Convert editor to TypeScript

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

src/editor/range.ts

@@ -0,0 +1,96 @@
+/*
+Copyright 2019 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import EditorModel from "./model";
+import DocumentPosition from "./position";
+
+export default class Range {
+    private _start: DocumentPosition;
+    private _end: DocumentPosition;
+
+    constructor(public readonly model: EditorModel, positionA: DocumentPosition, positionB = positionA) {
+        const bIsLarger = positionA.compare(positionB) < 0;
+        this._start = bIsLarger ? positionA : positionB;
+        this._end = bIsLarger ? positionB : positionA;
+    }
+
+    moveStart(delta) {
+        this._start = this._start.forwardsWhile(this.model, () => {
+            delta -= 1;
+            return delta >= 0;
+        });
+    }
+
+    expandBackwardsWhile(predicate) {
+        this._start = this._start.backwardsWhile(this.model, predicate);
+    }
+
+    get text() {
+        let text = "";
+        this._start.iteratePartsBetween(this._end, this.model, (part, startIdx, endIdx) => {
+            const t = part.text.substring(startIdx, endIdx);
+            text = text + t;
+        });
+        return text;
+    }
+
+    /**
+     * Splits the model at the range boundaries and replaces with the given parts.
+     * Should be run inside a `model.transform()` callback.
+     * @param {Part[]} parts the parts to replace the range with
+     * @return {Number} the net amount of characters added, can be negative.
+     */
+    replace(parts) {
+        const newLength = parts.reduce((sum, part) => sum + part.text.length, 0);
+        let oldLength = 0;
+        this._start.iteratePartsBetween(this._end, this.model, (part, startIdx, endIdx) => {
+            oldLength += endIdx - startIdx;
+        });
+        this.model.replaceRange(this._start, this._end, parts);
+        return newLength - oldLength;
+    }
+
+    /**
+     * Returns a copy of the (partial) parts within the range.
+     * For partial parts, only the text is adjusted to the part that intersects with the range.
+     */
+    get parts() {
+        const parts = [];
+        this._start.iteratePartsBetween(this._end, this.model, (part, startIdx, endIdx) => {
+            const serializedPart = part.serialize();
+            serializedPart.text = part.text.substring(startIdx, endIdx);
+            const newPart = this.model.partCreator.deserializePart(serializedPart);
+            parts.push(newPart);
+        });
+        return parts;
+    }
+
+    get length() {
+        let len = 0;
+        this._start.iteratePartsBetween(this._end, this.model, (part, startIdx, endIdx) => {
+            len += endIdx - startIdx;
+        });
+        return len;
+    }
+
+    get start() {
+        return this._start;
+    }
+
+    get end() {
+        return this._end;
+    }
+}