Add Brave web search support

app/config.py

@@ -60,6 +60,24 @@ class AIPromptConfig:
     user_template: str | None = None
 
 
+@dataclass(slots=True)
+class AIWebSearchConfig:
+    enabled: bool = True
+    api_key: str | None = None
+    endpoint: str = "https://api.search.brave.com/res/v1/web/search"
+    count: int = 5
+    country: str = "US"
+    search_lang: str = "en"
+    ui_lang: str = "en-US"
+    safesearch: str = "moderate"
+    timeout: float = 10.0
+    extra_snippets: bool = False
+
+    @property
+    def available(self) -> bool:
+        return self.enabled and bool(self.api_key)
+
+
 @dataclass(slots=True)
 class AIConfig:
     default_model: str
@@ -69,6 +87,7 @@ class AIConfig:
     models: dict[str, AIModelConfig] = field(default_factory=dict)
     workspace_dir: Path = field(default_factory=lambda: Path("workspace"))
     tool_max_rounds: int = 10
+    web_search: AIWebSearchConfig = field(default_factory=AIWebSearchConfig)
 
 
 @dataclass(slots=True)
@@ -127,6 +146,20 @@ def _parse_float(value: Any, *, field_name: str) -> float:
         raise ValueError(f"{field_name} must be a number") from exc
 
 
+def _parse_bool(value: Any, *, field_name: str) -> bool:
+    if isinstance(value, bool):
+        return value
+    if isinstance(value, str):
+        normalized = value.strip().lower()
+        if normalized in {"1", "true", "yes", "on"}:
+            return True
+        if normalized in {"0", "false", "no", "off"}:
+            return False
+    if isinstance(value, int):
+        return bool(value)
+    raise ValueError(f"{field_name} must be a boolean")
+
+
 def _parse_mapping(value: Any, *, field_name: str) -> dict[str, Any]:
     if value is None:
         return {}
@@ -135,6 +168,69 @@ def _parse_mapping(value: Any, *, field_name: str) -> dict[str, Any]:
     return value
 
 
+def _parse_web_search_config(raw_ai: dict[str, Any]) -> AIWebSearchConfig:
+    raw = _parse_mapping(raw_ai.get("web_search"), field_name="ai.web_search")
+
+    enabled = _parse_bool(raw.get("enabled", True), field_name="ai.web_search.enabled")
+    api_key = str(raw.get("api_key") or "").strip() or None
+    endpoint = str(
+        raw.get("endpoint") or "https://api.search.brave.com/res/v1/web/search"
+    ).strip()
+    if not endpoint:
+        raise ValueError("ai.web_search.endpoint is required")
+
+    count = _parse_int(raw.get("count", 5), field_name="ai.web_search.count")
+    count = min(max(count, 1), 20)
+
+    country = str(raw.get("country", "US") or "US").strip().upper()
+    search_lang = str(raw.get("search_lang", "en") or "en").strip().lower()
+    ui_lang = str(raw.get("ui_lang", "en-US") or "en-US").strip()
+    safesearch = str(raw.get("safesearch", "moderate") or "moderate").strip().lower()
+    if safesearch not in {"off", "moderate", "strict"}:
+        raise ValueError("ai.web_search.safesearch must be one of: off, moderate, strict")
+
+    timeout = _parse_float(raw.get("timeout", 10.0), field_name="ai.web_search.timeout")
+    if timeout <= 0:
+        raise ValueError("ai.web_search.timeout must be > 0")
+
+    extra_snippets = _parse_bool(
+        raw.get("extra_snippets", False),
+        field_name="ai.web_search.extra_snippets",
+    )
+
+    env_api_key = os.environ.get("BRAVE_API_KEY")
+    if env_api_key is not None:
+        api_key = env_api_key.strip() or None
+    if os.environ.get("BRAVE_SEARCH_COUNT") is not None:
+        count = min(
+            max(_parse_int(os.environ["BRAVE_SEARCH_COUNT"], field_name="BRAVE_SEARCH_COUNT"), 1),
+            20,
+        )
+    if os.environ.get("BRAVE_SEARCH_COUNTRY") is not None:
+        country = os.environ["BRAVE_SEARCH_COUNTRY"].strip().upper() or country
+    if os.environ.get("BRAVE_SEARCH_LANG") is not None:
+        search_lang = os.environ["BRAVE_SEARCH_LANG"].strip().lower() or search_lang
+    if os.environ.get("BRAVE_SEARCH_UI_LANG") is not None:
+        ui_lang = os.environ["BRAVE_SEARCH_UI_LANG"].strip() or ui_lang
+    if os.environ.get("BRAVE_SEARCH_SAFESEARCH") is not None:
+        safesearch = os.environ["BRAVE_SEARCH_SAFESEARCH"].strip().lower()
+        if safesearch not in {"off", "moderate", "strict"}:
+            raise ValueError("BRAVE_SEARCH_SAFESEARCH must be one of: off, moderate, strict")
+
+    return AIWebSearchConfig(
+        enabled=enabled,
+        api_key=api_key,
+        endpoint=endpoint,
+        count=count,
+        country=country,
+        search_lang=search_lang,
+        ui_lang=ui_lang,
+        safesearch=safesearch,
+        timeout=timeout,
+        extra_snippets=extra_snippets,
+    )
+
+
 def _parse_accounts(raw_accounts: Any, *, default_api_id: int | None, default_api_hash: str | None, default_session_dir: Path) -> list[AccountConfig]:
     if raw_accounts is None:
         return []
@@ -287,6 +383,8 @@ def _parse_ai_config(raw_ai: Any, *, root: Path) -> AIConfig | None:
     if tool_max_rounds < 1:
         raise ValueError("ai.tool_max_rounds must be >= 1")
 
+    web_search = _parse_web_search_config(raw_ai)
+
     return AIConfig(
         default_model=default_model,
         context_messages=context_messages,
@@ -295,6 +393,7 @@ def _parse_ai_config(raw_ai: Any, *, root: Path) -> AIConfig | None:
         models=models,
         workspace_dir=workspace_dir,
         tool_max_rounds=tool_max_rounds,
+        web_search=web_search,
     )