package service

import (
	"context"

	"apskel-pos-be/internal/appcontext"
	"apskel-pos-be/internal/constants"
	"apskel-pos-be/internal/contract"
	"apskel-pos-be/internal/processor"
	"apskel-pos-be/internal/transformer"

	"github.com/google/uuid"
)

type CashAdvanceService interface {
	CreateCashAdvance(ctx context.Context, apctx *appcontext.ContextInfo, req *contract.CreateCashAdvanceRequest) *contract.Response
	UpdateCashAdvance(ctx context.Context, apctx *appcontext.ContextInfo, id uuid.UUID, req *contract.UpdateCashAdvanceRequest) *contract.Response
	DeleteCashAdvance(ctx context.Context, apctx *appcontext.ContextInfo, id uuid.UUID) *contract.Response
	GetCashAdvanceByID(ctx context.Context, apctx *appcontext.ContextInfo, id uuid.UUID) *contract.Response
	ListCashAdvances(ctx context.Context, apctx *appcontext.ContextInfo, req *contract.ListCashAdvancesRequest) *contract.Response
	UpdateCashAdvanceStatus(ctx context.Context, apctx *appcontext.ContextInfo, id uuid.UUID, status string) *contract.Response
	ListCashAdvanceTeams(ctx context.Context, apctx *appcontext.ContextInfo) *contract.Response
}

type CashAdvanceServiceImpl struct {
	cashAdvanceProcessor processor.CashAdvanceProcessor
}

func NewCashAdvanceService(cashAdvanceProcessor processor.CashAdvanceProcessor) *CashAdvanceServiceImpl {
	return &CashAdvanceServiceImpl{cashAdvanceProcessor: cashAdvanceProcessor}
}

func (s *CashAdvanceServiceImpl) CreateCashAdvance(ctx context.Context, apctx *appcontext.ContextInfo, req *contract.CreateCashAdvanceRequest) *contract.Response {
	modelReq, err := transformer.CreateCashAdvanceRequestToModel(req)
	if err != nil {
		errorResp := contract.NewResponseError(constants.MalformedFieldErrorCode, constants.CashAdvanceServiceEntity, "Invalid date format. Use YYYY-MM-DD format")
		return contract.BuildErrorResponse([]*contract.ResponseError{errorResp})
	}

	cashAdvance, err := s.cashAdvanceProcessor.CreateCashAdvance(ctx, apctx.OrganizationID, outletFromContext(apctx), modelReq)
	if err != nil {
		errorResp := contract.NewResponseError(constants.InternalServerErrorCode, constants.CashAdvanceServiceEntity, err.Error())
		return contract.BuildErrorResponse([]*contract.ResponseError{errorResp})
	}

	return contract.BuildSuccessResponse(transformer.CashAdvanceModelResponseToResponse(cashAdvance))
}

func (s *CashAdvanceServiceImpl) UpdateCashAdvance(ctx context.Context, apctx *appcontext.ContextInfo, id uuid.UUID, req *contract.UpdateCashAdvanceRequest) *contract.Response {
	modelReq, err := transformer.UpdateCashAdvanceRequestToModel(req)
	if err != nil {
		errorResp := contract.NewResponseError(constants.MalformedFieldErrorCode, constants.CashAdvanceServiceEntity, "Invalid date format. Use YYYY-MM-DD format")
		return contract.BuildErrorResponse([]*contract.ResponseError{errorResp})
	}

	cashAdvance, err := s.cashAdvanceProcessor.UpdateCashAdvance(ctx, id, apctx.OrganizationID, modelReq)
	if err != nil {
		errorResp := contract.NewResponseError(constants.InternalServerErrorCode, constants.CashAdvanceServiceEntity, err.Error())
		return contract.BuildErrorResponse([]*contract.ResponseError{errorResp})
	}

	return contract.BuildSuccessResponse(transformer.CashAdvanceModelResponseToResponse(cashAdvance))
}

func (s *CashAdvanceServiceImpl) DeleteCashAdvance(ctx context.Context, apctx *appcontext.ContextInfo, id uuid.UUID) *contract.Response {
	if err := s.cashAdvanceProcessor.DeleteCashAdvance(ctx, id, apctx.OrganizationID); err != nil {
		errorResp := contract.NewResponseError(constants.InternalServerErrorCode, constants.CashAdvanceServiceEntity, err.Error())
		return contract.BuildErrorResponse([]*contract.ResponseError{errorResp})
	}

	return contract.BuildSuccessResponse(map[string]interface{}{
		"message": "Cash advance deleted successfully",
	})
}

func (s *CashAdvanceServiceImpl) GetCashAdvanceByID(ctx context.Context, apctx *appcontext.ContextInfo, id uuid.UUID) *contract.Response {
	cashAdvance, err := s.cashAdvanceProcessor.GetCashAdvanceByID(ctx, id, apctx.OrganizationID)
	if err != nil {
		errorResp := contract.NewResponseError(constants.InternalServerErrorCode, constants.CashAdvanceServiceEntity, err.Error())
		return contract.BuildErrorResponse([]*contract.ResponseError{errorResp})
	}

	return contract.BuildSuccessResponse(transformer.CashAdvanceModelResponseToResponse(cashAdvance))
}

func (s *CashAdvanceServiceImpl) ListCashAdvances(ctx context.Context, apctx *appcontext.ContextInfo, req *contract.ListCashAdvancesRequest) *contract.Response {
	modelReq := transformer.ListCashAdvancesRequestToModel(req)

	filters := make(map[string]interface{})
	if modelReq.Search != "" {
		filters["search"] = modelReq.Search
	}
	if modelReq.Status != "" {
		filters["status"] = modelReq.Status
	}
	if modelReq.SettlementStatus != "" {
		filters["settlement_status"] = modelReq.SettlementStatus
	}
	if modelReq.TeamScope != "" {
		filters["team_scope"] = modelReq.TeamScope
	}
	if modelReq.TeamCategoryID != nil {
		filters["team_category_id"] = *modelReq.TeamCategoryID
	}
	// team spells out the same two filters in one value; the validator has already
	// ruled out sending it together with them.
	switch modelReq.Team {
	case "":
	case constants.PurchaseTeamScopeCentral:
		filters["team_scope"] = constants.PurchaseTeamScopeCentral
	default:
		if teamCategoryID, err := uuid.Parse(modelReq.Team); err == nil {
			filters["team_scope"] = constants.PurchaseTeamScopeCategory
			filters["team_category_id"] = teamCategoryID
		}
	}
	if modelReq.StartDate != nil {
		filters["start_date"] = *modelReq.StartDate
	}
	if modelReq.EndDate != nil {
		filters["end_date"] = *modelReq.EndDate
	}
	// Cash belongs to the drawer it came out of, so a user signed in to one outlet
	// only sees that outlet's cash advances.
	if outletID := outletFromContext(apctx); outletID != nil {
		filters["outlet_id"] = *outletID
	}

	cashAdvances, totalPages, err := s.cashAdvanceProcessor.ListCashAdvances(ctx, apctx.OrganizationID, filters, modelReq.Page, modelReq.Limit)
	if err != nil {
		errorResp := contract.NewResponseError(constants.InternalServerErrorCode, constants.CashAdvanceServiceEntity, err.Error())
		return contract.BuildErrorResponse([]*contract.ResponseError{errorResp})
	}

	responses := make([]contract.CashAdvanceResponse, len(cashAdvances))
	for i, cashAdvance := range cashAdvances {
		if response := transformer.CashAdvanceModelResponseToResponse(cashAdvance); response != nil {
			responses[i] = *response
		}
	}

	return contract.BuildSuccessResponse(contract.ListCashAdvancesResponse{
		CashAdvances: responses,
		TotalCount:   len(responses),
		Page:         modelReq.Page,
		Limit:        modelReq.Limit,
		TotalPages:   totalPages,
	})
}

func (s *CashAdvanceServiceImpl) UpdateCashAdvanceStatus(ctx context.Context, apctx *appcontext.ContextInfo, id uuid.UUID, status string) *contract.Response {
	cashAdvance, err := s.cashAdvanceProcessor.UpdateCashAdvanceStatus(ctx, id, apctx.OrganizationID, status)
	if err != nil {
		errorResp := contract.NewResponseError(constants.InternalServerErrorCode, constants.CashAdvanceServiceEntity, err.Error())
		return contract.BuildErrorResponse([]*contract.ResponseError{errorResp})
	}

	return contract.BuildSuccessResponse(transformer.CashAdvanceModelResponseToResponse(cashAdvance))
}

func (s *CashAdvanceServiceImpl) ListCashAdvanceTeams(ctx context.Context, apctx *appcontext.ContextInfo) *contract.Response {
	teams, err := s.cashAdvanceProcessor.ListCashAdvanceTeams(ctx, apctx.OrganizationID, outletFromContext(apctx))
	if err != nil {
		errorResp := contract.NewResponseError(constants.InternalServerErrorCode, constants.CashAdvanceServiceEntity, err.Error())
		return contract.BuildErrorResponse([]*contract.ResponseError{errorResp})
	}

	return contract.BuildSuccessResponse(transformer.ListPurchaseTeamsModelResponseToResponse(teams))
}

// outletFromContext reads the caller's outlet as an optional value: an organization
// level user has none, and uuid.Nil is how that arrives on the context.
func outletFromContext(apctx *appcontext.ContextInfo) *uuid.UUID {
	if apctx.OutletID == uuid.Nil {
		return nil
	}

	outletID := apctx.OutletID
	return &outletID
}