feat: add continue/new support to chat frontends

frontends/continue_cmd.py

@@ -2,10 +2,12 @@
 Pure functions + one `install(cls)` monkey-patch entry. No side effects at import.
 """
 import ast, glob, json, os, re, time
-_LOG_GLOB = os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))),
-                         'temp', 'model_responses', 'model_responses_*.txt')
+_LOG_DIR = os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))),
+                        'temp', 'model_responses')
+_LOG_GLOB = os.path.join(_LOG_DIR, 'model_responses_*.txt')
 _BLOCK_RE = re.compile(r'^=== (Prompt|Response) ===.*?\n(.*?)(?=^=== (?:Prompt|Response) ===|\Z)',
                        re.DOTALL | re.MULTILINE)
+_SUMMARY_RE = re.compile(r'<summary>\s*(.*?)\s*</summary>', re.DOTALL)
 
 def _rel_time(mtime):
     d = int(time.time() - mtime)
@@ -38,6 +40,32 @@ def _first_user(pairs):
             if s and not s.startswith('###'): return s
     return ''
 
+
+def _last_summary(pairs):
+    for _, response_body in reversed(pairs):
+        try:
+            blocks = ast.literal_eval(response_body)
+        except Exception:
+            continue
+        if not isinstance(blocks, list):
+            continue
+        text_parts = []
+        for block in blocks:
+            if isinstance(block, dict) and block.get('type') == 'text':
+                text = block.get('text', '')
+                if isinstance(text, str) and text:
+                    text_parts.append(text)
+        match = _SUMMARY_RE.search('\n'.join(text_parts))
+        if match:
+            summary = match.group(1).strip()
+            if summary:
+                return summary
+    return ''
+
+
+def _preview_text(pairs):
+    return _last_summary(pairs) or _first_user(pairs)
+
 def _parse_native_history(pairs):
     history = []
     for p, r in pairs:
@@ -60,16 +88,82 @@ def list_sessions(exclude_pid=None):
     out = []
     for f in files:
         try:
-            content = open(f, encoding='utf-8', errors='replace').read()
+            with open(f, encoding='utf-8', errors='replace') as fh:
+                content = fh.read()
         except Exception: continue
         pairs = _pairs(content)
         if not pairs: continue
-        out.append((f, os.path.getmtime(f), _first_user(pairs), len(pairs)))
+        out.append((f, os.path.getmtime(f), _preview_text(pairs), len(pairs)))
     out.sort(key=lambda x: x[1], reverse=True)
     return out
 _MD_ESCAPE_RE = re.compile(r'([\\`*_\[\]])')
 def _escape_md(s): return _MD_ESCAPE_RE.sub(r'\\\1', s)
 
+
+def _agent_clients(agent):
+    clients = []
+    for client in getattr(agent, 'llmclients', []) or []:
+        if client not in clients:
+            clients.append(client)
+    current = getattr(agent, 'llmclient', None)
+    if current is not None and current not in clients:
+        clients.insert(0, current)
+    return clients
+
+
+def _replace_backend_history(agent, history):
+    backend = getattr(getattr(agent, 'llmclient', None), 'backend', None)
+    if backend is not None and hasattr(backend, 'history'):
+        backend.history = list(history or [])
+
+
+def _current_log_path(pid=None):
+    pid = os.getpid() if pid is None else pid
+    return os.path.join(_LOG_DIR, f'model_responses_{pid}.txt')
+
+
+def _snapshot_current_log(pid=None):
+    """Persist current PID log as a standalone recoverable snapshot, then clear it."""
+    path = _current_log_path(pid)
+    if not os.path.isfile(path):
+        return None
+    try:
+        with open(path, encoding='utf-8', errors='replace') as fh:
+            content = fh.read()
+    except Exception:
+        return None
+    if not _pairs(content):
+        return None
+    os.makedirs(_LOG_DIR, exist_ok=True)
+    pid = os.getpid() if pid is None else pid
+    stamp = time.strftime('%Y%m%d_%H%M%S')
+    snapshot = os.path.join(_LOG_DIR, f'model_responses_snapshot_{pid}_{stamp}_{time.time_ns() % 1_000_000_000:09d}.txt')
+    with open(snapshot, 'w', encoding='utf-8', errors='replace') as fh:
+        fh.write(content)
+    with open(path, 'w', encoding='utf-8', errors='replace'):
+        pass
+    return snapshot
+
+
+def reset_conversation(agent, message='🆕 已开启新对话，当前上下文已清空'):
+    """Abort current work and clear all known frontend-visible conversation state."""
+    try:
+        agent.abort()
+    except Exception:
+        pass
+    _snapshot_current_log()
+    if hasattr(agent, 'history'):
+        agent.history = []
+    for client in _agent_clients(agent):
+        backend = getattr(client, 'backend', None)
+        if backend is not None and hasattr(backend, 'history'):
+            backend.history = []
+        if hasattr(client, 'last_tools'):
+            client.last_tools = ''
+    if hasattr(agent, 'handler'):
+        agent.handler = None
+    return message
+
 def format_list(sessions, limit=20):
     if not sessions: return '❌ 没有可恢复的历史会话'
     lines = ['**可恢复会话**（输入 `/continue N` 恢复第 N 个）：', '']
@@ -80,7 +174,9 @@ def format_list(sessions, limit=20):
 
 def restore(agent, path):
     """Restore session at path. Returns (msg, is_full)."""
-    try: content = open(path, encoding='utf-8', errors='replace').read()
+    try:
+        with open(path, encoding='utf-8', errors='replace') as fh:
+            content = fh.read()
     except Exception as e: return f'❌ 读取失败: {e}', False
     pairs = _pairs(content)
     if not pairs: return f'❌ {os.path.basename(path)} 为空或格式不符', False
@@ -88,7 +184,7 @@ def restore(agent, path):
     name = os.path.basename(path)
     if history is not None:
         agent.abort()
-        agent.llmclient.backend.history = history
+        _replace_backend_history(agent, history)
         return f'✅ 已恢复 {len(pairs)} 轮完整对话（{name}）\n(已写入 backend.history，可直接继续)', True
     from chatapp_common import _restore_native_history, _restore_text_pairs
     summary = _restore_text_pairs(content) or _restore_native_history(content)
@@ -111,10 +207,31 @@ def handle(agent, query, display_queue):
         if not (0 <= idx < len(sessions)):
             display_queue.put({'done': f'❌ 索引越界（有效范围 1-{len(sessions)}）', 'source': 'system'})
             return None
+        reset_conversation(agent, message=None)
         msg, _ = restore(agent, sessions[idx][0])
         display_queue.put({'done': msg, 'source': 'system'})
         return None
     return query
+
+
+def handle_frontend_command(agent, query, exclude_pid=None):
+    """Frontend-friendly /continue entry that returns text directly."""
+    s = (query or '').strip()
+    exclude_pid = os.getpid() if exclude_pid is None else exclude_pid
+    if s == '/continue':
+        return format_list(list_sessions(exclude_pid=exclude_pid))
+    m = re.match(r'/continue\s+(\d+)\s*$', s)
+    if not m:
+        return '用法: /continue 或 /continue N'
+    sessions = list_sessions(exclude_pid=exclude_pid)
+    idx = int(m.group(1)) - 1
+    if not (0 <= idx < len(sessions)):
+        return f'❌ 索引越界（有效范围 1-{len(sessions)}）'
+    reset_conversation(agent, message=None)
+    msg, _ = restore(agent, sessions[idx][0])
+    return msg
+
+
 def install(cls):
     """Wrap cls._handle_slash_cmd so /continue is handled before original dispatch."""
     orig = cls._handle_slash_cmd