import { readFileSync } from "node:fs";
import { join } from "node:path";
import { describe, expect, it } from "vitest";

const source = readFileSync(
  join(import.meta.dirname, "../src/tailwind.css"),
  "utf8"
);

function block(selector: string): string {
  const at = source.indexOf(`\n${selector} {`);
  if (at === -1) {
    return "";
  }
  const open = source.indexOf("{", at);
  const close = source.indexOf("\n}", open);
  return source.slice(open, close);
}

describe("theme aliases", () => {
  const OBSIDIAN_VARS = [
    "--background-primary",
    "--background-secondary",
    "--background-modifier-border",
    "--text-normal",
    "--text-muted",
    "--color-accent",
    "--text-on-accent",
    "--text-error",
  ];

  it("are declared on .beaver-root, not :root", () => {
    const root = block(".beaver-root");
    expect(root).not.toBe("");
    for (const name of OBSIDIAN_VARS) {
      expect(root, `${name} must be aliased on .beaver-root`).toContain(name);
    }
  });

  it("never reference Obsidian variables from :root", () => {
    const rootBlocks = [...source.matchAll(/(^|\n):root\s*\{([^}]*)\}/g)];
    for (const [, , body] of rootBlocks) {
      for (const name of OBSIDIAN_VARS) {
        expect(body, `:root must not reference ${name}`).not.toContain(name);
      }
    }
  });

  it("scopes the dark override under the view root", () => {
    expect(source).toContain(".theme-dark .beaver-root");
    expect(source).not.toMatch(/\n\.theme-dark\s*\{/);
  });

  it("keeps the msos palette out: the live accent is Obsidian's", () => {
    const root = block(".beaver-root");
    expect(root).toContain("--signal: var(--color-accent)");
    expect(root).toContain("--primary: var(--color-accent)");
    expect(root).not.toMatch(/oklch\([^)]*\s34[0-2]\)/);
  });
});

describe("reset specificity", () => {
  it("uses a doubled class to outrank app and theme styles", () => {
    expect(source).toContain(".beaver-root.beaver-root");
  });

  it("gives every control Obsidian's corner language", () => {
    expect(source).toContain('[data-slot="button"]');
    expect(source).toContain("var(--button-radius");
    expect(source).toContain('[data-slot="input"]');
  });
});

describe("cascade against Obsidian", () => {
  it("marks utilities important so they outrank app.css", () => {
    expect(source).toMatch(
      /@import "tailwindcss\/utilities\.css"[^;]*\bimportant\b/
    );
  });

  it("scans the shared panel sources", () => {
    expect(source).toContain('@source "../../beaver-gateway/ui/src/lib"');
    expect(source).toContain("panel/panel.css");
  });

  it("imports only the theme and utility layers", () => {
    expect(source).toContain('@import "tailwindcss/theme.css"');
    expect(source).toContain('@import "tailwindcss/utilities.css"');
    expect(source).not.toMatch(/@import "tailwindcss"\s*[;l]/);
    expect(source).not.toMatch(/@import\s+"tailwindcss\/preflight/);
  });
});