package models

import (
	"time"

	"github.com/google/uuid"
	"gorm.io/gorm"
)

// BaseEntity enthält gemeinsame Felder für alle Entitäten
type BaseEntity struct {
	ID        uuid.UUID      `gorm:"type:uuid;primary_key"`
	CreatedAt time.Time      `gorm:"autoCreateTime"`
	UpdatedAt time.Time      `gorm:"autoUpdateTime"`
	DeletedAt gorm.DeletedAt `gorm:"index"`
}

// BeforeCreate setzt eine neue UUID vor dem Erstellen
func (base *BaseEntity) BeforeCreate(tx *gorm.DB) error {
	if base.ID == uuid.Nil {
		base.ID = uuid.New()
	}
	return nil
}

// TenantEntity erweitert BaseEntity um Company-ID für Multi-Tenancy
type TenantEntity struct {
	BaseEntity
	CompanyID uuid.UUID `gorm:"type:uuid;index:idx_tenant"`
}

// Role repräsentiert eine Benutzerrolle
type Role struct {
	BaseEntity
	Name        string `gorm:"unique;not null"`
	Description string
	Permissions []Permission `gorm:"many2many:role_permissions;"`
}

// Permission repräsentiert eine einzelne Berechtigung
type Permission struct {
	BaseEntity
	Resource string `gorm:"not null"`
	Action   string `gorm:"not null"`
	UniqueID string `gorm:"uniqueIndex"`
}

// User repräsentiert einen Benutzer im System
type User struct {
	TenantEntity
	Email        string `gorm:"uniqueIndex;not null"`
	FirstName    string
	LastName     string
	PasswordHash string    `gorm:"not null"`
	RoleID       uuid.UUID `gorm:"type:uuid"`
	Role         Role      `gorm:"foreignKey:RoleID"`
	HourlyRate   float64
	IsActive     bool `gorm:"default:true"`
}

// FullName gibt den vollständigen Namen des Benutzers zurück
func (u User) FullName() string {
	return u.FirstName + " " + u.LastName
}

// TimeEntry repräsentiert eine Zeitbuchung
type TimeEntry struct {
	TenantEntity
	UserID             uuid.UUID  `gorm:"type:uuid;index:idx_user"`
	User               User       `gorm:"foreignKey:UserID"`
	ProjectID          uuid.UUID  `gorm:"type:uuid;index:idx_project"`
	Project            Project    `gorm:"foreignKey:ProjectID"`
	ActivityID         uuid.UUID  `gorm:"type:uuid"`
	Activity           Activity   `gorm:"foreignKey:ActivityID"`
	TaskID             *uuid.UUID `gorm:"type:uuid;null"`
	Task               *Task      `gorm:"foreignKey:TaskID"`
	StartTime          time.Time  `gorm:"not null;index:idx_time_range"`
	EndTime            time.Time  `gorm:"not null;index:idx_time_range"`
	DurationMinutes    int        `gorm:"not null"`
	Description        string
	BillablePercentage int `gorm:"default:100"`
	BillingRate        float64
}

type Project struct {
	TenantEntity
	Name string
}

type Activity struct {
	TenantEntity
	Name string
}

type Task struct {
	TenantEntity
	Name string
}

// CalculateBillableAmount berechnet den abrechenbaren Betrag
func (t TimeEntry) CalculateBillableAmount() float64 {
	hours := float64(t.DurationMinutes) / 60.0
	return hours * t.BillingRate * (float64(t.BillablePercentage) / 100.0)
}