package service

import (
	"errors"
	"fmt"
	"strings"

	commonRepo "gitlab.com/mbugroup/lti-api.git/internal/common/repository"
	commonSvc "gitlab.com/mbugroup/lti-api.git/internal/common/service"
	entity "gitlab.com/mbugroup/lti-api.git/internal/entities"
	rProductWarehouse "gitlab.com/mbugroup/lti-api.git/internal/modules/inventory/product-warehouses/repositories"
	KandangRepo "gitlab.com/mbugroup/lti-api.git/internal/modules/master/kandangs/repositories"
	rWarehouse "gitlab.com/mbugroup/lti-api.git/internal/modules/master/warehouses/repositories"
	repository "gitlab.com/mbugroup/lti-api.git/internal/modules/production/chickins/repositories"
	validation "gitlab.com/mbugroup/lti-api.git/internal/modules/production/chickins/validations"
	rProjectFlock "gitlab.com/mbugroup/lti-api.git/internal/modules/production/project_flocks/repositories"
	"gitlab.com/mbugroup/lti-api.git/internal/utils"

	"github.com/go-playground/validator/v10"
	"github.com/gofiber/fiber/v2"
	"github.com/sirupsen/logrus"
	"gorm.io/gorm"
)

type ChickinService interface {
	GetAll(ctx *fiber.Ctx, params *validation.Query) ([]entity.ProjectChickin, int64, error)
	GetOne(ctx *fiber.Ctx, id uint) (*entity.ProjectChickin, error)
	CreateOne(ctx *fiber.Ctx, req *validation.Create) (*entity.ProjectChickin, error)
	UpdateOne(ctx *fiber.Ctx, req *validation.Update, id uint) (*entity.ProjectChickin, error)
	DeleteOne(ctx *fiber.Ctx, id uint) error
	Approval(ctx *fiber.Ctx, req *validation.Approve) ([]entity.ProjectChickin, error)
}

type chickinService struct {
	Log                        *logrus.Logger
	Validate                   *validator.Validate
	Repository                 repository.ProjectChickinRepository
	KandangRepo                KandangRepo.KandangRepository
	WarehouseRepo              rWarehouse.WarehouseRepository
	ProductWarehouseRepo       rProductWarehouse.ProductWarehouseRepository
	ProjectFlockRepo           rProjectFlock.ProjectflockRepository
	ProjectflockKandangRepo    rProjectFlock.ProjectFlockKandangRepository
	ProjectflockPopulationRepo rProjectFlock.ProjectFlockPopulationRepository
	ProjectChickinDetailRepo   repository.ProjectChickinDetailRepository
}

func NewChickinService(repo repository.ProjectChickinRepository, kandangRepo KandangRepo.KandangRepository, warehouseRepo rWarehouse.WarehouseRepository, productWarehouseRepo rProductWarehouse.ProductWarehouseRepository, projectFlockRepo rProjectFlock.ProjectflockRepository, projectflockkandangRepo rProjectFlock.ProjectFlockKandangRepository, projectflockpopulationRepo rProjectFlock.ProjectFlockPopulationRepository, projectChickinDetailRepo repository.ProjectChickinDetailRepository, validate *validator.Validate) ChickinService {
	return &chickinService{
		Log:                        utils.Log,
		Validate:                   validate,
		Repository:                 repo,
		KandangRepo:                kandangRepo,
		WarehouseRepo:              warehouseRepo,
		ProductWarehouseRepo:       productWarehouseRepo,
		ProjectFlockRepo:           projectFlockRepo,
		ProjectflockKandangRepo:    projectflockkandangRepo,
		ProjectflockPopulationRepo: projectflockpopulationRepo,
		ProjectChickinDetailRepo:   projectChickinDetailRepo,
	}
}

func (s chickinService) withRelations(db *gorm.DB) *gorm.DB {
	return db.
		Preload("CreatedUser").
		Preload("ProjectFlockKandang.Kandang").
		Preload("ProjectFlockKandang.Kandang.Location").
		Preload("ProjectFlockKandang.Kandang.Location.Area").
		Preload("ProjectFlockKandang.Kandang.Pic").
		Preload("ProjectFlockKandang.ProjectFlock").
		Preload("ProjectFlockKandang.ProjectFlock.Flock").
		Preload("ProjectFlockKandang.ProjectFlock.Area").
		Preload("ProjectFlockKandang.ProjectFlock.Fcr").
		Preload("ProjectFlockKandang.ProjectFlock.Location").
		Preload("ProjectFlockKandang.ProjectFlock.Location.Area")

}

func (s chickinService) GetAll(c *fiber.Ctx, params *validation.Query) ([]entity.ProjectChickin, int64, error) {
	if err := s.Validate.Struct(params); err != nil {
		return nil, 0, err
	}

	offset := (params.Page - 1) * params.Limit

	chickins, total, err := s.Repository.GetAll(c.Context(), offset, params.Limit, func(db *gorm.DB) *gorm.DB {
		db = s.withRelations(db)
		if params.ProjectFlockKandangId != 0 {
			return db.Where("project_flock_kandang_id = ?", params.ProjectFlockKandangId)
		}
		return db.Order("created_at DESC").Order("updated_at DESC")
	})
	if err != nil {
		s.Log.Errorf("Failed to get chickins: %+v", err)
		return nil, 0, err
	}
	return chickins, total, nil
}

func (s chickinService) GetOne(c *fiber.Ctx, id uint) (*entity.ProjectChickin, error) {

	chickin, err := s.Repository.GetByID(c.Context(), id, s.withRelations)
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return nil, fiber.NewError(fiber.StatusNotFound, "Chickin not found")
	}
	if err != nil {
		s.Log.Errorf("Failed get chickin by id: %+v", err)
		return nil, err
	}
	return chickin, nil
}

func (s *chickinService) CreateOne(c *fiber.Ctx, req *validation.Create) (*entity.ProjectChickin, error) {
	if err := s.Validate.Struct(req); err != nil {
		return nil, err
	}

	projectFlockKandang, err := s.ProjectflockKandangRepo.GetByID(c.Context(), req.ProjectFlockKandangId)
	if err != nil {
		return nil, fiber.NewError(fiber.StatusNotFound, "Project Flock Kandang not found")
	}

	warehouse, err := s.WarehouseRepo.GetByKandangID(c.Context(), projectFlockKandang.KandangId)
	if err != nil {
		return nil, fiber.NewError(fiber.StatusNotFound, "Warehouse for Kandang not found")
	}

	var productWarehouses []entity.ProductWarehouse

	if strings.ToUpper(strings.TrimSpace(projectFlockKandang.ProjectFlock.Category)) == string(utils.ProjectFlockCategoryGrowing) {

		productWarehouses, err = s.ProductWarehouseRepo.GetByCategoryCodeAndWarehouseID(c.Context(), "DOC", warehouse.Id)
		if err != nil || len(productWarehouses) == 0 {
			return nil, fiber.NewError(fiber.StatusNotFound, "Product for growing category in the Kandang's warehouse not found")
		}
	}

	chickinDate, err := utils.ParseDateString(req.ChickInDate)
	if err != nil {
		return nil, fiber.NewError(fiber.StatusBadRequest, "Invalid ChickInDate format")
	}

	actorID := uint(1) // todo nanti ambil dari auth context
	newChikins := make([]*entity.ProjectChickin, 0)
	for _, productWarehouse := range productWarehouses {

		if productWarehouse.Quantity > 0 {
			newChickin := &entity.ProjectChickin{
				ProjectFlockKandangId: req.ProjectFlockKandangId,
				ChickInDate:           chickinDate,
				UsageQty:              0,
				PendingUsageQty:       productWarehouse.Quantity,
				ProductWarehouseId:    productWarehouse.Id,
				Notes:                 req.Note,
				CreatedBy:             actorID,
			}

			newChikins = append(newChikins, newChickin)
		}
	}

	if len(newChikins) == 0 {
		return nil, fiber.NewError(fiber.StatusBadRequest, "No chickins to create")
	}

	err = s.Repository.DB().WithContext(c.Context()).Transaction(func(dbTransaction *gorm.DB) error {

		approvalSvcTx := commonSvc.NewApprovalService(commonRepo.NewApprovalRepository(dbTransaction))
		productWarehouseTx := s.ProductWarehouseRepo.WithTx(dbTransaction)

		if err := s.Repository.WithTx(dbTransaction).CreateMany(c.Context(), newChikins, nil); err != nil {
			return err
		}

		latest, err := approvalSvcTx.LatestByTarget(c.Context(), utils.ApprovalWorkflowProjectFlockKandang, projectFlockKandang.Id, nil)
		if err != nil {
			return err
		}

		for _, chickin := range newChikins {

			updates := map[string]any{"quantity": 0}

			if err := productWarehouseTx.PatchOne(c.Context(), chickin.ProductWarehouseId, updates, nil); err != nil {
				if errors.Is(err, gorm.ErrRecordNotFound) {
					return fmt.Errorf("failed to update product warehouse quantity for id %d", chickin.ProductWarehouseId)
				}
				return err
			}
		}

		if latest == nil {

			action := entity.ApprovalActionCreated
			if _, err := approvalSvcTx.CreateApproval(c.Context(), utils.ApprovalWorkflowProjectFlockKandang, projectFlockKandang.Id, utils.ProjectFlockKandangStepPengajuan, &action, actorID, nil); err != nil {
				lower := strings.ToLower(err.Error())
				if !(strings.Contains(lower, "duplicate") || strings.Contains(lower, "unique constraint") || strings.Contains(lower, "23505")) {
					return err
				}
			}
		}

		return nil
	})
	if err != nil {
		return nil, fiber.NewError(fiber.StatusBadRequest, err.Error())
	}

	return newChikins[0], nil
}

func (s chickinService) UpdateOne(c *fiber.Ctx, req *validation.Update, id uint) (*entity.ProjectChickin, error) {
	if err := s.Validate.Struct(req); err != nil {
		return nil, err
	}

	updateBody := make(map[string]any)

	if req.ChickInDate != "" {
		updateBody["chick_in_date"] = req.ChickInDate
	}
	if req.Note != "" {
		// entity uses `Notes` => column `notes`
		updateBody["notes"] = req.Note
	}
	if len(updateBody) == 0 {
		return s.GetOne(c, id)
	}

	if err := s.Repository.PatchOne(c.Context(), id, updateBody, nil); err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, fiber.NewError(fiber.StatusNotFound, "Chickin not found")
		}
		s.Log.Errorf("Failed to update chickin: %+v", err)
		return nil, err
	}

	return s.GetOne(c, id)
}

func (s chickinService) DeleteOne(c *fiber.Ctx, id uint) error {

	// Simplified delete: directly call repository delete. Complex restore logic removed for now.
	if err := s.Repository.DeleteOne(c.Context(), id); err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return fiber.NewError(fiber.StatusNotFound, "Chickin not found")
		}
		return err
	}

	return nil
}

func (s chickinService) Approval(c *fiber.Ctx, req *validation.Approve) ([]entity.ProjectChickin, error) {
	if err := s.Validate.Struct(req); err != nil {
		return nil, err
	}

	actorID := uint(1) // todo nanti ambil dari auth context

	var action entity.ApprovalAction
	switch strings.ToUpper(strings.TrimSpace(req.Action)) {
	case string(entity.ApprovalActionRejected):
		action = entity.ApprovalActionRejected
	case string(entity.ApprovalActionApproved):
		action = entity.ApprovalActionApproved
	default:
		return nil, fiber.NewError(fiber.StatusBadRequest, "action must be APPROVED or REJECTED")
	}

	approvableIDs := uniqueUintSlice(req.ApprovableIds)
	if len(approvableIDs) == 0 {
		return nil, fiber.NewError(fiber.StatusBadRequest, "approvable_ids must contain at least one id")
	}

	step := utils.ProjectFlockKandangStepPengajuan
	if action == entity.ApprovalActionApproved {
		step = utils.ProjectFlockKandangStepDisetujui
	}

	err := s.Repository.DB().WithContext(c.Context()).Transaction(func(dbTransaction *gorm.DB) error {
		approvalSvc := commonSvc.NewApprovalService(commonRepo.NewApprovalRepository(dbTransaction))
		ProjectFlockPopulationRepotx := s.ProjectflockPopulationRepo.WithTx(dbTransaction)
		chickinRepoTx := s.Repository.WithTx(dbTransaction)

		for _, approvableID := range approvableIDs {

			exists, err := s.ProjectflockKandangRepo.WithTx(dbTransaction).IdExists(c.Context(), approvableID)
			if err != nil {
				return err
			}
			if !exists {
				return fiber.NewError(fiber.StatusNotFound, fmt.Sprintf("ProjectFlockKandang %d not found", approvableID))
			}

			if _, err := approvalSvc.CreateApproval(
				c.Context(),
				utils.ApprovalWorkflowProjectFlockKandang,
				approvableID,
				step,
				&action,
				actorID,
				req.Notes,
			); err != nil {

				lower := strings.ToLower(err.Error())
				if !(strings.Contains(lower, "duplicate") || strings.Contains(lower, "unique constraint") || strings.Contains(lower, "23505")) {
					return err
				}
				s.Log.Infof("ignored duplicate approval for kandang %d: %v", approvableID, err)
			}

			if action == entity.ApprovalActionApproved {

				var chickins []entity.ProjectChickin
				if err := chickinRepoTx.DB().WithContext(c.Context()).Where("project_flock_kandang_id = ?", approvableID).Find(&chickins).Error; err != nil {
					return err
				}

				for _, chickin := range chickins {
					population := &entity.ProjectFlockPopulation{
						ProjectChickinId:   chickin.Id,
						ProductWarehouseId: chickin.ProductWarehouseId,
						TotalQty:           chickin.PendingUsageQty,
						TotalUsedQty:       0,
						Notes:              chickin.Notes,
						CreatedBy:          actorID,
					}
					if err := ProjectFlockPopulationRepotx.CreateOne(c.Context(), population, nil); err != nil {
						lower := strings.ToLower(err.Error())
						if !(strings.Contains(lower, "duplicate") || strings.Contains(lower, "unique constraint") || strings.Contains(lower, "23505")) {
							return err
						}
						s.Log.Infof("ignored duplicate population for chickin %d: %v", chickin.Id, err)
					}
				}

			}

		}

		return nil
	})

	if err != nil {
		if fiberErr, ok := err.(*fiber.Error); ok {
			return nil, fiberErr
		}
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, fiber.NewError(fiber.StatusNotFound, "Chickin not found")
		}
		s.Log.Errorf("Failed to record approval for chickins %+v: %+v", approvableIDs, err)
		return nil, fiber.NewError(fiber.StatusInternalServerError, "Failed to record approval")
	}

	updated := make([]entity.ProjectChickin, 0)
	for _, kandangID := range approvableIDs {
		var chickins []entity.ProjectChickin
		if err := s.Repository.DB().WithContext(c.Context()).Where("project_flock_kandang_id = ?", kandangID).Find(&chickins).Error; err != nil {
			return nil, err
		}
		updated = append(updated, chickins...)
	}

	return updated, nil
}

func uniqueUintSlice(values []uint) []uint {
	seen := make(map[uint]struct{}, len(values))
	result := make([]uint, 0, len(values))
	for _, v := range values {
		if _, ok := seen[v]; ok {
			continue
		}
		seen[v] = struct{}{}
		result = append(result, v)
	}
	return result
}