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import { ResolveType, ZipKeysWithValues } from './types.js';
export type valueof<K> = K[keyof K];
export function keysOf<T extends string>(obj: { [k in T]: unknown }): readonly T[] {
return Object.keys(obj) as unknown[] as T[];
}
export function numericKeysOf<T>(obj: object): readonly T[] {
return Object.keys(obj).map(n => Number(n)) as unknown[] as T[];
}
/**
* @returns a new Record from `objects`, using the string returned by Object.toString() as the keys
* and the objects as the values.
*/
export function objectsToRecord<T extends Object>(objects: readonly T[]): Record<string, T> {
const record = {};
return objects.reduce((obj, type) => {
return {
...obj,
[type.toString()]: type,
};
}, record);
}
/**
* Creates an info lookup object from a more nicely-formatted table. See below for examples.
*
* Note: Using `as const` on the arguments to this function is necessary to infer the correct type.
*/
export function makeTable<
Members extends readonly string[],
Defaults extends readonly unknown[],
Table extends { readonly [k: string]: readonly unknown[] },
>(
members: Members,
defaults: Defaults,
table: Table
): {
readonly [k in keyof Table]: ResolveType<ZipKeysWithValues<Members, Table[k], Defaults>>;
} {
const result: { [k: string]: { [m: string]: unknown } } = {};
for (const [k, v] of Object.entries<readonly unknown[]>(table)) {
const item: { [m: string]: unknown } = {};
for (let i = 0; i < members.length; ++i) {
item[members[i]] = v[i] ?? defaults[i];
}
result[k] = item;
}
/* eslint-disable-next-line @typescript-eslint/no-explicit-any */
return result as any;
}
/**
* Creates an info lookup object from a more nicely-formatted table.
*
* Note: Using `as const` on the arguments to this function is necessary to infer the correct type.
*
* Example:
*
* ```
* const t = makeTableWithDefaults(
* { c: 'default' }, // columnRenames
* ['a', 'default', 'd'], // columnsKept
* ['a', 'b', 'c', 'd'], // columns
* [123, 456, 789, 1011], // defaults
* { // table
* foo: [1, 2, 3, 4],
* bar: [5, , , 8],
* moo: [ , 9,10, ],
* }
* );
*
* // t = {
* // foo: { a: 1, default: 3, d: 4 },
* // bar: { a: 5, default: 789, d: 8 },
* // moo: { a: 123, default: 10, d: 1011 },
* // };
* ```
*
* MAINTENANCE_TODO: `ZipKeysWithValues<Members, Table[k], Defaults>` is incorrect
* because Members no longer maps to Table[k]. It's not clear if this is even possible to fix
* because it requires mapping, not zipping. Maybe passing in a index mapping
* would fix it (which is gross) but if you have columnsKept as [0, 2, 3] then maybe it would
* be possible to generate the correct type? I don't think we can generate the map at compile time
* so we'd have to hand code it. Other ideas, don't generate kLimitsInfoCore and kLimitsInfoCompat
* where they are keys of infos. Instead, generate kLimitsInfoCoreDefaults, kLimitsInfoCoreMaximums,
* kLimitsInfoCoreClasses where each is just a `{[k: string]: type}`. Could zip those after or,
* maybe that suggests passing in the hard coded indices would work.
*
* @param columnRenames the name of the column in the table that will be assigned to the 'default' property of each entry.
* @param columnsKept the names of properties you want in the generated lookup table. This must be a subset of the columns of the tables except for the name 'default' which is looked from the previous argument.
* @param columns the names of the columns of the name
* @param defaults the default value by column for any element in a row of the table that is undefined
* @param table named table rows.
*/
export function makeTableRenameAndFilter<
Members extends readonly string[],
DataMembers extends readonly string[],
Defaults extends readonly unknown[],
Table extends { readonly [k: string]: readonly unknown[] },
>(
columnRenames: { [key: string]: string },
columnsKept: Members,
columns: DataMembers,
defaults: Defaults,
table: Table
): {
readonly [k in keyof Table]: ResolveType<ZipKeysWithValues<Members, Table[k], Defaults>>;
} {
const result: { [k: string]: { [m: string]: unknown } } = {};
const keyToIndex = new Map<string, number>(
columnsKept.map(name => {
const remappedName = columnRenames[name] === undefined ? name : columnRenames[name];
return [name, columns.indexOf(remappedName)];
})
);
for (const [k, v] of Object.entries<readonly unknown[]>(table)) {
const item: { [m: string]: unknown } = {};
for (const member of columnsKept) {
const ndx = keyToIndex.get(member)!;
item[member] = v[ndx] ?? defaults[ndx];
}
result[k] = item;
}
/* eslint-disable-next-line @typescript-eslint/no-explicit-any */
return result as any;
}