package workflow

import (
	"errors"
	"fmt"
	"time"

	"cloud.o-forge.io/core/oc-lib/models/collaborative_area/shallow_collaborative_area"
	"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"
	"cloud.o-forge.io/core/oc-lib/models/utils"
	"cloud.o-forge.io/core/oc-lib/models/workflow/graph"
	"cloud.o-forge.io/core/oc-lib/tools"
)

/*
* AbstractWorkflow is a struct that represents a workflow for resource or native workflow
* Warning: there is 2 types of workflows, the resource workflow and the native workflow
* native workflow is the one that you create to schedule an execution
* resource workflow is the one that is created to set our native workflow in catalog
 */
type AbstractWorkflow struct {
	resources.ResourceSet
	Graph          *graph.Graph `bson:"graph,omitempty" json:"graph,omitempty"` // Graph UI & logic representation of the workflow
	ScheduleActive bool         `json:"schedule_active" bson:"schedule_active"` // ScheduleActive is a flag that indicates if the schedule is active, if not the workflow is not scheduled and no execution or booking will be set
	// Schedule       *WorkflowSchedule `bson:"schedule,omitempty" json:"schedule,omitempty"` // Schedule is the schedule of the workflow
	Shared []string `json:"shared,omitempty" bson:"shared,omitempty"` // Shared is the ID of the shared workflow
}

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

func (w *AbstractWorkflow) GetGraphItems(f func(item graph.GraphItem) bool) (list_datas []graph.GraphItem) {
	for _, item := range w.Graph.Items {
		if f(item) {
			list_datas = append(list_datas, item)
		}
	}
	return
}

func (w *AbstractWorkflow) GetResources(f func(item graph.GraphItem) bool) map[string]resources.ResourceInterface {
	list_datas := map[string]resources.ResourceInterface{}
	for _, item := range w.Graph.Items {
		if f(item) {
			_, res := item.GetResource()
			list_datas[res.GetID()] = res
		}
	}
	return list_datas
}

func (w *AbstractWorkflow) GetPricedItem(f func(item graph.GraphItem) bool, request *tools.APIRequest) map[string]pricing.PricedItemITF {
	list_datas := map[string]pricing.PricedItemITF{}
	for _, item := range w.Graph.Items {
		if f(item) {
			dt, res := item.GetResource()
			ord := res.ConvertToPricedResource(dt, request)
			list_datas[res.GetID()] = ord
		}
	}
	return list_datas
}

func (w *AbstractWorkflow) GetByRelatedProcessing(processingID string, g func(item graph.GraphItem) bool) []resources.ResourceInterface {
	storages := []resources.ResourceInterface{}
	for _, link := range w.Graph.Links {
		nodeID := link.Destination.ID
		var node resources.ResourceInterface
		if g(w.Graph.Items[link.Source.ID]) {
			item := w.Graph.Items[link.Source.ID]
			_, node = item.GetResource()
		}
		if node == nil && g(w.Graph.Items[link.Destination.ID]) { // if the source is not a storage, we consider that the destination is the storage
			nodeID = link.Source.ID
			item := w.Graph.Items[link.Destination.ID] // and the processing is the source
			_, node = item.GetResource()               // we are looking for the storage as destination
		}
		if processingID == nodeID && node != nil { // if the storage is linked to the processing
			storages = append(storages, node)
		}
	}
	return storages
}

func (wf *AbstractWorkflow) IsProcessing(item graph.GraphItem) bool {
	return item.Processing != nil
}

func (wf *AbstractWorkflow) IsCompute(item graph.GraphItem) bool {
	return item.Compute != nil
}

func (wf *AbstractWorkflow) IsData(item graph.GraphItem) bool {
	return item.Data != nil
}

func (wf *AbstractWorkflow) IsStorage(item graph.GraphItem) bool {
	return item.Storage != nil
}

func (wf *AbstractWorkflow) IsWorkflow(item graph.GraphItem) bool {
	return item.Workflow != nil
}

/*
* Workflow is a struct that represents a workflow
* it defines the native workflow
 */
type Workflow struct {
	utils.AbstractObject // AbstractObject contains the basic fields of an object (id, name)
	AbstractWorkflow     // AbstractWorkflow contains the basic fields of a workflow
}

func (w *Workflow) getPricedItem(item graph.GraphItem, request *tools.APIRequest) pricing.PricedItemITF {
	dt, res := item.GetResource()
	if dt == tools.INVALID {
		return nil
	}
	return res.ConvertToPricedResource(dt, request)
}

func (ao *Workflow) VerifyAuth(request *tools.APIRequest) bool {
	isAuthorized := false
	if len(ao.Shared) > 0 {
		for _, shared := range ao.Shared {
			shared, code, _ := shallow_collaborative_area.NewAccessor(request).LoadOne(shared)
			if code != 200 || shared == nil {
				isAuthorized = false
			}
			isAuthorized = shared.VerifyAuth(request)
		}
	}
	return ao.AbstractObject.VerifyAuth(request) || isAuthorized
}

/*
* CheckBooking is a function that checks the booking of the workflow on peers (even ourselves)
 */
func (wfa *Workflow) CheckBooking(caller *tools.HTTPCaller) (bool, error) {
	// check if
	if wfa.Graph == nil { // no graph no booking
		return false, nil
	}
	accessor := (&resources.ComputeResource{}).GetAccessor(&tools.APIRequest{Caller: caller})
	for _, link := range wfa.Graph.Links {
		if ok, compute_id := link.IsComputeLink(*wfa.Graph); ok { // check if the link is a link between a compute and a resource
			compute, code, _ := accessor.LoadOne(compute_id)
			if code != 200 {
				continue
			}
			// CHECK BOOKING ON PEER, compute could be a remote one
			peerID := compute.(*resources.ComputeResource).CreatorID
			if peerID == "" {
				return false, errors.New("no peer id")
			} // no peer id no booking, we need to know where to book
			_, err := (&peer.Peer{}).LaunchPeerExecution(peerID, compute_id, tools.BOOKING, tools.GET, nil, caller)
			if err != nil {
				return false, err
			}
		}
	}
	return true, nil
}

func (wf *Workflow) Planify(start time.Time, end *time.Time, request *tools.APIRequest) (float64, map[tools.DataType][]pricing.PricedItemITF, *Workflow, error) {
	processings := []*resources.ProcessingResource{}
	priceds := map[tools.DataType][]pricing.PricedItemITF{}
	priceds[tools.PROCESSING_RESOURCE] = []pricing.PricedItemITF{}
	for _, item := range wf.GetGraphItems(wf.IsProcessing) {
		dt, realItem := item.GetResource()
		if realItem == nil {
			return 0, priceds, nil, errors.New("could not load the processing resource")
		}
		priced := realItem.ConvertToPricedResource(dt, request)
		timeFromStartS := wf.Graph.GetAverageTimeProcessingBeforeStart(0, realItem.GetID(), request)
		started := start.Add(time.Duration(timeFromStartS) * time.Second)
		priced.SetLocationStart(started)
		priced.SetLocationEnd(started.Add(time.Duration(priced.GetExplicitDurationInS())))
		processings = append(processings, realItem.(*resources.ProcessingResource))
		priceds[tools.PROCESSING_RESOURCE] = append(priceds[tools.PROCESSING_RESOURCE], priced)
	}
	priceds[tools.DATA_RESOURCE] = []pricing.PricedItemITF{}
	for _, item := range wf.GetGraphItems(wf.IsData) {
		dt, realItem := item.GetResource()
		if realItem == nil {
			continue
		}
		priced := realItem.ConvertToPricedResource(dt, request)
		priced.SetLocationStart(start)
		priced.SetLocationEnd(*end)
		priceds[tools.PROCESSING_RESOURCE] = append(priceds[tools.PROCESSING_RESOURCE], priced)
	}
	for _, f := range []func(graph.GraphItem) bool{wf.IsStorage, wf.IsCompute} {
		for _, item := range wf.GetGraphItems(f) {
			dt, r := item.GetResource()
			if r == nil {
				continue
			}
			if priceds[dt] == nil {
				priceds[dt] = []pricing.PricedItemITF{}
			}
			priced := r.ConvertToPricedResource(dt, request)
			nearestStart, longestDuration := wf.Graph.GetAverageTimeRelatedToProcessingActivity(start, processings, r,
				func(i graph.GraphItem) resources.ResourceInterface {
					if f(i) {
						_, r := i.GetResource()
						return r
					} else {
						return nil
					}
				}, request)
			started := start.Add(time.Duration(nearestStart) * time.Second)
			priced.SetLocationStart(started)
			if longestDuration >= 0 {
				priced.SetLocationEnd(started.Add(time.Duration(longestDuration)))
			}
			priceds[dt] = append(priceds[dt], priced)
		}
	}
	longest := wf.getLongestTime(end, priceds, request)
	priceds[tools.WORKFLOW_RESOURCE] = []pricing.PricedItemITF{}
	for _, item := range wf.GetGraphItems(wf.IsWorkflow) {
		access := NewAccessor(nil)
		_, r := item.GetResource()
		if r == nil {
			return 0, priceds, nil, errors.New("could not load the workflow")
		}
		priced := r.ConvertToPricedResource(tools.WORKFLOW_RESOURCE, request)
		res, code, err := access.LoadOne(r.GetID())
		if code != 200 || err != nil {
			return 0, priceds, nil, errors.New("could not load the workflow with id: " + fmt.Sprintf("%v", err.Error()))
		}
		neoLongest := float64(0)
		innerWF := res.(*Workflow)
		neoLongest, _, innerWF, err = innerWF.Planify(start, end, request)
		if neoLongest > longest {
			longest = neoLongest
		}
		started := start.Add(time.Duration(wf.getNearestStart(start, priceds, request)) * time.Second)
		priced.SetLocationStart(started)
		durationE := time.Duration(longest)
		if durationE < 0 {
			continue
		}
		ended := start.Add(durationE * time.Second)
		priced.SetLocationEnd(ended)
		priceds[tools.WORKFLOW_RESOURCE] = append(priceds[tools.WORKFLOW_RESOURCE], priced)
	}
	return longest, priceds, wf, nil
}

func (wf *Workflow) getNearestStart(start time.Time, priceds map[tools.DataType][]pricing.PricedItemITF, request *tools.APIRequest) float64 {
	near := float64(10000000000)
	for _, items := range priceds {
		for _, priced := range items {
			if priced.GetLocationStart() == nil {
				continue
			}
			newS := priced.GetLocationStart()
			if newS.Sub(start).Seconds() < near {
				near = newS.Sub(start).Seconds()
			}
		}
		// get the nearest start from start var
	}
	return near
}

func (wf *Workflow) getLongestTime(end *time.Time, priceds map[tools.DataType][]pricing.PricedItemITF, request *tools.APIRequest) float64 {
	if end == nil {
		return -1
	}
	longestTime := float64(0)
	for _, priced := range priceds[tools.PROCESSING_RESOURCE] {
		if priced.GetLocationEnd() == nil {
			continue
		}
		newS := priced.GetLocationEnd()
		if longestTime < newS.Sub(*end).Seconds() {
			longestTime = newS.Sub(*end).Seconds()
		}
		// get the nearest start from start var
	}
	return longestTime
}