package repository

import (
	"errors"
	"fmt"
	"time"

	"gorm.io/gorm"
	"wails-app/internal/dao"
	"wails-app/internal/global"
)

// Repository 封装设备接入记录读写，避免 API 层直接拼接 GORM 条件。
type Repository struct{}

func New() *Repository { return &Repository{} }

func (r *Repository) db() *gorm.DB { return global.GVA_DB }

func (r *Repository) CreateDiscovery(record *dao.DeviceDiscovery) error {
	if r.db() == nil {
		return errors.New("数据库未初始化")
	}
	return r.db().Create(record).Error
}

func (r *Repository) LatestDiscovery(deviceID string) (*dao.DeviceDiscovery, error) {
	return r.latestDiscovery(deviceID, "")
}

func (r *Repository) LatestDiscoveryByMethod(deviceID, method string) (*dao.DeviceDiscovery, error) {
	return r.latestDiscovery(deviceID, method)
}

func (r *Repository) latestDiscovery(deviceID, method string) (*dao.DeviceDiscovery, error) {
	if r.db() == nil {
		return nil, errors.New("数据库未初始化")
	}
	var record dao.DeviceDiscovery
	query := r.db().Where("device_id = ?", deviceID)
	if method != "" {
		query = query.Where("provision_method = ?", method)
	}
	result := query.Order("created_at DESC").First(&record)
	if errors.Is(result.Error, gorm.ErrRecordNotFound) {
		return nil, fmt.Errorf("设备身份不存在或已过期")
	}
	if result.Error != nil {
		return nil, result.Error
	}
	if time.Now().After(record.ExpiredAt) {
		return nil, fmt.Errorf("设备身份记录已过期，请重新读取")
	}
	return &record, nil
}

func (r *Repository) SaveDiscovery(record *dao.DeviceDiscovery) error {
	if r.db() == nil {
		return errors.New("数据库未初始化")
	}
	return r.db().Save(record).Error
}

func (r *Repository) ActiveDiscoveries() ([]dao.DeviceDiscovery, error) {
	if r.db() == nil {
		return nil, errors.New("数据库未初始化")
	}
	var records []dao.DeviceDiscovery
	result := r.db().Where("expired_at > ? AND provision_method = ?", time.Now(), "auto_udp").Order("created_at DESC").Find(&records)
	return records, result.Error
}

func (r *Repository) ReaderByDeviceID(deviceID string) (*dao.UHFReader, error) {
	if r.db() == nil {
		return nil, errors.New("数据库未初始化")
	}
	var reader dao.UHFReader
	result := r.db().Where("device_id = ?", deviceID).First(&reader)
	if errors.Is(result.Error, gorm.ErrRecordNotFound) {
		return nil, nil
	}
	return &reader, result.Error
}