#!/usr/bin/env node
/**
 * Catalogue-vs-code drift gate per
 * [ADR-0025 §"Confirmation"](../docs/decisions/0025-authorization-model-privileges-roles-scopes.md).
 *
 * Asserts that every string literal passed to the authorization
 * decorators in the codebase belongs to the closed catalogue
 * declared in `libs/shared/auth/src/lib/authorization.types.ts`:
 *
 *   - `@RequirePrivilege('Portal.X', …)` → every arg ∈ PRIVILEGES
 *   - `@RequireRole('rh', …)`            → every arg ∈ FUNCTIONAL_ROLES
 *
 * The TypeScript type system enforces the same constraint at
 * compile time — the decorator signatures are typed against the
 * `Privilege` / `FunctionalRole` literal unions — so the gate is
 * defence-in-depth against escape hatches:
 *
 *   - explicit `as Privilege` casts (`'Portal.Foo' as Privilege`),
 *   - indirection through a `string`-typed local
 *     (`const slug = 'rh'; @RequireRole(slug)` — non-literal
 *     args are skipped here, but the gate at least catches the
 *     literal misspellings),
 *   - and the rarer case where a developer hand-edits the
 *     catalogue type union without updating the runtime constant.
 *
 * Implementation: the script parses the catalogue file and every
 * `.ts` file under `apps/` and `libs/` with the TypeScript compiler
 * API. For each `CallExpression` whose callee identifier matches
 * one of the decorator names, every string-literal argument is
 * checked against the catalogue. Non-literal arguments are
 * skipped silently; the gate is best-effort for those, but they
 * are caught by the TypeScript signature anyway.
 *
 * Exit code: 0 if no drift, 1 with a grouped report if drift is
 * found. The script does not consume any env vars; running it
 * directly (`node scripts/check-catalogue-drift.mjs`) and via
 * `pnpm ci:catalogue-drift` are equivalent.
 */

import { readFileSync, readdirSync, statSync } from 'node:fs';
import { dirname, join, relative, resolve } from 'node:path';
import { fileURLToPath } from 'node:url';
import ts from 'typescript';

const __filename = fileURLToPath(import.meta.url);
const __dirname = dirname(__filename);
const WORKSPACE_ROOT = resolve(__dirname, '..');

const CATALOGUE_PATH = join(WORKSPACE_ROOT, 'libs/shared/auth/src/lib/authorization.types.ts');

/**
 * Decorator name → catalogue array name. Adding a third decorator
 * (per ADR-0025's anticipated growth) is one line here plus the
 * matching test fixture.
 */
const DECORATOR_TO_CATALOGUE = {
  RequirePrivilege: 'PRIVILEGES',
  RequireRole: 'FUNCTIONAL_ROLES',
};

/**
 * Folders to skip when walking the workspace. Stays small on
 * purpose: every other path under `apps/` and `libs/` is fair
 * game for catalogue references, including specs (the persona
 * matrix in `auth-guards.persona-matrix.spec.ts` is a deliberate
 * usage and must stay in sync).
 */
const SKIPPED_DIRS = new Set([
  'node_modules',
  'dist',
  'coverage',
  '.nx',
  '.angular',
  '__screenshots__',
]);

/**
 * Files / subpaths to skip outright. The generated gRPC stubs
 * under `apps/portal-bff/src/grpc/gen/` carry their own
 * `roles[]` field that has nothing to do with the ADR-0025
 * functional-role catalogue — skipping the whole dir keeps the
 * scanner focused on hand-written code.
 */
const SKIPPED_SUBPATHS = ['apps/portal-bff/src/grpc/gen'];

/**
 * Parse `authorization.types.ts` and extract the catalogue
 * arrays as `Set<string>` keyed on the constant's name.
 * Returns `{ PRIVILEGES: Set, FUNCTIONAL_ROLES: Set }`.
 *
 * Exported for the spec — keeps the parser logic testable without
 * spawning the CLI.
 */
export function extractCatalogues(sourceFilePath = CATALOGUE_PATH) {
  const text = readFileSync(sourceFilePath, 'utf8');
  const sourceFile = ts.createSourceFile(sourceFilePath, text, ts.ScriptTarget.Latest, true);
  const out = {};

  for (const stmt of sourceFile.statements) {
    if (!ts.isVariableStatement(stmt)) continue;
    for (const decl of stmt.declarationList.declarations) {
      if (!ts.isIdentifier(decl.name) || !decl.initializer) continue;
      const name = decl.name.text;
      if (!Object.values(DECORATOR_TO_CATALOGUE).includes(name)) continue;

      // Catalogues are declared as `[...] as const`; strip the
      // type assertion to reach the array literal.
      let init = decl.initializer;
      if (ts.isAsExpression(init)) init = init.expression;
      if (!ts.isArrayLiteralExpression(init)) continue;

      const values = new Set();
      for (const el of init.elements) {
        if (ts.isStringLiteral(el) || ts.isNoSubstitutionTemplateLiteral(el)) {
          values.add(el.text);
        }
      }
      out[name] = values;
    }
  }

  for (const expected of Object.values(DECORATOR_TO_CATALOGUE)) {
    if (!out[expected]) {
      throw new Error(
        `Failed to extract catalogue "${expected}" from ${sourceFilePath} — ` +
          `the script expected a top-level "export const ${expected} = [...] as const" declaration.`,
      );
    }
  }

  return out;
}

/**
 * Walk `dir` recursively and yield every `.ts` file path
 * (excluding declaration files and the dirs listed in
 * SKIPPED_DIRS / SKIPPED_SUBPATHS).
 */
function* walkTsFiles(dir, rootForRelative) {
  let entries;
  try {
    entries = readdirSync(dir);
  } catch {
    return;
  }
  for (const entry of entries) {
    if (SKIPPED_DIRS.has(entry) || entry.startsWith('.')) continue;
    const full = join(dir, entry);
    const rel = relative(rootForRelative, full).replaceAll('\\', '/');
    if (SKIPPED_SUBPATHS.some((skip) => rel === skip || rel.startsWith(skip + '/'))) {
      continue;
    }
    let st;
    try {
      st = statSync(full);
    } catch {
      continue;
    }
    if (st.isDirectory()) {
      yield* walkTsFiles(full, rootForRelative);
    } else if (entry.endsWith('.ts') && !entry.endsWith('.d.ts')) {
      yield full;
    }
  }
}

/**
 * Find every catalogue-violation in a single source file.
 * Returns an array of `{ file, line, column, callee, value,
 * catalogue }` records. Exported for the spec.
 */
export function findViolationsInFile(filePath, catalogues, sourceText) {
  const text = sourceText ?? readFileSync(filePath, 'utf8');
  const sourceFile = ts.createSourceFile(filePath, text, ts.ScriptTarget.Latest, true);
  const violations = [];

  function visit(node) {
    if (ts.isCallExpression(node) && ts.isIdentifier(node.expression)) {
      const callee = node.expression.text;
      const catalogueName = DECORATOR_TO_CATALOGUE[callee];
      if (catalogueName) {
        const valid = catalogues[catalogueName];
        for (const arg of node.arguments) {
          if (ts.isStringLiteral(arg) || ts.isNoSubstitutionTemplateLiteral(arg)) {
            if (!valid.has(arg.text)) {
              const { line, character } = sourceFile.getLineAndCharacterOfPosition(arg.getStart());
              violations.push({
                file: filePath,
                line: line + 1,
                column: character + 1,
                callee,
                value: arg.text,
                catalogue: catalogueName,
              });
            }
          }
        }
      }
    }
    ts.forEachChild(node, visit);
  }

  visit(sourceFile);
  return violations;
}

/**
 * Top-level scan: walk `apps/` and `libs/`, accumulate
 * violations, return them all. Pure (no I/O outside the file
 * reads it does itself). Exported for the spec.
 */
export function scanWorkspace(workspaceRoot = WORKSPACE_ROOT) {
  const catalogues = extractCatalogues(
    join(workspaceRoot, 'libs/shared/auth/src/lib/authorization.types.ts'),
  );
  const out = [];
  for (const dirName of ['apps', 'libs']) {
    const dir = join(workspaceRoot, dirName);
    for (const file of walkTsFiles(dir, workspaceRoot)) {
      out.push(...findViolationsInFile(file, catalogues));
    }
  }
  return { violations: out, catalogues };
}

function main() {
  const { violations, catalogues } = scanWorkspace();

  if (violations.length === 0) {
    const privCount = catalogues.PRIVILEGES.size;
    const roleCount = catalogues.FUNCTIONAL_ROLES.size;
    console.log(
      `catalogue-drift: clean (catalogues: ${privCount} privileges, ${roleCount} roles).`,
    );
    process.exit(0);
  }

  console.error('catalogue-drift: violations found');
  console.error('');
  // Group by file for a readable report. Within a file, sort by
  // line so the output mirrors the editor's view.
  const byFile = new Map();
  for (const v of violations) {
    if (!byFile.has(v.file)) byFile.set(v.file, []);
    byFile.get(v.file).push(v);
  }
  for (const [file, list] of byFile) {
    list.sort((a, b) => a.line - b.line || a.column - b.column);
    const rel = relative(WORKSPACE_ROOT, file).replaceAll('\\', '/');
    console.error(`  ${rel}`);
    for (const v of list) {
      console.error(
        `    ${v.line}:${v.column}  @${v.callee}('${v.value}') — not in ${v.catalogue}`,
      );
    }
  }
  console.error('');
  console.error(
    `Catalogues are closed in v1 per ADR-0025. To add a value, amend ` +
      `the ADR and the corresponding constant in ` +
      `libs/shared/auth/src/lib/authorization.types.ts.`,
  );
  process.exit(1);
}

// Only run main() when invoked as a CLI (not when imported by the
// spec).
const isMain =
  import.meta.url === `file://${process.argv[1]}` ||
  import.meta.url === `file://${resolve(process.argv[1])}`;
if (isMain) {
  main();
}
