From 43223a02eecd68642404b09c3085f435722cb144 Mon Sep 17 00:00:00 2001
From: Florian Forster <ff@octo.it>
Date: Thu, 11 Jan 2018 21:45:43 +0100
Subject: [PATCH] Write step count summary to Google Fit.

---
 gfit/gfit.go | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 gfitsync.go  | 18 +++++++++++++----
 2 files changed, 80 insertions(+), 4 deletions(-)

diff --git a/gfit/gfit.go b/gfit/gfit.go
index 028eee0..ed8f7cb 100644
--- a/gfit/gfit.go
+++ b/gfit/gfit.go
@@ -4,11 +4,14 @@ import (
 	"context"
 	"fmt"
 	"net/http"
+	"time"
 
 	"github.com/octo/gfitsync/app"
 	"golang.org/x/oauth2"
 	oauth2google "golang.org/x/oauth2/google"
 	fitness "google.golang.org/api/fitness/v1"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/log"
 )
 
 var oauthConfig = &oauth2.Config{
@@ -24,6 +27,14 @@ var oauthConfig = &oauth2.Config{
 
 const csrfToken = "@CSRFTOKEN@"
 
+func Application(ctx context.Context) *fitness.Application {
+	return &fitness.Application{
+		Name:       "Fitbit to Google Fit sync",
+		Version:    appengine.VersionID(ctx),
+		DetailsUrl: "", // optional
+	}
+}
+
 func AuthURL() string {
 	return oauthConfig.AuthCodeURL(csrfToken, oauth2.AccessTypeOffline)
 }
@@ -60,3 +71,58 @@ func NewClient(ctx context.Context, u *app.User) (*Client, error) {
 		Service: service,
 	}, nil
 }
+
+func (c *Client) SetSteps(ctx context.Context, steps int, date time.Time) error {
+	const userID = "me"
+	const dataTypeName = "com.google.step_count.delta"
+	dataSource := &fitness.DataSource{
+		Application:    Application(ctx),
+		DataStreamName: "", // "daily summary"?
+		DataType: &fitness.DataType{
+			Field: []*fitness.DataTypeField{
+				&fitness.DataTypeField{
+					Format: "integer",
+					Name:   "steps",
+				},
+			},
+			Name: dataTypeName,
+		},
+		Name: "Step Count",
+		Type: "raw",
+	}
+
+	dataSource, err := c.Service.Users.DataSources.Create(userID, dataSource).Context(ctx).Do()
+	if err != nil {
+		log.Errorf(ctx, "c.Service.Users.DataSources.Create() = (%+v, %v)", dataSource, err)
+		return err
+	}
+	dataSourceID := dataSource.DataStreamId
+
+	startTimeNanos := date.UnixNano()
+	endTimeNanos := date.Add(86399999999999 * time.Nanosecond).UnixNano()
+	datasetID := fmt.Sprintf("%d-%d", startTimeNanos, endTimeNanos)
+	dataset := &fitness.Dataset{
+		MinStartTimeNs: startTimeNanos,
+		MaxEndTimeNs:   endTimeNanos,
+		Point: []*fitness.DataPoint{
+			&fitness.DataPoint{
+				ComputationTimeMillis: time.Now().UnixNano() / 1000000,
+				DataTypeName:          dataTypeName,
+				StartTimeNanos:        startTimeNanos,
+				EndTimeNanos:          endTimeNanos,
+				Value: []*fitness.Value{
+					&fitness.Value{
+						IntVal: int64(steps),
+					},
+				},
+			},
+		},
+	}
+
+	dataset, err = c.Service.Users.DataSources.Datasets.Patch(userID, dataSourceID, datasetID, dataset).Context(ctx).Do()
+	if err != nil {
+		log.Errorf(ctx, "c.Service.Users.DataSources.Datasets.Patch() = (%+v, %v)", dataset, err)
+		return err
+	}
+	return nil
+}
diff --git a/gfitsync.go b/gfitsync.go
index 2bc3b73..22f4c56 100644
--- a/gfitsync.go
+++ b/gfitsync.go
@@ -218,21 +218,31 @@ func handleNotification(ctx context.Context, s *fitbit.Subscription) error {
 	if err != nil {
 		return err
 	}
-	c, err := fitbit.NewClient(ctx, s.OwnerID, u)
+
+	tm, err := time.Parse("2006-01-02", s.Date)
 	if err != nil {
 		return err
 	}
 
-	tm, err := time.Parse("2006-01-02", s.Date)
+	fitbitClient, err := fitbit.NewClient(ctx, s.OwnerID, u)
 	if err != nil {
 		return err
 	}
 
-	summary, err := c.ActivitySummary(tm)
+	summary, err := fitbitClient.ActivitySummary(tm)
 	if err != nil {
 		return err
 	}
-
 	log.Debugf(ctx, "ActivitySummary for %s = %+v", u.Email, summary)
+
+	gfitClient, err := gfit.NewClient(ctx, u)
+	if err != nil {
+		return err
+	}
+
+	if err := gfitClient.SetSteps(ctx, summary.Summary.Steps, tm); err != nil {
+		return fmt.Errorf("gfitClient.SetSteps(%d) = %v", summary.Summary.Steps, err)
+	}
+
 	return nil
 }
-- 
2.11.0