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

/**
 * Structural guarantees of the reference deployment (ADR 0044), checked on the files themselves so
 * an edit cannot quietly weaken them. `scripts/smoke-deploy.sh` proves the same configuration
 * actually runs; this proves it still says what the documentation promises.
 */

interface ComposeService {
  build?: unknown;
  cap_add?: string[];
  cap_drop?: string[];
  command?: string[];
  env_file?: string[];
  environment?: Record<string, string>;
  healthcheck?: { disable?: boolean };
  image?: string;
  init?: boolean;
  networks?: Record<string, { ipv4_address?: string } | null>;
  ports?: string[];
  profiles?: string[];
  read_only?: boolean;
  security_opt?: string[];
  tmpfs?: string[];
}

interface ComposeDocument {
  networks?: Record<
    string,
    { internal?: boolean; ipam?: { config?: { subnet?: string; ip_range?: string }[] } }
  >;
  services?: Record<string, ComposeService>;
}

const repositoryRoot = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "..");
const deployDirectory = path.join(repositoryRoot, "deploy");

async function compose(file: string): Promise<ComposeDocument> {
  // `merge: true` resolves the base file's `<<:` hardening anchors exactly as Compose does.
  return parse(await readFile(path.join(deployDirectory, file), "utf8"), {
    merge: true,
  }) as ComposeDocument;
}

async function text(file: string): Promise<string> {
  return readFile(path.join(deployDirectory, file), "utf8");
}

function envAssignments(source: string): Map<string, string> {
  const assignments = new Map<string, string>();
  for (const line of source.split("\n")) {
    const match = /^([A-Z][A-Z0-9_]*)=(.*)$/u.exec(line);
    if (match?.[1]) {
      assignments.set(match[1], match[2] ?? "");
    }
  }
  return assignments;
}

const DIGEST_PINNED = /^[^\s:@]+(?::[^\s@]+)?@sha256:[0-9a-f]{64}$/u;

describe("reference deployment compose files", () => {
  it("keeps PostgreSQL on its internal network only, and publishes no port from the base", async () => {
    const base = await compose("compose.yaml");
    const services = base.services ?? {};

    expect(Object.keys(services).sort()).toEqual(["api", "migrate", "object-storage", "postgres"]);
    expect(Object.keys(services.postgres?.networks ?? {})).toEqual(["data"]);
    expect(base.networks?.data?.internal).toBe(true);
    expect(base.networks?.storage?.internal).toBe(true);
    for (const [name, service] of Object.entries(services)) {
      expect(service.ports, name).toBeUndefined();
    }

    for (const overlay of ["compose.proxy.yaml", "compose.tunnel.yaml"]) {
      const document = await compose(overlay);
      expect(document.services?.postgres, overlay).toBeUndefined();
    }
  });

  it("pins every third-party image by digest and runs the API only from EKKLESIA_IMAGE", async () => {
    const documents = await Promise.all(
      ["compose.yaml", "compose.proxy.yaml", "compose.tunnel.yaml"].map(compose),
    );
    for (const document of documents) {
      for (const [name, service] of Object.entries(document.services ?? {})) {
        expect(service.build, name).toBeUndefined();
        if (service.image === undefined) {
          continue;
        }
        if (name === "api" || name === "migrate") {
          expect(service.image, name).toMatch(/^\$\{EKKLESIA_IMAGE:\?/u);
        } else {
          expect(service.image, name).toMatch(DIGEST_PINNED);
        }
      }
    }
  });

  it("hardens api and migrate, keeps migrate operator-only, and never lets it apply by default", async () => {
    const services = (await compose("compose.yaml")).services ?? {};
    for (const name of ["api", "migrate"]) {
      const service = services[name];
      expect(service?.init, name).toBe(true);
      expect(service?.read_only, name).toBe(true);
      expect(service?.tmpfs, name).toEqual(["/tmp"]);
      expect(service?.cap_drop, name).toEqual(["ALL"]);
      expect(service?.security_opt, name).toContain("no-new-privileges:true");
      expect(service?.environment?.NODE_EXTRA_CA_CERTS, name).toBe("/run/ekklesia/tls/ca.crt");
    }
    const migrate = services.migrate;
    expect(migrate?.profiles).toEqual(["ops"]);
    expect(migrate?.healthcheck?.disable).toBe(true);
    expect(migrate?.command).toEqual(["node", "core/dist/cli/plan-migrations.js"]);
    expect(JSON.stringify(services)).not.toContain("apply-migrations");
  });

  it("serves PostgreSQL and object storage over TLS from the installation-private CA", async () => {
    const services = (await compose("compose.yaml")).services ?? {};
    expect(services.postgres?.command).toEqual(
      expect.arrayContaining([
        "ssl=on",
        "ssl_min_protocol_version=TLSv1.3",
        "hba_file=/etc/ekklesia/pg_hba.conf",
      ]),
    );
    expect(services["object-storage"]?.command).toEqual(
      expect.arrayContaining(["-s3.port.https=8443"]),
    );

    const hba = (await text("postgres/pg_hba.conf"))
      .split("\n")
      .filter((line) => line.trim() !== "" && !line.trim().startsWith("#"))
      .map((line) => line.trim().split(/\s+/u));
    expect(hba).toEqual([
      ["local", "all", "all", "trust"],
      ["hostssl", "all", "all", "all", "scram-sha-256"],
      ["hostnossl", "all", "all", "all", "reject"],
    ]);
  });

  it("makes the proxy the API's only trusted peer, at a fixed address outside the dynamic range", async () => {
    const proxyOverlay = await compose("compose.proxy.yaml");
    const proxy = proxyOverlay.services?.proxy;
    const proxyAddress = proxy?.networks?.edge?.ipv4_address;
    expect(proxyAddress).toBe("${EKKLESIA_PROXY_ADDRESS:-10.249.250.254}");
    expect(proxyOverlay.services?.api?.environment).toEqual({
      EKKLESIA_CLIENT_ADDRESS_HEADER: "x-forwarded-for",
      EKKLESIA_CLIENT_ADDRESS_MODE: "trusted-proxy",
      EKKLESIA_CLIENT_ADDRESS_TRUSTED_PROXIES: `${proxyAddress}/32`,
    });
    expect(proxyOverlay.networks?.edge?.ipam?.config).toEqual([
      {
        ip_range: "${EKKLESIA_EDGE_DYNAMIC_RANGE:-10.249.250.0/25}",
        subnet: "${EKKLESIA_EDGE_SUBNET:-10.249.250.0/24}",
      },
    ]);
    expect(proxy?.cap_drop).toEqual(["ALL"]);
    expect(proxy?.cap_add).toEqual(["NET_BIND_SERVICE"]);

    const tunnel = (await compose("compose.tunnel.yaml")).services?.tunnel;
    expect(tunnel?.networks?.edge?.ipv4_address).toBe("${EKKLESIA_TUNNEL_ADDRESS:-10.249.250.253}");
    expect(tunnel?.env_file).toEqual(["${EKKLESIA_ENV_DIR:-/etc/ekklesia}/tunnel.env"]);
  });

  it("routes only the API's own paths, overwrites the forwarding header, and never ships local_certs", async () => {
    const caddyfile = await text("Caddyfile.example");
    const directives = caddyfile
      .split("\n")
      .filter((line) => !line.trim().startsWith("#"))
      .join("\n");

    expect(directives).toContain("@ekklesia path / /api/* /display/* /assets/*");
    expect(directives).toContain("header_up X-Forwarded-For {client_ip}");
    expect(directives).toContain("header_up -CF-Connecting-IP");
    expect(directives).toContain("trusted_proxies static {$EKKLESIA_TUNNEL_ADDRESS}/32");
    expect(directives).toContain("header_up Host {host}");
    expect(directives).toContain("tls_trust_pool file /etc/caddy/ekklesia-ca.crt");
    // Caddy's internal CA is a test-only substitution made by scripts/smoke-deploy.sh.
    expect(directives).not.toContain("local_certs");
    expect(directives).not.toMatch(/tls\s+internal/u);
  });
});

describe("reference deployment env examples", () => {
  it("contain no secret values", async () => {
    const secretKeys = new Map([
      ["env/ekklesia.env.example", ["EKKLESIA_IDENTITY_SECRET", "S3_ACCESS_KEY", "S3_SECRET_KEY"]],
      ["env/postgres.env.example", ["POSTGRES_PASSWORD"]],
      ["env/object-storage.env.example", ["AWS_ACCESS_KEY_ID", "AWS_SECRET_ACCESS_KEY"]],
      ["env/tunnel.env.example", ["TUNNEL_TOKEN"]],
    ]);
    for (const [file, keys] of secretKeys) {
      const assignments = envAssignments(await text(file));
      for (const key of keys) {
        expect(assignments.get(key), `${file} ${key}`).toBe("");
      }
    }
    const ekklesia = envAssignments(await text("env/ekklesia.env.example"));
    expect(ekklesia.get("DATABASE_URL")).toBe(
      "postgresql://<user>:<password>@postgres:5432/<database>",
    );
    expect(ekklesia.get("EKKLESIA_DATABASE_TLS_MODE")).toBe("verify-full");
    expect(ekklesia.get("S3_ENDPOINT")).toBe("https://object-storage:8443");
  });

  it("names every variable Core's host configuration reads", async () => {
    // The single place executables read the environment (core/src/host/configuration.ts). A new
    // variable there without a line here would leave an operator guessing.
    const hostConfiguration = await readFile(
      path.join(repositoryRoot, "core", "src", "host", "configuration.ts"),
      "utf8",
    );
    const read = new Set(
      [...hostConfiguration.matchAll(/environment\.([A-Z][A-Z0-9_]+)/gu)].map((match) => match[1]),
    );
    const example = await text("env/ekklesia.env.example");
    // Set by the image, not by an operator.
    read.delete("NODE_ENV");
    // Guards against a pattern that silently stops matching and checks nothing.
    expect(read.size).toBeGreaterThan(20);
    for (const name of read) {
      expect(example, String(name)).toMatch(new RegExp(`^#? ?${name}=`, "mu"));
    }
    expect(example).toContain("EKKLESIA_MODULE_SECRET__<MODULE_ID>__<KEY>=");
  });
});