claude-code-action/src/entrypoints/prepare.ts

#!/usr/bin/env bun

/**
 * Prepare the Claude action by checking trigger conditions, verifying human actor,
 * and creating the initial tracking comment
 */

import * as core from "@actions/core";
import { setupGitHubToken } from "../github/token";
import { checkWritePermissions } from "../github/validation/permissions";
import { createOctokit } from "../github/api/client";
import { parseGitHubContext, isEntityContext } from "../github/context";
import { getMode } from "../modes/registry";
import { prepare } from "../prepare";

async function run() {
  try {
    // Parse GitHub context first to enable mode detection
    const context = parseGitHubContext();

    // Auto-detect mode based on context
    const mode = getMode(context);

    // Setup GitHub token
    const githubToken = await setupGitHubToken();
    const octokit = createOctokit(githubToken);

    // Step 3: Check write permissions (only for entity contexts)
    if (isEntityContext(context)) {
      const hasWritePermissions = await checkWritePermissions(
        octokit.rest,
        context,
      );
      if (!hasWritePermissions) {
        throw new Error(
          "Actor does not have write permissions to the repository",
        );
      }
    }

    // Check trigger conditions
    const containsTrigger = mode.shouldTrigger(context);

    // Set output for action.yml to check
    core.setOutput("contains_trigger", containsTrigger.toString());

    if (!containsTrigger) {
      console.log("No trigger found, skipping remaining steps");
      return;
    }

    // Step 5: Use the new modular prepare function
    const result = await prepare({
      context,
      octokit,
      mode,
      githubToken,
    });

    // MCP config is handled by individual modes (tag/agent) and included in their claude_args output

    // Step 6: Get system prompt from mode if available
    if (mode.getSystemPrompt) {
      const modeContext = mode.prepareContext(context, {
        commentId: result.commentId,
        baseBranch: result.branchInfo.baseBranch,
        claudeBranch: result.branchInfo.claudeBranch,
      });
      const systemPrompt = mode.getSystemPrompt(modeContext);
      if (systemPrompt) {
        core.exportVariable("APPEND_SYSTEM_PROMPT", systemPrompt);
      }
    }
  } catch (error) {
    const errorMessage = error instanceof Error ? error.message : String(error);
    core.setFailed(`Prepare step failed with error: ${errorMessage}`);
    // Also output the clean error message for the action to capture
    core.setOutput("prepare_error", errorMessage);
    process.exit(1);
  }
}

if (import.meta.main) {
  run();
}