package repositories

import (
	"agent-desk/internal/models"
	"agent-desk/internal/pkg/enums"
	"errors"
	"github.com/mlogclub/simple/sqls"
	"gorm.io/gorm"
	"gorm.io/gorm/clause"
	"time"
)

var SupportAvailabilityRepository = &supportAvailabilityRepository{}

type supportAvailabilityRepository struct{}

func (r *supportAvailabilityRepository) Calendar(db *gorm.DB, teamID int64) (*models.SupportCalendar, error) {
	var item models.SupportCalendar
	err := db.Where("team_id = ?", teamID).Take(&item).Error
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return nil, nil
	}
	return &item, err
}
func (r *supportAvailabilityRepository) SaveCalendar(db *gorm.DB, item *models.SupportCalendar) error {
	return db.Clauses(clause.OnConflict{Columns: []clause.Column{{Name: "team_id"}}, DoUpdates: clause.AssignmentColumns([]string{"mode", "timezone", "weekly_json", "exceptions_json", "updated_at"})}).Create(item).Error
}
func (r *supportAvailabilityRepository) RenewPresence(db *gorm.DB, item *models.AgentPresenceLease) error {
	return db.Clauses(clause.OnConflict{Columns: []clause.Column{{Name: "id"}}, DoUpdates: clause.AssignmentColumns([]string{"expires_at"})}).Create(item).Error
}
func (r *supportAvailabilityRepository) EndPresence(db *gorm.DB, id string, at time.Time) error {
	return db.Model(&models.AgentPresenceLease{}).Where("id = ? AND expires_at > ?", id, at).Update("expires_at", at).Error
}
func (r *supportAvailabilityRepository) PrunePresence(db *gorm.DB, now time.Time) error {
	return db.Where("expires_at <= ?", now).Delete(&models.AgentPresenceLease{}).Error
}
func (r *supportAvailabilityRepository) OnlineUsers(db *gorm.DB, userIDs []int64, now time.Time) (map[int64]bool, error) {
	result := map[int64]bool{}
	if len(userIDs) == 0 {
		return result, nil
	}
	var leases []models.AgentPresenceLease
	if err := db.Where("user_id IN ? AND expires_at > ?", userIDs, now).Find(&leases).Error; err != nil {
		return nil, err
	}
	sessionIDs := make([]int64, 0, len(leases))
	for _, lease := range leases {
		sessionIDs = append(sessionIDs, lease.LoginSessionID)
	}
	if len(sessionIDs) == 0 {
		return result, nil
	}
	var sessions []models.LoginSession
	if err := db.Select("id", "user_id", "expired_at", "revoked_at").Where("id IN ? AND expired_at > ? AND revoked_at IS NULL", sessionIDs, now).Find(&sessions).Error; err != nil {
		return nil, err
	}
	valid := map[int64]int64{}
	for _, session := range sessions {
		valid[session.ID] = session.UserID
	}
	for _, lease := range leases {
		if valid[lease.LoginSessionID] == lease.UserID {
			result[lease.UserID] = true
		}
	}
	return result, nil
}

// A portable write acquires the profile row's write lock on MySQL and the
// transaction write lock on SQLite. All assignment paths take this before count.
func (r *supportAvailabilityRepository) LockProfile(db *gorm.DB, userID int64) (*models.AgentProfile, error) {
	result := db.Model(&models.AgentProfile{}).Where("user_id = ?", userID).UpdateColumn("assignment_version", gorm.Expr("assignment_version + 1"))
	if result.Error != nil {
		return nil, result.Error
	}
	if result.RowsAffected == 0 {
		return nil, gorm.ErrRecordNotFound
	}
	var item models.AgentProfile
	err := db.Where("user_id = ?", userID).Take(&item).Error
	return &item, err
}
func (r *supportAvailabilityRepository) ActiveCount(db *gorm.DB, userID, excludeConversationID int64) (int, error) {
	var count int64
	q := db.Model(&models.Conversation{}).Where("current_assignee_id = ? AND status = ?", userID, enums.IMConversationStatusActive)
	if excludeConversationID > 0 {
		q = q.Where("id <> ?", excludeConversationID)
	}
	err := q.Count(&count).Error
	return int(count), err
}
func (r *supportAvailabilityRepository) LegacySchedules(db *gorm.DB, teamID int64, now time.Time) ([]models.AgentTeamSchedule, error) {
	var items []models.AgentTeamSchedule
	err := db.Where("team_id = ? AND status = ? AND end_at > ?", teamID, enums.StatusOk, now).Order("start_at ASC").Find(&items).Error
	return items, err
}
func (r *supportAvailabilityRepository) Profiles(db *gorm.DB, teamIDs []int64) ([]models.AgentProfile, error) {
	var items []models.AgentProfile
	q := db.Where("status <> ?", enums.StatusDeleted)
	if teamIDs != nil {
		if len(teamIDs) == 0 {
			return []models.AgentProfile{}, nil
		}
		q = q.Where("team_id IN ?", teamIDs)
	}
	err := q.Order("id ASC").Find(&items).Error
	return items, err
}
func (r *supportAvailabilityRepository) User(db *gorm.DB, id int64) (*models.User, error) {
	var item models.User
	err := db.First(&item, id).Error
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return nil, nil
	}
	return &item, err
}
func (r *supportAvailabilityRepository) Team(db *gorm.DB, id int64) (*models.AgentTeam, error) {
	var item models.AgentTeam
	err := db.First(&item, id).Error
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return nil, nil
	}
	return &item, err
}

func (r *supportAvailabilityRepository) AssignConversation(db *gorm.DB, previous *models.Conversation, values map[string]any) error {
	result := db.Model(&models.Conversation{}).Where("id = ? AND status = ? AND current_assignee_id = ?", previous.ID, previous.Status, previous.CurrentAssigneeID).Updates(values)
	if result.Error != nil {
		return result.Error
	}
	if result.RowsAffected != 1 {
		return gorm.ErrInvalidTransaction
	}
	return nil
}

func (r *supportAvailabilityRepository) ProfileByUser(db *gorm.DB, userID int64) (*models.AgentProfile, error) {
	var item models.AgentProfile
	err := db.Where("user_id = ?", userID).Take(&item).Error
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return nil, nil
	}
	return &item, err
}

// EffectiveStatusCondition mirrors the vacation-boundary policy for paginated
// list filters. Filtering the stored Vacation value would contradict the badge.
func (r *supportAvailabilityRepository) EffectiveStatusCondition(cnd *sqls.Cnd, status enums.ServiceStatus, now time.Time) {
	cnd.Where(`(CASE WHEN service_status <> ? THEN service_status
 WHEN absence_start_at IS NOT NULL AND absence_end_at IS NOT NULL AND absence_start_at <= ? AND absence_end_at > ? THEN ?
 WHEN availability_return_status >= ? AND availability_return_status <= ? THEN availability_return_status
 ELSE ? END) = ?`, enums.ServiceStatusVacation, now, now, enums.ServiceStatusVacation, enums.ServiceStatusIdle, enums.ServiceStatusUnavailable, enums.ServiceStatusUnavailable, status)
}