Tidy of components

- Moved all components into a single directory like nextjs
 - Made component names consistent with each other
 - Made component names consistent with their export class names
 - Added storybook for a few components with the aim to extend this further.

src/components/_ZoomProperty.jsx

@@ -0,0 +1,194 @@
+import React from 'react'
+import PropTypes from 'prop-types'
+import {mdiFunctionVariant, mdiTableRowPlusAfter} from '@mdi/js';
+
+import Button from './Button'
+import SpecField from './SpecField'
+import FieldNumber from './FieldNumber'
+import Block from './Block'
+
+import DeleteStopButton from './_DeleteStopButton'
+import labelFromFieldName from './_labelFromFieldName'
+
+import docUid from '../libs/document-uid'
+import sortNumerically from '../libs/sort-numerically'
+
+
+/**
+ * We cache a reference for each stop by its index.
+ *
+ * When the stops are reordered the references are also updated (see this.orderStops) this allows React to use the same key for the element and keep keyboard focus.
+ */
+function setStopRefs(props, state) {
+  // This is initialsed below only if required to improved performance.
+  let newRefs;
+
+  if(props.value && props.value.stops) {
+    props.value.stops.forEach((val, idx) => {
+      if(!state.refs.hasOwnProperty(idx)) {
+        if(!newRefs) {
+          newRefs = {...state};
+        }
+        newRefs[idx] = docUid("stop-");
+      }
+    })
+  }
+
+  return newRefs;
+}
+
+
+export default class ZoomProperty extends React.Component {
+  static propTypes = {
+    onChange: PropTypes.func,
+    onDeleteStop: PropTypes.func,
+    onAddStop: PropTypes.func,
+    onExpressionClick: PropTypes.func,
+    fieldType: PropTypes.string,
+    fieldName: PropTypes.string,
+    fieldSpec: PropTypes.object,
+    errors: PropTypes.object,
+    value: PropTypes.oneOfType([
+      PropTypes.object,
+      PropTypes.string,
+      PropTypes.number,
+      PropTypes.bool,
+      PropTypes.array
+    ]),
+  }
+
+  static defaultProps = {
+    errors: {},
+  }
+
+  state = {
+    refs: {}
+  }
+
+  componentDidMount() {
+    const newRefs = setStopRefs(this.props, this.state);
+
+    if(newRefs) {
+      this.setState({
+        refs: newRefs
+      })
+    }
+  }
+
+  static getDerivedStateFromProps(props, state) {
+    const newRefs = setStopRefs(props, state);
+    if(newRefs) {
+      return {
+        refs: newRefs
+      };
+    }
+    return null;
+  }
+
+  // Order the stops altering the refs to reflect their new position.
+  orderStopsByZoom(stops) {
+    const mappedWithRef = stops
+      .map((stop, idx) => {
+        return {
+          ref: this.state.refs[idx],
+          data: stop
+        }
+      })
+    // Sort by zoom
+      .sort((a, b) => sortNumerically(a.data[0], b.data[0]));
+
+    // Fetch the new position of the stops
+    const newRefs = {};
+    mappedWithRef
+      .forEach((stop, idx) =>{
+        newRefs[idx] = stop.ref;
+      })
+
+    this.setState({
+      refs: newRefs
+    });
+
+    return mappedWithRef.map((item) => item.data);
+  }
+
+  changeZoomStop(changeIdx, stopData, value) {
+    const stops = this.props.value.stops.slice(0);
+    stops[changeIdx] = [stopData, value];
+
+    const orderedStops = this.orderStopsByZoom(stops);
+
+    const changedValue = {
+      ...this.props.value,
+      stops: orderedStops
+    }
+    this.props.onChange(this.props.fieldName, changedValue)
+  }
+
+  render() {
+    const {fieldName, fieldType, errors} = this.props;
+
+    const zoomFields = this.props.value.stops.map((stop, idx) => {
+      const zoomLevel = stop[0]
+      const key  = this.state.refs[idx];
+      const value = stop[1]
+      const deleteStopBtn= <DeleteStopButton onClick={this.props.onDeleteStop.bind(this, idx)} />
+
+      const errorKeyStart = `${fieldType}.${fieldName}.stops[${idx}]`;
+      const foundErrors = Object.entries(errors).filter(([key, error]) => {
+        return key.startsWith(errorKeyStart);
+      });
+
+      const message = foundErrors.map(([key, error]) => {
+        return error.message;
+      }).join("");
+      const error = message ? {message} : undefined;
+
+      return <Block
+        error={error}
+        key={key}
+        fieldSpec={this.props.fieldSpec}
+        label={labelFromFieldName(this.props.fieldName)}
+        action={deleteStopBtn}
+      >
+        <div>
+          <div className="maputnik-zoom-spec-property-stop-edit">
+            <FieldNumber
+              value={zoomLevel}
+              onChange={changedStop => this.changeZoomStop(idx, changedStop, value)}
+              min={0}
+              max={22}
+            />
+          </div>
+          <div className="maputnik-zoom-spec-property-stop-value">
+            <SpecField
+              fieldName={this.props.fieldName}
+              fieldSpec={this.props.fieldSpec}
+              value={value}
+              onChange={(_, newValue) => this.changeZoomStop(idx, zoomLevel, newValue)}
+            />
+          </div>
+        </div>
+      </Block>
+    });
+
+    return <div className="maputnik-zoom-spec-property">
+      {zoomFields}
+      <Button
+        className="maputnik-add-stop"
+        onClick={this.props.onAddStop.bind(this)}
+      >
+        <svg style={{width:"14px", height:"14px", verticalAlign: "text-bottom"}} viewBox="0 0 24 24">
+          <path fill="currentColor" d={mdiTableRowPlusAfter} />
+        </svg> Add stop
+      </Button>
+      <Button
+        className="maputnik-add-stop"
+        onClick={this.props.onExpressionClick.bind(this)}
+      >
+        <svg style={{width:"14px", height:"14px", verticalAlign: "text-bottom"}} viewBox="0 0 24 24">
+          <path fill="currentColor" d={mdiFunctionVariant} />
+        </svg> Convert to expression
+      </Button>
+    </div>
+  }
+}