You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

137 lines
16 KiB

2 years ago
export class RangeTree {
constructor(start, end, delta, children) {
this.start = start;
this.end = end;
this.delta = delta;
this.children = children;
}
/**
* @precodition `ranges` are well-formed and pre-order sorted
*/
static fromSortedRanges(ranges) {
let root;
// Stack of parent trees and parent counts.
const stack = [];
for (const range of ranges) {
const node = new RangeTree(range.startOffset, range.endOffset, range.count, []);
if (root === undefined) {
root = node;
stack.push([node, range.count]);
continue;
}
let parent;
let parentCount;
while (true) {
[parent, parentCount] = stack[stack.length - 1];
// assert: `top !== undefined` (the ranges are sorted)
if (range.startOffset < parent.end) {
break;
}
else {
stack.pop();
}
}
node.delta -= parentCount;
parent.children.push(node);
stack.push([node, range.count]);
}
return root;
}
normalize() {
const children = [];
let curEnd;
let head;
const tail = [];
for (const child of this.children) {
if (head === undefined) {
head = child;
}
else if (child.delta === head.delta && child.start === curEnd) {
tail.push(child);
}
else {
endChain();
head = child;
}
curEnd = child.end;
}
if (head !== undefined) {
endChain();
}
if (children.length === 1) {
const child = children[0];
if (child.start === this.start && child.end === this.end) {
this.delta += child.delta;
this.children = child.children;
// `.lazyCount` is zero for both (both are after normalization)
return;
}
}
this.children = children;
function endChain() {
if (tail.length !== 0) {
head.end = tail[tail.length - 1].end;
for (const tailTree of tail) {
for (const subChild of tailTree.children) {
subChild.delta += tailTree.delta - head.delta;
head.children.push(subChild);
}
}
tail.length = 0;
}
head.normalize();
children.push(head);
}
}
/**
* @precondition `tree.start < value && value < tree.end`
* @return RangeTree Right part
*/
split(value) {
let leftChildLen = this.children.length;
let mid;
// TODO(perf): Binary search (check overhead)
for (let i = 0; i < this.children.length; i++) {
const child = this.children[i];
if (child.start < value && value < child.end) {
mid = child.split(value);
leftChildLen = i + 1;
break;
}
else if (child.start >= value) {
leftChildLen = i;
break;
}
}
const rightLen = this.children.length - leftChildLen;
const rightChildren = this.children.splice(leftChildLen, rightLen);
if (mid !== undefined) {
rightChildren.unshift(mid);
}
const result = new RangeTree(value, this.end, this.delta, rightChildren);
this.end = value;
return result;
}
/**
* Get the range coverages corresponding to the tree.
*
* The ranges are pre-order sorted.
*/
toRanges() {
const ranges = [];
// Stack of parent trees and counts.
const stack = [[this, 0]];
while (stack.length > 0) {
const [cur, parentCount] = stack.pop();
const count = parentCount + cur.delta;
ranges.push({ startOffset: cur.start, endOffset: cur.end, count });
for (let i = cur.children.length - 1; i >= 0; i--) {
stack.push([cur.children[i], count]);
}
}
return ranges;
}
}
//# sourceMappingURL=data:application/json;charset=utf8;base64,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