"""
CodeAgent: A LangGraph-based agent for executing Python code and using tools.
Fully modular version with unified tool management.
"""

import os
import re
import time
from typing import Dict, List, Optional
from jinja2 import Template
from langchain_core.language_models.chat_models import BaseChatModel
from langchain_core.messages import AIMessage, BaseMessage, HumanMessage, SystemMessage
from langchain_openai import ChatOpenAI
from dotenv import load_dotenv

# Import core types and constants
from core.types import AgentState, AgentConfig
from core.constants import SYSTEM_PROMPT_TEMPLATE

# Import managers (organized by subsystem)
from managers import (
    # Support
    PackageManager,
    ConsoleDisplay,
    # Workflow
    PlanManager,
    StateManager,
    WorkflowEngine,
    # Tools
    ToolManager,
    ToolSource,
    ToolSelector,
    # Execution
    Timing,
    PythonExecutor
)

# Load environment variables
load_dotenv("./.env")


def get_system_prompt(functions: Dict[str, dict], packages: Dict[str, str] = None) -> str:
    """Generate system prompt using template and functions."""
    if packages is None:
        from core.constants import LIBRARY_CONTENT_DICT
        packages = LIBRARY_CONTENT_DICT
    return Template(SYSTEM_PROMPT_TEMPLATE).render(functions=functions, packages=packages)


class CodeAgent:
    """A code-based agent that can execute Python code and use tools to solve tasks."""

    def __init__(self, model: BaseChatModel,
                 config: Optional[AgentConfig] = None,
                 use_tool_manager: bool = True,
                 use_tool_selection: bool = True):
        """
        Initialize the CodeAgent with unified tool management.

        Args:
            model: The language model to use for generation
            config: Configuration for the agent
            use_tool_manager: Whether to use the unified ToolManager (recommended)
            use_tool_selection: Whether to use LLM-based tool selection (like Biomni)
        """
        self.model = model
        self.config = config or AgentConfig()
        self.use_tool_manager = use_tool_manager
        self.use_tool_selection = use_tool_selection

        # Cache selected tools to avoid re-selection at each step
        self._selected_tools_cache = None

        # Initialize modular components
        self.package_manager = PackageManager()
        self.console = ConsoleDisplay()
        self.state_manager = StateManager()
        self.plan_manager = PlanManager()

        # Initialize unified tool management
        if not self.use_tool_manager:
            raise ValueError("ToolManager is required. Legacy mode (use_tool_manager=False) has been removed.")

        self.tool_manager = ToolManager(self.console)

        # Initialize tool selector for LLM-based tool selection
        if self.use_tool_selection:
            self.tool_selector = ToolSelector(self.model)
        else:
            self.tool_selector = None

        # Initialize workflow engine
        self.workflow_engine = WorkflowEngine(model, self.config, self.console, self.state_manager)

        # Initialize Python executor
        self.python_executor = PythonExecutor()

        # Setup workflow
        self._setup_workflow()

    # ====================
    # WORKFLOW SETUP
    # ====================

    def _setup_workflow(self):
        """Setup the LangGraph workflow using WorkflowEngine."""
        self.workflow_engine.setup_workflow(
            self.generate,
            self.execute,
            self.should_continue
        )

    # ====================
    # WORKFLOW NODES
    # ====================

    def generate(self, state: AgentState) -> AgentState:
        """Generate response using LLM with tool-aware prompt."""

        # Get all available tools first
        all_schemas = self.tool_manager.get_tool_schemas(openai_format=True)
        all_functions_dict = {schema['function']['name']: schema for schema in all_schemas}

        # Use tool selection if enabled and not cached
        if self.use_tool_selection and self.tool_selector and state.get("messages") and self._selected_tools_cache is None:
            # Get the user's query from the first message
            user_query = ""
            for msg in state["messages"]:
                if hasattr(msg, 'content') and msg.content:
                    user_query = msg.content
                    break

            if user_query:
                # Prepare tools for selection (convert schemas to tool info format)
                available_tools = {}
                for tool_name, schema in all_functions_dict.items():
                    available_tools[tool_name] = {
                        'description': schema['function'].get('description', 'No description'),
                        'source': 'tool_manager'  # Could be enhanced to show actual source
                    }

                # Select relevant tools using LLM (only once)
                selected_tool_names = self.tool_selector.select_tools_for_task(
                    user_query, available_tools, max_tools=15
                )

                # Cache the selected tools
                self._selected_tools_cache = {name: all_functions_dict[name]
                                            for name in selected_tool_names
                                            if name in all_functions_dict}

                self.console.console.print(f"🎯 Selected {len(self._selected_tools_cache)} tools from {len(all_functions_dict)} available tools (cached for session)")
                functions_dict = self._selected_tools_cache
            else:
                functions_dict = all_functions_dict
        elif self.use_tool_selection and self._selected_tools_cache is not None:
            # Use cached selected tools
            functions_dict = self._selected_tools_cache
        else:
            # No tool selection or selection disabled
            functions_dict = all_functions_dict

        all_packages = self.package_manager.get_all_packages()
        system_prompt = get_system_prompt(functions_dict, all_packages)

        # Truncate conversation history to prevent context overflow
        messages = [SystemMessage(content=system_prompt)] + state["messages"]

        response = self.model.invoke(messages)

        # Cut the text after the </execute> tag, while keeping the </execute> tag
        if "</execute>" in response.content:
            response.content = response.content.split("</execute>")[0] + "</execute>"

        # Parse the response
        msg = str(response.content)
        llm_reply = AIMessage(content=msg.strip())

        # Update step count
        new_step_count = state.get("step_count", 0) + 1

        return self.state_manager.create_state_dict(
            messages=[llm_reply],
            step_count=new_step_count,
            error_count=state.get("error_count", 0),
            start_time=state.get("start_time", time.time()),
            current_plan=self._extract_current_plan(msg)
        )

    def _extract_current_plan(self, content: str) -> Optional[str]:
        """Extract the current plan from the agent's response."""
        return self.plan_manager.extract_plan_from_content(content)

    def execute(self, state: AgentState) -> AgentState:
        """Execute code using persistent Python executor."""
        try:
            last_message = state["messages"][-1].content
            execute_match = re.search(r"<execute>(.*?)</execute>", last_message, re.DOTALL)

            if execute_match:
                code = execute_match.group(1).strip()

                # Execute regular code in persistent environment (tools already injected)
                result = self.python_executor(code)

                # Include both the code and result in the observation
                obs = f"\n<observation>\nCode Output:\n{result}</observation>"
                return self.state_manager.create_state_dict(
                    messages=[AIMessage(content=obs.strip())],
                    step_count=state.get("step_count", 0),
                    error_count=state.get("error_count", 0),
                    start_time=state.get("start_time", time.time()),
                    current_plan=state.get("current_plan")
                )
            else:
                return self.state_manager.create_state_dict(
                    messages=[AIMessage(content="<error>No executable code found</error>")],
                    step_count=state.get("step_count", 0),
                    error_count=state.get("error_count", 0) + 1,
                    start_time=state.get("start_time", time.time()),
                    current_plan=state.get("current_plan")
                )
        except Exception as e:
            return self.state_manager.create_state_dict(
                messages=[AIMessage(content=f"<error>Execution error: {str(e)}</error>")],
                step_count=state.get("step_count", 0),
                error_count=state.get("error_count", 0) + 1,
                start_time=state.get("start_time", time.time()),
                current_plan=state.get("current_plan")
            )

    def should_continue(self, state: AgentState) -> str:
        """Decide whether to continue executing or end the workflow."""
        last_message = state["messages"][-1].content
        step_count = state.get("step_count", 0)
        error_count = state.get("error_count", 0)
        start_time = state.get("start_time", time.time())

        # Check for timeout
        if time.time() - start_time > self.config.timeout_seconds:
            return "end"

        # Check for maximum steps
        if step_count >= self.config.max_steps:
            return "end"

        # Check for too many errors
        if error_count >= self.config.retry_attempts:
            return "end"

        # Check if the finish() tool has been called
        if "<solution>" in last_message and "</solution>" in last_message:
            return "end"

        # Check if there's an execute tag in the last message
        elif "<execute>" in last_message and "</execute>" in last_message:
            return "execute"

        else:
            return "end"

    # ====================
    # PACKAGE MANAGEMENT - Delegated to PackageManager
    # ====================

    def add_packages(self, packages: Dict[str, str]) -> bool:
        """Add new packages to the available packages."""
        return self.package_manager.add_packages(packages)

    def get_all_packages(self) -> Dict[str, str]:
        """Get all available packages (default + custom)."""
        return self.package_manager.get_all_packages()

    # ====================
    # UNIFIED TOOL MANAGEMENT - Delegated to ToolManager
    # ====================

    def add_tool(self, function: callable, name: str = None, description: str = None) -> bool:
        """Add a tool function to the manager."""
        return self.tool_manager.add_tool(function, name, description, ToolSource.LOCAL)

    def remove_tool(self, name: str) -> bool:
        """Remove a tool by name."""
        return self.tool_manager.remove_tool(name)

    def list_tools(self, source: str = "all", include_details: bool = False) -> List[Dict]:
        """List all available tools with optional filtering."""
        source_enum = ToolSource.ALL
        if source.lower() in ["local", "decorated", "mcp"]:
            source_enum = ToolSource(source.lower())

        return self.tool_manager.list_tools(source_enum, include_details)

    def search_tools(self, query: str) -> List[Dict]:
        """Search tools by name and description."""
        return self.tool_manager.search_tools(query)

    def get_tool_info(self, name: str) -> Optional[Dict]:
        """Get detailed information about a specific tool."""
        tool_info = self.tool_manager.get_tool(name)
        if tool_info:
            return {
                "name": tool_info.name,
                "description": tool_info.description,
                "source": tool_info.source.value,
                "server": tool_info.server,
                "module": tool_info.module,
                "has_function": tool_info.function is not None,
                "required_parameters": tool_info.required_parameters,
                "optional_parameters": tool_info.optional_parameters
            }
        return None

    def get_all_tool_functions(self) -> Dict[str, callable]:
        """Get all tool functions as a dictionary."""
        return self.tool_manager.get_all_functions()

    # ====================
    # MCP METHODS - Now delegated to ToolManager
    # ====================

    def add_mcp(self, config_path: str = "./mcp_config.yaml") -> None:
        """Add MCP tools from configuration file."""
        self.tool_manager.add_mcp_server(config_path)

    def list_mcp_tools(self) -> List[Dict]:
        """List all loaded MCP tools."""
        return self.tool_manager.list_tools(self.tool_manager.ToolSource.MCP)

    def list_mcp_servers(self) -> Dict[str, List[str]]:
        """List all MCP servers and their tools."""
        return self.tool_manager.list_mcp_servers()

    def show_mcp_status(self) -> None:
        """Display detailed MCP status information to the user."""
        self.tool_manager.show_mcp_status()

    def get_mcp_summary(self) -> Dict[str, any]:
        """Get a summary of MCP tools for programmatic access."""
        return self.tool_manager.get_mcp_summary()

    # ====================
    # ENHANCED TOOL FEATURES
    # ====================

    def get_tool_statistics(self) -> Dict[str, any]:
        """Get comprehensive tool statistics."""
        return self.tool_manager.get_tool_statistics()

    def validate_tools(self) -> Dict[str, List[str]]:
        """Validate all tools and return any issues."""
        return self.tool_manager.validate_tools()

    # ====================
    # TOOL SELECTION MANAGEMENT
    # ====================

    def reset_tool_selection(self):
        """Reset the cached tool selection to allow re-selection on next query."""
        self._selected_tools_cache = None
        if self.use_tool_selection:
            self.console.console.print("🔄 Tool selection cache cleared - will re-select tools on next query")

    def get_selected_tools(self):
        """Get the currently selected tools (if any)."""
        return list(self._selected_tools_cache.keys()) if self._selected_tools_cache else None

    # ====================
    # TRACE AND SUMMARY METHODS
    # ====================

    def get_trace(self) -> Dict:
        """Get the complete trace of the last execution."""
        if not self.workflow_engine:
            return {}

        return {
            "execution_time": time.strftime('%Y-%m-%d %H:%M:%S'),
            "config": {
                "max_steps": self.config.max_steps,
                "timeout_seconds": self.config.timeout_seconds,
                "verbose": self.config.verbose
            },
            "messages": self.workflow_engine.message_history,
            "trace_logs": self.workflow_engine.trace_logs
        }

    def get_summary(self) -> Dict:
        """Get a summary of the last execution."""
        if not self.workflow_engine:
            return {}
        return self.workflow_engine.generate_summary()

    def save_trace(self, filepath: str = None) -> str:
        """Save the trace of the last execution to a file."""
        if not self.workflow_engine:
            raise RuntimeError("No workflow engine available")
        return self.workflow_engine.save_trace_to_file(filepath)

    def save_summary(self, filepath: str = None) -> str:
        """Save the summary of the last execution to a file."""
        if not self.workflow_engine:
            raise RuntimeError("No workflow engine available")
        return self.workflow_engine.save_summary_to_file(filepath)

    # ====================
    # PUBLIC INTERFACE
    # ====================

    def run(self, query: str, save_trace: bool = False, save_summary: bool = False,
            trace_dir: str = "traces") -> str:
        """
        Run the agent with a given query using modular components.

        Args:
            query: The task/question to solve
            save_trace: Whether to save the complete trace to a file
            save_summary: Whether to save the execution summary to a file
            trace_dir: Directory to save trace and summary files

        Returns:
            The final response content
        """
        # Start timing the overall execution
        overall_timing = Timing(start_time=time.time())

        # Display task header
        self.console.print_task_header(query)

        # Initialize agent with functions using ToolManager
        functions_dict = self.get_all_tool_functions()

        # Display enhanced tool information
        # Get detailed tool statistics
        stats = self.tool_manager.get_tool_statistics()
        mcp_servers = self.tool_manager.list_mcp_servers()

        self.console.console.print(f"🛠️  Loaded {stats['total_tools']} total tools:")
        if stats['by_source']['local'] > 0:
            self.console.console.print(f"   📋 Local tools: {stats['by_source']['local']}")
        if stats['by_source']['decorated'] > 0:
            self.console.console.print(f"   🎯 Decorated tools: {stats['by_source']['decorated']}")
        if stats['by_source']['mcp'] > 0:
            self.console.console.print(f"   🔗 MCP tools: {stats['by_source']['mcp']} from {len(mcp_servers)} servers")
            for server_name, tools in mcp_servers.items():
                self.console.console.print(f"      • {server_name}: {len(tools)} tools")

        # Inject functions into Python executor
        self.python_executor.send_functions(functions_dict)

        # Import available packages using PackageManager
        imported_packages, failed_packages = self.package_manager.import_packages(self.python_executor)
        self.console.print_packages_info(imported_packages, failed_packages)

        # Inject any initial variables
        state_variables = {}
        self.python_executor.send_variables(state_variables)

        # Create initial state using StateManager
        input_state = self.state_manager.create_state_dict(
            messages=[HumanMessage(content=query)],
            step_count=0,
            error_count=0,
            start_time=time.time(),
            current_plan=None
        )

        # Execute workflow using WorkflowEngine and get result with final state
        result, final_state = self.workflow_engine.run_workflow(input_state)

        # Complete overall timing and display summary
        overall_timing.end_time = time.time()

        # Extract final state information for summary
        final_step_count = final_state.get("step_count", 0) if final_state else 0
        final_error_count = final_state.get("error_count", 0) if final_state else 0

        self.console.print_execution_summary(final_step_count, final_error_count, overall_timing.duration)

        # Save trace and summary if requested
        if save_trace or save_summary:
            # Create trace directory if it doesn't exist
            from pathlib import Path
            trace_path = Path(trace_dir)
            trace_path.mkdir(parents=True, exist_ok=True)

            if save_trace:
                trace_file = trace_path / f"agent_trace_{time.strftime('%Y%m%d_%H%M%S')}.json"
                saved_trace = self.workflow_engine.save_trace_to_file(str(trace_file))
                self.console.console.print(f"💾 Trace saved to: {saved_trace}")

            if save_summary:
                summary_file = trace_path / f"agent_summary_{time.strftime('%Y%m%d_%H%M%S')}.json"
                saved_summary = self.workflow_engine.save_summary_to_file(str(summary_file))
                self.console.console.print(f"📊 Summary saved to: {saved_summary}")

        return result


# ====================
# EXAMPLE USAGE
# ====================

if __name__ == "__main__":
    # Example usage of the fully modular CodeAgent architecture
    # Create LLM client
    model = ChatOpenAI(
        model="google/gemini-2.5-flash",
        base_url="https://openrouter.ai/api/v1",
        temperature=0.7,
        api_key=os.environ["OPENROUTER_API_KEY"],
    )
    
    model = ChatAnthropic(model='claude-sonnet-4-5-20250929')
    
    

    # Create configuration
    config = AgentConfig(
        max_steps=15,
        max_conversation_length=30,
        retry_attempts=3,
        timeout_seconds=1200,
        verbose=True
    )

    # Create agent with unified tool management and LLM-based tool selection
    agent = CodeAgent(model=model, config=config, use_tool_manager=True, use_tool_selection=True)

    # Demonstrate tool management capabilities
    print("\n🔧 Tool Management Demo:")

    # Show tool statistics
    stats = agent.get_tool_statistics()
    print(f"📊 Tool Statistics: {stats}")

    # Add MCP tools
    try:
        print("🔧 Loading MCP tools...")
        script_dir = os.path.dirname(os.path.abspath(__file__))
        config_path = os.path.join(script_dir, "mcp_config.yaml")
        agent.add_mcp(config_path)
        print("✅ MCP tools loaded successfully!")

        # Show enhanced MCP status
        agent.show_mcp_status()

        # Show all available tools by source
        all_tools = agent.list_tools("all", include_details=True)
        print(f"\n📋 All tools loaded:")
        for tool in all_tools:
            print(f"   • {tool['name']} ({tool['source']}) - {tool['description'][:50]}...")

    except Exception as e:
        print(f"⚠️ Could not load MCP tools: {e}")

    # Validate tools
    issues = agent.validate_tools()
    if any(issues.values()):
        print(f"⚠️  Tool validation issues: {issues}")
    else:
        print("✅ All tools validated successfully!")
    # List available packages
    print(f"\n📦 Available packages: {list(agent.get_all_packages().keys())}")
    # Run the agent with a query and save trace/summary
    print("\n🚀 Running agent with trace and summary saving...")
    result = agent.run(
        query="""
        Use AlphaGenome MCP to analyze heart gene expression data to identify the causal gene
        for the variant chr11:116837649:T>G, associated with Hypoalphalipoproteinemia. My API key is: AIzaSyD1USDNy9WqfIROICB3FWI1wJHmkO2z21U.
        """,
        save_trace=True,      # Save complete execution trace
        save_summary=True,    # Save execution summary
        trace_dir="traces"    # Directory to save files
    )

    # You can also access trace and summary programmatically
    print("\n📊 Execution Summary:")
    summary = agent.get_summary()
    print(f"   Total steps: {summary.get('total_steps', 0)}")
    print(f"   Code executions: {len(summary.get('code_executions', []))}")
    print(f"   Observations: {len(summary.get('observations', []))}")
    print(f"   Errors: {len(summary.get('errors', []))}")

    # You can save trace/summary manually after execution
    # agent.save_trace("custom_trace.json")
    # agent.save_summary("custom_summary.json")