package main

import (
	"encoding/json"
	"net/http"

	pb "powerpod/gotool/pb"
)

type inputSendModeAPIResponse struct {
	Success       bool   `json:"success"`
	Mode          uint32 `json:"mode"`
	ModeName      string `json:"mode_name"`
	ClientID      uint32 `json:"client_id,omitempty"`
	SlavesUpdated uint32 `json:"slaves_updated,omitempty"`
	Error         string `json:"error,omitempty"`
}

func inputSendModeName(mode pb.InputSendMode) string {
	switch mode {
	case pb.InputSendMode_INPUT_SEND_BEST_EFFORT:
		return "best_effort"
	case pb.InputSendMode_INPUT_SEND_FAST:
		return "fast"
	case pb.InputSendMode_INPUT_SEND_WAIT:
		return "wait"
	case pb.InputSendMode_INPUT_SEND_RELIABLE:
		return "reliable"
	default:
		return "unknown"
	}
}

func mountInputSendModeAPI(mux *http.ServeMux, link *managedSerial) {
	mux.HandleFunc("/api/input-send-mode", func(w http.ResponseWriter, r *http.Request) {
		switch r.Method {
		case http.MethodGet:
			serveInputSendModeGet(w, link)
		case http.MethodPut, http.MethodPost:
			serveInputSendModePut(w, r, link)
		default:
			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
		}
	})
}

func serveInputSendModeGet(w http.ResponseWriter, link *managedSerial) {
	resp, err := link.InputSendMode(&pb.InputSendModeRequest{Write: false})
	if err != nil {
		writeJSON(w, http.StatusBadGateway, inputSendModeAPIResponse{Error: err.Error()})
		return
	}
	writeJSON(w, http.StatusOK, inputSendModeAPIResponse{
		Success:  resp.GetSuccess(),
		Mode:     uint32(resp.GetMode()),
		ModeName: inputSendModeName(resp.GetMode()),
	})
}

func serveInputSendModePut(w http.ResponseWriter, r *http.Request, link *managedSerial) {
	var body struct {
		Mode       uint32 `json:"mode"`
		ClientID   uint32 `json:"client_id"`
		AllClients bool   `json:"all_clients"`
	}
	if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
		writeJSON(w, http.StatusBadRequest, inputSendModeAPIResponse{Error: "invalid JSON"})
		return
	}
	if body.Mode > uint32(pb.InputSendMode_INPUT_SEND_RELIABLE) {
		writeJSON(w, http.StatusBadRequest, inputSendModeAPIResponse{Error: "mode must be 0..3"})
		return
	}
	if !body.AllClients && body.ClientID == 0 {
		// Dashboard default: apply to every registered slave.
		body.AllClients = true
	}

	resp, err := link.InputSendMode(&pb.InputSendModeRequest{
		Write:      true,
		Mode:       pb.InputSendMode(body.Mode),
		ClientId:   body.ClientID,
		AllClients: body.AllClients,
	})
	if err != nil {
		writeJSON(w, http.StatusBadGateway, inputSendModeAPIResponse{Error: err.Error()})
		return
	}
	status := http.StatusOK
	if !resp.GetSuccess() {
		status = http.StatusBadRequest
	}
	writeJSON(w, status, inputSendModeAPIResponse{
		Success:       resp.GetSuccess(),
		Mode:          uint32(resp.GetMode()),
		ModeName:      inputSendModeName(resp.GetMode()),
		ClientID:      resp.GetClientId(),
		SlavesUpdated: resp.GetSlavesUpdated(),
	})
}