/**
 * InstallToolsNudge — mid-run reminder when the user asked to install
 * dependencies but no package-manager install exec has run yet.
 *
 * Soft: max 1 fire. Pairs with evaluateInventedInstallCompletionGate.
 */

export const INSTALL_TOOLS_NUDGE_MAX_ATTEMPTS = 1;

const INSTALL_USER_RE =
  /(?:\bnpm\s+install\b|\bpnpm\s+i(?:nstall)?\b|\byarn\s+install\b|\bbun\s+install\b|install (?:the )?dependencies|install deps|装依赖|安装依赖)/iu;

const EXEC_TOOLS = new Set(['exec', 'exec_background']);

export interface InstallToolsNudgeRequest {
  userText: string;
  toolCallsByName: Record<string, number>;
  messages?: Array<{ role?: string; content?: unknown }>;
  totalToolCalls: number;
  attempts: number;
}

export type InstallToolsNudgeResult =
  | { fire: false }
  | { fire: true; correction: string };

function collectExecCommands(
  messages: Array<{ role?: string; content?: unknown }> | undefined,
): string[] {
  if (!messages?.length) return [];
  const out: string[] = [];
  for (const m of messages) {
    if (!m || m.role !== 'assistant' || !Array.isArray(m.content)) continue;
    for (const block of m.content) {
      const b = block as { type?: string; name?: string; input?: unknown };
      if (b?.type !== 'tool_use' || !b.name || !EXEC_TOOLS.has(b.name)) continue;
      const input = b.input;
      if (!input || typeof input !== 'object') continue;
      const o = input as Record<string, unknown>;
      for (const key of ['command', 'cmd', 'input'] as const) {
        if (typeof o[key] === 'string' && String(o[key]).trim()) {
          out.push(String(o[key]));
          break;
        }
      }
    }
  }
  return out;
}

function sawInstallExec(
  messages: Array<{ role?: string; content?: unknown }> | undefined,
): boolean {
  for (const cmd of collectExecCommands(messages)) {
    if (
      /\b(?:npm|pnpm|yarn|bun)\s+(?:i|install|ci|add)\b/i.test(cmd) ||
      /\bpip(?:3)?\s+install\b/i.test(cmd)
    ) {
      return true;
    }
  }
  return false;
}

export function evaluateInstallToolsNudge(
  request: InstallToolsNudgeRequest,
): InstallToolsNudgeResult {
  if (request.attempts >= INSTALL_TOOLS_NUDGE_MAX_ATTEMPTS) return { fire: false };
  if (request.totalToolCalls < 1) return { fire: false };

  const user = (request.userText || '').trim();
  if (!user || !INSTALL_USER_RE.test(user)) return { fire: false };

  if (sawInstallExec(request.messages)) return { fire: false };

  return {
    fire: true,
    correction:
      '[System] The user asked to install dependencies, and tools have already run without an install command ' +
      '(`npm`/`pnpm`/`yarn`/`bun` install/ci/add, or `pip install`). ' +
      'Run the real package-manager install via `exec` and report the output, or clearly say install was skipped. ' +
      'Do not invent install success.',
  };
}