package order

import (
	"errors"
	"fmt"
	"sync"
	"time"

	"cloud.o-forge.io/core/oc-lib/dbs"
	"cloud.o-forge.io/core/oc-lib/models/booking"
	"cloud.o-forge.io/core/oc-lib/models/common/pricing"
	"cloud.o-forge.io/core/oc-lib/models/peer"
	"cloud.o-forge.io/core/oc-lib/models/resources/purchase_resource"
	"cloud.o-forge.io/core/oc-lib/models/utils"
	"cloud.o-forge.io/core/oc-lib/models/workflow_execution"
	"cloud.o-forge.io/core/oc-lib/tools"
)

/*
* Booking is a struct that represents a booking
 */

type OrderStatus = int

const (
	DRAFT OrderStatus = iota
	PENDING
	CANCELLED
	PARTIAL
	PAID
	DISPUTED
	OVERDUE
	REFUND
)

type Order struct {
	utils.AbstractObject
	OrderBy              string                `json:"order_by" bson:"order_by" validate:"required"`
	WorkflowExecutionIDs []string              `json:"workflow_execution_ids" bson:"workflow_execution_ids" validate:"required"`
	Status               OrderStatus           `json:"status" bson:"status" default:"0"`
	SubOrders            map[string]*PeerOrder `json:"sub_orders" bson:"sub_orders"`
	Total                float64               `json:"total" bson:"total" validate:"required"`
}

func (r *Order) StoreDraftDefault() {
	r.IsDraft = true
}

func (r *Order) CanUpdate(set utils.DBObject) (bool, utils.DBObject) {
	if !r.IsDraft && r.Status != set.(*Order).Status {
		return true, &Order{Status: set.(*Order).Status} // only state can be updated
	}
	return r.IsDraft, set
}

func (r *Order) CanDelete() bool {
	return r.IsDraft // only draft order can be deleted
}

func (o *Order) DraftOrder(scheduler *workflow_execution.WorkflowSchedule, request *tools.APIRequest) error {
	// set the draft order from the model
	if err := o.draftStoreFromModel(scheduler, request); err != nil {
		return err
	}
	return nil
}

func (o *Order) Pay(scheduler *workflow_execution.WorkflowSchedule, request *tools.APIRequest) error {
	if _, err := o.draftBookOrder(scheduler, request); err != nil {
		return err
	}
	o.Status = PENDING
	_, code, err := o.GetAccessor(request).UpdateOne(o, o.GetID())
	if code != 200 || err != nil {
		return errors.New("could not update the order" + fmt.Sprintf("%v", err))
	}
	if err := o.pay(request); err != nil { // pay the order
		return err
	} else {
		o.IsDraft = false
	}
	for _, exec := range scheduler.WorkflowExecutions {
		exec.IsDraft = false
		_, code, err := utils.GenericUpdateOne(exec, exec.GetID(),
			workflow_execution.NewAccessor(request), &workflow_execution.WorkflowExecutions{})
		if code != 200 || err != nil {
			return errors.New("could not update the workflow execution" + fmt.Sprintf("%v", err))
		}
	}
	_, code, err = o.GetAccessor(request).UpdateOne(o, o.GetID())
	if code != 200 || err != nil {
		return errors.New("could not update the order" + fmt.Sprintf("%v", err))
	}
	/*
		TODO : TEMPORARY SET BOOKINGS TO UNDRAFT TO AVOID DELETION
		BUT NEXT ONLY WHO IS PAYED WILL BE ALLOWED TO CHANGE IT
	*/
	return nil
}

func (o *Order) draftStoreFromModel(scheduler *workflow_execution.WorkflowSchedule, request *tools.APIRequest) error {
	if request == nil {
		return errors.New("no request found")
	}
	if scheduler.Workflow.Graph == nil { // if the workflow has no graph, return an error
		return errors.New("no graph found")
	}
	o.SetName()
	o.IsDraft = true
	o.OrderBy = request.Username
	o.WorkflowExecutionIDs = []string{} // create an array of ids
	for _, exec := range scheduler.WorkflowExecutions {
		o.WorkflowExecutionIDs = append(o.WorkflowExecutionIDs, exec.GetID())
	}
	// set the name of the order
	resourcesByPeer := map[string][]pricing.PricedItemITF{} // create a map of resources by peer

	processings := scheduler.Workflow.GetPricedItem(scheduler.Workflow.IsProcessing) // get the processing items
	datas := scheduler.Workflow.GetPricedItem(scheduler.Workflow.IsData)             // get the data items
	storages := scheduler.Workflow.GetPricedItem(scheduler.Workflow.IsStorage)       // get the storage items
	workflows := scheduler.Workflow.GetPricedItem(scheduler.Workflow.IsWorkflow)     // get the workflow items
	for _, items := range []map[string]pricing.PricedItemITF{processings, datas, storages, workflows} {
		for _, item := range items {
			if _, ok := resourcesByPeer[item.GetCreatorID()]; !ok {
				resourcesByPeer[item.GetCreatorID()] = []pricing.PricedItemITF{}
			}
			resourcesByPeer[item.GetCreatorID()] = append(resourcesByPeer[item.GetCreatorID()], item)
		}
	}
	for peerID, resources := range resourcesByPeer {
		peerOrder := &PeerOrder{
			Status: DRAFT,
			PeerID: peerID,
		}
		peerOrder.GenerateID()
		for _, resource := range resources {
			peerOrder.AddItem(resource, len(scheduler.WorkflowExecutions)) // TODO SPECIALS REF ADDITIONALS NOTES
		}
		o.SubOrders[peerOrder.GetID()] = peerOrder
	}
	// search an order with same user name and same session id
	err := o.sumUpBill(request)
	if err != nil {
		return err
	}
	// should store the order
	res, code, err := o.GetAccessor(request).Search(&dbs.Filters{
		And: map[string][]dbs.Filter{
			"order_by": {{Operator: dbs.EQUAL.String(), Value: request.Username}},
		},
	}, "", o.IsDraft)
	if code != 200 || err != nil {
		return errors.New("could not search the order" + fmt.Sprintf("%v", err))
	}
	if len(res) > 0 {
		_, code, err := utils.GenericUpdateOne(o, res[0].GetID(), o.GetAccessor(request), o)
		if code != 200 || err != nil {
			return errors.New("could not update the order" + fmt.Sprintf("%v", err))
		}
	} else {
		_, code, err := utils.GenericStoreOne(o, o.GetAccessor(request))
		if code != 200 || err != nil {
			return errors.New("could not store the order" + fmt.Sprintf("%v", err))
		}
	}
	return nil
}

func (o *Order) draftBookOrder(scheduler *workflow_execution.WorkflowSchedule, request *tools.APIRequest) ([]*booking.Booking, error) {
	draftedBookings := []*booking.Booking{}
	if request == nil {
		return draftedBookings, errors.New("no request found")
	}
	for _, exec := range scheduler.WorkflowExecutions {
		bookings := exec.Book(scheduler.Workflow)
		for _, booking := range bookings {
			_, err := (&peer.Peer{}).LaunchPeerExecution(booking.DestPeerID, "",
				tools.BOOKING, tools.POST, booking.Serialize(booking), request.Caller)
			if err != nil {
				return draftedBookings, errors.New("could not launch the peer execution : " + fmt.Sprintf("%v", err))
			}
			draftedBookings = append(draftedBookings, booking)
		}
	}
	return draftedBookings, nil
}

func (o *Order) Quantity() int {
	return len(o.WorkflowExecutionIDs)
}

func (d *Order) SetName() {
	d.Name = d.UUID + "_order_" + "_" + time.Now().UTC().Format("2006-01-02T15:04:05")
}

func (d *Order) GetAccessor(request *tools.APIRequest) utils.Accessor {
	return NewAccessor(request) // Create a new instance of the accessor
}

func (d *Order) sumUpBill(request *tools.APIRequest) error {
	for _, b := range d.SubOrders {
		err := b.SumUpBill(request)
		if err != nil {
			return err
		}
		d.Total += b.Total
	}
	return nil
}

// TO FINISH
func (d *Order) pay(request *tools.APIRequest) error {
	responses := make(chan *PeerOrder, len(d.SubOrders))
	var wg *sync.WaitGroup
	wg.Add(len(d.SubOrders))
	for _, b := range d.SubOrders {
		go b.Pay(request, responses, wg)
	}
	wg.Wait()
	errs := ""
	gotAnUnpaid := false
	count := 0
	for range responses {
		res := <-responses
		count++
		if res != nil {
			if res.Error != "" {
				errs += res.Error
			}
			if res.Status != PAID {
				gotAnUnpaid = true
			}
			d.Status = PARTIAL
			d.SubOrders[res.GetID()] = res
			if count == len(d.SubOrders) && !gotAnUnpaid {
				d.Status = PAID
			}
		}
	}

	if errs != "" {
		return errors.New(errs)
	}
	return nil
}

type PeerOrder struct {
	utils.AbstractObject
	Error          string           `json:"error,omitempty" bson:"error,omitempty"`
	PeerID         string           `json:"peer_id,omitempty" bson:"peer_id,omitempty"`
	Status         OrderStatus      `json:"status" bson:"status" default:"0"`
	BillingAddress string           `json:"billing_address,omitempty" bson:"billing_address,omitempty"`
	Items          []*PeerItemOrder `json:"items,omitempty" bson:"items,omitempty"`
	Total          float64          `json:"total,omitempty" bson:"total,omitempty"`
}

func (d *PeerOrder) Pay(request *tools.APIRequest, response chan *PeerOrder, wg *sync.WaitGroup) {
	d.Status = PENDING
	go func() {
		// DO SOMETHING TO PAY ON BLOCKCHAIN OR WHATEVER ON RETURN UPDATE STATUS
		d.Status = PAID // TO REMOVE LATER IT'S A MOCK
		if d.Status == PAID {
			for _, b := range d.Items {
				if !b.Item.IsPurchased(request) {
					continue
				}
				accessor := purchase_resource.NewAccessor(request)
				accessor.StoreOne(&purchase_resource.PurchaseResource{
					ResourceID:   b.Item.GetID(),
					ResourceType: b.Item.GetType(),
					EndDate:      b.Item.GetLocationEnd(),
				})
			}
		}

		if d.Status != PENDING {
			response <- d
		}
		wg.Done()
	}()
}

func (d *PeerOrder) SumUpBill(request *tools.APIRequest) error {
	for _, b := range d.Items {
		tot, err := b.GetPrice(request) // missing something
		if err != nil {
			return err
		}
		d.Total += tot
	}
	return nil
}

func (d *PeerOrder) AddItem(item pricing.PricedItemITF, quantity int) {
	d.Items = append(d.Items, &PeerItemOrder{
		Quantity: quantity,
		Item:     item,
	})
}

func (d *PeerOrder) SetName() {
	d.Name = d.UUID + "_order_" + d.PeerID + "_" + time.Now().UTC().Format("2006-01-02T15:04:05")
}

type PeerItemOrder struct {
	Quantity int                                `json:"quantity,omitempty" bson:"quantity,omitempty"`
	Purchase purchase_resource.PurchaseResource `json:"purchase,omitempty" bson:"purchase,omitempty"`
	Item     pricing.PricedItemITF              `json:"item,omitempty" bson:"item,omitempty"`
}

func (d *PeerItemOrder) GetPrice(request *tools.APIRequest) (float64, error) {
	accessor := purchase_resource.NewAccessor(request)
	search, code, _ := accessor.Search(&dbs.Filters{
		And: map[string][]dbs.Filter{
			"resource_id": {{Operator: dbs.EQUAL.String(), Value: d.Item.GetID()}},
		},
	}, "", d.Purchase.IsDraft)
	if code == 200 && len(search) > 0 {
		for _, s := range search {
			if s.(*purchase_resource.PurchaseResource).EndDate == nil || time.Now().UTC().After(*s.(*purchase_resource.PurchaseResource).EndDate) {
				return 0, nil
			}
		}
	}
	p, err := d.Item.GetPrice(request)
	if err != nil {
		return 0, err
	}
	return p * float64(d.Quantity), nil
}

// SHOULD SET A BUYING STATUS WHEN PAYMENT IS VALIDATED