import os
import time
import logging
import json
import ast
import contextlib
from rich.console import Console
from rich.panel import Panel

from templates import agent_template

logger = logging.getLogger(__name__)
console = Console()


def init_trace_file(debug, log_dir="logs"):
    """
    Creates the log directory and returns a unique filepath 
    based on the current timestamp.
    """
    if not os.path.exists(log_dir):
        os.makedirs(log_dir)
    
    timestamp = time.strftime("%Y%m%d-%H%M%S")
    filename = os.path.join(log_dir, f"trace_{timestamp}.json")
    if debug: logger.debug(f"Trace logging initialized: {filename}")
    return filename

def save_agent_trace(filepath, messages, full_history=None):
    """
    Dumps the current state of the conversation to a JSON file.
    Overwrites the file each step so the last write is always the complete history.
    """
    try:
        data_to_save = {
            "timestamp": time.time(),
            # If you are using history compression, 'messages' might get cut.
            # If you want the RAW full history, pass full_history. 
            # Otherwise, we log what the agent currently 'sees'.
            "context_window": messages 
        }
        
        with open(filepath, 'w', encoding='utf-8') as f:
            json.dump(data_to_save, f, indent=2, ensure_ascii=False)
            
    except Exception as e:
        logger.error(f"Failed to save trace file: {e}")

def build_chat_prompt(messages):
    prompt = ""
    for msg in messages:
        role = msg.get("role")
        content = msg.get("content")
        prompt += f"{agent_template.IM_START}{role}\n{content}{agent_template.IM_END}\n"
    prompt += f"{agent_template.IM_START}{agent_template.ROLE_ASSISTANT}" # Removed trailing newline
    return prompt


def _analyze_code_safety(code_str):
    """
    Returns: (is_safe: bool, error_msg: str, line_number: int | None)
    """
    try:
        tree = ast.parse(code_str)
    except SyntaxError as e:
        # e.lineno is the line where the parser failed
        return False, f"SyntaxError: {e.msg}", e.lineno

    tainted_vars = {"RAW_CORPUS"}
    has_print = False

    for node in ast.walk(tree):
        # 1. Track assignments
        if isinstance(node, ast.Assign):
            if isinstance(node.value, ast.Name) and node.value.id in tainted_vars:
                for target in node.targets:
                    if isinstance(target, ast.Name):
                        tainted_vars.add(target.id)

        # 2. Check Call nodes
        if isinstance(node, ast.Call):
            if isinstance(node.func, ast.Name) and node.func.id == 'print':
                has_print = True
                for arg in node.args:
                    if isinstance(arg, ast.Name) and arg.id in tainted_vars:
                        return False, f"Safety Violation: Printing '{arg.id}' (RAW_CORPUS). Use slicing.", node.lineno
            
            # Check re.compile arguments
            is_re_compile = False
            if isinstance(node.func, ast.Attribute) and node.func.attr == 'compile':
                is_re_compile = True
            elif isinstance(node.func, ast.Name) and node.func.id == 'compile':
                is_re_compile = True

            if is_re_compile and len(node.args) > 2:
                return False, "Library Usage Error: `re.compile` accepts max 2 args.", node.lineno

    # 3. Global Check (No specific line number)
    if not has_print:
        return False, "Observability Error: No `print()` statements found.", None
    
    return True, None, None

def _extract_context_block(code_str, target_lineno):
    """
    Extracts lines surrounding target_lineno bounded by empty lines.
    Returns: (start_index, end_index, snippet_str)
    """
    lines = code_str.split('\n')
    # target_lineno is 1-based, list is 0-based
    idx = target_lineno - 1
    
    # Clamp index just in case
    if idx < 0: idx = 0
    if idx >= len(lines): idx = len(lines) - 1

    start_idx = idx
    end_idx = idx

    # Scan Up
    while start_idx > 0:
        if lines[start_idx - 1].strip() == "":
            break
        start_idx -= 1
    
    # Scan Down
    while end_idx < len(lines) - 1:
        if lines[end_idx + 1].strip() == "":
            break
        end_idx += 1
    
    # Extract the block including the found boundaries (or lack thereof)
    snippet_lines = lines[start_idx : end_idx + 1]
    return start_idx, end_idx, "\n".join(snippet_lines)

def safeguard_and_repair(debug, client, messages, schema, original_code):
    is_safe, error_msg, line_no = _analyze_code_safety(original_code)
    
    if is_safe:
        return original_code

    if debug: 
        logger.warning(f"Safeguard triggered: {error_msg} (Line: {line_no})")
        console.print(Panel(f"{error_msg}", title="Safeguard Interrupt", style="bold red"))

        console.print(Panel(
                f"[italic]{thought}[/italic]",
                title="Unsafe Code",
                title_align="left",
                border_style="hot_pink2"
            ))

    # STRATEGY 1: SNIPPET REPAIR (Optimization)
    # If we have a specific line number, we only send that block.
    if line_no is not None:
        start_idx, end_idx, snippet = _extract_context_block(original_code, line_no)
        
        # We create a temporary "micro-agent" prompt just for fixing the snippet
        # We reuse the schema to ensure we get a clean content block back
        repair_prompt = [
            {"role": "system", "content": "You are a code repair assistant. Output only the fixed code snippet in the JSON content field."},
            {"role": "user", "content": (
                f"The following Python code snippet failed validation.\n"
                f"Error: {error_msg} (occurred around line {line_no})\n\n"
                f"```python\n{snippet}\n```\n\n"
                f"Return the JSON with the fixed snippet. "
                f"Maintain original indentation. Add a comment (# FIXED) to changed lines."
            )}
        ]
        if debug:
            console.print(Panel(f"{snippet}", title="Attempting Snippet Repair", style="light_goldenrod1"))
        
        response_text = client.completion(repair_prompt, schema=schema, temperature=0.0)
        
        try:
            response_json = json.loads(response_text)
            fixed_snippet = response_json.get("content", "")
            
            if debug:
                console.print(Panel(f"{fixed_snippet}", title="Repaired Snippet", style="yellow1"))
            
            # Stitch the code back together
            all_lines = original_code.split('\n')
            # We replace the range we extracted with the new snippet
            # Note: fixed_snippet might have different line count, that's fine.
            
            pre_block = all_lines[:start_idx]
            post_block = all_lines[end_idx + 1:]
            
            # Reassemble
            full_fixed_code = "\n".join(pre_block + [fixed_snippet] + post_block)
            
            return full_fixed_code

        except json.JSONDecodeError:
            # If the snippet repair fails to parse, fall through to full repair
            if debug: logger.error("Snippet repair failed to parse. Falling back to full repair.")
            pass

    # STRATEGY 2: FULL REPAIR (Fallback)
    # Used for global errors (missing prints) or if snippet repair crashed
    repair_messages = messages + [
        {"role": agent_template.ROLE_ASSISTANT, "content": json.dumps({
            "thought": "Drafting code...", 
            "action": "execute_python", 
            "content": original_code
        })},
        {"role": agent_template.ROLE_USER, "content": (
            f"SYSTEM INTERRUPT: Your code failed pre-flight safety checks.\n"
            f"Error: {error_msg}\n\n"
            f"Generate the JSON response again with CORRECTED Python code.\n"
            f"IMPORTANT: You must add a comment (# FIXED: ...) to the corrected line."
        )}
    ]

    response_text = client.completion(build_chat_prompt(repair_messages), schema=schema, temperature=0.0)

    try:
        response_json = json.loads(response_text)
        return response_json.get("content", "")
    except json.JSONDecodeError:
        return ""

def compress_history(debug, client, messages, keep_last_pairs=2):
    """
    Compresses the middle of the conversation history.
    Preserves: System Prompt (0), User Task (1), and the last N pairs of interaction.
    """
    # Calculate how many messages to keep at the end (pairs * 2)
    keep_count = keep_last_pairs * 2
    
    # Check if we actually have enough history to compress
    # We need: System + Task + (At least 2 messages to compress) + Keep_Count
    if len(messages) < (2 + 2 + keep_count):
        if debug: logger.warning("History too short to compress, but context is full. Crashing safely.")
        return messages # Nothing we can do, let it fail or truncate manually

    # Define the slice to compress
    # Start at 2 (after Task), End at -keep_count
    to_compress = messages[2:-keep_count]
    
    # 1. format the text for the summarizer
    history_text = ""
    for msg in to_compress:
        role = msg['role'].upper()
        content = msg['content']
        history_text += f"[{role}]: {content}\n"

    # 2. Build the summarization prompt
    summary_prompt = (
        "You are a technical documentation assistant. "
        "Summarize the following interaction history between an AI Agent and a System. "
        "Focus on: 1. Code executed, 2. Errors encountered, 3. Specific data/variables discovered. "
        "Be concise. Do not chat.\n\n"
        f"--- HISTORY START ---\n{history_text}\n--- HISTORY END ---"
    )
    
    if debug: logger.debug(f"Compressing {len(to_compress)} messages...")
    
    # 3. Call the LLM (We use the Agent Client for high-quality summaries)
    # We use a simple generation call here.
    summary_text = client.completion(
        build_chat_prompt([{"role": "user", "content": summary_prompt}])
    )
    
    # 4. Create the new compressed message
    summary_message = {
        "role": "user", 
        "content": f"[SYSTEM SUMMARY OF PREVIOUS ACTIONS]\n{summary_text}"
    }
    
    # 5. Reconstruct the list
    new_messages = [messages[0], messages[1]] + [summary_message] + messages[-keep_count:]
    
    if debug: logger.info(f"Compression complete. Reduced {len(messages)} msgs to {len(new_messages)}.")
    return new_messages

def generate_final_report(debug, client, task_text, raw_answer):
    """
    Converts the Agent's raw (likely structured/technical) answer into 
    a natural language response for the user.
    """
    system_prompt = (
"You are a professional report writer. "
"Your goal is to convert the provided Raw Data into a clear, concise, "
"and well-formatted response to the User's original request. "
"Do not add new facts. Just format and explain the existing data."
    )
    
    user_prompt = f"""### USER REQUEST
{task_text}

### RAW DATA COLLECTED
{raw_answer}

### INSTRUCTION
Write the final response in natural language (Markdown).
    """
    
    if debug: logger.debug("Generating natural language report...")
    return client.completion(build_chat_prompt([
        {"role": agent_template.ROLE_SYSTEM, "content": system_prompt},
        {"role": agent_template.ROLE_USER, "content": user_prompt}
    ]))

def load_file(filepath):
    try:
        with open(filepath, 'r', encoding='utf-8') as f:
            return f.read()
    except FileNotFoundError:
        logger.error(f"File not found: {filepath}")
        sys.exit(1)