BangleApps/modules/Settings.js

102 lines
3.3 KiB
JavaScript

/*
- Read/write app settings, stored in <appid>.json
- Read/write global settings (stored in setting.json)
Usage:
```
// read a single app setting
value = require('Settings').get(appid, key, default);
// omit key to read all app settings
value = require('Settings').get(appid);
// write a single app setting
require('Settings').set(appid, key, value)
// omit key and pass an object as values to overwrite all settings
require('Settings').set(appid, values)
// read Bangle settings by passing the Bangle object instead of an app name
value = require('Settings').get(Bangle, key, default);
// read all global settings
values = require('Settings').get(Bangle);
// write a global setting
require('Settings').set(Bangle, key, value)
```
For example:
```
require('Settings').set('test', 'foo', 123); // writes to 'test.json'
require('Settings').set('test', 'bar', 456); // updates 'test.json'
// 'test.json' now contains {baz:123,bam:456}
baz = require('Settings').get('test', 'foo'); // baz = 123
def = require('Settings').get('test', 'jkl', 789); // def = 789
all = require('Settings').get('test'); // all = {foo: 123, bar: 456}
baz = require('Settings').get('test', 'baz'); // baz = undefined
// read global setting
vibrate = require('Settings').get(Bangle, 'vibrate', true);
// Hint: if your app reads multiple settings, you can create a helper function:
function s(key, def) { return require('Settings').get('myapp', key, def); }
var foo = s('foo setting', 'default value'), bar = s('bar setting');
```
*/
/**
* Read setting value from file
*
* @param {string} file Settings file
* @param {string} key Setting to get, omit to get all settings as object
* @param {*} def Default value
* @return {*} Setting value (or default if not found)
*/
function get(file, key, def) {
var s = require("Storage").readJSON(file);
if (def===undefined && ["object", "undefined"].includes(typeof key)) {
// get(file) or get(file, def): get all settings
return (s!==undefined) ? s : key;
}
return ((typeof s==="object") && (key in s)) ? s[key] : def;
}
/**
* Write setting value to file
*
* @param {string} file Settings file
* @param {string} key Setting to change, omit to replace all settings
* @param {*} value Value to store
*/
function set(file, key, value) {
if (value===undefined && typeof key==="object") {
// set(file, value): overwrite settings completely
require("Storage").writeJSON(file, key);
return;
}
var s = require("Storage").readJSON(file, 1);
if (typeof s!=="object") s = {};
s[key] = value;
require("Storage").write(file, s);
}
/**
* Read setting value
*
* @param {string|object} app App name or Bangle
* @param {string} key Setting to get, omit to get all settings as object
* @param {*} def Default value
* @return {*} Setting value (or default if not found)
*/
exports.get = function(app, key, def) {
return get((app===Bangle) ? 'setting.json' : app+".json", key, def);
};
/**
* Write setting value
*
* @param {string|object} app App name or Bangle
* @param {string} key Setting to change, omit to replace all settings
* @param {*} val Value to store
*/
exports.set = function(app, key, val) {
set((app===Bangle) ? 'setting.json' : app+".json", key, val);
};