From b25d1eaf86b839d1ac1d72aaa0ea685b1a088689 Mon Sep 17 00:00:00 2001
From: Jake Archibald <jaffathecake@gmail.com>
Date: Tue, 2 Oct 2018 11:41:07 +0100
Subject: [PATCH] <range-input> (#171)

---
 src/codecs/generic/quality-option.tsx         |   4 +-
 src/codecs/imagequant/options.tsx             |   6 +-
 src/codecs/webp/options.tsx                   |  46 +++----
 src/codecs/webp/styles.scss                   |   3 -
 .../Output/custom-els/RangeInput/index.ts     | 115 ++++++++++++++++++
 .../custom-els/RangeInput/missing-types.d.ts  |   5 +
 .../Output/custom-els/RangeInput/styles.css   | 109 +++++++++++++++++
 7 files changed, 249 insertions(+), 39 deletions(-)
 create mode 100644 src/components/Output/custom-els/RangeInput/index.ts
 create mode 100644 src/components/Output/custom-els/RangeInput/missing-types.d.ts
 create mode 100644 src/components/Output/custom-els/RangeInput/styles.css

diff --git a/src/codecs/generic/quality-option.tsx b/src/codecs/generic/quality-option.tsx
index 2053019f..85ea508c 100644
--- a/src/codecs/generic/quality-option.tsx
+++ b/src/codecs/generic/quality-option.tsx
@@ -1,5 +1,6 @@
 import { h, Component } from 'preact';
 import { bind } from '../../lib/util';
+import '../../components/output/custom-els/RangeInput';
 
 interface EncodeOptions {
   quality: number;
@@ -35,9 +36,8 @@ export default function qualityOption(opts: QualityOptionArg = {}) {
         <div>
           <label>
             Quality:
-            <input
+            <range-input
               name="quality"
-              type="range"
               min={min}
               max={max}
               step={step || 'any'}
diff --git a/src/codecs/imagequant/options.tsx b/src/codecs/imagequant/options.tsx
index a20a3084..0cb841dc 100644
--- a/src/codecs/imagequant/options.tsx
+++ b/src/codecs/imagequant/options.tsx
@@ -50,9 +50,8 @@ export default class QuantizerOptions extends Component<Props, State> {
         </label>
         <label style={{ display: options.zx ? 'none' : '' }}>
           Palette Colors:
-          <input
+          <range-input
             name="maxNumColors"
-            type="range"
             min="2"
             max="256"
             value={'' + options.maxNumColors}
@@ -61,9 +60,8 @@ export default class QuantizerOptions extends Component<Props, State> {
         </label>
         <label>
           Dithering:
-          <input
+          <range-input
             name="dither"
-            type="range"
             min="0"
             max="1"
             step="0.01"
diff --git a/src/codecs/webp/options.tsx b/src/codecs/webp/options.tsx
index f18125fd..fbed0d90 100644
--- a/src/codecs/webp/options.tsx
+++ b/src/codecs/webp/options.tsx
@@ -55,12 +55,12 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
       filter_type: inputFieldCheckedAsNumber(form.filter_type),
       use_sharp_yuv: inputFieldCheckedAsNumber(form.use_sharp_yuv),
       // .value
-      near_lossless: inputFieldValueAsNumber(form.near_lossless),
+      near_lossless: 100 - inputFieldValueAsNumber(form.near_lossless),
       alpha_quality: inputFieldValueAsNumber(form.alpha_quality),
       alpha_filtering: inputFieldValueAsNumber(form.alpha_filtering),
       sns_strength: inputFieldValueAsNumber(form.sns_strength),
       filter_strength: inputFieldValueAsNumber(form.filter_strength),
-      filter_sharpness: inputFieldValueAsNumber(form.filter_sharpness),
+      filter_sharpness: 7 - inputFieldValueAsNumber(form.filter_sharpness),
       pass: inputFieldValueAsNumber(form.pass),
       preprocessing: inputFieldValueAsNumber(form.preprocessing),
       segments: inputFieldValueAsNumber(form.segments),
@@ -74,9 +74,8 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
       <div>
         <label>
           Effort:
-          <input
+          <range-input
             name="lossless_preset"
-            type="range"
             min="0"
             max="9"
             value={'' + determineLosslessQuality(options.quality)}
@@ -85,13 +84,11 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
         </label>
         <label>
           Slight loss:
-          <input
-            class={styles.flipRange}
+          <range-input
             name="near_lossless"
-            type="range"
             min="0"
             max="100"
-            value={'' + options.near_lossless}
+            value={'' + (100 - options.near_lossless)}
             onChange={this.onChange}
           />
         </label>
@@ -119,9 +116,8 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
       <div>
         <label>
           Effort:
-          <input
+          <range-input
             name="method_input"
-            type="range"
             min="0"
             max="6"
             value={'' + options.method}
@@ -130,9 +126,8 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
         </label>
         <label>
           Quality:
-          <input
+          <range-input
             name="quality"
-            type="range"
             min="0"
             max="100"
             step="0.01"
@@ -151,9 +146,8 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
         </label>
         <label>
           Alpha quality:
-          <input
+          <range-input
             name="alpha_quality"
-            type="range"
             min="0"
             max="100"
             value={'' + options.alpha_quality}
@@ -162,9 +156,8 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
         </label>
         <label>
           Alpha filter quality:
-          <input
+          <range-input
             name="alpha_filtering"
-            type="range"
             min="0"
             max="2"
             value={'' + options.alpha_filtering}
@@ -173,9 +166,8 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
         </label>
         <label>
           Spacial noise shaping:
-          <input
+          <range-input
             name="sns_strength"
-            type="range"
             min="0"
             max="100"
             value={'' + options.sns_strength}
@@ -193,9 +185,8 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
         </label>
         <label>
           Filter strength:
-          <input
+          <range-input
             name="filter_strength"
-            type="range"
             min="0"
             max="100"
             disabled={!!options.autofilter}
@@ -214,13 +205,11 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
         </label>
         <label>
           Filter sharpness:
-          <input
-            class={styles.flipRange}
+          <range-input
             name="filter_sharpness"
-            type="range"
             min="0"
             max="7"
-            value={'' + options.filter_sharpness}
+            value={'' + (7 - options.filter_sharpness)}
             onChange={this.onChange}
           />
         </label>
@@ -235,9 +224,8 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
         </label>
         <label>
           Passes:
-          <input
+          <range-input
             name="pass"
-            type="range"
             min="1"
             max="10"
             value={'' + options.pass}
@@ -258,9 +246,8 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
         </label>
         <label>
           Segments:
-          <input
+          <range-input
             name="segments"
-            type="range"
             min="1"
             max="4"
             value={'' + options.segments}
@@ -269,9 +256,8 @@ export default class WebPEncoderOptions extends Component<Props, {}> {
         </label>
         <label>
           Partitions:
-          <input
+          <range-input
             name="partitions"
-            type="range"
             min="0"
             max="3"
             value={'' + options.partitions}
diff --git a/src/codecs/webp/styles.scss b/src/codecs/webp/styles.scss
index cffbc045..aaa3d95c 100644
--- a/src/codecs/webp/styles.scss
+++ b/src/codecs/webp/styles.scss
@@ -1,6 +1,3 @@
-.flip-range {
-  transform: scaleX(-1);
-}
 .hide {
   display: none;
 }
diff --git a/src/components/Output/custom-els/RangeInput/index.ts b/src/components/Output/custom-els/RangeInput/index.ts
new file mode 100644
index 00000000..bf5f522a
--- /dev/null
+++ b/src/components/Output/custom-els/RangeInput/index.ts
@@ -0,0 +1,115 @@
+import { bind } from '../../../../lib/util';
+import './styles.css';
+
+const RETARGETED_EVENTS = ['focus', 'blur'];
+const UPDATE_EVENTS = ['input', 'change'];
+const REFLECTED_PROPERTIES = ['name', 'min', 'max', 'step', 'value', 'disabled'];
+const REFLECTED_ATTRIBUTES = ['name', 'min', 'max', 'step', 'value', 'disabled'];
+
+class RangeInputElement extends HTMLElement {
+  private _input = document.createElement('input');
+  private _valueDisplayWrapper = document.createElement('div');
+  private _valueDisplay = document.createElement('span');
+  private _ignoreChange = false;
+
+  static get observedAttributes() {
+    return REFLECTED_ATTRIBUTES;
+  }
+
+  constructor() {
+    super();
+    this._input.type = 'range';
+
+    for (const event of RETARGETED_EVENTS) {
+      this._input.addEventListener(event, this._retargetEvent, true);
+    }
+
+    for (const event of UPDATE_EVENTS) {
+      this._input.addEventListener(event, this._update, true);
+    }
+  }
+
+  get labelPrecision(): string {
+    return this.getAttribute('label-precision') || '';
+  }
+
+  set labelPrecision(precision: string) {
+    this.setAttribute('label-precision', precision);
+  }
+
+  connectedCallback() {
+    if (this._input.parentNode !== this) {
+      this.appendChild(this._input);
+      this._valueDisplayWrapper.appendChild(this._valueDisplay);
+      this.appendChild(this._valueDisplayWrapper);
+    }
+  }
+
+  attributeChangedCallback(name: string, oldValue: string, newValue: string | null) {
+    if (this._ignoreChange) return;
+    if (newValue === null) {
+      this._input.removeAttribute(name);
+    } else {
+      this._input.setAttribute(name, newValue);
+    }
+    this._reflectAttributes();
+    this._update();
+  }
+
+  @bind
+  private _retargetEvent(event: Event) {
+    event.stopImmediatePropagation();
+    const retargetted = new Event(event.type, event);
+    this.dispatchEvent(retargetted);
+  }
+
+  @bind
+  private _update() {
+    const value = parseFloat(this.value || '0');
+    const min = parseFloat(this.min || '0');
+    const max = parseFloat(this.max || '100');
+    const labelPrecision = parseFloat(this.labelPrecision || '0');
+    const percent = 100 * (value - min) / (max - min);
+    const displayValue = labelPrecision ? value.toPrecision(labelPrecision) :
+      Math.round(value).toString();
+
+    this.style.setProperty('--value-percent', percent + '%');
+    this._valueDisplay.textContent = displayValue;
+  }
+
+  private _reflectAttributes() {
+    this._ignoreChange = true;
+    for (const attributeName in REFLECTED_ATTRIBUTES) {
+      const attributeValue = this._input.getAttribute(attributeName);
+      if (attributeValue === null) continue;
+      this.setAttribute(attributeName, attributeValue);
+    }
+    this._ignoreChange = false;
+  }
+}
+
+interface RangeInputElement {
+  name: string;
+  min: string;
+  max: string;
+  step: string;
+  value: string;
+  disabled: boolean;
+}
+
+for (const prop of REFLECTED_PROPERTIES) {
+  Object.defineProperty(RangeInputElement.prototype, prop, {
+    get() {
+      return this._input[prop];
+    },
+    set(val) {
+      this._input[prop] = val;
+      this._reflectAttributes();
+      this._update();
+    },
+  });
+}
+
+export default RangeInputElement;
+
+customElements.define('range-input', RangeInputElement);
diff --git a/src/components/Output/custom-els/RangeInput/missing-types.d.ts b/src/components/Output/custom-els/RangeInput/missing-types.d.ts
new file mode 100644
index 00000000..d566207d
--- /dev/null
+++ b/src/components/Output/custom-els/RangeInput/missing-types.d.ts
@@ -0,0 +1,5 @@
+declare namespace JSX {
+  interface IntrinsicElements {
+    'range-input': HTMLAttributes;
+  }
+}
diff --git a/src/components/Output/custom-els/RangeInput/styles.css b/src/components/Output/custom-els/RangeInput/styles.css
new file mode 100644
index 00000000..d3512704
--- /dev/null
+++ b/src/components/Output/custom-els/RangeInput/styles.css
@@ -0,0 +1,109 @@
+range-input {
+  position: relative;
+  display: flex;
+  height: 18px;
+  width: 130px;
+  margin: 2px;
+  font: inherit;
+  line-height: 16px;
+  overflow: visible;
+}
+
+range-input input {
+  position: relative;
+  flex: 1;
+  width: 100%;
+  padding: 0 !important;
+  margin: 0 !important;
+  background: none;
+  appearance: none;
+  -webkit-appearance: none;
+  outline: none;
+}
+
+range-input input::-webkit-slider-runnable-track,
+range-input input::-moz-range-track,
+range-input input::-ms-track {
+  appearance: none;
+  -ms-appearance: none;
+  -moz-appearance: none;
+  -webkit-appearance: none;
+}
+
+range-input::before {
+  content: '';
+  display: block;
+  position: absolute;
+  top: 8px;
+  left: 0;
+  width: 100%;
+  height: 2px;
+  outline: none;
+  border: none;
+  background: #eee;
+  border-radius: 1px;
+  box-shadow: 0 -.5px 0 rgba(0,0,0,0.3), inset 0 .5px 0 rgba(255,255,255,0.2), 0 .5px 0 rgba(255,255,255,0.3);
+  background: linear-gradient(#34B9EB, #218ab1) 0/ var(--value-percent, 0%) 100% no-repeat #eee;
+}
+range-input[disabled]::before {
+  background: linear-gradient(#aaa, #888) 0/ var(--value-percent, 0%) 100% no-repeat #eee;
+}
+
+range-input input::-webkit-slider-thumb {
+  appearance: none;
+  -webkit-appearance: none;
+  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" width="10" height="10"><circle cx="5" cy="5" r="1" fill="#5D509E" /></svg>') center no-repeat #34B9EB;
+  box-sizing: content-box;
+  border-radius: 50%;
+  width: 12px;
+  height: 12px;
+  border: none;
+  box-shadow: 0 0.5px 2px rgba(0,0,0,0.3);
+  outline: none;
+}
+
+range-input[disabled] input::-webkit-slider-thumb {
+  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" width="10" height="10"><circle cx="5" cy="5" r="1" fill="#666" /></svg>') center no-repeat #999;
+}
+
+range-input input:focus::-webkit-slider-thumb {
+  box-shadow: 0 1px 3px rgba(0,0,0,0.5);
+}
+
+range-input > div {
+  position: absolute;
+  left: 6px;
+  right: 6px;
+  bottom: 0;
+  height: 0;
+  overflow: visible;
+}
+
+range-input > div > span {
+  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" width="32" height="62" fill="none"><path fill="#34B9EB" d="M27.3 27.3C25 29.6 17 35.8 17 43v3c0 3 2.5 5 3.2 5.8a6 6 0 1 1-8.5 0C12.6 51 15 49 15 46v-3c0-7.2-8-13.4-10.3-15.7A16 16 0 0 1 16 0a16 16 0 0 1 11.3 27.3z"/><circle cx="16" cy="56" r="1" fill="#5D509E"/></svg>') top center no-repeat;
+  position: absolute;
+  box-sizing: border-box;
+  left: var(--value-percent, 0%);
+  bottom: 3px;
+  width: 32px;
+  height: 62px;
+  text-align: center;
+  padding: 8px 3px 0;
+  margin: 0 0 0 -16px;
+  filter: drop-shadow(0 1px 3px rgba(0,0,0,0.3));
+  transform-origin: 50% 90%;
+  opacity: 0.0001;
+  transform: scale(.2);
+  color: #fff;
+  font: inherit;
+  text-overflow: clip;
+  text-shadow: 0 -.5px 0 rgba(0,0,0,0.4);
+  transition: transform 200ms ease, opacity 200ms ease;
+  will-change: transform;
+  pointer-events: none;
+  overflow: hidden;
+}
+range-input input:focus + div span {
+  opacity: 1;
+  transform: scale(1);
+}