"""Utility functions for working with agents."""

import sys
import time
import uuid
from typing import Optional, Any

import signal
import threading
import time
from typing import Optional

from langgraph.prebuilt import create_react_agent
from ra_aid.console.formatting import print_stage_header, print_error
from ra_aid.console.output import print_agent_output
from ra_aid.logging_config import get_logger
from ra_aid.exceptions import AgentInterrupt
from ra_aid.tool_configs import (
    get_implementation_tools,
    get_research_tools,
    get_planning_tools,
    get_web_research_tools
)
from ra_aid.prompts import (
    IMPLEMENTATION_PROMPT,
    EXPERT_PROMPT_SECTION_IMPLEMENTATION,
    HUMAN_PROMPT_SECTION_IMPLEMENTATION,
    EXPERT_PROMPT_SECTION_RESEARCH,
    WEB_RESEARCH_PROMPT_SECTION_RESEARCH,
    WEB_RESEARCH_PROMPT_SECTION_CHAT,
    WEB_RESEARCH_PROMPT_SECTION_PLANNING,
    RESEARCH_PROMPT,
    RESEARCH_ONLY_PROMPT,
    HUMAN_PROMPT_SECTION_RESEARCH,
    PLANNING_PROMPT,
    EXPERT_PROMPT_SECTION_PLANNING,
    WEB_RESEARCH_PROMPT_SECTION_PLANNING,
    HUMAN_PROMPT_SECTION_PLANNING,
    WEB_RESEARCH_PROMPT,
)
from langgraph.checkpoint.memory import MemorySaver

from langchain_core.messages import HumanMessage
from langchain_core.messages import BaseMessage
from anthropic import APIError, APITimeoutError, RateLimitError, InternalServerError
from rich.console import Console
from rich.markdown import Markdown
from rich.panel import Panel

from ra_aid.tools.memory import (
    _global_memory,
    get_memory_value,
    get_related_files,
)
from ra_aid.tool_configs import get_research_tools
from ra_aid.prompts import (
    RESEARCH_PROMPT,
    RESEARCH_ONLY_PROMPT,
    EXPERT_PROMPT_SECTION_RESEARCH,
    HUMAN_PROMPT_SECTION_RESEARCH
)


console = Console()

logger = get_logger(__name__)

def run_research_agent(
    base_task_or_query: str,
    model,
    *,
    expert_enabled: bool = False,
    research_only: bool = False,
    hil: bool = False,
    web_research_enabled: bool = False,
    memory: Optional[Any] = None,
    config: Optional[dict] = None,
    thread_id: Optional[str] = None,
    console_message: Optional[str] = None
) -> Optional[str]:
    """Run a research agent with the given configuration.

    Args:
        base_task_or_query: The main task or query for research
        model: The LLM model to use
        expert_enabled: Whether expert mode is enabled
        research_only: Whether this is a research-only task
        hil: Whether human-in-the-loop mode is enabled
        web_research_enabled: Whether web research is enabled
        memory: Optional memory instance to use
        config: Optional configuration dictionary
        thread_id: Optional thread ID (defaults to new UUID)
        console_message: Optional message to display before running

    Returns:
        Optional[str]: The completion message if task completed successfully

    Example:
        result = run_research_agent(
            "Research Python async patterns",
            model,
            expert_enabled=True,
            research_only=True
        )
    """
    thread_id = thread_id or str(uuid.uuid4())
    logger.debug("Starting research agent with thread_id=%s", thread_id)
    logger.debug("Research configuration: expert=%s, research_only=%s, hil=%s, web=%s",
                expert_enabled, research_only, hil, web_research_enabled)

    # Initialize memory if not provided
    if memory is None:
        memory = MemorySaver()

    # Set up thread ID
    if thread_id is None:
        thread_id = str(uuid.uuid4())

    # Configure tools
    tools = get_research_tools(
        research_only=research_only,
        expert_enabled=expert_enabled,
        human_interaction=hil,
        web_research_enabled=config.get('web_research', False)
    )

    # Create agent
    agent = create_react_agent(model, tools, checkpointer=memory)

    # Format prompt sections
    expert_section = EXPERT_PROMPT_SECTION_RESEARCH if expert_enabled else ""
    human_section = HUMAN_PROMPT_SECTION_RESEARCH if hil else ""
    web_research_section = WEB_RESEARCH_PROMPT_SECTION_RESEARCH if config.get('web_research') else ""

    # Get research context from memory
    key_facts = _global_memory.get("key_facts", "")
    code_snippets = _global_memory.get("code_snippets", "")
    related_files = _global_memory.get("related_files", "")

    # Build prompt
    prompt = (RESEARCH_ONLY_PROMPT if research_only else RESEARCH_PROMPT).format(
        base_task=base_task_or_query,
        research_only_note='' if research_only else ' Only request implementation if the user explicitly asked for changes to be made.',
        expert_section=expert_section,
        human_section=human_section,
        web_research_section=web_research_section,
        key_facts=key_facts,
        code_snippets=code_snippets,
        related_files=related_files
    )

    # Set up configuration
    run_config = {
         "configurable": {"thread_id": thread_id},
        "recursion_limit": 100
    }
    if config:
        run_config.update(config)

    try:
        # Display console message if provided
        if console_message:
            console.print(Panel(Markdown(console_message), title="🔬 Looking into it..."))

        # Run agent with retry logic
        logger.debug("Research agent completed successfully")
        return run_agent_with_retry(agent, prompt, run_config)
    except Exception as e:
        logger.error("Research agent failed: %s", str(e), exc_info=True)
        raise

def run_web_research_agent(
    query: str,
    model,
    *,
    expert_enabled: bool = False,
    hil: bool = False,
    web_research_enabled: bool = False,
    memory: Optional[Any] = None,
    config: Optional[dict] = None,
    thread_id: Optional[str] = None,
    console_message: Optional[str] = None
) -> Optional[str]:
    """Run a web research agent with the given configuration.

    Args:
        query: The mainquery for web research
        model: The LLM model to use
        expert_enabled: Whether expert mode is enabled
        hil: Whether human-in-the-loop mode is enabled
        web_research_enabled: Whether web research is enabled
        memory: Optional memory instance to use
        config: Optional configuration dictionary
        thread_id: Optional thread ID (defaults to new UUID)
        console_message: Optional message to display before running

    Returns:
        Optional[str]: The completion message if task completed successfully

    Example:
        result = run_web_research_agent(
            "Research latest Python async patterns",
            model,
            expert_enabled=True
        )
    """
    thread_id = thread_id or str(uuid.uuid4())
    logger.debug("Starting web research agent with thread_id=%s", thread_id)
    logger.debug("Web research configuration: expert=%s, hil=%s, web=%s",
                expert_enabled, hil, web_research_enabled)

    # Initialize memory if not provided
    if memory is None:
        memory = MemorySaver()

    # Set up thread ID
    if thread_id is None:
        thread_id = str(uuid.uuid4())

    # Configure tools using restricted web research toolset
    tools = get_web_research_tools(expert_enabled=expert_enabled)

    # Create agent
    agent = create_react_agent(model, tools, checkpointer=memory)

    # Format prompt sections
    expert_section = EXPERT_PROMPT_SECTION_RESEARCH if expert_enabled else ""
    human_section = HUMAN_PROMPT_SECTION_RESEARCH if hil else ""

    # Get research context from memory
    key_facts = _global_memory.get("key_facts", "")
    code_snippets = _global_memory.get("code_snippets", "")
    related_files = _global_memory.get("related_files", "")

    # Build prompt
    prompt = WEB_RESEARCH_PROMPT.format(
        web_research_query=query,
        expert_section=expert_section,
        human_section=human_section,
        key_facts=key_facts,
        code_snippets=code_snippets,
        related_files=related_files
    )

    # Set up configuration
    run_config = {
        "configurable": {"thread_id": thread_id},
        "recursion_limit": 100
    }
    if config:
        run_config.update(config)

    try:
        # Display console message if provided
        if console_message:
            console.print(Panel(Markdown(console_message), title="🔍 Starting Web Research..."))

        # Run agent with retry logic
        logger.debug("Web research agent completed successfully")
        return run_agent_with_retry(agent, prompt, run_config)
    except Exception as e:
        logger.error("Web research agent failed: %s", str(e), exc_info=True)
        raise

def run_planning_agent(
    base_task: str,
    model,
    *,
    expert_enabled: bool = False,
    hil: bool = False,
    memory: Optional[Any] = None,
    config: Optional[dict] = None,
    thread_id: Optional[str] = None
) -> Optional[str]:
    """Run a planning agent to create implementation plans.

    Args:
        base_task: The main task to plan implementation for
        model: The LLM model to use
        expert_enabled: Whether expert mode is enabled
        hil: Whether human-in-the-loop mode is enabled
        memory: Optional memory instance to use
        config: Optional configuration dictionary
        thread_id: Optional thread ID (defaults to new UUID)

    Returns:
        Optional[str]: The completion message if planning completed successfully
    """
    thread_id = thread_id or str(uuid.uuid4())
    logger.debug("Starting planning agent with thread_id=%s", thread_id)
    logger.debug("Planning configuration: expert=%s, hil=%s", expert_enabled, hil)

    # Initialize memory if not provided
    if memory is None:
        memory = MemorySaver()

    # Set up thread ID
    if thread_id is None:
        thread_id = str(uuid.uuid4())

    # Configure tools
    tools = get_planning_tools(expert_enabled=expert_enabled, web_research_enabled=config.get('web_research', False))

    # Create agent
    agent = create_react_agent(model, tools, checkpointer=memory)

    # Format prompt sections
    expert_section = EXPERT_PROMPT_SECTION_PLANNING if expert_enabled else ""
    human_section = HUMAN_PROMPT_SECTION_PLANNING if hil else ""
    web_research_section = WEB_RESEARCH_PROMPT_SECTION_PLANNING if config.get('web_research') else ""

    # Build prompt
    planning_prompt = PLANNING_PROMPT.format(
        expert_section=expert_section,
        human_section=human_section,
        web_research_section=web_research_section,
        base_task=base_task,
        research_notes=get_memory_value('research_notes'),
        related_files="\n".join(get_related_files()),
        key_facts=get_memory_value('key_facts'),
        key_snippets=get_memory_value('key_snippets'),
        research_only_note='' if config.get('research_only') else ' Only request implementation if the user explicitly asked for changes to be made.'
    )

    # Set up configuration
    run_config = {
        "configurable": {"thread_id": thread_id},
        "recursion_limit": 100
    }
    if config:
        run_config.update(config)

    try:
        print_stage_header("Planning Stage")
        logger.debug("Planning agent completed successfully")
        return run_agent_with_retry(agent, planning_prompt, run_config)
    except Exception as e:
        logger.error("Planning agent failed: %s", str(e), exc_info=True)
        raise

def run_task_implementation_agent(
    base_task: str,
    tasks: list,
    task: str,
    plan: str,
    related_files: list,
    model,
    *,
    expert_enabled: bool = False,
    web_research_enabled: bool = False,
    memory: Optional[Any] = None,
    config: Optional[dict] = None,
    thread_id: Optional[str] = None
) -> Optional[str]:
    """Run an implementation agent for a specific task.

    Args:
        base_task: The main task being implemented
        tasks: List of tasks to implement
        plan: The implementation plan
        related_files: List of related files
        model: The LLM model to use
        expert_enabled: Whether expert mode is enabled
        web_research_enabled: Whether web research is enabled
        memory: Optional memory instance to use
        config: Optional configuration dictionary
        thread_id: Optional thread ID (defaults to new UUID)

    Returns:
        Optional[str]: The completion message if task completed successfully
    """
    thread_id = thread_id or str(uuid.uuid4())
    logger.debug("Starting implementation agent with thread_id=%s", thread_id)
    logger.debug("Implementation configuration: expert=%s, web=%s", expert_enabled, web_research_enabled)
    logger.debug("Task details: base_task=%s, current_task=%s", base_task, task)
    logger.debug("Related files: %s", related_files)

    # Initialize memory if not provided
    if memory is None:
        memory = MemorySaver()

    # Set up thread ID
    if thread_id is None:
        thread_id = str(uuid.uuid4())

    # Configure tools
    tools = get_implementation_tools(expert_enabled=expert_enabled, web_research_enabled=config.get('web_research', False))

    # Create agent
    agent = create_react_agent(model, tools, checkpointer=memory)

    # Build prompt
    prompt = IMPLEMENTATION_PROMPT.format(
        base_task=base_task,
        task=task,
        tasks=tasks,
        plan=plan,
        related_files=related_files,
        key_facts=get_memory_value('key_facts'),
        key_snippets=get_memory_value('key_snippets'),
        work_log=get_memory_value('work_log'),
        expert_section=EXPERT_PROMPT_SECTION_IMPLEMENTATION if expert_enabled else "",
        human_section=HUMAN_PROMPT_SECTION_IMPLEMENTATION if _global_memory.get('config', {}).get('hil', False) else "",
        web_research_section=WEB_RESEARCH_PROMPT_SECTION_CHAT if config.get('web_research') else ""
    )

    # Set up configuration
    run_config = {
        "configurable": {"thread_id": thread_id},
        "recursion_limit": 100
    }
    if config:
        run_config.update(config)

    try:
        logger.debug("Implementation agent completed successfully")
        return run_agent_with_retry(agent, prompt, run_config)
    except Exception as e:
        logger.error("Implementation agent failed: %s", str(e), exc_info=True)
        raise

_CONTEXT_STACK = []
_INTERRUPT_CONTEXT = None
_FEEDBACK_MODE = False

def _request_interrupt(signum, frame):
    global _INTERRUPT_CONTEXT
    if _CONTEXT_STACK:
        _INTERRUPT_CONTEXT = _CONTEXT_STACK[-1]

    if _FEEDBACK_MODE:
        print()
        print(" 👋 Bye!")
        print()
        sys.exit(0)

class InterruptibleSection:
    def __enter__(self):
        _CONTEXT_STACK.append(self)
        return self

    def __exit__(self, exc_type, exc_value, traceback):
        _CONTEXT_STACK.remove(self)

def check_interrupt():
    if _CONTEXT_STACK and _INTERRUPT_CONTEXT is _CONTEXT_STACK[-1]:
        raise AgentInterrupt("Interrupt requested")

def run_agent_with_retry(agent, prompt: str, config: dict) -> Optional[str]:
    """Run an agent with retry logic for API errors."""
    logger.debug("Running agent with prompt length: %d", len(prompt))
    original_handler = None
    if threading.current_thread() is threading.main_thread():
        original_handler = signal.getsignal(signal.SIGINT)
        signal.signal(signal.SIGINT, _request_interrupt)

    max_retries = 20
    base_delay = 1

    with InterruptibleSection():
        try:
            # Track agent execution depth
            current_depth = _global_memory.get('agent_depth', 0)
            _global_memory['agent_depth'] = current_depth + 1

            for attempt in range(max_retries):
                logger.debug("Attempt %d/%d", attempt + 1, max_retries)
                check_interrupt()
                try:
                    for chunk in agent.stream({"messages": [HumanMessage(content=prompt)]}, config):
                        logger.debug("Agent output: %s", chunk)
                        check_interrupt()
                        print_agent_output(chunk)
                        logger.debug("Agent run completed successfully")
                    return "Agent run completed successfully"
                except (KeyboardInterrupt, AgentInterrupt):
                    raise
                except (InternalServerError, APITimeoutError, RateLimitError, APIError) as e:
                    if attempt == max_retries - 1:
                        logger.error("Max retries reached, failing: %s", str(e))
                        raise RuntimeError(f"Max retries ({max_retries}) exceeded. Last error: {e}")
                    logger.warning("API error (attempt %d/%d): %s", attempt + 1, max_retries, str(e))
                    delay = base_delay * (2 ** attempt)
                    print_error(f"Encountered {e.__class__.__name__}: {e}. Retrying in {delay}s... (Attempt {attempt+1}/{max_retries})")
                    start = time.monotonic()
                    while time.monotonic() - start < delay:
                        check_interrupt()
                        time.sleep(0.1)
        finally:
            # Reset depth tracking
            _global_memory['agent_depth'] = _global_memory.get('agent_depth', 1) - 1

            if original_handler and threading.current_thread() is threading.main_thread():
                signal.signal(signal.SIGINT, original_handler)
