import os
import re
import logging
import textwrap
import autopep8
import gradio as gr
from huggingface_hub import hf_hub_download
from llama_cpp import Llama
import jwt
from typing import Generator

# Set up logging
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

# JWT settings
JWT_SECRET = os.environ.get("JWT_SECRET")
JWT_ALGORITHM = "HS256"

# Model settings
MODEL_NAME = "leetmonkey_peft__q8_0.gguf"
REPO_ID = "sugiv/leetmonkey-peft-gguf"

# Generation parameters
generation_kwargs = {
    "max_tokens": 2048,
    "stop": ["```", "### Instruction:", "### Response:"],
    "echo": False,
    "temperature": 0.2,
    "top_k": 50,
    "top_p": 0.95,
    "repeat_penalty": 1.1
}

def download_model(model_name: str) -> str:
    logger.info(f"Downloading model: {model_name}")
    model_path = hf_hub_download(
        repo_id=REPO_ID,
        filename=model_name,
        cache_dir="./models",
        force_download=True,
        resume_download=True
    )
    logger.info(f"Model downloaded: {model_path}")
    return model_path

# Download and load the 8-bit model at startup
model_path = download_model(MODEL_NAME)
llm = Llama(
    model_path=model_path,
    n_ctx=2048,
    n_threads=4,
    n_gpu_layers=-1,  # Use all available GPU layers
    verbose=False
)
logger.info("8-bit model loaded successfully")

def generate_solution(instruction: str) -> str:
    system_prompt = "You are a Python coding assistant specialized in solving LeetCode problems. Provide only the complete implementation of the given function. Ensure proper indentation and formatting. Do not include any explanations or multiple solutions."
    full_prompt = f"""### Instruction:
{system_prompt}

Implement the following function for the LeetCode problem:

{instruction}

### Response:
Here's the complete Python function implementation:

```python
"""
    
    response = llm(full_prompt, **generation_kwargs)
    return response["choices"][0]["text"]

def extract_and_format_code(text: str) -> str:
    # Extract code between triple backticks
    code_match = re.search(r'```python\s*(.*?)\s*```', text, re.DOTALL)
    if code_match:
        code = code_match.group(1)
    else:
        code = text

    # Remove any text before the function definition
    code = re.sub(r'^.*?(?=def\s+\w+\s*\()', '', code, flags=re.DOTALL)

    # Dedent the code to remove any common leading whitespace
    code = textwrap.dedent(code)

    # Split the code into lines
    lines = code.split('\n')

    # Find the function definition line
    func_def_index = next((i for i, line in enumerate(lines) if line.strip().startswith('def ')), 0)

    # Ensure proper indentation
    indented_lines = [lines[func_def_index]]  # Keep the function definition as is
    for line in lines[func_def_index + 1:]:
        if line.strip():  # If the line is not empty
            indented_lines.append('    ' + line)  # Add 4 spaces of indentation
        else:
            indented_lines.append(line)  # Keep empty lines as is

    formatted_code = '\n'.join(indented_lines)

    try:
        return autopep8.fix_code(formatted_code)
    except:
        return formatted_code

def verify_token(token: str) -> bool:
    try:
        jwt.decode(token, JWT_SECRET, algorithms=[JWT_ALGORITHM])
        return True
    except jwt.PyJWTError:
        return False

def generate_solution_api(instruction: str, token: str) -> str:
    if not verify_token(token):
        return "Invalid token. Please provide a valid JWT token."
    
    logger.info("Generating solution")
    generated_output = generate_solution(instruction)
    formatted_code = extract_and_format_code(generated_output)
    logger.info("Solution generated successfully")
    return formatted_code

def stream_solution_api(instruction: str, token: str) -> Generator[str, None, None]:
    if not verify_token(token):
        yield "Invalid token. Please provide a valid JWT token."
        return

    logger.info("Streaming solution")
    system_prompt = "You are a Python coding assistant specialized in solving LeetCode problems. Provide only the complete implementation of the given function. Ensure proper indentation and formatting. Do not include any explanations or multiple solutions."
    full_prompt = f"""### Instruction:
{system_prompt}

Implement the following function for the LeetCode problem:

{instruction}

### Response:
Here's the complete Python function implementation:

```python
"""
    
    generated_text = ""
    for chunk in llm(full_prompt, stream=True, **generation_kwargs):
        token = chunk["choices"]["text"]
        generated_text += token
        yield generated_text
    
    formatted_code = extract_and_format_code(generated_text)
    logger.info("Solution generated successfully")
    yield formatted_code

# Gradio interface
def gradio_generate(instruction: str, token: str) -> str:
    return generate_solution_api(instruction, token)

def gradio_stream(instruction: str, token: str) -> str:
    return "".join(list(stream_solution_api(instruction, token)))

iface = gr.Interface(
    fn=[gradio_generate, gradio_stream],
    inputs=[
        gr.Textbox(label="LeetCode Problem Instruction"),
        gr.Textbox(label="JWT Token")
    ],
    outputs=[
        gr.Code(label="Generated Solution"),
        gr.Code(label="Streamed Solution")
    ],
    title="LeetCode Problem Solver",
    description="Enter a LeetCode problem instruction and your JWT token to generate a solution."
)

if __name__ == "__main__":
    iface.launch(share=True)