user.go

package deploykit

import (
	"context"
	"time"
)

// Role represents a user's authorization level.
type Role string

const (
	RoleAdmin  Role = "admin"
	RoleMember Role = "member"
)

// ValidRole reports whether r is a known role.
func ValidRole(r Role) bool {
	return r == RoleAdmin || r == RoleMember
}

// User represents a registered user account.
type User struct {
	ID           string    `json:"id"`
	Email        string    `json:"email"`
	Name         string    `json:"name"`
	Role         Role      `json:"role"`
	PasswordHash string    `json:"-"`
	CreatedAt    time.Time `json:"created_at"`
	UpdatedAt    time.Time `json:"updated_at"`
}

// UserService manages users.
type UserService interface {
	// CreateUser creates a new user. The password is hashed by the
	// implementation. The ID and timestamps are set automatically.
	// Returns ECONFLICT if the email is already taken.
	CreateUser(ctx context.Context, create UserCreate) (*User, error)

	// GetUser returns a user by ID.
	// Returns ENOTFOUND if the user does not exist.
	GetUser(ctx context.Context, id string) (*User, error)

	// ListUsers returns a filtered, paginated list of users
	// and the total matching count.
	ListUsers(ctx context.Context, filter UserFilter) ([]*User, int, error)

	// UpdateUser applies a partial update to a user by ID.
	// Returns the updated user. Returns ENOTFOUND if not found.
	// Returns ECONFLICT if the new email is already taken.
	UpdateUser(ctx context.Context, id string, update UserUpdate) (*User, error)

	// DeleteUser permanently removes a user by ID.
	// Returns ENOTFOUND if not found.
	DeleteUser(ctx context.Context, id string) error
}

// UserCreate holds fields required to create a user.
type UserCreate struct {
	Email    string `json:"email"`
	Name     string `json:"name"`
	Password string `json:"password"`
	Role     Role   `json:"role"`
}

// Validate checks that all required fields are present.
func (c *UserCreate) Validate() error {
	ve := NewValidationErrors()
	if c.Email == "" {
		ve.Add("email", "Email is required.")
	}
	if c.Name == "" {
		ve.Add("name", "Name is required.")
	}
	if c.Password == "" {
		ve.Add("password", "Password is required.")
	} else if len(c.Password) < 8 {
		ve.Add("password", "Password must be at least 8 characters.")
	}
	return ve.Err()
}

// UserUpdate holds fields that can be updated on a user.
// Nil pointer fields are left unchanged.
type UserUpdate struct {
	Email    *string `json:"email"`
	Name     *string `json:"name"`
	Password *string `json:"password"`
	Role     *Role   `json:"role"`
}

// Validate checks update fields.
func (u *UserUpdate) Validate() error {
	ve := NewValidationErrors()
	if u.Email != nil && *u.Email == "" {
		ve.Add("email", "Email cannot be empty.")
	}
	if u.Name != nil && *u.Name == "" {
		ve.Add("name", "Name cannot be empty.")
	}
	if u.Password != nil && *u.Password == "" {
		ve.Add("password", "Password cannot be empty.")
	} else if u.Password != nil && len(*u.Password) < 8 {
		ve.Add("password", "Password must be at least 8 characters.")
	}
	if u.Role != nil && !ValidRole(*u.Role) {
		ve.Add("role", "Role must be 'admin' or 'member'.")
	}
	return ve.Err()
}

// ProfileUpdate holds fields a user can update on their own profile.
// CurrentPassword is required only when changing the password.
// Role is intentionally excluded — users cannot change their own role.
type ProfileUpdate struct {
	Email           *string `json:"email"`
	Name            *string `json:"name"`
	NewPassword     *string `json:"new_password"`
	CurrentPassword string  `json:"current_password"`
}

// Validate checks profile update fields.
func (u *ProfileUpdate) Validate() error {
	ve := NewValidationErrors()
	if u.Email != nil && *u.Email == "" {
		ve.Add("email", "Email cannot be empty.")
	}
	if u.Name != nil && *u.Name == "" {
		ve.Add("name", "Name cannot be empty.")
	}
	if u.NewPassword != nil {
		if *u.NewPassword == "" {
			ve.Add("new_password", "New password cannot be empty.")
		} else if len(*u.NewPassword) < 8 {
			ve.Add("new_password", "New password must be at least 8 characters.")
		}
		if u.CurrentPassword == "" {
			ve.Add("current_password", "Current password is required to change your password.")
		}
	}
	return ve.Err()
}

// UserFilter controls filtering and pagination for listing users.
type UserFilter struct {
	Email  *string
	Role   *Role
	Offset int
	Limit  int
}