Switch Garmin messaging from IPC Inbound API to MapShare API

garmin.go

@@ -1,68 +1,61 @@
 package main
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
 	"io"
 	"log"
 	"net/http"
-	"time"
+	"net/url"
+	"strings"
 )
 
 type garminClient struct {
-	c      *http.Client
-	apiKey string
+	c          *http.Client
+	mapshareID string
 }
 
-type garminMessageRequest struct {
-	Messages []garminMessage `json:"messages"`
+type garminResponse struct {
+	Success bool `json:"success"`
+	Error   *struct {
+		Code int    `json:"code"`
+		Msg  string `json:"msg"`
+	} `json:"error"`
 }
 
-type garminMessage struct {
-	Recipients []string `json:"recipients"`
-	Sender     string   `json:"sender"`
-	Timestamp  string   `json:"timestamp"`
-	Message    string   `json:"message"`
-}
-
-type garminMessageResponse struct {
-	Count int `json:"count"`
-}
-
-func newGarminClient(apiKey string) *garminClient {
+func newGarminClient(mapshareID string) *garminClient {
 	return &garminClient{
-		c:      &http.Client{},
-		apiKey: apiKey,
+		c:          &http.Client{},
+		mapshareID: mapshareID,
 	}
 }
 
-func (gc *garminClient) sendMessage(imeis []string, sender, msg string) error {
-	buf := &bytes.Buffer{}
-	err := json.NewEncoder(buf).Encode(garminMessageRequest{
-		Messages: []garminMessage{
-			{
-				Recipients: imeis,
-				Sender:     sender,
-				Timestamp:  time.Now().UTC().Format("2006-01-02T15:04:05Z"),
-				Message:    msg,
-			},
-		},
-	})
+func (gc *garminClient) sendMessage(deviceIDs []string, sender, msg string) error {
+	for _, deviceID := range deviceIDs {
+		err := gc.sendToDevice(deviceID, sender, msg)
+		if err != nil {
+			return fmt.Errorf("device %s: %w", deviceID, err)
+		}
+	}
+	return nil
+}
 
+func (gc *garminClient) sendToDevice(deviceID, sender, msg string) error {
+	data := url.Values{}
+	data.Set("deviceIds", deviceID)
+	data.Set("messageText", msg)
+	data.Set("fromAddr", sender)
+
+	endpoint := fmt.Sprintf("https://share.garmin.com/%s/Map/SendMessageToDevices", gc.mapshareID)
+
+	log.Printf("[->garmin] %s %s", endpoint, data.Encode())
+
+	req, err := http.NewRequest("POST", endpoint, strings.NewReader(data.Encode()))
 	if err != nil {
 		return err
 	}
 
-	log.Printf("[->garmin] %s", buf.String())
-
-	req, err := http.NewRequest("POST", "https://ipcinbound.inreachapp.com/IPC/IPCInboundApi/api/Messaging/Message", buf)
-	if err != nil {
-		return err
-	}
-
-	req.Header.Set("Content-Type", "application/json")
-	req.Header.Set("x-api-key", gc.apiKey)
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
 
 	resp, err := gc.c.Do(req)
 	if err != nil {
@@ -72,20 +65,23 @@ func (gc *garminClient) sendMessage(imeis []string, sender, msg string) error {
 	defer resp.Body.Close()
 	body, _ := io.ReadAll(resp.Body)
 
+	log.Printf("[<-garmin] %d %s", resp.StatusCode, string(body))
+
 	if resp.StatusCode != 200 {
-		return fmt.Errorf("%s", string(body))
+		return fmt.Errorf("HTTP %d: %s", resp.StatusCode, string(body))
 	}
 
-	grResp := garminMessageResponse{}
+	var grResp garminResponse
 	err = json.Unmarshal(body, &grResp)
 	if err != nil {
-		return err
+		return fmt.Errorf("parse response: %w", err)
 	}
 
-	log.Printf("[<-garmin] %s", string(body))
-
-	if grResp.Count != len(imeis) {
-		return fmt.Errorf("expected %d messages, got %d", len(imeis), grResp.Count)
+	if !grResp.Success {
+		if grResp.Error != nil {
+			return fmt.Errorf("garmin error %d: %s", grResp.Error.Code, grResp.Error.Msg)
+		}
+		return fmt.Errorf("garmin returned success=false")
 	}
 
 	return nil