import argparse
import sys
from rich.panel import Panel
from rich.console import Console
from langchain_core.messages import HumanMessage
from langgraph.checkpoint.memory import MemorySaver
from langgraph.prebuilt import create_react_agent
from ra_aid.tools import (
    ask_expert, run_shell_command, run_programming_task,
    emit_research_notes, emit_plan, emit_related_files, emit_task,
    emit_expert_context, get_memory_value, emit_key_facts, delete_key_facts,
    emit_key_snippets, delete_key_snippets,
    emit_research_subtask, request_implementation, read_file_tool, fuzzy_find_project_files, ripgrep_search, list_directory_tree,
    swap_task_order
)
from ra_aid.env import validate_environment
from ra_aid.tools.memory import _global_memory, get_related_files, one_shot_completed
from ra_aid import print_agent_output, print_stage_header, print_task_header, print_error
from ra_aid.prompts import (
    RESEARCH_PROMPT,
    PLANNING_PROMPT,
    IMPLEMENTATION_PROMPT,
)
from ra_aid.exceptions import TaskCompletedException
import time
from anthropic import APIError, APITimeoutError, RateLimitError, InternalServerError
from ra_aid.llm import initialize_llm

# Read-only tools that don't modify system state
READ_ONLY_TOOLS = [
    emit_related_files,
    emit_key_facts,
    delete_key_facts,
    emit_key_snippets,
    delete_key_snippets,
    read_file_tool,
    fuzzy_find_project_files,
    ripgrep_search,
    run_shell_command # can modify files, but we still need it for read-only tasks.
]

# Tools that can modify files or system state
MODIFICATION_TOOLS = [
    run_programming_task
]

# Common tools used across multiple agents
COMMON_TOOLS = READ_ONLY_TOOLS + []

# Expert-specific tools
EXPERT_TOOLS = [
    emit_expert_context,
    ask_expert
]

# Research-specific tools
RESEARCH_TOOLS = [
    list_directory_tree,
    emit_research_subtask,
    run_shell_command,
    emit_research_notes,
    one_shot_completed
]

def parse_arguments():
    parser = argparse.ArgumentParser(
        description='RA.Aid - AI Agent for executing programming and research tasks',
        formatter_class=argparse.RawDescriptionHelpFormatter,
        epilog='''
Examples:
    ra-aid -m "Add error handling to the database module"
    ra-aid -m "Explain the authentication flow" --research-only
        '''
    )
    parser.add_argument(
        '-m', '--message',
        type=str,
        help='The task or query to be executed by the agent'
    )
    parser.add_argument(
        '--research-only',
        action='store_true',
        help='Only perform research without implementation'
    )
    parser.add_argument(
        '--provider',
        type=str,
        default='anthropic',
        choices=['anthropic', 'openai', 'openrouter', 'openai-compatible'],
        help='The LLM provider to use'
    )
    parser.add_argument(
        '--model',
        type=str,
        help='The model name to use (required for non-Anthropic providers)'
    )
    parser.add_argument(
        '--cowboy-mode',
        action='store_true',
        help='Skip interactive approval for shell commands'
    )
    parser.add_argument(
        '--expert-provider',
        type=str,
        default='openai',
        choices=['anthropic', 'openai', 'openrouter', 'openai-compatible'],
        help='The LLM provider to use for expert knowledge queries (default: openai)'
    )
    parser.add_argument(
        '--expert-model',
        type=str,
        help='The model name to use for expert knowledge queries (required for non-OpenAI providers)'
    )
    
    args = parser.parse_args()
    
    # Set default model for Anthropic, require model for other providers
    if args.provider == 'anthropic':
        if not args.model:
            args.model = 'claude-3-5-sonnet-20241022'
    elif not args.model:
        parser.error(f"--model is required when using provider '{args.provider}'")
    
    # Validate expert model requirement
    if args.expert_provider != 'openai' and not args.expert_model:
        parser.error(f"--expert-model is required when using expert provider '{args.expert_provider}'")
    
    return args

# Create console instance
console = Console()

# Create individual memory objects for each agent
research_memory = MemorySaver()
planning_memory = MemorySaver()
implementation_memory = MemorySaver()

def get_research_tools(research_only: bool = False, expert_enabled: bool = True) -> list:
    """Get the list of research tools based on mode and whether expert is enabled."""
    # Start with read-only tools
    tools = READ_ONLY_TOOLS.copy()
    
    # Add research tools except run_shell_command
    research_tools = [t for t in RESEARCH_TOOLS if t != run_shell_command]
    tools.extend(research_tools)
    
    # Add modification tools if not research_only
    if not research_only:
        tools.extend(MODIFICATION_TOOLS)
        tools.append(request_implementation)
    
    # Add expert tools if enabled
    if expert_enabled:
        tools.extend(EXPERT_TOOLS)
    
    return tools

def get_planning_tools(expert_enabled: bool = True) -> list:
    """Get the list of planning tools based on whether expert is enabled."""
    # Start with common tools
    tools = COMMON_TOOLS.copy()
    
    # Add planning-specific tools
    planning_tools = [
        emit_plan,
        emit_task, 
        swap_task_order
    ]
    tools.extend(planning_tools)
    
    # Add expert tools if enabled
    if expert_enabled:
        tools.extend(EXPERT_TOOLS)
    
    return tools

def get_implementation_tools(expert_enabled: bool = True) -> list:
    """Get the list of implementation tools based on whether expert is enabled."""
    # Start with common tools
    tools = COMMON_TOOLS.copy()
    
    # Add modification tools since it's not research-only
    tools.extend(MODIFICATION_TOOLS)
    
    # Add expert tools if enabled
    if expert_enabled:
        tools.extend(EXPERT_TOOLS)
    
    return tools

def is_informational_query() -> bool:
    """Determine if the current query is informational based on implementation_requested state."""
    return _global_memory.get('config', {}).get('research_only', False) or not is_stage_requested('implementation')

def is_stage_requested(stage: str) -> bool:
    """Check if a stage has been requested to proceed."""
    if stage == 'implementation':
        return len(_global_memory.get('implementation_requested', [])) > 0
    return False

def run_agent_with_retry(agent, prompt: str, config: dict):
    """Run an agent with retry logic for internal server errors."""
    max_retries = 20
    base_delay = 1  # Initial delay in seconds
    
    for attempt in range(max_retries):
        try:
            for chunk in agent.stream(
                {"messages": [HumanMessage(content=prompt)]},
                config
            ):
                print_agent_output(chunk)
            break
        except (InternalServerError, APITimeoutError, RateLimitError, APIError) as e:
            if attempt == max_retries - 1:
                raise RuntimeError(f"Max retries ({max_retries}) exceeded. Last error: {str(e)}")
            
            delay = base_delay * (2 ** attempt)  # Exponential backoff
            error_type = e.__class__.__name__
            print_error(f"Encountered {error_type}: {str(e)}. Retrying in {delay} seconds... (Attempt {attempt + 1}/{max_retries})")
            time.sleep(delay)
            continue

def run_implementation_stage(base_task, tasks, plan, related_files, model, expert_enabled: bool):
    """Run implementation stage with a distinct agent for each task."""
    if not is_stage_requested('implementation'):
        print_stage_header("Implementation Stage Skipped")
        return
        
    print_stage_header("Implementation Stage")
    
    # Get tasks directly from memory, maintaining order by ID
    task_list = [task for _, task in sorted(_global_memory['tasks'].items())]
    
    print_task_header(f"Found {len(task_list)} tasks to implement")
    
    for i, task in enumerate(task_list, 1):
        print_task_header(task)
        
        # Create a unique memory instance for this task
        task_memory = MemorySaver()
        
        # Create a fresh agent for each task
        task_agent = create_react_agent(model, get_implementation_tools(expert_enabled=expert_enabled), checkpointer=task_memory)
        
        # Construct task-specific prompt
        task_prompt = IMPLEMENTATION_PROMPT.format(
            plan=plan,
            key_facts=get_memory_value('key_facts'),
            key_snippets=get_memory_value('key_snippets'),
            task=task,
            related_files="\n".join(related_files),
            base_task=base_task
        )
        
        # Run agent for this task
        run_agent_with_retry(task_agent, task_prompt, {"configurable": {"thread_id": "abc123"}, "recursion_limit": 100})


def run_research_subtasks(base_task: str, config: dict, model, expert_enabled: bool):
    """Run research subtasks with separate agents."""
    subtasks = _global_memory.get('research_subtasks', [])
    if not subtasks:
        return
        
    print_stage_header("Research Subtasks")
    
    # Get tools for subtask agents (excluding emit_research_subtask and implementation)
    research_only = _global_memory.get('config', {}).get('research_only', False)
    subtask_tools = [
        t for t in get_research_tools(research_only=research_only, expert_enabled=expert_enabled)
        if t.name not in ['emit_research_subtask']
    ]
    
    for i, subtask in enumerate(subtasks, 1):
        print_task_header(f"Research Subtask {i}/{len(subtasks)}")
        
        # Create fresh memory and agent for each subtask
        subtask_memory = MemorySaver()
        subtask_agent = create_react_agent(
            model,
            subtask_tools,
            checkpointer=subtask_memory
        )
        
        # Run the subtask agent
        subtask_prompt = f"Base Task: {base_task}\nResearch Subtask: {subtask}\n\n{RESEARCH_PROMPT}"
        run_agent_with_retry(subtask_agent, subtask_prompt, config)



def main():
    """Main entry point for the ra-aid command line tool."""
    try:
        try:
            args = parse_arguments()
            expert_enabled, expert_missing = validate_environment(args)  # Will exit if main env vars missing
            
            if expert_missing:
                console.print(Panel(
                    f"[yellow]Expert tools disabled due to missing configuration:[/yellow]\n" + 
                    "\n".join(f"- {m}" for m in expert_missing) +
                    "\nSet the required environment variables or args to enable expert mode.",
                    title="Expert Tools Disabled",
                    style="yellow"
                ))
            
            # Create the base model after validation
            model = initialize_llm(args.provider, args.model)

            # Validate message is provided
            if not args.message:
                print_error("--message is required")
                sys.exit(1)
                
            base_task = args.message
            config = {
                "configurable": {
                    "thread_id": "abc123"
                },
                "recursion_limit": 100,
                "research_only": args.research_only,
                "cowboy_mode": args.cowboy_mode
            }
            
            # Store config in global memory for access by is_informational_query
            _global_memory['config'] = config
            
            # Store expert provider and model in config
            _global_memory['config']['expert_provider'] = args.expert_provider
            _global_memory['config']['expert_model'] = args.expert_model
            
            # Run research stage
            print_stage_header("Research Stage")
            
            # Create research agent
            research_agent = create_react_agent(
                model,
                get_research_tools(research_only=_global_memory.get('config', {}).get('research_only', False), expert_enabled=expert_enabled),
                checkpointer=research_memory
            )
            
            research_prompt = f"""User query: {base_task} --keep it simple

{RESEARCH_PROMPT}

Be very thorough in your research and emit lots of snippets, key facts. If you take more than a few steps, be eager to emit research subtasks.{'' if args.research_only else ' Only request implementation if the user explicitly asked for changes to be made.'}"""

            try:
                run_agent_with_retry(research_agent, research_prompt, config)
            except TaskCompletedException as e:
                print_stage_header("Task Completed")
                raise  # Re-raise to be caught by outer handler

            # Run any research subtasks
            run_research_subtasks(base_task, config, model, expert_enabled=expert_enabled)
            
            # Proceed with planning and implementation if not an informational query
            if not is_informational_query():
                print_stage_header("Planning Stage")
                
                # Create planning agent
                planning_agent = create_react_agent(model, get_planning_tools(expert_enabled=expert_enabled), checkpointer=planning_memory)
                
                planning_prompt = PLANNING_PROMPT.format(
                    research_notes=get_memory_value('research_notes'),
                    key_facts=get_memory_value('key_facts'),
                    key_snippets=get_memory_value('key_snippets'),
                    base_task=base_task,
                    related_files="\n".join(get_related_files())
                )

                # Run planning agent
                run_agent_with_retry(planning_agent, planning_prompt, config)

                # Run implementation stage with task-specific agents
                run_implementation_stage(
                    base_task,
                    get_memory_value('tasks'),
                    get_memory_value('plan'),
                    get_related_files(),
                    model,
                    expert_enabled=expert_enabled
                )
        except TaskCompletedException:
            console.print(Panel(
                "[green]Task was completed successfully as a one-shot operation.[/green]",
                title="Task Completed",
                style="green"
            ))
            sys.exit(0)
    finally:
        pass

if __name__ == "__main__":
    main()
