"""
SurfSense deep agent implementation.

This module provides the factory function for creating SurfSense deep agents
with configurable tools via the tools registry and configurable prompts
via NewLLMConfig.
"""

from collections.abc import Sequence

from deepagents import create_deep_agent
from langchain_core.tools import BaseTool
from langchain_litellm import ChatLiteLLM
from langgraph.types import Checkpointer
from sqlalchemy.ext.asyncio import AsyncSession

from app.agents.new_chat.context import SurfSenseContextSchema
from app.agents.new_chat.llm_config import AgentConfig
from app.agents.new_chat.system_prompt import (
    build_configurable_system_prompt,
    build_surfsense_system_prompt,
)
from app.agents.new_chat.tools.registry import build_tools_async
from app.services.connector_service import ConnectorService

# =============================================================================
# Deep Agent Factory
# =============================================================================


async def create_surfsense_deep_agent(
    llm: ChatLiteLLM,
    search_space_id: int,
    db_session: AsyncSession,
    connector_service: ConnectorService,
    checkpointer: Checkpointer,
    agent_config: AgentConfig | None = None,
    enabled_tools: list[str] | None = None,
    disabled_tools: list[str] | None = None,
    additional_tools: Sequence[BaseTool] | None = None,
    firecrawl_api_key: str | None = None,
):
    """
    Create a SurfSense deep agent with configurable tools and prompts.

    The agent comes with built-in tools that can be configured:
    - search_knowledge_base: Search the user's personal knowledge base
    - generate_podcast: Generate audio podcasts from content
    - link_preview: Fetch rich previews for URLs
    - display_image: Display images in chat
    - scrape_webpage: Extract content from webpages

    The agent also includes TodoListMiddleware by default (via create_deep_agent) which provides:
    - write_todos: Create and update planning/todo lists for complex tasks

    The system prompt can be configured via agent_config:
    - Custom system instructions (or use defaults)
    - Citation toggle (enable/disable citation requirements)

    Args:
        llm: ChatLiteLLM instance for the agent's language model
        search_space_id: The user's search space ID
        db_session: Database session for tools that need DB access
        connector_service: Initialized connector service for knowledge base search
        checkpointer: LangGraph checkpointer for conversation state persistence.
                      Use AsyncPostgresSaver for production or MemorySaver for testing.
        agent_config: Optional AgentConfig from NewLLMConfig for prompt configuration.
                     If None, uses default system prompt with citations enabled.
        enabled_tools: Explicit list of tool names to enable. If None, all default tools
                      are enabled. Use this to limit which tools are available.
        disabled_tools: List of tool names to disable. Applied after enabled_tools.
                       Use this to exclude specific tools from the defaults.
        additional_tools: Extra custom tools to add beyond the built-in ones.
                         These are always added regardless of enabled/disabled settings.
        firecrawl_api_key: Optional Firecrawl API key for premium web scraping.
                          Falls back to Chromium/Trafilatura if not provided.

    Returns:
        CompiledStateGraph: The configured deep agent

    Examples:
        # Create agent with all default tools and default prompt
        agent = create_surfsense_deep_agent(llm, search_space_id, db_session, ...)

        # Create agent with custom prompt configuration
        agent = create_surfsense_deep_agent(
            llm, search_space_id, db_session, ...,
            agent_config=AgentConfig(
                provider="OPENAI",
                model_name="gpt-4",
                api_key="...",
                system_instructions="Custom instructions...",
                citations_enabled=False,
            )
        )

        # Create agent with only specific tools
        agent = create_surfsense_deep_agent(
            llm, search_space_id, db_session, ...,
            enabled_tools=["search_knowledge_base", "link_preview"]
        )

        # Create agent without podcast generation
        agent = create_surfsense_deep_agent(
            llm, search_space_id, db_session, ...,
            disabled_tools=["generate_podcast"]
        )

        # Add custom tools
        agent = create_surfsense_deep_agent(
            llm, search_space_id, db_session, ...,
            additional_tools=[my_custom_tool]
        )
    """
    # Build dependencies dict for the tools registry
    dependencies = {
        "search_space_id": search_space_id,
        "db_session": db_session,
        "connector_service": connector_service,
        "firecrawl_api_key": firecrawl_api_key,
    }

    # Build tools using the async registry (includes MCP tools)
    tools = await build_tools_async(
        dependencies=dependencies,
        enabled_tools=enabled_tools,
        disabled_tools=disabled_tools,
        additional_tools=list(additional_tools) if additional_tools else None,
    )

    # Build system prompt based on agent_config
    if agent_config is not None:
        # Use configurable prompt with settings from NewLLMConfig
        system_prompt = build_configurable_system_prompt(
            custom_system_instructions=agent_config.system_instructions,
            use_default_system_instructions=agent_config.use_default_system_instructions,
            citations_enabled=agent_config.citations_enabled,
        )
    else:
        # Use default prompt (with citations enabled)
        system_prompt = build_surfsense_system_prompt()

    # Create the deep agent with system prompt and checkpointer
    # Note: TodoListMiddleware (write_todos) is included by default in create_deep_agent
    agent = create_deep_agent(
        model=llm,
        tools=tools,
        system_prompt=system_prompt,
        context_schema=SurfSenseContextSchema,
        checkpointer=checkpointer,
    )

    return agent