import { execFile } from "node:child_process";
import { cp, mkdtemp, readdir, readFile, rm, writeFile } from "node:fs/promises";
import { tmpdir } from "node:os";
import path from "node:path";
import { fileURLToPath } from "node:url";
import { promisify } from "node:util";
import { afterAll, beforeAll, describe, expect, it } from "vitest";

/**
 * Browser-native dialogs — `alert`, `confirm`, `prompt` — are prohibited in product UI (DESIGN.md
 * §8.1, ADR 0059). The guard is repository-wide and two-part:
 *
 * 1. Biome's scope-aware `suspicious/noAlert`, an error in the root `biome.json`, so `pnpm lint`
 *    refuses a dialog call anywhere in this repository — the shell, `@ekklesia/ui`, the module
 *    template — while leaving a local function or a method that shares the name alone.
 * 2. A narrow scan of browser source for the two forms that rule cannot see: a call through `self`,
 *    `top`, `parent`, or `frames`, and borrowing the function without calling it.
 *
 * This file proves both against fixtures, with the repository's own lint configuration, so the
 * guard is shown to catch real usage and to stay quiet about lookalikes.
 */

const execFileAsync = promisify(execFile);
const repositoryRoot = path.dirname(path.dirname(fileURLToPath(import.meta.url)));
const fixtures = path.join(repositoryRoot, "tests", "fixtures", "native-dialogs");
const biome = path.join(repositoryRoot, "node_modules", ".bin", "biome");

/** Where browser code lives in this repository. */
const BROWSER_SOURCE_ROOTS = [
  "surfaces",
  path.join("packages", "ui", "src"),
  path.join("packages", "module-ui-sdk", "src"),
  path.join("packages", "module-ui-host", "src"),
  path.join("templates", "module", "src"),
];

/** A dialog reached through a window alias, called or not: `self.prompt(`, `= window.confirm;`. */
const DIALOG_THROUGH_A_WINDOW =
  /\b(?:window|globalThis|self|top|parent|frames)\s*(?:\.\s*|\[\s*["'`])(?:alert|confirm|prompt)\b/u;

function withoutComments(source: string): string {
  return source.replace(/\/\*[\s\S]*?\*\//gu, "").replace(/(^|[^:\\])\/\/.*$/gmu, "$1");
}

/** Lines that reach a dialog in a way Biome's rule does not report. */
function scan(source: string): number[] {
  return withoutComments(source)
    .split("\n")
    .flatMap((line, index) => {
      const code = line.replace(/\/(?:\\.|[^/\n])+\/[a-z]*/gu, "").replace(/"[^"]*"|'[^']*'/gu, "");
      return DIALOG_THROUGH_A_WINDOW.test(code) ? [index + 1] : [];
    });
}

async function sourceFiles(directory: string): Promise<string[]> {
  const entries = await readdir(directory, { withFileTypes: true }).catch(() => []);
  const files: string[] = [];
  for (const entry of entries) {
    const full = path.join(directory, entry.name);
    if (entry.isDirectory()) {
      if (!["node_modules", "dist", ".turbo", "tests", "test"].includes(entry.name)) {
        files.push(...(await sourceFiles(full)));
      }
    } else if (/\.(?:ts|tsx|js|jsx|mjs)$/u.test(entry.name)) {
      files.push(full);
    }
  }
  return files;
}

let workspace: string;

/** Lints a fixture with exactly the root configuration's rules, from a directory the root
 * configuration's own `files.includes` does not exclude. */
async function lint(
  fixture: string,
): Promise<Array<{ readonly line: number; readonly rule: string }>> {
  try {
    await execFileAsync(biome, ["lint", "--max-diagnostics=100", fixture], {
      cwd: workspace,
    });
    return [];
  } catch (error) {
    const output = `${(error as { stdout?: string }).stdout ?? ""}${(error as { stderr?: string }).stderr ?? ""}`;
    return [...output.matchAll(/^\S*?(\d+):\d+ (lint\/\S+)/gmu)].map((match) => ({
      line: Number(match[1]),
      rule: match[2] ?? "",
    }));
  }
}

beforeAll(async () => {
  workspace = await mkdtemp(path.join(tmpdir(), "ekklesia-native-dialogs-"));
  const config = JSON.parse(await readFile(path.join(repositoryRoot, "biome.json"), "utf8")) as {
    files?: unknown;
  };
  delete config.files;
  await writeFile(path.join(workspace, "biome.json"), JSON.stringify(config));
  await cp(fixtures, workspace, { recursive: true });
});

afterAll(async () => {
  await rm(workspace, { force: true, recursive: true });
});

describe("the repository's lint refuses browser-native dialogs", () => {
  it("makes noAlert an error in the root configuration", async () => {
    const config = JSON.parse(await readFile(path.join(repositoryRoot, "biome.json"), "utf8")) as {
      linter?: { rules?: { suspicious?: { noAlert?: unknown } } };
    };
    expect(config.linter?.rules?.suspicious?.noAlert).toBe("error");
  });

  it("reports every dialog call", async () => {
    const findings = await lint("prohibited.ts");

    expect(findings.filter((finding) => finding.rule === "lint/suspicious/noAlert")).toEqual(
      [2, 3, 4, 5, 6, 7, 8, 9].map((line) => ({ line, rule: "lint/suspicious/noAlert" })),
    );
  }, 30_000);

  it("reports nothing about a local function, a method, a property, a string, or a comment", async () => {
    expect(await lint("permitted.ts")).toEqual([]);
  }, 30_000);
});

describe("the repository scan covers what the lint rule cannot see", () => {
  it("catches a dialog called through self, or borrowed without being called", async () => {
    const source = await readFile(path.join(fixtures, "prohibited-references.ts"), "utf8");
    expect(scan(source)).toEqual([2, 3]);
  });

  it("stays quiet about the permitted fixture", async () => {
    const source = await readFile(path.join(fixtures, "permitted.ts"), "utf8");
    expect(scan(source)).toEqual([]);
  });

  it("finds no dialog anywhere in this repository's browser source", async () => {
    const offenders: string[] = [];
    let scanned = 0;
    for (const sourceRoot of BROWSER_SOURCE_ROOTS) {
      for (const file of await sourceFiles(path.join(repositoryRoot, sourceRoot))) {
        scanned += 1;
        for (const line of scan(await readFile(file, "utf8"))) {
          offenders.push(`${path.relative(repositoryRoot, file)}:${line}`);
        }
      }
    }
    expect(scanned).toBeGreaterThan(20);
    expect(offenders).toEqual([]);
  });
});