package usecase

import (
	"encoding/json"
	"users_management/m/model/entity"
	"users_management/m/repository"

	"github.com/google/uuid"
)

type ActivityLogUseCase interface {
    LogActivity(userID uuid.UUID, action, resource string, resourceID *string, oldData, newData interface{}, ipAddress, userAgent, details string) error
    GetUserLogs(userID uuid.UUID, page, limit int) ([]entity.ActivityLog, int64, error)
    GetAllLogs(page, limit int) ([]entity.ActivityLog, int64, error)
    GetTeknisinLogs(page, limit int) ([]entity.ActivityLog, int64, error)
}

type activityLogUseCase struct {
    activityLogRepo repository.ActivityLogRepo
}

func NewActivityLogUseCase(activityLogRepo repository.ActivityLogRepo) ActivityLogUseCase {
    return &activityLogUseCase{
        activityLogRepo: activityLogRepo,
    }
}

func (uc *activityLogUseCase) LogActivity(userID uuid.UUID, action, resource string, resourceID *string, oldData, newData interface{}, ipAddress, userAgent, details string) error {
    var oldDataJSON, newDataJSON *string
    
    if oldData != nil {
        oldBytes, err := json.Marshal(oldData)
        if err == nil {
            oldStr := string(oldBytes)
            oldDataJSON = &oldStr
        }
    }
    
    if newData != nil {
        newBytes, err := json.Marshal(newData)
        if err == nil {
            newStr := string(newBytes)
            newDataJSON = &newStr
        }
    }
    
    var detailsPtr *string
    if details != "" {
        detailsPtr = &details
    }
    
    log := entity.ActivityLog{
        ID:         uuid.New(),
        UserID:     userID,
        Action:     action,
        Resource:   resource,
        ResourceID: resourceID,
        OldData:    oldDataJSON,
        NewData:    newDataJSON,
        IPAddress:  ipAddress,
        UserAgent:  userAgent,
        Details:    detailsPtr,
    }
    
    return uc.activityLogRepo.Create(log)
}

func (uc *activityLogUseCase) GetUserLogs(userID uuid.UUID, page, limit int) ([]entity.ActivityLog, int64, error) {
    offset := (page - 1) * limit
    logs, err := uc.activityLogRepo.GetByUserID(userID, limit, offset)
    if err != nil {
        return nil, 0, err
    }
    
    total, err := uc.activityLogRepo.CountByUserID(userID)
    return logs, total, err
}

func (uc *activityLogUseCase) GetAllLogs(page, limit int) ([]entity.ActivityLog, int64, error) {
    offset := (page - 1) * limit
    logs, err := uc.activityLogRepo.GetAllForAdmins(limit, offset)
    if err != nil {
        return nil, 0, err
    }
    
    total, err := uc.activityLogRepo.CountAll()
    return logs, total, err
}

func (uc *activityLogUseCase) GetTeknisinLogs(page, limit int) ([]entity.ActivityLog, int64, error) {
    offset := (page - 1) * limit
    logs, err := uc.activityLogRepo.GetByUserRole("Teknisi", limit, offset)
    if err != nil {
        return nil, 0, err
    }
    
    total, err := uc.activityLogRepo.CountByUserRole("Teknisi")
    return logs, total, err
}