Merge pull request 'read the best solution for each task in contest' (#8) from get-contest-extension into develop

Reviewed-on: #8
Reviewed-by: Vyacheslav Birin <vyacheslav1557@noreply.localhost>

internal/tester/delivery/rest/handlers.go

@@ -99,6 +99,15 @@ func (h *TesterHandlers) GetContest(c *fiber.Ctx, id int32) error {
 		return c.SendStatus(pkg.ToREST(err))
 	}
 
+	var participantId int32 = 2
+
+	solutions, err := h.contestsUC.ReadBestSolutions(c.Context(), id, participantId)
+
+	m := make(map[int32]*models.Solution)
+
+	for i := 0; i < len(solutions); i++ {
+		m[solutions[i].TaskPosition] = solutions[i]
+	}
 	resp := testerv1.GetContestResponse{
 		Contest: C2C(*contest),
 		Tasks: make([]struct {
@@ -108,11 +117,15 @@ func (h *TesterHandlers) GetContest(c *fiber.Ctx, id int32) error {
 	}
 
 	for i, task := range tasks {
+		solution := testerv1.Solution{}
+		if sol, ok := m[task.Position]; ok {
+			solution = S2S(*sol)
+		}
 		resp.Tasks[i] = struct {
 			Solution testerv1.Solution      `json:"solution"`
 			Task     testerv1.TasksListItem `json:"task"`
 		}{
-			Solution: testerv1.Solution{},
+			Solution: solution,
 			Task:     TLI2TLI(*task),
 		}
 	}

internal/tester/pg_repository.go

@@ -49,4 +49,5 @@ type ContestRepository interface {
 	ListSolutions(ctx context.Context, filter models.SolutionsFilter) (*models.SolutionsList, error)
 	ReadTask(ctx context.Context, id int32) (*models.Task, error)
 	ReadMonitor(ctx context.Context, id int32) (*models.Monitor, error)
+	ReadBestSolutions(ctx context.Context, contestId int32, participantId int32) ([]*models.Solution, error)
 }

internal/tester/repository/pg_contests_repository.go

@@ -626,3 +626,65 @@ func (r *ContestRepository) ReadMonitor(ctx context.Context, contestId int32) (*
 
 	return &monitor, nil
 }
+
+const (
+	// state=5 - AC
+	readBestSolutions = `
+		WITH contest_tasks AS (
+    SELECT t.id AS task_id,
+           t.position AS task_position,
+           t.contest_id,
+           t.problem_id,
+           t.created_at,
+           t.updated_at,
+           p.title AS task_title,
+           c.title AS contest_title
+    FROM tasks t
+             LEFT JOIN problems p ON p.id = t.problem_id
+             LEFT JOIN  contests c ON c.id = t.contest_id
+    WHERE t.contest_id = ?
+),
+     best_solutions AS (
+         SELECT DISTINCT ON (s.task_id)
+             *
+         FROM solutions s
+         WHERE s.participant_id = ?
+         ORDER BY s.task_id, s.score DESC, s.created_at DESC
+     )
+SELECT
+    s.id,
+    s.participant_id,
+    p.name AS participant_name,
+    s.solution,
+    s.state,
+    s.score,
+    s.penalty,
+    s.time_stat,
+    s.memory_stat,
+    s.language,
+    ct.task_id,
+    ct.task_position,
+    ct.task_title,
+    ct.contest_id,
+    ct.contest_title,
+    s.updated_at,
+    s.created_at
+FROM contest_tasks ct
+         LEFT JOIN best_solutions s ON s.task_id = ct.task_id
+         LEFT JOIN participants p ON p.id = s.participant_id WHERE s.id IS NOT NULL
+ORDER BY ct.task_position
+`
+)
+
+func (r *ContestRepository) ReadBestSolutions(ctx context.Context, contestId int32, participantId int32) ([]*models.Solution, error) {
+	const op = "ContestRepository.ReadBestSolutions"
+	var solutions []*models.Solution
+	query := r.db.Rebind(readBestSolutions)
+	err := r.db.SelectContext(ctx, &solutions, query, contestId, participantId)
+
+	if err != nil {
+		return nil, handlePgErr(err, op)
+	}
+
+	return solutions, nil
+}

internal/tester/usecase.go

@@ -31,4 +31,5 @@ type ContestUseCase interface {
 	ListSolutions(ctx context.Context, filter models.SolutionsFilter) (*models.SolutionsList, error)
 	ReadTask(ctx context.Context, id int32) (*models.Task, error)
 	ReadMonitor(ctx context.Context, id int32) (*models.Monitor, error)
+	ReadBestSolutions(ctx context.Context, contestId int32, participantId int32) ([]*models.Solution, error)
 }

internal/tester/usecase/contests_usecase.go

@@ -85,3 +85,7 @@ func (uc *ContestUseCase) ReadTask(ctx context.Context, id int32) (*models.Task,
 func (uc *ContestUseCase) ReadMonitor(ctx context.Context, contestId int32) (*models.Monitor, error) {
 	return uc.contestRepo.ReadMonitor(ctx, contestId)
 }
+
+func (uc *ContestUseCase) ReadBestSolutions(ctx context.Context, contestId int32, participantId int32) ([]*models.Solution, error) {
+	return uc.contestRepo.ReadBestSolutions(ctx, contestId, participantId)
+}