Add Support for Advance Labels ( LabelV2)

Add Support for Custom Migration to keep supporting two database( sqlite and postgres)
Migration from Label to LabelV2

migrations/base.go

@@ -0,0 +1,100 @@
+package migrations
+
+import (
+	"context"
+	"time"
+
+	"donetick.com/core/logging"
+	"gorm.io/gorm"
+)
+
+type Migration struct {
+	// DB Representation for migration table, mainly used for tracking the migration status.
+	ID          string    `json:"id" gorm:"primary_key"`
+	Description string    `json:"description" gorm:"column:description"`
+	AppliedAt   time.Time `json:"appliedAt" gorm:"column:applied_at"`
+}
+
+type MigrationScript interface {
+	// Actual migration script interface which needs to be implemented by each migration script.
+	Description() string
+	ID() string
+	Up(ctx context.Context, db *gorm.DB) error
+	Down(ctx context.Context, db *gorm.DB) error
+}
+
+var registry []MigrationScript
+
+// Register a migration
+func Register(migration MigrationScript) {
+	registry = append(registry, migration)
+}
+
+// Sort the migrations by ID
+func sortMigrations(migrations []MigrationScript) []MigrationScript {
+	for i := 0; i < len(migrations); i++ {
+		for j := i + 1; j < len(migrations); j++ {
+			if migrations[i].ID() > migrations[j].ID() {
+				migrations[i], migrations[j] = migrations[j], migrations[i]
+			}
+		}
+	}
+	return migrations
+}
+
+// Run pending migrations
+func Run(ctx context.Context, db *gorm.DB) error {
+	log := logging.FromContext(ctx)
+	// Confirm the migrations table exists :)
+	if err := db.AutoMigrate(&Migration{}); err != nil {
+		return err
+	}
+
+	// Sort the registry by ID
+	registry = sortMigrations(registry)
+	var successfulCount int
+	var skippedCount int
+	for _, migration := range registry {
+		// Check if migration is already applied
+		var count int64
+		db.Model(&Migration{}).Where("id = ?", migration.ID()).Count(&count)
+		if count > 0 {
+			skippedCount++
+			log.Debug("Skipping migration %s as it is already applied", migration.ID())
+			continue
+		}
+
+		// Run the migration
+		log.Infof("Applying migration: %s", migration.ID())
+		if err := migration.Up(ctx, db); err != nil {
+
+			log.Errorf("Failed to apply migration %s: %s", migration.ID(), err)
+			if err := migration.Down(ctx, db); err != nil {
+				log.Errorf("Failed to rollback migration %s: %s\n", migration.ID(), err)
+			}
+			return err
+		}
+
+		// Record the migration
+		record := Migration{
+			ID:          migration.ID(),
+			Description: migration.Description(),
+			AppliedAt:   time.Now().UTC(),
+		}
+
+		if err := db.Create(&record).Error; err != nil {
+			log.Errorf("Failed to record migration %s: %s\n", migration.ID(), err)
+			return err
+		}
+
+		successfulCount++
+	}
+
+	if len(registry) == 0 {
+		log.Info("Migratons: No pending migrations")
+	} else {
+		var failedCount = len(registry) - successfulCount - skippedCount
+		log.Infof("Migrations: %d successful, %d failed, %d skipped, %d total in registry", successfulCount, failedCount, skippedCount, len(registry))
+	}
+	return nil
+}