package mill

import (
	"errors"
	lucifer3 "git.aiterp.net/lucifer3/server"
	"git.aiterp.net/lucifer3/server/commands"
	"git.aiterp.net/lucifer3/server/device"
	"git.aiterp.net/lucifer3/server/events"
	"sync"
)

func NewService() lucifer3.ActiveService {
	return &service{
		bridges: make([]Bridge, 0, 8),
	}
}

type service struct {
	mu sync.Mutex

	bridges []Bridge
}

func (s *service) Active() bool {
	return true
}

func (s *service) HandleEvent(*lucifer3.EventBus, lucifer3.Event) {
	// NOP
}

func (s *service) HandleCommand(bus *lucifer3.EventBus, command lucifer3.Command) {
	defer s.mu.Unlock()
	s.mu.Lock()

	switch cmd := command.(type) {
	case commands.PairDevice:
		// Only mill
		if _, ok := cmd.Matches("mill"); !ok {
			return
		}

		// Run connection if needed
		err := s.connect(bus, cmd.ID, &cmd.APIKey, nil)
		if err != nil {
			bus.RunEvent(events.DeviceFailed{
				ID:    cmd.ID,
				Error: err.Error(),
			})
			return
		}

		// Connection successful
		bus.RunEvent(events.DeviceAccepted{
			ID:     cmd.ID,
			APIKey: cmd.APIKey,
		})
	case commands.ConnectDevice:
		// Connect if necessary
		err := s.connect(bus, cmd.ID, &cmd.APIKey, nil)
		if err != nil {
			bus.RunEvent(events.DeviceFailed{
				ID:    cmd.ID,
				Error: err.Error(),
			})
			return
		}
	case commands.SetState:
		err := s.connect(bus, cmd.ID, nil, &cmd.State)
		if err != nil {
			bus.RunEvent(events.DeviceFailed{
				ID:    cmd.ID,
				Error: err.Error(),
			})
			return
		}
	case commands.SetStateBatch:
		for id, state := range cmd {
			err := s.connect(bus, id, nil, &state)
			if err != nil {
				bus.RunEvent(events.DeviceFailed{
					ID:    id,
					Error: err.Error(),
				})
				return
			}
		}
	}
}

func (s *service) connect(
	bus *lucifer3.EventBus,
	id string,
	apiKey *string,
	state *device.State,
) error {
	hasState := state != nil
	if !hasState {
		state = &device.State{}
	}

	// Check if connection is active
	for _, bridge := range s.bridges {
		// Don't block with dead bridges
		if !bridge.IsStarted() {
			continue
		}

		// Setting a dummy state to the bridge to check if it's online
		bridge.SetBus(bus)
		if ok := bridge.SetState(id, *state); ok {
			return nil
		}
	}

	if apiKey == nil {
		return errors.New("not connected to device " + id)
	}

	// Make a bridge, if not a mill ID, this will return ok false
	bridge, ok := MakeBridge(id, *apiKey)
	if !ok {
		return nil
	}

	bridge.SetBus(bus)

	// Start bridge, and throw error if it failed to start
	bridge.Start()
	if !bridge.IsStarted() {
		return errors.New("failed to connect to " + id)
	}

	// Add bridge to lists
	s.bridges = append(s.bridges, bridge)

	// Update state, if needed, after first connection
	if hasState {
		if ok := bridge.SetState(id, *state); !ok {
			return errors.New("unable to set state to " + id + " after connecting")
		}
	}

	return nil
}