/**
 * mission_scaffold tool
 * 
 * First-time setup tool - copies bundled worker/auditor agents and skills
 * into project .pi dirs and creates mission-control directory structure.
 * 
 * This is a command-only tool (not exposed to agents).
 */

import * as path from "path";
import * as fs from "fs";
import { fileURLToPath } from "url";
import {
  getProjectRoot,
  getMissionControlDir,
  getMemoryDir,
  getRunsDir,
  ensureDir,
  copyDir,
  fileExists,
  writeJson,
  defaultState,
  isScaffolded
} from "../state.js";

export interface ScaffoldResult {
  success: boolean;
  message: string;
  created: string[];
  skipped: string[];
  errors: string[];
}

const packageRoot = path.join(path.dirname(fileURLToPath(import.meta.url)), "..", "..");

/**
 * Get the bundled agents directory path (within the npm package)
 */
function getBundledAgentsDir(): string {
  return path.join(packageRoot, "agents");
}

/**
 * Get the bundled skills directory path (within the npm package)
 */
function getBundledSkillsDir(): string {
  return path.join(packageRoot, "skills");
}

/**
 * Get the bundled templates directory path (within the npm package)
 */
function getBundledTemplatesDir(): string {
  return path.join(packageRoot, "templates");
}

/**
 * Get target paths in the project
 */
function getTargetPaths() {
  const projectRoot = getProjectRoot();
  return {
    agents: path.join(projectRoot, ".pi", "agents"),
    skills: path.join(projectRoot, ".pi", "skills"),
    missionControl: getMissionControlDir(),
    memory: getMemoryDir(),
    runs: getRunsDir()
  };
}

/**
 * Scaffold the mission-control environment
 * 
 * Copies bundled worker/auditor agents and skills to project .pi dirs and creates
 * the mission-control directory structure. Non-destructive - 
 * skips existing files rather than overwriting.
 */
export function missionScaffold(): ScaffoldResult {
  const result: ScaffoldResult = {
    success: true,
    message: "",
    created: [],
    skipped: [],
    errors: []
  };

  try {
    const bundledDirs = {
      agents: getBundledAgentsDir(),
      skills: getBundledSkillsDir(),
      templates: getBundledTemplatesDir()
    };

    const targetPaths = getTargetPaths();

    // Verify bundled directories exist
    for (const [name, dirPath] of Object.entries(bundledDirs)) {
      if (!fileExists(dirPath)) {
        result.errors.push(`Bundled ${name} directory not found: ${dirPath}`);
      }
    }

    if (result.errors.length > 0) {
      result.success = false;
      result.message = "Scaffolding failed: bundled resources not found";
      return result;
    }

    // Create base directory structure
    ensureDir(targetPaths.missionControl);
    ensureDir(targetPaths.memory);
    ensureDir(targetPaths.runs);
    result.created.push(".pi/mission-control/");
    result.created.push(".pi/mission-control/memory/");
    result.created.push(".pi/mission-control/runs/");

    // Create state.json if it doesn't exist
    const statePath = path.join(targetPaths.missionControl, "state.json");
    if (!fileExists(statePath)) {
      writeJson(statePath, defaultState);
      result.created.push(".pi/mission-control/state.json");
    } else {
      result.skipped.push(".pi/mission-control/state.json (already exists)");
    }

    // Copy worker/auditor agents (skip existing files)
    const agentsCopied = copyDir(bundledDirs.agents, targetPaths.agents, true);
    if (agentsCopied > 0) {
      result.created.push(`.pi/agents/ (${agentsCopied} files copied)`);
    } else {
      result.skipped.push(".pi/agents/ (all files already exist)");
    }

    // Copy skills (skip existing files)
    const skillsCopied = copyDir(bundledDirs.skills, targetPaths.skills, true);
    if (skillsCopied > 0) {
      result.created.push(`.pi/skills/ (${skillsCopied} files copied)`);
    } else {
      result.skipped.push(".pi/skills/ (all files already exist)");
    }

    // Create long_term.md if it doesn't exist
    const longTermPath = path.join(targetPaths.memory, "long_term.md");
    if (!fileExists(longTermPath)) {
      fs.writeFileSync(
        longTermPath,
        "# Long-term Memory\n\nDistilled knowledge from past missions.\n\n## Repo Conventions\n\n## Tooling Quirks\n\n## Architecture Decisions\n\n## Common Failures\n\n## Performance Notes\n",
        "utf-8"
      );
      result.created.push(".pi/mission-control/memory/long_term.md");
    } else {
      result.skipped.push(".pi/mission-control/memory/long_term.md (already exists)");
    }

    result.success = true;
    result.message = "Mission Control scaffolding complete";

  } catch (error) {
    result.success = false;
    result.message = `Scaffolding error: ${error instanceof Error ? error.message : String(error)}`;
    result.errors.push(String(error));
  }

  return result;
}