package devices

import (
	"context"
	"xiaomihome/xiaomi"
)

// Vacuum 扫地机统一控制接口
type Vacuum interface {
	Device
	Start(ctx context.Context) error
	Stop(ctx context.Context) error
	ReturnToDock(ctx context.Context) error
	SetFanLevel(ctx context.Context, level int) error
	GetFanLevel(ctx context.Context) (int, error)
	GetStatus(ctx context.Context) (VacuumStatus, error)

	OnStateChanged(handler func(state VacuumStatus, changed string)) (string, error)
	GetState() VacuumStatus
	FetchState(ctx context.Context) (VacuumStatus, error)
}

// VacuumStatus 扫地机运行状态（字段名对齐 SPEC type）
type VacuumStatus struct {
	On       bool `json:"on"`
	Mode     int  `json:"mode"`
	FanLevel int  `json:"fanLevel"`
	Battery  int  `json:"battery"`
}

type vacuumDevice struct {
	BaseDevice
	propOn       siidPiid
	propMode     siidPiid
	propFanLevel siidPiid
	propBattery  siidPiid
	stateCache   VacuumStatus
}

func NewVacuum(client *xiaomi.Client, info *xiaomi.DeviceInfo) (Vacuum, error) {
	d := &vacuumDevice{BaseDevice: NewBaseDevice(client, info)}
	resolver := d.getSpecResolver()
	if resolver == nil { return nil, xiaomi.ErrNoSPEC }
	siid, piid, ok := resolver.find("on")
	if !ok { return nil, xiaomi.ErrNotSupported }
	d.propOn = siidPiid{siid, piid, true}
	if s, p, ok := resolver.find("mode"); ok { d.propMode = siidPiid{s, p, true} }
	if s, p, ok := resolver.find("fan-level"); ok { d.propFanLevel = siidPiid{s, p, true} }
	if s, p, ok := resolver.find("battery-level"); ok { d.propBattery = siidPiid{s, p, true} }
	return d, nil
}

func (d *vacuumDevice) Start(ctx context.Context) error {
	_, err := d.Action(ctx, d.propOn.siid, 1, nil)
	return err
}
func (d *vacuumDevice) Stop(ctx context.Context) error {
	_, err := d.Action(ctx, d.propOn.siid, 0, nil)
	return err
}
func (d *vacuumDevice) ReturnToDock(ctx context.Context) error {
	_, err := d.Action(ctx, d.propOn.siid, 2, nil)
	return err
}
func (d *vacuumDevice) SetFanLevel(ctx context.Context, level int) error {
	if !d.propFanLevel.valid { return xiaomi.ErrNotSupported }
	return d.SetProp(ctx, d.propFanLevel.siid, d.propFanLevel.piid, level)
}
func (d *vacuumDevice) GetFanLevel(ctx context.Context) (int, error) {
	if !d.propFanLevel.valid { return 0, xiaomi.ErrNotSupported }
	prop, err := d.GetProp(ctx, d.propFanLevel.siid, d.propFanLevel.piid)
	if err != nil { return 0, err }
	return toInt(prop.Value), nil
}
func (d *vacuumDevice) GetStatus(ctx context.Context) (VacuumStatus, error) {
	// 云端实时查询
	keys := []xiaomi.PropKey{}
	add := func(sp siidPiid) {
		if sp.valid { keys = append(keys, xiaomi.PropKey{DID: d.info.DID, SIID: sp.siid, PIID: sp.piid}) }
	}
	add(d.propOn); add(d.propMode); add(d.propFanLevel); add(d.propBattery)
	props, err := d.client.GetProps(ctx, keys)
	if err != nil { return VacuumStatus{}, err }
	status := VacuumStatus{}
	for _, p := range props {
		switch {
		case d.propOn.valid && p.SIID == d.propOn.siid && p.PIID == d.propOn.piid:
			status.On, _ = p.Value.(bool)
		case d.propMode.valid && p.SIID == d.propMode.siid && p.PIID == d.propMode.piid:
			status.Mode = toInt(p.Value)
		case d.propFanLevel.valid && p.SIID == d.propFanLevel.siid && p.PIID == d.propFanLevel.piid:
			status.FanLevel = toInt(p.Value)
		case d.propBattery.valid && p.SIID == d.propBattery.siid && p.PIID == d.propBattery.piid:
			status.Battery = toInt(p.Value)
		}
	}
	return status, nil
}

func (d *vacuumDevice) OnStateChanged(handler func(state VacuumStatus, changed string)) (string, error) {
	type field struct{ siid, piid int; name string; fill func(*VacuumStatus, interface{}) }
	var fields []field
	if d.propOn.valid {
		fields = append(fields, field{d.propOn.siid, d.propOn.piid, "on", func(s *VacuumStatus, v interface{}) { s.On, _ = v.(bool) }})
	}
	if d.propMode.valid {
		fields = append(fields, field{d.propMode.siid, d.propMode.piid, "mode", func(s *VacuumStatus, v interface{}) { s.Mode = toInt(v) }})
	}
	if d.propFanLevel.valid {
		fields = append(fields, field{d.propFanLevel.siid, d.propFanLevel.piid, "fan-level", func(s *VacuumStatus, v interface{}) { s.FanLevel = toInt(v) }})
	}
	if d.propBattery.valid {
		fields = append(fields, field{d.propBattery.siid, d.propBattery.piid, "battery", func(s *VacuumStatus, v interface{}) { s.Battery = toInt(v) }})
	}
	if len(fields) == 0 { return "", xiaomi.ErrNotSupported }
	return d.SubProp(0, 0, func(did string, prop *xiaomi.PropertyValue) {
		for _, f := range fields {
			if f.siid == prop.SIID && f.piid == prop.PIID {
				f.fill(&d.stateCache, prop.Value)
				handler(d.stateCache, f.name)
				return
			}
		}
	})
}

func (d *vacuumDevice) GetState() VacuumStatus { return d.stateCache }
func (d *vacuumDevice) FetchState(ctx context.Context) (VacuumStatus, error) {
	status, err := d.GetStatus(ctx)
	if err != nil { return d.stateCache, err }
	d.stateCache = status
	return status, nil
}