171 lines
4.5 KiB
JavaScript
171 lines
4.5 KiB
JavaScript
/*
|
|
MIT License http://www.opensource.org/licenses/mit-license.php
|
|
Author Tobias Koppers @sokra
|
|
*/
|
|
|
|
"use strict";
|
|
|
|
/**
|
|
* @typedef {Object} GroupOptions
|
|
* @property {boolean=} groupChildren
|
|
* @property {boolean=} force
|
|
* @property {number=} targetGroupCount
|
|
*/
|
|
|
|
/**
|
|
* @template T
|
|
* @template R
|
|
* @typedef {Object} GroupConfig
|
|
* @property {function(T): string[]} getKeys
|
|
* @property {function(string, (R | T)[], T[]): R} createGroup
|
|
* @property {function(string, T[]): GroupOptions=} getOptions
|
|
*/
|
|
|
|
/**
|
|
* @template T
|
|
* @typedef {Object} ItemWithGroups
|
|
* @property {T} item
|
|
* @property {Set<string>} groups
|
|
*/
|
|
|
|
/**
|
|
* @template T
|
|
* @template R
|
|
* @param {T[]} items the list of items
|
|
* @param {GroupConfig<T, R>[]} groupConfigs configuration
|
|
* @returns {(R | T)[]} grouped items
|
|
*/
|
|
const smartGrouping = (items, groupConfigs) => {
|
|
/** @type {Set<ItemWithGroups<T>>} */
|
|
const itemsWithGroups = new Set();
|
|
/** @type {Map<string, [GroupConfig<T, R>, string]>} */
|
|
const groupConfigMap = new Map();
|
|
for (const item of items) {
|
|
const groups = new Set();
|
|
for (let i = 0; i < groupConfigs.length; i++) {
|
|
const groupConfig = groupConfigs[i];
|
|
const keys = groupConfig.getKeys(item);
|
|
if (keys) {
|
|
for (const group of keys) {
|
|
const fullGroup = `${i}:${group}`;
|
|
if (!groupConfigMap.has(fullGroup)) {
|
|
groupConfigMap.set(fullGroup, [groupConfig, group]);
|
|
}
|
|
groups.add(fullGroup);
|
|
}
|
|
}
|
|
}
|
|
itemsWithGroups.add({
|
|
item,
|
|
groups
|
|
});
|
|
}
|
|
const alreadyGrouped = new Set();
|
|
/**
|
|
* @param {Set<ItemWithGroups<T>>} itemsWithGroups input items with groups
|
|
* @returns {(T | R)[]} groups items
|
|
*/
|
|
const runGrouping = itemsWithGroups => {
|
|
const totalSize = itemsWithGroups.size;
|
|
/** @type {Map<string, Set<ItemWithGroups<T>>>} */
|
|
const groupMap = new Map();
|
|
for (const entry of itemsWithGroups) {
|
|
for (const group of entry.groups) {
|
|
if (alreadyGrouped.has(group)) continue;
|
|
const list = groupMap.get(group);
|
|
if (list === undefined) {
|
|
groupMap.set(group, new Set([entry]));
|
|
} else {
|
|
list.add(entry);
|
|
}
|
|
}
|
|
}
|
|
/** @type {Set<string>} */
|
|
const usedGroups = new Set();
|
|
/** @type {(T | R)[]} */
|
|
const results = [];
|
|
for (;;) {
|
|
let bestGroup = undefined;
|
|
let bestGroupSize = -1;
|
|
let bestGroupItems = undefined;
|
|
let bestGroupOptions = undefined;
|
|
for (const [group, items] of groupMap) {
|
|
if (items.size === 0) continue;
|
|
const [groupConfig, groupKey] = groupConfigMap.get(group);
|
|
const options =
|
|
groupConfig.getOptions &&
|
|
groupConfig.getOptions(
|
|
groupKey,
|
|
Array.from(items, ({ item }) => item)
|
|
);
|
|
const force = options && options.force;
|
|
if (!force) {
|
|
if (bestGroupOptions && bestGroupOptions.force) continue;
|
|
if (usedGroups.has(group)) continue;
|
|
if (items.size <= 1 || totalSize - items.size <= 1) {
|
|
continue;
|
|
}
|
|
}
|
|
const targetGroupCount = (options && options.targetGroupCount) || 4;
|
|
let sizeValue = force
|
|
? items.size
|
|
: Math.min(
|
|
items.size,
|
|
(totalSize * 2) / targetGroupCount +
|
|
itemsWithGroups.size -
|
|
items.size
|
|
);
|
|
if (
|
|
sizeValue > bestGroupSize ||
|
|
(force && (!bestGroupOptions || !bestGroupOptions.force))
|
|
) {
|
|
bestGroup = group;
|
|
bestGroupSize = sizeValue;
|
|
bestGroupItems = items;
|
|
bestGroupOptions = options;
|
|
}
|
|
}
|
|
if (bestGroup === undefined) {
|
|
break;
|
|
}
|
|
const items = new Set(bestGroupItems);
|
|
const options = bestGroupOptions;
|
|
|
|
const groupChildren = !options || options.groupChildren !== false;
|
|
|
|
for (const item of items) {
|
|
itemsWithGroups.delete(item);
|
|
// Remove all groups that items have from the map to not select them again
|
|
for (const group of item.groups) {
|
|
const list = groupMap.get(group);
|
|
if (list !== undefined) list.delete(item);
|
|
if (groupChildren) {
|
|
usedGroups.add(group);
|
|
}
|
|
}
|
|
}
|
|
groupMap.delete(bestGroup);
|
|
|
|
const idx = bestGroup.indexOf(":");
|
|
const configKey = bestGroup.slice(0, idx);
|
|
const key = bestGroup.slice(idx + 1);
|
|
const groupConfig = groupConfigs[+configKey];
|
|
|
|
const allItems = Array.from(items, ({ item }) => item);
|
|
|
|
alreadyGrouped.add(bestGroup);
|
|
const children = groupChildren ? runGrouping(items) : allItems;
|
|
alreadyGrouped.delete(bestGroup);
|
|
|
|
results.push(groupConfig.createGroup(key, children, allItems));
|
|
}
|
|
for (const { item } of itemsWithGroups) {
|
|
results.push(item);
|
|
}
|
|
return results;
|
|
};
|
|
return runGrouping(itemsWithGroups);
|
|
};
|
|
|
|
module.exports = smartGrouping;
|