init commit

app/models/config.py

@@ -0,0 +1,127 @@
+"""Pydantic configuration models mapping to config/config.yaml."""
+
+import os
+from pathlib import Path
+
+import yaml
+from pydantic import BaseModel, Field, model_validator
+
+
+class LLMConfig(BaseModel):
+    """LLM backend configuration."""
+
+    model: str = Field(description="Model name to use")
+    endpoint: str = Field(description="Base URL of the LLM API")
+    api_path: str = Field(default="/v1/chat/completions", description="API endpoint path")
+    temperature: float = Field(default=0.1, description="Sampling temperature")
+    max_tokens: int = Field(default=4096, description="Maximum tokens in LLM response")
+    timeout: int = Field(default=120, description="Request timeout in seconds")
+
+
+class AgentConfig(BaseModel):
+    """Agent loop configuration."""
+
+    max_iterations: int = Field(default=25, description="Maximum tool-call loop iterations")
+    max_conversation_tokens: int = Field(
+        default=32000, description="Token budget for conversation history"
+    )
+    workspace_root: Path = Field(
+        default=Path("."), description="Root directory for file operations"
+    )
+
+
+class PermissionsConfig(BaseModel):
+    """Tool permission tiers."""
+
+    auto_approve: list[str] = Field(default_factory=list, description="Auto-approved tools")
+    prompt_user: list[str] = Field(default_factory=list, description="Tools requiring confirmation")
+    deny: list[str] = Field(default_factory=list, description="Tools that are blocked entirely")
+
+
+class ShellToolConfig(BaseModel):
+    """Shell tool restrictions."""
+
+    allowed_commands: list[str] = Field(default_factory=list, description="Allowed shell commands")
+    denied_commands: list[str] = Field(default_factory=list, description="Blocked shell commands")
+    max_output_bytes: int = Field(default=65536, description="Max output capture size in bytes")
+
+
+class FilesystemToolConfig(BaseModel):
+    """Filesystem tool limits."""
+
+    max_file_size_bytes: int = Field(default=1_048_576, description="Max file size for read/write")
+    binary_detection: bool = Field(default=True, description="Detect and reject binary files")
+
+
+class ToolsConfig(BaseModel):
+    """Aggregate tool configuration."""
+
+    shell: ShellToolConfig = Field(default_factory=ShellToolConfig)
+    filesystem: FilesystemToolConfig = Field(default_factory=FilesystemToolConfig)
+
+
+class DisplayConfig(BaseModel):
+    """Terminal display preferences."""
+
+    show_tool_calls: bool = Field(default=True, description="Show tool call details in output")
+    show_token_usage: bool = Field(default=True, description="Show token usage stats")
+    stream_output: bool = Field(default=True, description="Stream LLM output to terminal")
+
+
+class AppConfig(BaseModel):
+    """Top-level application configuration composing all sub-configs."""
+
+    llm: LLMConfig
+    agent: AgentConfig = Field(default_factory=AgentConfig)
+    permissions: PermissionsConfig = Field(default_factory=PermissionsConfig)
+    tools: ToolsConfig = Field(default_factory=ToolsConfig)
+    display: DisplayConfig = Field(default_factory=DisplayConfig)
+
+    @model_validator(mode="after")
+    def resolve_workspace_root(self) -> "AppConfig":
+        """Resolve workspace_root to an absolute path."""
+        self.agent.workspace_root = self.agent.workspace_root.resolve()
+        return self
+
+
+# Default config file location relative to project root
+_DEFAULT_CONFIG_PATH = Path("config/config.yaml")
+
+
+def load_config(config_path: Path | None = None) -> AppConfig:
+    """Load and validate application config from YAML.
+
+    Resolution order:
+    1. Explicit config_path argument
+    2. SNEAKYCODE_CONFIG environment variable
+    3. config/config.yaml (default)
+
+    Args:
+        config_path: Optional explicit path to config file.
+
+    Returns:
+        Validated AppConfig instance.
+
+    Raises:
+        FileNotFoundError: If the resolved config file does not exist.
+        ValueError: If the config file is invalid YAML or fails validation.
+    """
+    if config_path is None:
+        env_path = os.environ.get("SNEAKYCODE_CONFIG")
+        if env_path:
+            config_path = Path(env_path)
+        else:
+            config_path = _DEFAULT_CONFIG_PATH
+
+    config_path = config_path.resolve()
+
+    if not config_path.exists():
+        raise FileNotFoundError(f"Config file not found: {config_path}")
+
+    with open(config_path) as f:
+        raw = yaml.safe_load(f)
+
+    if not isinstance(raw, dict):
+        raise ValueError(f"Config file must contain a YAML mapping, got {type(raw).__name__}")
+
+    return AppConfig(**raw)