package publisher

import (
	"git.aiterp.net/lucifer/new-server/models"
	"time"
)

type Scene struct {
	data       *models.Scene
	group      string
	startTime  time.Time
	endTime    time.Time
	roleMap    map[int]int
	roleList   map[int][]models.Device
	lastStates map[int]models.DeviceState

	due          bool
	lastInterval int64
}

// UpdateScene updates the scene data and re-seats all devices.
func (s *Scene) UpdateScene(data models.Scene) {
	devices := make([]models.Device, 0, 16)

	// Collect all devices into the undefined role (-1)
	for _, list := range s.roleList {
		for _, device := range list {
			devices = append(devices, device)
			s.roleMap[device.ID] = -1
		}
	}
	s.roleList = map[int][]models.Device{-1: devices}

	// Update data and reset devices.
	s.data = &data
	for _, device := range append(devices[:0:0], devices...) {
		s.UpsertDevice(device)
	}
}

// UpsertDevice moves the device if necessary and updates its state.
func (s *Scene) UpsertDevice(device models.Device) {
	if s.data == nil {
		s.roleMap[device.ID] = -1
		s.roleList[-1] = append(s.roleList[-1], device)
		return
	}

	oldIndex, hasOldIndex := s.roleMap[device.ID]
	newIndex := s.data.RoleIndex(&device)

	s.roleMap[device.ID] = newIndex

	if hasOldIndex {
		for i, device2 := range s.roleList[oldIndex] {
			if device2.ID == device.ID {
				s.roleList[oldIndex] = append(s.roleList[oldIndex][:i], s.roleList[oldIndex][i+1:]...)
				break
			}
		}
	}

	s.due = true

	s.roleList[newIndex] = append(s.roleList[newIndex], device)
	if newIndex != -1 {
		s.data.Roles[newIndex].ApplyOrder(s.roleList[newIndex])
	}
}

// RemoveDevice finds and remove a device. It's a noop if the device does not exist in this scene.
func (s *Scene) RemoveDevice(device models.Device) {
	roleIndex, hasRoleIndex := s.roleMap[device.ID]
	if !hasRoleIndex {
		return
	}

	for i, device2 := range s.roleList[roleIndex] {
		if device2.ID == device.ID {
			s.roleList[roleIndex] = append(s.roleList[roleIndex][:i], s.roleList[roleIndex][i+1:]...)
			break
		}
	}

	s.due = true

	delete(s.roleMap, device.ID)
	delete(s.lastStates, device.ID)
}

func (s *Scene) Empty() bool {
	for _, list := range s.roleList {
		if len(list) > 0 {
			return false
		}
	}

	return true
}

func (s *Scene) Due() bool {
	if s.due {
		return true
	}

	if s.data.IntervalMS > 0 {
		interval := time.Duration(s.data.IntervalMS) * time.Millisecond
		return int64(time.Since(s.startTime)/interval) != s.lastInterval
	}

	return false
}

func (s *Scene) UnaffectedDevices() []models.Device {
	return append(s.roleList[-1][:0:0], s.roleList[-1]...)
}

func (s *Scene) AllDevices() []models.Device {
	res := make([]models.Device, 0, 16)
	for _, list := range s.roleList {
		res = append(res, list...)
	}

	return res
}

// Run runs the scene
func (s *Scene) Run() []models.Device {
	if s.data == nil {
		return []models.Device{}
	}

	intervalNumber := int64(0)
	intervalMax := int64(1)
	if s.data.IntervalMS > 0 {
		interval := time.Duration(s.data.IntervalMS) * time.Millisecond
		intervalNumber = int64(time.Since(s.startTime) / interval)

		if !s.endTime.IsZero() {
			intervalMax = int64(s.endTime.Sub(s.startTime) / interval)
		} else {
			intervalMax = intervalNumber + 1
		}
	}

	updatedDevices := make([]models.Device, 0, 16)
	for i, list := range s.roleList {
		if i == -1 {
			continue
		}

		role := s.data.Roles[i]

		for j, device := range list {
			newState := role.ApplyEffect(&device, models.SceneRunContext{
				Index:          j,
				Length:         len(list),
				IntervalNumber: intervalNumber,
				IntervalMax:    intervalMax,
			})

			err := device.SetState(newState)
			if err != nil {
				continue
			}

			s.lastStates[device.ID] = device.State

			updatedDevices = append(updatedDevices, device)
		}
	}

	s.due = false
	s.lastInterval = intervalNumber

	return updatedDevices
}

func (s *Scene) LastState(id int) *models.DeviceState {
	lastState, ok := s.lastStates[id]
	if !ok {
		return nil
	}

	return &lastState
}