webamp/js/utils.js
2017-10-12 15:18:25 -07:00

112 lines
3.3 KiB
JavaScript

export const getTimeObj = time => {
const minutes = Math.floor(time / 60);
const seconds = time % 60;
return {
minutesFirstDigit: Math.floor(minutes / 10),
minutesSecondDigit: Math.floor(minutes % 10),
secondsFirstDigit: Math.floor(seconds / 10),
secondsSecondDigit: Math.floor(seconds % 10)
};
};
export const getTimeStr = time => {
const timeObj = getTimeObj(time);
return [
timeObj.minutesFirstDigit,
timeObj.minutesSecondDigit,
":",
timeObj.secondsFirstDigit,
timeObj.secondsSecondDigit
].join("");
};
export const parseViscolors = text => {
const entries = text.split("\n");
const regex = /^(\d+)\s*,\s*(\d+)\s*,\s*(\d+)/;
const colors = [];
// changed to a hard number to deal with empty lines at the end...
// plus it's only meant to be an exact quantity of numbers anyway.
// - @PAEz
for (let i = 0; i < 24; i++) {
const matches = regex.exec(entries[i]);
if (matches) {
colors[i] = `rgb(${matches.slice(1, 4).join(",")})`;
} else {
console.error(`Error in VISCOLOR.TXT on line ${i}`);
}
}
return colors;
};
// Dumb ini parser that just gets all the key/value pairs
export const parseIni = text => {
const lines = text.split(/[\r\n]+/g);
return lines.reduce((data, line) => {
if (line.includes("=")) {
const [key, value] = line.split("=");
data[key] = value;
}
return data;
}, {});
};
export const clamp = (value, min, max) => Math.min(Math.max(value, min), max);
export const base64FromArrayBuffer = arrayBuffer => {
const dataView = new Uint8Array(arrayBuffer);
return window.btoa(String.fromCharCode(...dataView));
};
// https://stackoverflow.com/a/15832662/1263117
export function downloadURI(uri, name) {
const link = document.createElement("a");
link.download = name;
link.href = uri;
window.document.body.appendChild(link);
link.click();
window.document.body.removeChild(link);
}
export const toPercent = (min, max, value) => (value - min) / (max - min);
export const percentToRange = (percent, min, max) =>
min + Math.round(percent * (max - min));
export const percentToIndex = (percent, length) =>
percentToRange(percent, 0, length - 1);
const rebound = (oldMin, oldMax, newMin, newMax) => oldValue =>
percentToRange(toPercent(oldMin, oldMax, oldValue), newMin, newMax);
// Convert a .eqf value to a 1-100
export const normalize = rebound(1, 64, 1, 100);
// Convert a 0-100 to an .eqf value
export const denormalize = rebound(1, 100, 1, 64);
// Merge a `source` object to a `target` recursively
export const merge = (target, source) => {
// Iterate through `source` properties and if an `Object` set property to merge of `target` and `source` properties
for (const key of Object.keys(source)) {
if (source[key] instanceof Object)
Object.assign(source[key], merge(target[key], source[key]));
}
// Join `target` and modified `source`
Object.assign(target || {}, source);
return target;
};
// Maps a value in a range (defined my min/max) to a value in an array (options).
export const segment = (min, max, value, newValues) => {
const ratio = toPercent(min, max, value);
/*
| 0 | 1 | 2 |
0 1 2 3
*/
return newValues[percentToIndex(ratio, newValues.length)];
};
export const arraysAreEqual = (a, b) =>
a.length === b.length && a.every((value, i) => value === b[i]);