autocoder/server/services/spec_chat_session.py

"""
Spec Creation Chat Session
==========================

Manages interactive spec creation conversation with Claude.
Uses the create-spec.md skill to guide users through app spec creation.
"""

import asyncio
import logging
import shutil
import threading
from datetime import datetime
from pathlib import Path
from typing import AsyncGenerator, Optional

from claude_agent_sdk import ClaudeAgentOptions, ClaudeSDKClient

logger = logging.getLogger(__name__)

# Root directory of the project
ROOT_DIR = Path(__file__).parent.parent.parent


class SpecChatSession:
    """
    Manages a spec creation conversation for one project.

    Uses the create-spec skill to guide users through:
    - Phase 1: Project Overview (name, description, audience)
    - Phase 2: Involvement Level (Quick vs Detailed mode)
    - Phase 3: Technology Preferences
    - Phase 4: Features (main exploration phase)
    - Phase 5: Technical Details (derived or discussed)
    - Phase 6-7: Success Criteria & Approval
    """

    def __init__(self, project_name: str, project_dir: Path):
        """
        Initialize the session.

        Args:
            project_name: Name of the project being created
            project_dir: Absolute path to the project directory
        """
        self.project_name = project_name
        self.project_dir = project_dir
        self.client: Optional[ClaudeSDKClient] = None
        self.messages: list[dict] = []
        self.complete: bool = False
        self.created_at = datetime.now()
        self._conversation_id: Optional[str] = None
        self._client_entered: bool = False  # Track if context manager is active

    async def close(self) -> None:
        """Clean up resources and close the Claude client."""
        if self.client and self._client_entered:
            try:
                await self.client.__aexit__(None, None, None)
            except Exception as e:
                logger.warning(f"Error closing Claude client: {e}")
            finally:
                self._client_entered = False
                self.client = None

    async def start(self) -> AsyncGenerator[dict, None]:
        """
        Initialize session and get initial greeting from Claude.

        Yields message chunks as they stream in.
        """
        # Load the create-spec skill
        skill_path = ROOT_DIR / ".claude" / "commands" / "create-spec.md"

        if not skill_path.exists():
            yield {
                "type": "error",
                "content": f"Spec creation skill not found at {skill_path}"
            }
            return

        try:
            skill_content = skill_path.read_text(encoding="utf-8")
        except UnicodeDecodeError:
            skill_content = skill_path.read_text(encoding="utf-8", errors="replace")

        # Ensure project directory exists (like CLI does in start.py)
        self.project_dir.mkdir(parents=True, exist_ok=True)

        # Replace $ARGUMENTS with absolute project path (like CLI does in start.py:184)
        # Using absolute path avoids confusion when project folder name differs from app name
        project_path = str(self.project_dir.resolve())
        system_prompt = skill_content.replace("$ARGUMENTS", project_path)

        # Create Claude SDK client with limited tools for spec creation
        # Use Opus for best quality spec generation
        # Use system CLI to avoid bundled Bun runtime crash (exit code 3) on Windows
        system_cli = shutil.which("claude")
        try:
            self.client = ClaudeSDKClient(
                options=ClaudeAgentOptions(
                    model="claude-opus-4-5-20251101",
                    cli_path=system_cli,
                    system_prompt=system_prompt,
                    allowed_tools=[
                        "Read",
                        "Write",
                        "Edit",
                        "Glob",
                    ],
                    permission_mode="acceptEdits",  # Auto-approve file writes for spec creation
                    max_turns=100,
                    cwd=str(ROOT_DIR.resolve()),
                )
            )
            # Enter the async context and track it
            await self.client.__aenter__()
            self._client_entered = True
        except Exception as e:
            logger.exception("Failed to create Claude client")
            yield {
                "type": "error",
                "content": f"Failed to initialize Claude: {str(e)}"
            }
            return

        # Start the conversation - Claude will send the Phase 1 greeting
        try:
            async for chunk in self._query_claude("Begin the spec creation process."):
                yield chunk
            # Signal that the response is complete (for UI to hide loading indicator)
            yield {"type": "response_done"}
        except Exception as e:
            logger.exception("Failed to start spec chat")
            yield {
                "type": "error",
                "content": f"Failed to start conversation: {str(e)}"
            }

    async def send_message(self, user_message: str) -> AsyncGenerator[dict, None]:
        """
        Send user message and stream Claude's response.

        Args:
            user_message: The user's response

        Yields:
            Message chunks of various types:
            - {"type": "text", "content": str}
            - {"type": "question", "questions": list}
            - {"type": "spec_complete", "path": str}
            - {"type": "error", "content": str}
        """
        if not self.client:
            yield {
                "type": "error",
                "content": "Session not initialized. Call start() first."
            }
            return

        # Store the user message
        self.messages.append({
            "role": "user",
            "content": user_message,
            "timestamp": datetime.now().isoformat()
        })

        try:
            async for chunk in self._query_claude(user_message):
                yield chunk
            # Signal that the response is complete (for UI to hide loading indicator)
            yield {"type": "response_done"}
        except Exception as e:
            logger.exception("Error during Claude query")
            yield {
                "type": "error",
                "content": f"Error: {str(e)}"
            }

    async def _query_claude(self, message: str) -> AsyncGenerator[dict, None]:
        """
        Internal method to query Claude and stream responses.

        Handles tool calls (Write) and text responses.

        IMPORTANT: Spec creation requires BOTH files to be written:
        1. app_spec.txt - the main specification
        2. initializer_prompt.md - tells the agent how many features to create

        We only signal spec_complete when BOTH files are verified on disk.
        """
        if not self.client:
            return

        # Send the message to Claude using the SDK's query method
        await self.client.query(message)

        current_text = ""

        # Track pending writes for BOTH required files
        pending_writes = {
            "app_spec": None,      # {"tool_id": ..., "path": ...}
            "initializer": None,   # {"tool_id": ..., "path": ...}
        }

        # Track which files have been successfully written
        files_written = {
            "app_spec": False,
            "initializer": False,
        }

        # Store paths for the completion message
        spec_path = None

        # Stream the response using receive_response
        async for msg in self.client.receive_response():
            msg_type = type(msg).__name__

            if msg_type == "AssistantMessage" and hasattr(msg, "content"):
                # Process content blocks in the assistant message
                for block in msg.content:
                    block_type = type(block).__name__

                    if block_type == "TextBlock" and hasattr(block, "text"):
                        # Accumulate text and yield it
                        text = block.text
                        if text:
                            current_text += text
                            yield {"type": "text", "content": text}

                            # Store in message history
                            self.messages.append({
                                "role": "assistant",
                                "content": text,
                                "timestamp": datetime.now().isoformat()
                            })

                    elif block_type == "ToolUseBlock" and hasattr(block, "name"):
                        tool_name = block.name
                        tool_input = getattr(block, "input", {})
                        tool_id = getattr(block, "id", "")

                        if tool_name in ("Write", "Edit"):
                            # File being written or edited - track for verification
                            file_path = tool_input.get("file_path", "")

                            # Track app_spec.txt
                            if "app_spec.txt" in str(file_path):
                                pending_writes["app_spec"] = {
                                    "tool_id": tool_id,
                                    "path": file_path
                                }
                                logger.info(f"{tool_name} tool called for app_spec.txt: {file_path}")

                            # Track initializer_prompt.md
                            elif "initializer_prompt.md" in str(file_path):
                                pending_writes["initializer"] = {
                                    "tool_id": tool_id,
                                    "path": file_path
                                }
                                logger.info(f"{tool_name} tool called for initializer_prompt.md: {file_path}")

            elif msg_type == "UserMessage" and hasattr(msg, "content"):
                # Tool results - check for write confirmations and errors
                for block in msg.content:
                    block_type = type(block).__name__
                    if block_type == "ToolResultBlock":
                        is_error = getattr(block, "is_error", False)
                        tool_use_id = getattr(block, "tool_use_id", "")

                        if is_error:
                            content = getattr(block, "content", "Unknown error")
                            logger.warning(f"Tool error: {content}")
                            # Clear any pending writes that failed
                            for key in pending_writes:
                                if pending_writes[key] and tool_use_id == pending_writes[key].get("tool_id"):
                                    logger.error(f"{key} write failed: {content}")
                                    pending_writes[key] = None
                        else:
                            # Tool succeeded - check which file was written

                            # Check app_spec.txt
                            if pending_writes["app_spec"] and tool_use_id == pending_writes["app_spec"].get("tool_id"):
                                file_path = pending_writes["app_spec"]["path"]
                                full_path = ROOT_DIR / file_path
                                if full_path.exists():
                                    logger.info(f"app_spec.txt verified at: {full_path}")
                                    files_written["app_spec"] = True
                                    spec_path = file_path

                                    # Notify about file write (but NOT completion yet)
                                    yield {
                                        "type": "file_written",
                                        "path": str(file_path)
                                    }
                                else:
                                    logger.error(f"app_spec.txt not found after write: {full_path}")
                                pending_writes["app_spec"] = None

                            # Check initializer_prompt.md
                            if pending_writes["initializer"] and tool_use_id == pending_writes["initializer"].get("tool_id"):
                                file_path = pending_writes["initializer"]["path"]
                                full_path = ROOT_DIR / file_path
                                if full_path.exists():
                                    logger.info(f"initializer_prompt.md verified at: {full_path}")
                                    files_written["initializer"] = True

                                    # Notify about file write
                                    yield {
                                        "type": "file_written",
                                        "path": str(file_path)
                                    }
                                else:
                                    logger.error(f"initializer_prompt.md not found after write: {full_path}")
                                pending_writes["initializer"] = None

                            # Check if BOTH files are now written - only then signal completion
                            if files_written["app_spec"] and files_written["initializer"]:
                                logger.info("Both app_spec.txt and initializer_prompt.md verified - signaling completion")
                                self.complete = True
                                yield {
                                    "type": "spec_complete",
                                    "path": str(spec_path)
                                }

    def is_complete(self) -> bool:
        """Check if spec creation is complete."""
        return self.complete

    def get_messages(self) -> list[dict]:
        """Get all messages in the conversation."""
        return self.messages.copy()


# Session registry with thread safety
_sessions: dict[str, SpecChatSession] = {}
_sessions_lock = threading.Lock()


def get_session(project_name: str) -> Optional[SpecChatSession]:
    """Get an existing session for a project."""
    with _sessions_lock:
        return _sessions.get(project_name)


async def create_session(project_name: str, project_dir: Path) -> SpecChatSession:
    """Create a new session for a project, closing any existing one.

    Args:
        project_name: Name of the project
        project_dir: Absolute path to the project directory
    """
    old_session: Optional[SpecChatSession] = None

    with _sessions_lock:
        # Get existing session to close later (outside the lock)
        old_session = _sessions.pop(project_name, None)
        session = SpecChatSession(project_name, project_dir)
        _sessions[project_name] = session

    # Close old session outside the lock to avoid blocking
    if old_session:
        try:
            await old_session.close()
        except Exception as e:
            logger.warning(f"Error closing old session for {project_name}: {e}")

    return session


async def remove_session(project_name: str) -> None:
    """Remove and close a session."""
    session: Optional[SpecChatSession] = None

    with _sessions_lock:
        session = _sessions.pop(project_name, None)

    # Close session outside the lock
    if session:
        try:
            await session.close()
        except Exception as e:
            logger.warning(f"Error closing session for {project_name}: {e}")


def list_sessions() -> list[str]:
    """List all active session project names."""
    with _sessions_lock:
        return list(_sessions.keys())


async def cleanup_all_sessions() -> None:
    """Close all active sessions. Called on server shutdown."""
    sessions_to_close: list[SpecChatSession] = []

    with _sessions_lock:
        sessions_to_close = list(_sessions.values())
        _sessions.clear()

    for session in sessions_to_close:
        try:
            await session.close()
        except Exception as e:
            logger.warning(f"Error closing session {session.project_name}: {e}")