package entities

import (
	"time"

	"github.com/google/uuid"
	"github.com/shopspring/decimal"
	"gorm.io/gorm"

	"tyapi-server/internal/domains/finance/value_objects"
)

// ApplicationStatus 申请状态枚举
type ApplicationStatus string

const (
	ApplicationStatusPending   ApplicationStatus = "pending"   // 待处理
	ApplicationStatusCompleted ApplicationStatus = "completed" // 已完成（已上传发票）
	ApplicationStatusRejected  ApplicationStatus = "rejected"  // 已拒绝
)

// InvoiceApplication 发票申请聚合根
type InvoiceApplication struct {
	// 基础标识
	ID          string `gorm:"primaryKey;type:varchar(36)" json:"id" comment:"申请唯一标识"`
	UserID      string `gorm:"type:varchar(36);not null;index" json:"user_id" comment:"申请用户ID"`

	// 申请信息
	InvoiceType value_objects.InvoiceType `gorm:"type:varchar(20);not null" json:"invoice_type" comment:"发票类型"`
	Amount      decimal.Decimal           `gorm:"type:decimal(20,8);not null" json:"amount" comment:"申请金额"`
	Status      ApplicationStatus         `gorm:"type:varchar(20);not null;default:'pending';index" json:"status" comment:"申请状态"`

	// 开票信息快照（申请时的信息，用于历史记录追踪）
	CompanyName    string `gorm:"type:varchar(200);not null" json:"company_name" comment:"公司名称"`
	TaxpayerID     string `gorm:"type:varchar(50);not null" json:"taxpayer_id" comment:"纳税人识别号"`
	BankName       string `gorm:"type:varchar(100)" json:"bank_name" comment:"开户银行"`
	BankAccount    string `gorm:"type:varchar(50)" json:"bank_account" comment:"银行账号"`
	CompanyAddress string `gorm:"type:varchar(500)" json:"company_address" comment:"企业地址"`
	CompanyPhone   string `gorm:"type:varchar(20)" json:"company_phone" comment:"企业电话"`
	ReceivingEmail string `gorm:"type:varchar(100);not null" json:"receiving_email" comment:"发票接收邮箱"`
	
	// 开票信息引用（关联到用户开票信息表，用于模板功能）
	UserInvoiceInfoID string `gorm:"type:varchar(36);not null" json:"user_invoice_info_id" comment:"用户开票信息ID"`

	// 文件信息（申请通过后才有）
	FileID       *string    `gorm:"type:varchar(200)" json:"file_id,omitempty" comment:"文件ID"`
	FileName     *string    `gorm:"type:varchar(200)" json:"file_name,omitempty" comment:"文件名"`
	FileSize     *int64     `json:"file_size,omitempty" comment:"文件大小"`
	FileURL      *string    `gorm:"type:varchar(500)" json:"file_url,omitempty" comment:"文件URL"`
	
	// 处理信息
	ProcessedBy   *string    `gorm:"type:varchar(36)" json:"processed_by,omitempty" comment:"处理人ID"`
	ProcessedAt   *time.Time `json:"processed_at,omitempty" comment:"处理时间"`
	RejectReason  *string    `gorm:"type:varchar(500)" json:"reject_reason,omitempty" comment:"拒绝原因"`
	AdminNotes    *string    `gorm:"type:varchar(500)" json:"admin_notes,omitempty" comment:"管理员备注"`

	// 时间戳字段
	CreatedAt time.Time      `gorm:"autoCreateTime" json:"created_at" comment:"创建时间"`
	UpdatedAt time.Time      `gorm:"autoUpdateTime" json:"updated_at" comment:"更新时间"`
	DeletedAt gorm.DeletedAt `gorm:"index" json:"-" comment:"软删除时间"`
}

// TableName 指定数据库表名
func (InvoiceApplication) TableName() string {
	return "invoice_applications"
}

// BeforeCreate GORM钩子：创建前自动生成UUID
func (ia *InvoiceApplication) BeforeCreate(tx *gorm.DB) error {
	if ia.ID == "" {
		ia.ID = uuid.New().String()
	}
	return nil
}

// IsPending 检查是否为待处理状态
func (ia *InvoiceApplication) IsPending() bool {
	return ia.Status == ApplicationStatusPending
}



// IsCompleted 检查是否为已完成状态
func (ia *InvoiceApplication) IsCompleted() bool {
	return ia.Status == ApplicationStatusCompleted
}

// IsRejected 检查是否为已拒绝状态
func (ia *InvoiceApplication) IsRejected() bool {
	return ia.Status == ApplicationStatusRejected
}

// CanProcess 检查是否可以处理
func (ia *InvoiceApplication) CanProcess() bool {
	return ia.IsPending()
}

// CanReject 检查是否可以拒绝
func (ia *InvoiceApplication) CanReject() bool {
	return ia.IsPending()
}



// MarkCompleted 标记为已完成
func (ia *InvoiceApplication) MarkCompleted(processedBy string) {
	ia.Status = ApplicationStatusCompleted
	ia.ProcessedBy = &processedBy
	now := time.Now()
	ia.ProcessedAt = &now
}

// MarkRejected 标记为已拒绝
func (ia *InvoiceApplication) MarkRejected(reason string, processedBy string) {
	ia.Status = ApplicationStatusRejected
	ia.RejectReason = &reason
	ia.ProcessedBy = &processedBy
	now := time.Now()
	ia.ProcessedAt = &now
}

// SetFileInfo 设置文件信息
func (ia *InvoiceApplication) SetFileInfo(fileID, fileName, fileURL string, fileSize int64) {
	ia.FileID = &fileID
	ia.FileName = &fileName
	ia.FileURL = &fileURL
	ia.FileSize = &fileSize
}

// NewInvoiceApplication 工厂方法
func NewInvoiceApplication(userID string, invoiceType value_objects.InvoiceType, amount decimal.Decimal, userInvoiceInfoID string) *InvoiceApplication {
	return &InvoiceApplication{
		UserID:             userID,
		InvoiceType:        invoiceType,
		Amount:             amount,
		Status:             ApplicationStatusPending,
		UserInvoiceInfoID:  userInvoiceInfoID,
	}
}

// SetInvoiceInfoSnapshot 设置开票信息快照
func (ia *InvoiceApplication) SetInvoiceInfoSnapshot(info *value_objects.InvoiceInfo) {
	ia.CompanyName = info.CompanyName
	ia.TaxpayerID = info.TaxpayerID
	ia.BankName = info.BankName
	ia.BankAccount = info.BankAccount
	ia.CompanyAddress = info.CompanyAddress
	ia.CompanyPhone = info.CompanyPhone
	ia.ReceivingEmail = info.ReceivingEmail
}

// GetInvoiceInfoSnapshot 获取开票信息快照
func (ia *InvoiceApplication) GetInvoiceInfoSnapshot() *value_objects.InvoiceInfo {
	return value_objects.NewInvoiceInfo(
		ia.CompanyName,
		ia.TaxpayerID,
		ia.BankName,
		ia.BankAccount,
		ia.CompanyAddress,
		ia.CompanyPhone,
		ia.ReceivingEmail,
	)
}