package repository

import (
	"errors"
	"time"

	"git.huangwc.com/pig/pig-farm-controller/internal/infra/models"
	"gorm.io/gorm"
)

// PigSickLogListOptions 定义了查询病猪日志时的可选参数
type PigSickLogListOptions struct {
	PigBatchID        *uint
	PenID             *uint
	Reason            *models.PigBatchSickPigReasonType
	TreatmentLocation *models.PigBatchSickPigTreatmentLocation
	OperatorID        *uint
	StartTime         *time.Time // 基于 happened_at 字段
	EndTime           *time.Time // 基于 happened_at 字段
	OrderBy           string     // 例如 "happened_at desc"
}

// PigSickLogRepository 定义了与病猪日志模型相关的数据库操作接口。
type PigSickLogRepository interface {
	// CreatePigSickLog 创建一条新的病猪日志记录
	CreatePigSickLog(log *models.PigSickLog) error
	CreatePigSickLogTx(tx *gorm.DB, log *models.PigSickLog) error

	// GetLastLogByBatchTx 在事务中获取指定批次和猪栏的最新一条 PigSickLog 记录
	GetLastLogByBatchTx(tx *gorm.DB, batchID uint) (*models.PigSickLog, error)

	// ListPigSickLogs 支持分页和过滤的病猪日志列表查询
	ListPigSickLogs(opts PigSickLogListOptions, page, pageSize int) ([]models.PigSickLog, int64, error)
}

// gormPigSickLogRepository 是 PigSickLogRepository 接口的 GORM 实现。
type gormPigSickLogRepository struct {
	db *gorm.DB
}

// NewGormPigSickLogRepository 创建一个新的 PigSickLogRepository GORM 实现实例。
func NewGormPigSickLogRepository(db *gorm.DB) PigSickLogRepository {
	return &gormPigSickLogRepository{db: db}
}

// CreatePigSickLog 创建一条新的病猪日志记录
func (r *gormPigSickLogRepository) CreatePigSickLog(log *models.PigSickLog) error {
	return r.CreatePigSickLogTx(r.db, log)
}
func (r *gormPigSickLogRepository) CreatePigSickLogTx(tx *gorm.DB, log *models.PigSickLog) error {
	return tx.Create(log).Error
}

// GetLastLogByBatchTx 在事务中获取指定批次和猪栏的最新一条 PigSickLog 记录
func (r *gormPigSickLogRepository) GetLastLogByBatchTx(tx *gorm.DB, batchID uint) (*models.PigSickLog, error) {
	var lastLog models.PigSickLog
	err := tx.
		Where("pig_batch_id = ?", batchID).
		Order("happened_at DESC"). // 按时间降序排列
		First(&lastLog).Error      // 获取第一条记录 (即最新一条)

	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, gorm.ErrRecordNotFound // 明确返回记录未找到错误
		}
		return nil, err
	}
	return &lastLog, nil
}

// ListPigSickLogs 实现了分页和过滤查询病猪日志的功能
func (r *gormPigSickLogRepository) ListPigSickLogs(opts PigSickLogListOptions, page, pageSize int) ([]models.PigSickLog, int64, error) {
	if page <= 0 || pageSize <= 0 {
		return nil, 0, ErrInvalidPagination
	}

	var results []models.PigSickLog
	var total int64

	query := r.db.Model(&models.PigSickLog{})

	if opts.PigBatchID != nil {
		query = query.Where("pig_batch_id = ?", *opts.PigBatchID)
	}
	if opts.PenID != nil {
		query = query.Where("pen_id = ?", *opts.PenID)
	}
	if opts.Reason != nil {
		query = query.Where("reason = ?", *opts.Reason)
	}
	if opts.TreatmentLocation != nil {
		query = query.Where("treatment_location = ?", *opts.TreatmentLocation)
	}
	if opts.OperatorID != nil {
		query = query.Where("operator_id = ?", *opts.OperatorID)
	}
	if opts.StartTime != nil {
		query = query.Where("happened_at >= ?", *opts.StartTime)
	}
	if opts.EndTime != nil {
		query = query.Where("happened_at <= ?", *opts.EndTime)
	}

	if err := query.Count(&total).Error; err != nil {
		return nil, 0, err
	}

	orderBy := "happened_at DESC"
	if opts.OrderBy != "" {
		orderBy = opts.OrderBy
	}
	query = query.Order(orderBy)

	offset := (page - 1) * pageSize
	err := query.Limit(pageSize).Offset(offset).Find(&results).Error

	return results, total, err
}