import { readdir, readFile } from "node:fs/promises";
import path from "node:path";
import { fileURLToPath } from "node:url";
import { describe, expect, it } from "vitest";

/**
 * Structural guarantees about email verification and password recovery that no runtime assertion can
 * make (ADR 0038).
 *
 * These read the repository itself, because what matters here is what code *exists* and what depends
 * on what: that identity never learns an SMTP detail, that no token store was reimplemented
 * alongside Better Auth's, that a device identity has no route into a human email flow, and that
 * nothing in a browser bundle can reach any of it.
 */
const repositoryRoot = path.join(path.dirname(fileURLToPath(import.meta.url)), "..", "..");

async function readTypeScriptFiles(
  directory: string,
): Promise<ReadonlyArray<{ readonly path: string; readonly text: string }>> {
  const results: Array<{ path: string; text: string }> = [];
  const walk = async (current: string): Promise<void> => {
    for (const entry of await readdir(current, { withFileTypes: true })) {
      const full = path.join(current, entry.name);
      if (entry.isDirectory()) {
        if (entry.name === "node_modules" || entry.name === "dist") {
          continue;
        }
        await walk(full);
        continue;
      }
      if (entry.name.endsWith(".ts") || entry.name.endsWith(".tsx")) {
        results.push({ path: full, text: await readFile(full, "utf8") });
      }
    }
  };
  await walk(path.join(repositoryRoot, directory));
  return results;
}

/** Strips block comments and whole-line `//` comments: these assertions are about code, and prose
 * explaining a rule inevitably quotes the token the rule forbids. */
function withoutComments(text: string): string {
  return text
    .replaceAll(/\/\*[\s\S]*?\*\//gu, "")
    .split("\n")
    .filter((line) => !line.trimStart().startsWith("//"))
    .join("\n");
}

describe("identity email flows stay above the mail transport", () => {
  it("names no SMTP or provider detail anywhere in the identity feature", async () => {
    for (const file of await readTypeScriptFiles(path.join("core", "src", "identity"))) {
      const code = withoutComments(file.text).toLowerCase();
      for (const forbidden of [
        "nodemailer",
        "smtpserver",
        "starttls",
        "createtransport",
        "587",
        "465",
      ]) {
        expect(code, `${file.path} names ${forbidden}`).not.toContain(forbidden);
      }
    }
  });

  it("reaches the transport only through the provider seam", async () => {
    const notifications = await readFile(
      path.join(repositoryRoot, "core", "src", "identity", "notifications.ts"),
      "utf8",
    );

    // The whole mail surface identity may use: a validated message and a `send`. Not a config, not
    // a transport, not a credential.
    expect(notifications).toContain('from "../mail/index.js"');
    expect(withoutComments(notifications)).not.toContain("MailProviderConfig");
    expect(withoutComments(notifications)).not.toContain("createSmtpMailProvider");
  });
});

describe("Better Auth owns every token", () => {
  it("adds no Ekklesia table, column, or store for a verification or reset token", async () => {
    const schemas = [
      path.join("core", "src", "identity", "schema.ts"),
      path.join("core", "src", "authorization", "schema.ts"),
      path.join("core", "src", "devices", "schema.ts"),
    ];

    for (const relative of schemas) {
      const code = withoutComments(
        await readFile(path.join(repositoryRoot, relative), "utf8"),
      ).toLowerCase();
      // A parallel token table would be a second expiry clock, a second consumption rule, and a
      // second thing to get wrong. `ekklesia_core_verification` is Better Auth's own table.
      expect(code, relative).not.toContain("reset_token");
      expect(code, relative).not.toContain("verification_token");
      expect(code, relative).not.toContain("password_reset");
    }
  });

  it("never hashes, stores, or compares a token itself", async () => {
    for (const file of await readTypeScriptFiles(path.join("core", "src", "identity"))) {
      const code = withoutComments(file.text);
      expect(code, file.path).not.toContain("createHash");
      expect(code, file.path).not.toContain("timingSafeEqual");
    }
  });

  it("interpolates no token, link, address, or message body into anything it logs", async () => {
    for (const file of await readTypeScriptFiles(path.join("core", "src", "identity"))) {
      const code = withoutComments(file.text);
      for (const call of code.matchAll(/console\.\w+\(([^\n]*)/gu)) {
        // Fixed prose in a log line is fine; a **substituted value** is what could carry a secret.
        // Only the interpolations are examined, so "email was not delivered" passes while
        // `${user.email}` could not.
        for (const substitution of (call[1] ?? "").matchAll(/\$\{([^}]*)\}/gu)) {
          const expression = (substitution[1] ?? "").toLowerCase();
          for (const forbidden of ["token", "url", "html", "text", "email", "recipient", "body"]) {
            expect(expression, `${file.path} logs ${forbidden}`).not.toContain(forbidden);
          }
        }
      }
    }
  });
});

describe("managed devices have no part in human email identity", () => {
  it("gives a device no address, password, or verification state", async () => {
    for (const file of await readTypeScriptFiles(path.join("core", "src", "devices"))) {
      const code = withoutComments(file.text).toLowerCase();
      for (const forbidden of ["email", "password", "emailverified", "sendresetpassword"]) {
        expect(code, `${file.path} names ${forbidden}`).not.toContain(forbidden);
      }
    }
  });

  it("keeps the device store out of the identity notification path entirely", async () => {
    const notifications = await readFile(
      path.join(repositoryRoot, "core", "src", "identity", "notifications.ts"),
      "utf8",
    );

    expect(notifications).not.toContain("devices");
    expect(notifications).not.toContain("Device");
  });
});

describe("the browser shell reaches none of it", () => {
  it("imports neither Better Auth nor Core's mail from any browser source", async () => {
    for (const file of await readTypeScriptFiles(path.join("surfaces", "shell", "src"))) {
      expect(file.text, file.path).not.toContain("better-auth");
      expect(file.text, file.path).not.toContain("@ekklesia/core/mail");
      expect(file.text, file.path).not.toContain("nodemailer");
    }
  });

  it("declares no server identity or mail dependency in the shell package", async () => {
    const manifest = JSON.parse(
      await readFile(path.join(repositoryRoot, "surfaces", "shell", "package.json"), "utf8"),
    ) as Record<string, Record<string, string> | undefined>;
    const declared = Object.keys({
      ...(manifest.dependencies ?? {}),
      ...(manifest.devDependencies ?? {}),
    });

    expect(declared).not.toContain("better-auth");
    expect(declared).not.toContain("nodemailer");
    expect(declared).not.toContain("@ekklesia/core");
  });

  it("never puts a reset token in browser storage", async () => {
    for (const file of await readTypeScriptFiles(path.join("surfaces", "shell", "src"))) {
      const code = withoutComments(file.text);
      // A reset token is a bearer credential for one account; the shell holds it in React state for
      // the life of one form and nowhere else.
      expect(code, file.path).not.toContain("localStorage");
      expect(code, file.path).not.toContain("sessionStorage");
      expect(code, file.path).not.toContain("document.cookie");
    }
  });
});

describe("public signup stays gone", () => {
  it("offers no registration path from any browser source", async () => {
    for (const file of await readTypeScriptFiles(path.join("surfaces", "shell", "src"))) {
      const code = withoutComments(file.text);
      // Email verification is not a licence to self-register (ADR 0038).
      expect(code, file.path).not.toContain("/sign-up");
      expect(code, file.path).not.toContain("signUp");
    }
  });
});