import { randomBytes } from "node:crypto";
import { mkdtemp, rm } from "node:fs/promises";
import { tmpdir } from "node:os";
import path from "node:path";
import { fileURLToPath } from "node:url";
import { parseModuleManifest } from "@ekklesia/contracts";
import { Client, type QueryResultRow } from "pg";
import { afterAll, describe, expect, it } from "vitest";
import { createValidatedPostgresPool } from "../src/database/index.js";
import {
  applyModuleMigrations,
  createPostgresMigrationDatabase,
  discoverAllMigrations,
} from "../src/migrations/index.js";
import {
  createModuleConfigurationStore,
  createModuleConfigurationView,
  type ModuleConfigurationStore,
  ModuleConfigurationStoreError,
  resolveModuleConfigurationFor,
} from "../src/modules/index.js";

/**
 * The module configuration store against real PostgreSQL.
 *
 * `core/tests/module-configuration.test.ts` proves the validation and defaulting rules with no
 * database at all; this proves the things only a database can: that migration `0005` really creates
 * the table with the composite primary key and value ceiling the schema declares, that a replace is
 * transactional and scoped to one module, that stored values survive a completely new connection,
 * and — the security-relevant one — that a module id or key is only ever *data* in a parameterized
 * column, never an SQL identifier. The in-memory double the API route tests use reproduces none of
 * that, which is why it lives here.
 */
const integrationDatabaseUrlEnvironment = "EKKLESIA_MIGRATION_TEST_DATABASE_URL";
const coreMigrationsDirectory = path.join(
  path.dirname(fileURLToPath(import.meta.url)),
  "..",
  "drizzle",
);
const trackedDatabases = new Set<string>();
let databaseCounter = 0;

class IntegrationHarnessError extends Error {
  constructor(message: string) {
    super(message);
    this.name = "IntegrationHarnessError";
    this.stack = `${this.name}: ${this.message}`;
  }
}

function harnessError(message: string): IntegrationHarnessError {
  return new IntegrationHarnessError(message);
}

function baseDatabaseUrl(): string {
  const value = process.env[integrationDatabaseUrlEnvironment];
  if (typeof value !== "string" || value.trim() === "") {
    throw harnessError("The module configuration integration database is not configured.");
  }
  try {
    const parsed = new URL(value);
    if (parsed.protocol !== "postgres:" && parsed.protocol !== "postgresql:") {
      throw new TypeError("Unsupported protocol.");
    }
  } catch {
    throw harnessError("The module configuration integration database configuration is invalid.");
  }
  return value;
}

function quoteDatabaseName(databaseName: string): string {
  if (!/^[a-z][a-z0-9_]{0,62}$/u.test(databaseName)) {
    throw harnessError("The generated integration database name is invalid.");
  }
  return `"${databaseName}"`;
}

function makeDatabaseName(label: string): string {
  const safeLabel = label
    .toLowerCase()
    .replaceAll(/[^a-z0-9]+/gu, "_")
    .replaceAll(/^_+|_+$/gu, "")
    .slice(0, 10);
  databaseCounter += 1;
  return `ekk_modcfg_${process.pid}_${databaseCounter}_${safeLabel || "scenario"}_${randomBytes(4).toString("hex")}`;
}

function databaseUrl(databaseName: string): string {
  const parsed = new URL(baseDatabaseUrl());
  parsed.pathname = `/${databaseName}`;
  parsed.searchParams.delete("application_name");
  return parsed.toString();
}

async function openAdministrativeClient(connectionString: string): Promise<Client> {
  const client = new Client({ connectionString });
  client.on("error", () => undefined);
  try {
    await client.connect();
    return client;
  } catch {
    try {
      await client.end();
    } catch {
      // The public harness failure stays static when connection cleanup also fails.
    }
    throw harnessError("The module configuration integration database connection failed.");
  }
}

async function safeQuery<Row extends QueryResultRow>(
  client: Client,
  text: string,
  values: unknown[] = [],
): Promise<readonly Row[]> {
  try {
    const result = await client.query<Row>(text, values);
    return result.rows;
  } catch {
    throw harnessError("An integration database administration operation failed.");
  }
}

async function safeEnd(client: Client): Promise<void> {
  try {
    await client.end();
  } catch {
    throw harnessError("An integration database connection could not be closed.");
  }
}

async function dropDatabase(databaseName: string): Promise<void> {
  const admin = await openAdministrativeClient(baseDatabaseUrl());
  try {
    await safeQuery(
      admin,
      "SELECT pg_terminate_backend(pid) FROM pg_stat_activity WHERE datname = $1 AND pid <> pg_backend_pid()",
      [databaseName],
    );
    await safeQuery(
      admin,
      `DROP DATABASE IF EXISTS ${quoteDatabaseName(databaseName)} WITH (FORCE)`,
    );
    trackedDatabases.delete(databaseName);
  } finally {
    await safeEnd(admin);
  }
}

async function createDisposableDatabase(label: string): Promise<{ name: string; url: string }> {
  const name = makeDatabaseName(label);
  const admin = await openAdministrativeClient(baseDatabaseUrl());
  try {
    await safeQuery(admin, `CREATE DATABASE ${quoteDatabaseName(name)} TEMPLATE template0`);
  } finally {
    await safeEnd(admin);
  }
  trackedDatabases.add(name);
  return { name, url: databaseUrl(name) };
}

async function applyCoreMigrations(url: string): Promise<void> {
  const emptyModulesDirectory = await mkdtemp(path.join(tmpdir(), "ekklesia-modcfg-no-modules-"));
  try {
    const aggregate = await discoverAllMigrations({
      coreMigrationsDirectory,
      moduleDiscovery: {
        moduleSdkVersion: "0.1.0",
        modulesDirectory: emptyModulesDirectory,
        platformVersion: "0.1.0",
      },
    });
    expect(aggregate.migrations.map((entry) => entry.identity)).toEqual([
      "core:0000_identity_core_tables",
      "core:0001_authorization_core_tables",
      "core:0002_authorization_integrity",
      "core:0003_dashboard_navigation_tables",
      "core:0004_module_lifecycle_state",
      "core:0005_module_configuration",
      "core:0006_device_identity",
      "core:0007_verified_bootstrap_owners",
    ]);
    await applyModuleMigrations({ aggregate, database: createPostgresMigrationDatabase(url) });
  } finally {
    await rm(emptyModulesDirectory, { force: true, recursive: true });
  }
}

afterAll(async () => {
  for (const databaseName of [...trackedDatabases]) {
    await dropDatabase(databaseName).catch(() => undefined);
  }
});

function manifestWith(configuration: readonly Record<string, unknown>[], id = "announcements") {
  return parseModuleManifest({
    manifestVersion: 6,
    id,
    name: `${id} module`,
    version: "1.0.0",
    compatibility: { platform: "^0.1.0", moduleSdk: "^0.1.0" },
    configuration,
    entrypoints: { server: "./dist/does-not-exist/index.js" },
  });
}

describe.sequential("live Core module configuration store", () => {
  let database: { name: string; url: string };
  let admin: Client;
  let store: ModuleConfigurationStore;
  let close: () => Promise<void>;

  it("creates exactly the one configuration table, with its composite key and declared constraints", async () => {
    database = await createDisposableDatabase("fresh");
    await applyCoreMigrations(database.url);
    admin = await openAdministrativeClient(database.url);

    const columns = await safeQuery<{ column_name: string; is_nullable: string }>(
      admin,
      `select column_name, is_nullable
         from information_schema.columns
        where table_name = 'ekklesia_core_module_configuration'
        order by column_name`,
    );
    const primaryKey = await safeQuery<{ column_name: string }>(
      admin,
      `select kcu.column_name
         from information_schema.table_constraints tc
         join information_schema.key_column_usage kcu
           on kcu.constraint_name = tc.constraint_name
        where tc.table_name = 'ekklesia_core_module_configuration'
          and tc.constraint_type = 'PRIMARY KEY'
        order by kcu.ordinal_position`,
    );
    // Only the explicitly declared CHECKs: PostgreSQL 17 also materializes a system `..._not_null`
    // CHECK per NOT NULL column, which is not something this schema declares.
    const checks = await safeQuery<{ constraint_name: string }>(
      admin,
      `select tc.constraint_name
         from information_schema.table_constraints tc
        where tc.table_name = 'ekklesia_core_module_configuration'
          and tc.constraint_type = 'CHECK'
          and tc.constraint_name not like '%_not_null'
        order by tc.constraint_name`,
    );

    expect(columns.map((column) => column.column_name)).toEqual([
      "created_at",
      "key",
      "module_id",
      "updated_at",
      "value",
    ]);
    // One row per (module, key): a module can never have two values for one key, enforced by the
    // database rather than by application care.
    expect(primaryKey.map((column) => column.column_name)).toEqual(["module_id", "key"]);
    expect(checks.map((check) => check.constraint_name)).toEqual([
      "ekklesia_core_module_configuration_key_check",
      "ekklesia_core_module_configuration_module_check",
      "ekklesia_core_module_configuration_value_check",
    ]);
    // Deliberately absent: there is no column that could hold secret material, and none that
    // records where a value came from. Secrets are deployment-supplied and never persisted.
    expect(columns.map((column) => column.column_name)).not.toContain("secret");
    expect(columns.map((column) => column.column_name)).not.toContain("encrypted");
  });

  it("reads an empty configuration from a freshly migrated database", async () => {
    const view = createValidatedPostgresPool(database.url, {
      connectionTimeoutMs: 10_000,
      operationTimeoutMs: 10_000,
    });
    close = view.close;
    store = createModuleConfigurationStore(createModuleConfigurationView(view.pool));

    expect(await store.readSettings()).toEqual({ records: [] });
  });

  it("persists values and reads them back over a completely new connection", async () => {
    await store.replace({
      moduleId: "announcements",
      values: [
        { key: "bucket", value: "slides" },
        { key: "slideSeconds", value: "12" },
      ],
    });

    const separate = createValidatedPostgresPool(database.url, {
      connectionTimeoutMs: 10_000,
      operationTimeoutMs: 10_000,
    });
    try {
      const reread = await createModuleConfigurationStore(
        createModuleConfigurationView(separate.pool),
      ).readSettings();
      expect(reread.records).toEqual([
        { key: "bucket", moduleId: "announcements", value: "slides" },
        { key: "slideSeconds", moduleId: "announcements", value: "12" },
      ]);
    } finally {
      await separate.close();
    }
  });

  it("replaces the whole document for one module, clearing keys the submission omits", async () => {
    await store.replace({
      moduleId: "announcements",
      values: [{ key: "bucket", value: "slides" }],
    });

    expect((await store.readSettings()).records).toEqual([
      { key: "bucket", moduleId: "announcements", value: "slides" },
    ]);
  });

  it("never touches another module's rows during a replace", async () => {
    await store.replace({ moduleId: "calendar", values: [{ key: "bucket", value: "events" }] });
    await store.replace({
      moduleId: "announcements",
      values: [{ key: "bucket", value: "renamed" }],
    });

    expect((await store.readSettings()).records).toEqual([
      { key: "bucket", moduleId: "announcements", value: "renamed" },
      { key: "bucket", moduleId: "calendar", value: "events" },
    ]);
  });

  it("clears a module's document entirely when given no values", async () => {
    await store.replace({ moduleId: "calendar", values: [] });

    expect(
      (await store.readSettings()).records.filter((record) => record.moduleId === "calendar"),
    ).toEqual([]);
  });

  it("treats a module id and a key as data, never as an SQL identifier", async () => {
    // The store validates identifiers before they reach PostgreSQL, so this is rejected by the
    // application. The row count afterwards proves nothing was executed either way.
    await expect(
      store.replace({
        moduleId: 'announcements"; drop table ekklesia_core_module_configuration; --',
        values: [{ key: "bucket", value: "x" }],
      }),
    ).rejects.toMatchObject({ code: "MODULE_CONFIGURATION_MODULE_ID_INVALID" });
    await expect(
      store.replace({
        moduleId: "announcements",
        values: [{ key: 'bucket"; drop table ekklesia_core_module_configuration; --', value: "x" }],
      }),
    ).rejects.toMatchObject({ code: "MODULE_CONFIGURATION_KEY_INVALID" });

    const tables = await safeQuery<{ count: string }>(
      admin,
      `select count(*)::text as count from information_schema.tables
        where table_name = 'ekklesia_core_module_configuration'`,
    );
    expect(tables[0]?.count).toBe("1");
  });

  it("rejects a duplicate key in one submission before reaching the database", async () => {
    await expect(
      store.replace({
        moduleId: "announcements",
        values: [
          { key: "bucket", value: "a" },
          { key: "bucket", value: "b" },
        ],
      }),
    ).rejects.toBeInstanceOf(ModuleConfigurationStoreError);
  });

  it("rejects an oversized value at the application boundary and at the database", async () => {
    await expect(
      store.replace({
        moduleId: "announcements",
        values: [{ key: "bucket", value: "x".repeat(2049) }],
      }),
    ).rejects.toMatchObject({ code: "MODULE_CONFIGURATION_VALUE_INVALID" });

    // Defense in depth: the same ceiling restated where the data lives, so no future caller can
    // store a value the resolver would then reject as invalid on every boot.
    await expect(
      safeQuery(
        admin,
        `insert into ekklesia_core_module_configuration (module_id, key, value)
         values ('announcements', 'oversized', repeat('x', 2049))`,
      ),
    ).rejects.toThrow();
  });

  it("never carries a configuration value in a store error", async () => {
    let captured: unknown;
    try {
      await store.replace({
        moduleId: "announcements",
        values: [{ key: "bucket", value: "a-value-nobody-should-see".repeat(200) }],
      });
    } catch (error) {
      captured = error;
    }

    const rendered = `${String(captured)} ${JSON.stringify(captured)}`;
    expect(rendered).not.toContain("a-value-nobody-should-see");
  });

  it("retains a value for a module that is no longer deployed, and resolution ignores it", async () => {
    await store.replace({
      moduleId: "announcements",
      values: [{ key: "bucket", value: "slides" }],
    });
    await store.replace({ moduleId: "retired", values: [{ key: "bucket", value: "old" }] });
    const settings = await store.readSettings();

    const resolved = resolveModuleConfigurationFor(
      manifestWith([{ key: "bucket", type: "string", required: true }]),
      { settings },
    );

    expect(resolved.configuration?.getString("bucket")).toBe("slides");
    // Retained rather than deleted: redeploying `retired` restores its value with no new write.
    expect(settings.records.some((record) => record.moduleId === "retired")).toBe(true);
  });

  it("drives real validation and defaulting from real stored rows", async () => {
    await store.replace({
      moduleId: "announcements",
      values: [
        { key: "bucket", value: "slides" },
        { key: "slideSeconds", value: "900" },
      ],
    });

    const manifest = manifestWith([
      { key: "bucket", type: "string", required: true },
      { key: "slideSeconds", type: "integer", default: 7, minimum: 1, maximum: 600 },
      { key: "pollIntervalSeconds", type: "integer", default: 30 },
    ]);
    const resolved = resolveModuleConfigurationFor(manifest, {
      settings: await store.readSettings(),
    });

    // 900 exceeds the module's own declared maximum: reported, never clamped and never silently
    // replaced by the default.
    expect(resolved.configuration).toBeUndefined();
    expect(resolved.issue).toEqual({ key: "slideSeconds", reason: "configuration_invalid" });

    await store.replace({
      moduleId: "announcements",
      values: [
        { key: "bucket", value: "slides" },
        { key: "slideSeconds", value: "12" },
      ],
    });
    const fixed = resolveModuleConfigurationFor(manifest, { settings: await store.readSettings() });
    expect(fixed.configuration?.getInteger("slideSeconds")).toBe(12);
    expect(fixed.configuration?.getInteger("pollIntervalSeconds")).toBe(30);

    await close();
  });
});