
+func (TestingStrategy ts) Valid() error {
+	switch ts {
+	case EachTestTS, CompleteGroupTS:
+		return nil
+	}
+	return lib.ErrBadTestingStrategy
+}