import { writeFile, unlink } from 'fs/promises';
import { join } from 'path';
import { tmpdir } from 'os';
import { randomUUID } from 'crypto';
import { fileURLToPath } from 'url';
import { runClaudeTurn } from '../claude_cli.js';

// Absolute path to the MCP stdio server the claude child spawns.
const STDIO_PATH = fileURLToPath(new URL('../../mcp/companion-stdio.js', import.meta.url));

/**
 * Shared agent turn-runner: builds the per-turn MCP config (selecting the tool
 * registry + injecting agent/space/view), runs one claude turn, cleans up.
 * SSE/persistence stay in the route. Returns runClaudeTurn's result.
 */
export async function runAgentTurn({
  agent, persona, registryName, toolNames, spaceId = null, view = null,
  sessionId, resume = false, userText, claudeExe = 'claude', home, onEvent, extraEnv = {}
}) {
  const agentActor = { kind: 'agent', id: agent.id, capabilities: agent.capabilities, scopes: agent.scopes };
  const mcpConfigPath = join(tmpdir(), `void-mcp-${randomUUID()}.json`);
  const mcpConfig = {
    mcpServers: {
      void: {
        command: process.execPath,
        args: [STDIO_PATH],
        env: {
          VOID_TOOL_REGISTRY: registryName || '',
          VOID_SPACE_ID: spaceId || '',
          VOID_AGENT_JSON: JSON.stringify(agentActor),
          VOID_VIEW_JSON: view ? JSON.stringify(view) : '',
          DATABASE_URL: process.env.DATABASE_URL || '',
          OLLAMA_URL: process.env.OLLAMA_URL || '',
          ...extraEnv
        }
      }
    }
  };
  await writeFile(mcpConfigPath, JSON.stringify(mcpConfig));
  try {
    return await runClaudeTurn({
      sessionId, resume, systemPrompt: persona, userText,
      mcpConfigPath, tools: toolNames, allowedTools: toolNames,
      claudeExe, home, onEvent
    });
  } finally {
    unlink(mcpConfigPath).catch(() => {});
  }
}