import { readFileSync } from "node:fs";

import { describe, expect, it } from "vitest";

import {
  type ButtonSize,
  type ButtonVariant,
  buttonClass,
  type IconButtonSize,
  type IconButtonVariant,
  iconButtonClass,
} from "./buttonStyles";
import { type ChipSize, type ChipVariant, chipClass } from "./chipStyles";

// Tailwind generates CSS only for the class names it FINDS in the source, token by token. A class
// assembled at runtime (`${ACT}hover:text-fg`) is never found whole, so it ships with no rule at all:
// every hover colour of Button, IconButton and Chip was dead that way, found in an audit by
// reading the stylesheet (0 rules for `not-aria-disabled`). So: every class a primitive can emit has
// to stand in its source file whole, between the delimiters the scanner splits on.
const tokens = (file: string) =>
  new Set(readFileSync(new URL(file, import.meta.url), "utf8").split(/[\s"'`{}$]+/));

// Records, so a new variant or size that is not listed here fails to compile.
const keys = <K extends string>(r: Record<K, true>) => Object.keys(r) as K[];
const BV = keys<ButtonVariant>({
  primary: true, danger: true, warn: true, outline: true, "outline-accent": true,
  "outline-danger": true, "outline-warn": true, ghost: true, glass: true, overlay: true,
  media: true, "danger-soft": true, link: true, "link-muted": true,
}); // prettier-ignore
const BS = keys<ButtonSize>({ xs: true, sm: true, md: true, lg: true, none: true });
const IV = keys<IconButtonVariant>({
  ghost: true, "ghost-accent": true, primary: true, outline: true, "outline-accent": true,
  "outline-danger": true, "outline-warn": true, danger: true, "danger-soft": true, glass: true,
  media: true, overlay: true,
}); // prettier-ignore
const IS = keys<IconButtonSize>({ sm: true, md: true, lg: true, player: true });
const CV = keys<ChipVariant>({ filter: true, token: true, tag: true, suggest: true, ghost: true });
const CS = keys<ChipSize>({ md: true, sm: true, xs: true });

const missing = (emitted: string[], file: string) => {
  const found = tokens(file);
  return [...new Set(emitted.flatMap((c) => c.split(/\s+/)).filter(Boolean))].filter(
    (c) => !found.has(c),
  );
};

describe("every class a primitive emits is visible to the Tailwind scanner", () => {
  it("Button and IconButton", () => {
    const emitted: string[] = [];
    for (const pressed of [undefined, true]) {
      for (const variant of BV)
        for (const size of BS) emitted.push(buttonClass({ variant, size, pressed, round: true }));
      for (const variant of IV)
        for (const size of IS) emitted.push(iconButtonClass({ variant, size, pressed }));
    }
    expect(missing(emitted, "./buttonStyles.ts")).toEqual([]);
  });

  it("Chip", () => {
    const emitted = CV.flatMap((v) => CS.map((s) => chipClass(v, s)));
    expect(missing(emitted, "./chipStyles.ts")).toEqual([]);
  });
});