package main

import (
	"powerpod/gotool/pb"
)

const (
	lipoMinMv = 3000
	lipoMaxMv = 4200
)

type lipoReadingJSON struct {
	Valid     bool   `json:"valid"`
	VoltageMv uint32 `json:"voltage_mv"`
	Percent   int    `json:"percent,omitempty"`
}

type batterySampleJSON struct {
	ClientID uint32          `json:"client_id"`
	Lipo1    lipoReadingJSON `json:"lipo1"`
	Lipo2    lipoReadingJSON `json:"lipo2"`
	AgeMs    uint32          `json:"age_ms,omitempty"`
}

type batteryAPIRequest struct {
	ClientID   uint32 `json:"client_id"`
	AllClients bool   `json:"all_clients"`
}

type batteryAPIResponse struct {
	Type     string              `json:"type,omitempty"` // battery_status (WebSocket)
	Success  bool                `json:"success"`
	Samples  []batterySampleJSON `json:"samples,omitempty"`
	Error    string              `json:"error,omitempty"`
}

func lipoPercent(mv uint32) int {
	if mv <= lipoMinMv {
		return 0
	}
	if mv >= lipoMaxMv {
		return 100
	}
	return int((mv - lipoMinMv) * 100 / (lipoMaxMv - lipoMinMv))
}

func lipoFromPBMsg(l *pb.LipoReading) lipoReadingJSON {
	if l == nil {
		return lipoReadingJSON{}
	}
	return lipoFromPB(l.GetValid(), l.GetVoltageMv())
}

func lipoFromPB(valid bool, mv uint32) lipoReadingJSON {
	out := lipoReadingJSON{Valid: valid, VoltageMv: mv}
	if valid {
		out.Percent = lipoPercent(mv)
	}
	return out
}

func batterySamplesFromPB(samples []*pb.BatterySample) []batterySampleJSON {
	out := make([]batterySampleJSON, 0, len(samples))
	for _, s := range samples {
		out = append(out, batterySampleJSON{
			ClientID: s.GetClientId(),
			Lipo1:    lipoFromPBMsg(s.GetLipo1()),
			Lipo2:    lipoFromPBMsg(s.GetLipo2()),
			AgeMs:    s.GetAgeMs(),
		})
	}
	return out
}

func applyBatteryStatus(link *managedSerial, in batteryAPIRequest) batteryAPIResponse {
	resp, err := link.BatteryStatus(&pb.BatteryStatusRequest{
		ClientId:   in.ClientID,
		AllClients: in.AllClients,
	})
	if err != nil {
		return batteryAPIResponse{Error: err.Error()}
	}
	samples := batterySamplesFromPB(resp.GetSamples())
	out := batteryAPIResponse{
		Success: resp.GetSuccess() || len(samples) > 0,
		Samples: samples,
	}
	if len(samples) == 0 && out.Error == "" {
		out.Error = "battery status unavailable"
	}
	return out
}

func findBatterySample(samples []batterySampleJSON, clientID uint32) (batterySampleJSON, bool) {
	for _, s := range samples {
		if s.ClientID == clientID {
			return s, true
		}
	}
	return batterySampleJSON{}, false
}

// applyBatterySamplesToState merges UART/REST battery samples into dashboard views.
func applyBatterySamplesToState(st *DashboardState, samples []batterySampleJSON) {
	if st == nil || len(samples) == 0 {
		return
	}
	if m, ok := findBatterySample(samples, 0); ok {
		st.Master.Lipo1 = m.Lipo1
		st.Master.Lipo2 = m.Lipo2
		st.Master.BatteryAgeMs = m.AgeMs
	}
	for i := range st.Clients {
		if s, ok := findBatterySample(samples, st.Clients[i].ID); ok {
			st.Clients[i].Lipo1 = s.Lipo1
			st.Clients[i].Lipo2 = s.Lipo2
			st.Clients[i].BatteryAgeMs = s.AgeMs
		}
	}
}