refactor

internal/domain/entities/counter.go

@@ -0,0 +1,60 @@
+package entities
+
+import "time"
+
+// Counter represents a counter entity
+type Counter struct {
+	ID          int       `json:"id" db:"id"`
+	UserID      int       `json:"user_id" db:"user_id"`
+	Name        string    `json:"name" db:"name"`
+	Description string    `json:"description" db:"description"`
+	CreatedAt   time.Time `json:"created_at" db:"created_at"`
+	UpdatedAt   time.Time `json:"updated_at" db:"updated_at"`
+}
+
+// CounterEntry represents a single increment/decrement entry
+type CounterEntry struct {
+	ID        int       `json:"id" db:"id"`
+	CounterID int       `json:"counter_id" db:"counter_id"`
+	Value     int       `json:"value" db:"value"` // +1 for increment, -1 for decrement
+	Date      time.Time `json:"date" db:"date"`
+	CreatedAt time.Time `json:"created_at" db:"created_at"`
+}
+
+// CounterWithStats represents a counter with aggregated statistics
+type CounterWithStats struct {
+	Counter
+	TotalValue int `json:"total_value"`
+	TodayValue int `json:"today_value"`
+	WeekValue  int `json:"week_value"`
+	MonthValue int `json:"month_value"`
+	EntryCount int `json:"entry_count"`
+}
+
+// DailyStat represents daily statistics for a counter
+type DailyStat struct {
+	Date  time.Time `json:"date"`
+	Total int       `json:"total"`
+}
+
+// Validate validates counter data
+func (c *Counter) Validate() error {
+	if c.Name == "" {
+		return ErrInvalidCounterName
+	}
+	if c.UserID <= 0 {
+		return ErrInvalidUserID
+	}
+	return nil
+}
+
+// Validate validates counter entry data
+func (ce *CounterEntry) Validate() error {
+	if ce.CounterID <= 0 {
+		return ErrInvalidCounterID
+	}
+	if ce.Value == 0 {
+		return ErrInvalidEntryValue
+	}
+	return nil
+}

internal/domain/entities/errors.go

@@ -0,0 +1,19 @@
+package entities
+
+import "errors"
+
+// Domain errors
+var (
+	ErrInvalidUsername      = errors.New("username is required")
+	ErrInvalidEmail         = errors.New("email is required")
+	ErrInvalidPassword      = errors.New("password is required")
+	ErrInvalidCounterName   = errors.New("counter name is required")
+	ErrInvalidUserID        = errors.New("invalid user ID")
+	ErrInvalidCounterID     = errors.New("invalid counter ID")
+	ErrInvalidEntryValue    = errors.New("entry value cannot be zero")
+	ErrUserNotFound         = errors.New("user not found")
+	ErrCounterNotFound      = errors.New("counter not found")
+	ErrCounterEntryNotFound = errors.New("counter entry not found")
+	ErrUserAlreadyExists    = errors.New("user already exists")
+	ErrInvalidCredentials   = errors.New("invalid credentials")
+)

internal/domain/entities/user.go

@@ -0,0 +1,32 @@
+package entities
+
+import "time"
+
+// User represents a registered user
+type User struct {
+	ID        int       `json:"id" db:"id"`
+	Username  string    `json:"username" db:"username"`
+	Email     string    `json:"email" db:"email"`
+	Password  string    `json:"-" db:"password"` // Hidden from JSON
+	CreatedAt time.Time `json:"created_at" db:"created_at"`
+	UpdatedAt time.Time `json:"updated_at" db:"updated_at"`
+}
+
+// Validate validates user data
+func (u *User) Validate() error {
+	if u.Username == "" {
+		return ErrInvalidUsername
+	}
+	if u.Email == "" {
+		return ErrInvalidEmail
+	}
+	if u.Password == "" {
+		return ErrInvalidPassword
+	}
+	return nil
+}
+
+// ClearPassword removes password from user for safe serialization
+func (u *User) ClearPassword() {
+	u.Password = ""
+}