ECC/scripts/lib/install-targets/copilot-project.js

const path = require('path');

const {
  createInstallTargetAdapter,
  createManagedOperation,
  createManagedScaffoldOperation,
  normalizeRelativePath,
} = require('./helpers');

// GitHub Copilot CLI discovers skills from `.github/skills/` and custom agents
// from `.github/agents/`. Those two directories are the entire supported
// surface for this target: ECC's hooks target Claude Code's event model, and
// commands rely on slash-command argument substitution Copilot does not
// provide, so neither is installed here.
const SUPPORTED_SOURCE_PREFIXES = ['agents', 'skills'];

function supportsCopilotSourcePath(sourceRelativePath) {
  const normalizedPath = normalizeRelativePath(sourceRelativePath);
  return SUPPORTED_SOURCE_PREFIXES.some(prefix => (
    normalizedPath === prefix || normalizedPath.startsWith(`${prefix}/`)
  ));
}

function stripPrefix(normalizedPath, prefix) {
  return normalizedPath === prefix ? '' : normalizedPath.slice(`${prefix}/`.length);
}

module.exports = createInstallTargetAdapter({
  id: 'copilot-project',
  target: 'copilot',
  kind: 'project',
  rootSegments: ['.github'],
  installStatePathSegments: ['ecc-install-state.json'],
  supportsModule(module) {
    // Selection gating stays permissive so modules that only act as dependency
    // anchors (rules-core, commands-core, platform-configs) still resolve.
    // planOperations() is what narrows the install to agents and skills, so an
    // unsupported path contributes zero operations rather than skipping the
    // module and every module that depends on it.
    const paths = Array.isArray(module && module.paths) ? module.paths : [];
    return paths.length > 0;
  },
  planOperations(input, adapter) {
    const modules = Array.isArray(input.modules)
      ? input.modules
      : (input.module ? [input.module] : []);
    const {
      repoRoot,
      projectRoot,
      homeDir,
    } = input;
    const targetRoot = adapter.resolveRoot({ repoRoot, projectRoot, homeDir });

    return modules.flatMap(module => {
      const paths = Array.isArray(module.paths) ? module.paths : [];
      return paths
        .filter(supportsCopilotSourcePath)
        .flatMap(sourceRelativePath => {
          const normalizedSourcePath = normalizeRelativePath(sourceRelativePath);

          if (
            normalizedSourcePath === 'agents'
            || normalizedSourcePath.startsWith('agents/')
          ) {
            return [
              createManagedOperation({
                moduleId: module.id,
                sourceRelativePath: normalizedSourcePath,
                destinationPath: path.join(
                  targetRoot,
                  'agents',
                  stripPrefix(normalizedSourcePath, 'agents')
                ),
                strategy: 'preserve-relative-path',
                contentTransform: 'copilot-agent-frontmatter',
              }),
            ];
          }

          if (
            normalizedSourcePath === 'skills'
            || normalizedSourcePath.startsWith('skills/')
          ) {
            return [
              createManagedScaffoldOperation(
                module.id,
                normalizedSourcePath,
                path.join(targetRoot, 'skills', stripPrefix(normalizedSourcePath, 'skills')),
                'preserve-relative-path'
              ),
            ];
          }

          return [];
        });
    });
  },
});