From 9a6d2acc314908b1c6e9b9daceed2bb29d464f68 Mon Sep 17 00:00:00 2001
From: Luxferre <lux@ferre>
Date: Fri, 23 Dec 2022 17:02:10 +0200
Subject: [PATCH] Added setSyncDelta method to the library

---
 README.md       | 3 ++-
 manifest.webapp | 2 +-
 rcvd.js         | 7 ++++---
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 8ae2177..7128567 100644
--- a/README.md
+++ b/README.md
@@ -40,7 +40,8 @@ The [library](rcvd.js) can be used "as is" or as a building block for more advan
 - `RCVD.connect() -> Promise` - connect to a watch, perform the necessary handshake operations and resolve the Promise on success;
 - `RCVD.disconnect()` - disconnect from the currently connected watch's GATT server;
 - `RCVD.sync(Date obj?) -> Promise` - perform time synchronization with the **optional** Date object (if it's not passed, actual current local time will be set), running all the required DST/world time setting cycles before setting the actual time;
-- `RCVD.getModel() -> String` - return the watch model name obdained during the connection process;
+- `RCVD.setSyncDelta(ms)` - update the delta value (in milliseconds) to add to the current time before synchronization to make up for the Bluetooth transmission delay (500 ms by default, can be adjusted according to your host and watch latency);
+- `RCVD.getModel() -> String` - return the watch model name obtained during the connection process;
 - `RCVD.rawRead(uint8 param1, uint8 param2...) -> Promise(Uint8Array)` - accept variable number of integer parameters and execute the read command on the watch, resolving to the result in a Uint8Array value;
 - `RCVD.rawWrite(Uint8Array command) -> Promise` - accept a write command shaped as byte data in Uint8Array and resolve on successful write operation.
 
diff --git a/manifest.webapp b/manifest.webapp
index 20e6bc4..5cd97d5 100644
--- a/manifest.webapp
+++ b/manifest.webapp
@@ -1,5 +1,5 @@
 {
-  "version": "0.0.3",
+  "version": "0.0.4",
   "name": "RCVD",
   "description": "Casio BLE-enabled watches time synchronization app",
   "type": "certified",
diff --git a/rcvd.js b/rcvd.js
index 62745a5..fb95fe9 100644
--- a/rcvd.js
+++ b/rcvd.js
@@ -16,6 +16,7 @@ RCVD = (function(nav) {
     }),
     watchModel = '',
     localgatt = null, //local GATT reference for disconnection
+    syncDelta = 500, //the delta value (in milliseconds) to make up for BLE transmission latency, 500 ms by default
     TD = new TextDecoder(),
     ids = s => `26eb00${s}-b012-49a8-b1f8-394fb2032b0f`,
     scanids = ['00001804-0000-1000-8000-00805f9b34fb', ids('0d')],
@@ -83,7 +84,7 @@ RCVD = (function(nav) {
 
     plgen = k => [...Array(6)].map((a,i)=>[k,i]), //property list generator
     cyclePresyncProperties = _ => new Promise((res, rej) => {
-      var slist = [...plgen(30),...plgen(31)]
+      var slist = [...plgen(30),...plgen(31)] //full property list for primary targets, GW-B/GMW-B models
       if(watchModel.indexOf('OCW') > 5)
         slist = [[30,0],[30,1]]
       else if(watchModel.indexOf('B2100') > 5 || watchModel.indexOf('B001') > 5 || watchModel.indexOf('DW-B5600') > 5 )
@@ -122,10 +123,10 @@ RCVD = (function(nav) {
     getModel: _ => watchModel,
     rawRead: execReadCmd,
     rawWrite: execWriteCmd,
+    setSyncDelta: val => {syncDelta = +val; if(isNaN(syncDelta)) syncDelta = 500},
     sync: dObj => new Promise((res, rej) => {
       cyclePresyncProperties().then(_ => {
-        //set to the next second to make up for latency
-        var d = dObj || new Date(Date.now() + 500), year = d.getFullYear()
+        var d = dObj || new Date(Date.now() + syncDelta), year = d.getFullYear()
         execWriteCmd(Uint8Array.from([
           9,
           year&255, year>>>8,