tsk-9: Schedule queued message endpoint (#22)

Closes #9

Reviewed-on: phoenix/textsender-api#22
Co-authored-by: phoenix <kundeng00@pm.me>
Co-committed-by: phoenix <kundeng00@pm.me>

internal/store/scheduled_message_store.go

@@ -0,0 +1,36 @@
+package store
+
+import (
+	"context"
+	// "fmt"
+
+	// "github.com/google/uuid"
+	// "github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgxpool"
+
+	"git.kundeng.us/phoenix/textsender-models/pkg/message/scheduling"
+)
+
+type ScheduledMessageStore interface {
+	CreateScheduledMessage(ctx context.Context, schedMsg *scheduling.ScheduledMessage) error
+}
+
+type PGScheduledMessageStore struct {
+	db *pgxpool.Pool
+}
+
+func NewScheduledMessageStore(db *pgxpool.Pool) *PGScheduledMessageStore {
+	return &PGScheduledMessageStore{db: db}
+}
+
+func (s *PGScheduledMessageStore) CreateScheduledMessage(ctx context.Context, schedMsg *scheduling.ScheduledMessage) error {
+	query := `
+		INSERT INTO scheduled_messages (scheduled, status, user_id)
+		VALUES ($1, $2, $3)
+		RETURNING id, created
+	`
+
+	return s.db.QueryRow(ctx, query, schedMsg.Scheduled, schedMsg.Status, schedMsg.UserId).Scan(
+		&schedMsg.Id, &schedMsg.Created,
+	)
+}