/**
 * Agent 交互模块
 */
import { App } from './state.js';
import { escapeHtml } from './utils.js';
import { addChatMessage, showStatus } from './chat.js';
import { createSSEConnection, handleDoneResult } from './sse.js';

// ================================================================
// Agent 事件处理
// ================================================================

/**
 * 处理 Agent SSE 事件
 *
 * @param {Object} msg - SSE 传来的 agent 事件对象
 */
export function handleAgentEvent(msg) {
  switch (msg.type) {
    case 'agent_state_change':
      _handleAgentStateChange(msg);
      break;
    case 'agent_request_supplement':
      _handleAgentRequestSupplement(msg);
      break;
    case 'agent_ready':
      _handleAgentReady(msg);
      break;
    case 'agent_error':
      _handleAgentError(msg);
      break;
    case 'agent_supplement_received':
      _handleSupplementReceived(msg);
      break;
    case 'agent_force_submit':
      _handleForceSubmit(msg);
      break;
    case 'agent_max_rounds':
      _handleAgentError(msg);
      break;
    case 'agent_extract_status':
      _handleAgentStateChange(msg);
      break;
  }
}

/**
 * 状态变更通知 — 使用瞬态消息，状态变化时更新而非追加
 */
function _handleAgentStateChange(msg) {
  const stateLabels = {
    'extracting': '正在分析文件...',
    'validating': '正在校验信息完整性...',
    'awaiting_supplement': '等待补充材料',
    'ready': '信息完整，可以提交',
    'submitting': '正在提交...',
  };

  const label = stateLabels[msg.state] || msg.message || '处理中...';

  if (msg.state === 'ready') {
    showStatus(label, 'done');
  } else {
    showStatus(label);
  }
}

/**
 * 请求补充材料 — 将 suggestion 以消息气泡形式单独展示
 */
export function _handleAgentRequestSupplement(msg) {
  const suggestion = msg.suggestion || '请补充上传相关材料';
  showStatus('信息不完整，请补充材料');
  addChatMessage(suggestion, 'system');
}

/**
 * 信息完整 — 在消息气泡中提醒用户，最终结果由 done 事件处理
 */
function _handleAgentReady(msg) {
  addChatMessage(msg.message || '信息完整，正在提交到财务系统', 'done');
}

/**
 * Agent 错误
 */
function _handleAgentError(msg) {
  addChatMessage(msg.message || 'Agent 处理出错', 'error');
  App.isProcessing = false;
  App.processState = 'done';
}

/**
 * 收到补充文件
 */
function _handleSupplementReceived(msg) {
  const fileNames = (msg.files || []).join('、');
  addChatMessage(`已收到补充文件：${fileNames}`, 'done');
}

/**
 * 强制提交
 */
function _handleForceSubmit(msg) {
  showStatus('已跳过校验，开始提交到财务系统');
}

// ================================================================
// Agent 请求面板
// ================================================================

/**
 * 显示 Agent 请求补充材料的 UI
 */
export function showAgentRequest(data) {
  const existing = document.getElementById('agent-request-panel');
  if (existing) existing.remove();

  const chatMessages = document.getElementById('chat-messages');
  if (!chatMessages) return;

  const panel = document.createElement('div');
  panel.id = 'agent-request-panel';
  panel.className = 'agent-request-panel';

  let materialsHtml = '';
  if (data.missing_materials && data.missing_materials.length > 0) {
    materialsHtml = `
      <div class="agent-request-materials">
        <strong>需要补充：</strong>
        ${data.missing_materials.map(m => `<span class="material-tag">${escapeHtml(m)}</span>`).join(' ')}
      </div>
    `;
  }

  panel.innerHTML = `
    <div class="agent-request-header">
      <span class="agent-request-icon"><img src="/static/icon/file.svg" alt=""></span>
      <span>第 ${data.round || 1} 轮分析 - 信息不完整</span>
    </div>
    ${materialsHtml}
    <div class="agent-request-actions">
      <button class="btn btn-sm btn-primary" onclick="document.getElementById('file-input').click()">
        上传补充材料
      </button>
      <button class="btn btn-sm btn-outline-secondary" onclick="handleForceSubmit()">
        直接提交
      </button>
    </div>
  `;

  chatMessages.appendChild(panel);
  chatMessages.scrollTop = chatMessages.scrollHeight;
}

/**
 * 移除 Agent 请求面板
 */
export function hideAgentRequest() {
  const panel = document.getElementById('agent-request-panel');
  if (panel) panel.remove();
}

// ================================================================
// 用户文字补充
// ================================================================

/**
 * 处理用户通过输入框补充的文字信息
 *
 * @param {string} text - 用户输入的文字
 */
export async function handleUserSupplement(text) {
  if (!App.sessionId) return;

  try {
    showStatus('正在解析补充信息...');

    const response = await fetch(`/api/agent/user-supplement/${App.sessionId}`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ text: text }),
    });

    const result = await response.json();

    if (result.status === 'started') {
      showStatus('补充信息已收到，正在重新分析...');
      App.isProcessing = true;

      createSSEConnection(App.sessionId, {
        onDone: (result) => {
          handleDoneResult(result);
        },
        handleFileProgress: false,
        handleLLMStream: false,
      });
    } else if (result.error) {
      addChatMessage(`处理失败：${result.error}`, 'error');
    }
  } catch (e) {
    addChatMessage(`请求失败：${e.message}`, 'error');
  }
}

// ================================================================
// 用户输入处理
// ================================================================

/**
 * 处理强制提交
 */
export async function handleForceSubmit() {
  if (!App.sessionId) {
    addChatMessage('请先上传文件并处理', 'error');
    return;
  }

  if (App.agentEventSource) {
    App.agentEventSource.close();
    App.agentEventSource = null;
  }

  App.forceSubmitting = true;

  try {
    showStatus('正在跳过校验并提交...');
    hideAgentRequest();

    const response = await fetch(`/api/agent/force-submit/${App.sessionId}`, {
      method: 'POST',
    });

    const result = await response.json();

    if (result.status === 'started') {
      showStatus('已跳过校验，开始提交到财务系统');
      App.isProcessing = true;
      App.processState = 'submitting';

      createSSEConnection(App.sessionId, {
        onDone: (result) => {
          handleDoneResult(result);
        },
        handleFileProgress: false,
        handleLLMStream: false,
      });
    }
  } catch (e) {
    App.forceSubmitting = false;
    addChatMessage(`请求失败：${e.message}`, 'error');
  }
}

// ================================================================
// 补充文件处理
// ================================================================

/**
 * 处理补充文件上传完成后的重新分析
 *
 * @param {Array<string>} filenames - 新上传的文件名列表
 */
export async function handleSupplementUpload(filenames) {
  if (!App.sessionId) return;

  try {
    showStatus('收到补充文件，正在重新分析...');
    hideAgentRequest();

    const response = await fetch(`/api/agent/supplement/${App.sessionId}`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ files: filenames }),
    });

    const result = await response.json();

    if (result.status === 'started') {
      App.isProcessing = true;

      createSSEConnection(App.sessionId, {
        onDone: (result) => {
          handleDoneResult(result);
        },
      });
    }
  } catch (e) {
    addChatMessage(`请求失败：${e.message}`, 'error');
  }
}