from datetime import datetime, timezone, timedelta
from typing import Dict, Any, Optional, List
import json
import os
from pathlib import Path
import logging
import aiohttp
import asyncio
import time
from huggingface_hub import HfApi, CommitOperationAdd
from huggingface_hub.utils import build_hf_headers
from datasets import disable_progress_bar
import sys
import contextlib
from concurrent.futures import ThreadPoolExecutor
import tempfile

from app.config import (
    QUEUE_REPO,
    HF_TOKEN,
    EVAL_REQUESTS_PATH
)
from app.config.hf_config import HF_ORGANIZATION
from app.services.hf_service import HuggingFaceService
from app.utils.model_validation import ModelValidator
from app.services.votes import VoteService
from app.core.cache import cache_config
from app.core.formatting import LogFormatter

# Disable datasets progress bars globally
disable_progress_bar()

logger = logging.getLogger(__name__)

# Context manager to temporarily disable stdout and stderr
@contextlib.contextmanager
def suppress_output():
    stdout = sys.stdout
    stderr = sys.stderr
    devnull = open(os.devnull, 'w')
    try:
        sys.stdout = devnull
        sys.stderr = devnull
        yield
    finally:
        sys.stdout = stdout
        sys.stderr = stderr
        devnull.close()

class ProgressTracker:
    def __init__(self, total: int, desc: str = "Progress", update_frequency: int = 10):
        self.total = total
        self.current = 0
        self.desc = desc
        self.start_time = time.time()
        self.update_frequency = update_frequency  # Percentage steps
        self.last_update = -1
        
        # Initial log with fancy formatting
        logger.info(LogFormatter.section(desc))
        logger.info(LogFormatter.info(f"Starting processing of {total:,} items..."))
        sys.stdout.flush()
    
    def update(self, n: int = 1):
        self.current += n
        current_percentage = (self.current * 100) // self.total
        
        # Only update on frequency steps (e.g., 0%, 10%, 20%, etc.)
        if current_percentage >= self.last_update + self.update_frequency or current_percentage == 100:
            elapsed = time.time() - self.start_time
            rate = self.current / elapsed if elapsed > 0 else 0
            remaining = (self.total - self.current) / rate if rate > 0 else 0
            
            # Create progress stats
            stats = {
                "Progress": LogFormatter.progress_bar(self.current, self.total),
                "Items": f"{self.current:,}/{self.total:,}",
                "Time": f"⏱️  {elapsed:.1f}s elapsed, {remaining:.1f}s remaining",
                "Rate": f"🚀 {rate:.1f} items/s"
            }
            
            # Log progress using tree format
            for line in LogFormatter.tree(stats):
                logger.info(line)
            sys.stdout.flush()
            
            self.last_update = (current_percentage // self.update_frequency) * self.update_frequency
    
    def close(self):
        elapsed = time.time() - self.start_time
        rate = self.total / elapsed if elapsed > 0 else 0
        
        # Final summary with fancy formatting
        logger.info(LogFormatter.section("COMPLETED"))
        stats = {
            "Total": f"{self.total:,} items",
            "Time": f"{elapsed:.1f}s",
            "Rate": f"{rate:.1f} items/s"
        }
        for line in LogFormatter.stats(stats):
            logger.info(line)
        logger.info("="*50)
        sys.stdout.flush()

class ModelService(HuggingFaceService):
    _instance: Optional['ModelService'] = None
    _initialized = False
    
    def __new__(cls):
        if cls._instance is None:
            logger.info(LogFormatter.info("Creating new ModelService instance"))
            cls._instance = super(ModelService, cls).__new__(cls)
        return cls._instance

    def __init__(self):
        if not hasattr(self, '_init_done'):
            logger.info(LogFormatter.section("MODEL SERVICE INITIALIZATION"))
            super().__init__()
            self.validator = ModelValidator()
            self.vote_service = VoteService()
            self.eval_requests_path = cache_config.eval_requests_file
            logger.info(LogFormatter.info(f"Using eval requests path: {self.eval_requests_path}"))
            
            self.eval_requests_path.parent.mkdir(parents=True, exist_ok=True)
            self.hf_api = HfApi(token=HF_TOKEN)
            self.cached_models = None
            self.last_cache_update = 0
            self.cache_ttl = cache_config.cache_ttl.total_seconds()
            self._init_done = True
            logger.info(LogFormatter.success("Initialization complete"))

    async def _download_and_process_file(self, file: str, session: aiohttp.ClientSession, progress: ProgressTracker) -> Optional[Dict]:
        """Download and process a file asynchronously"""
        try:
            # Build file URL
            url = f"https://huggingface.co/datasets/{QUEUE_REPO}/resolve/main/{file}"
            headers = build_hf_headers(token=self.token)
            
            # Download file
            async with session.get(url, headers=headers) as response:
                if response.status != 200:
                    logger.error(LogFormatter.error(f"Failed to download {file}", f"HTTP {response.status}"))
                    progress.update()
                    return None
                
                try:
                    # First read content as text
                    text_content = await response.text()
                    # Then parse JSON
                    content = json.loads(text_content)
                except json.JSONDecodeError as e:
                    logger.error(LogFormatter.error(f"Failed to decode JSON from {file}", e))
                    progress.update()
                    return None
                
            # Get status and determine target status
            status = content.get("status", "PENDING").upper()
            target_status = None
            status_map = {
                "PENDING": ["PENDING"],
                "EVALUATING": ["RUNNING"],
                "FINISHED": ["FINISHED"]
            }
            
            for target, source_statuses in status_map.items():
                if status in source_statuses:
                    target_status = target
                    break
                    
            if not target_status:
                progress.update()
                return None
                
            # Calculate wait time
            try:
                submit_time = datetime.fromisoformat(content["submitted_time"].replace("Z", "+00:00"))
                if submit_time.tzinfo is None:
                    submit_time = submit_time.replace(tzinfo=timezone.utc)
                current_time = datetime.now(timezone.utc)
                wait_time = current_time - submit_time
                
                model_info = {
                    "name": content["model"],
                    "submitter": content.get("sender", "Unknown"),
                    "revision": content["revision"],
                    "wait_time": f"{wait_time.total_seconds():.1f}s",
                    "submission_time": content["submitted_time"],
                    "status": target_status,
                    "precision": content.get("precision", "Unknown")
                }
                
                progress.update()
                return model_info
                    
            except (ValueError, TypeError) as e:
                logger.error(LogFormatter.error(f"Failed to process {file}", e))
                progress.update()
                return None
                
        except Exception as e:
            logger.error(LogFormatter.error(f"Failed to load {file}", e))
            progress.update()
            return None

    async def _refresh_models_cache(self):
        """Refresh the models cache"""
        try:
            logger.info(LogFormatter.section("CACHE REFRESH"))
            self._log_repo_operation("read", f"{HF_ORGANIZATION}/requests", "Refreshing models cache")
            
            # Initialize models dictionary
            models = {
                "finished": [],
                "evaluating": [],
                "pending": []
            }
            
            try:
                logger.info(LogFormatter.subsection("DATASET LOADING"))
                logger.info(LogFormatter.info("Loading dataset..."))
                
                # Download entire dataset snapshot
                with suppress_output():
                    local_dir = self.hf_api.snapshot_download(
                        repo_id=QUEUE_REPO,
                        repo_type="dataset",
                        token=self.token
                    )
                
                # List JSON files in local directory
                local_path = Path(local_dir)
                json_files = list(local_path.glob("**/*.json"))
                total_files = len(json_files)
                
                # Log repository stats
                stats = {
                    "Total_Files": total_files,
                    "Local_Dir": str(local_path),
                }
                for line in LogFormatter.stats(stats, "Repository Statistics"):
                    logger.info(line)
                
                if not json_files:
                    raise Exception("No JSON files found in repository")
                
                # Initialize progress tracker
                progress = ProgressTracker(total_files, "PROCESSING FILES")
                
                # Process local files
                model_submissions = {}  # Dict to track latest submission for each (model_id, revision, precision)
                for file_path in json_files:
                    try:
                        with open(file_path, 'r') as f:
                            content = json.load(f)
                            
                        # Get status and determine target status
                        status = content.get("status", "PENDING").upper()
                        target_status = None
                        status_map = {
                            "PENDING": ["PENDING"],
                            "EVALUATING": ["RUNNING"],
                            "FINISHED": ["FINISHED"]
                        }
                        
                        for target, source_statuses in status_map.items():
                            if status in source_statuses:
                                target_status = target
                                break
                                
                        if not target_status:
                            progress.update()
                            continue
                            
                        # Calculate wait time
                        try:
                            submit_time = datetime.fromisoformat(content["submitted_time"].replace("Z", "+00:00"))
                            if submit_time.tzinfo is None:
                                submit_time = submit_time.replace(tzinfo=timezone.utc)
                            current_time = datetime.now(timezone.utc)
                            wait_time = current_time - submit_time
                            
                            model_info = {
                                "name": content["model"],
                                "submitter": content.get("sender", "Unknown"),
                                "revision": content["revision"],
                                "wait_time": f"{wait_time.total_seconds():.1f}s",
                                "submission_time": content["submitted_time"],
                                "status": target_status,
                                "precision": content.get("precision", "Unknown")
                            }
                            
                            # Use (model_id, revision, precision) as key to track latest submission
                            key = (content["model"], content["revision"], content.get("precision", "Unknown"))
                            if key not in model_submissions or submit_time > datetime.fromisoformat(model_submissions[key]["submission_time"].replace("Z", "+00:00")):
                                model_submissions[key] = model_info
                            
                        except (ValueError, TypeError) as e:
                            logger.error(LogFormatter.error(f"Failed to process {file_path.name}", e))
                            
                    except Exception as e:
                        logger.error(LogFormatter.error(f"Failed to load {file_path.name}", e))
                    finally:
                        progress.update()
                
                # Populate models dict with deduplicated submissions
                for model_info in model_submissions.values():
                    models[model_info["status"].lower()].append(model_info)
                
                progress.close()
                
                # Final summary with fancy formatting
                logger.info(LogFormatter.section("CACHE SUMMARY"))
                stats = {
                    "Finished": len(models["finished"]),
                    "Evaluating": len(models["evaluating"]),
                    "Pending": len(models["pending"])
                }
                for line in LogFormatter.stats(stats, "Models by Status"):
                    logger.info(line)
                logger.info("="*50)
                
            except Exception as e:
                logger.error(LogFormatter.error("Error processing files", e))
                raise
            
            # Update cache
            self.cached_models = models
            self.last_cache_update = time.time()
            logger.info(LogFormatter.success("Cache updated successfully"))
            
            return models
            
        except Exception as e:
            logger.error(LogFormatter.error("Cache refresh failed", e))
            raise

    async def initialize(self):
        """Initialize the model service"""
        if self._initialized:
            logger.info(LogFormatter.info("Service already initialized, using cached data"))
            return
        
        try:
            logger.info(LogFormatter.section("MODEL SERVICE INITIALIZATION"))
            
            # Check if cache already exists
            cache_path = cache_config.get_cache_path("datasets")
            if not cache_path.exists() or not any(cache_path.iterdir()):
                logger.info(LogFormatter.info("No existing cache found, initializing datasets cache..."))
                cache_config.flush_cache("datasets")
            else:
                logger.info(LogFormatter.info("Using existing datasets cache"))
            
            # Ensure eval requests directory exists
            self.eval_requests_path.parent.mkdir(parents=True, exist_ok=True)
            logger.info(LogFormatter.info(f"Eval requests directory: {self.eval_requests_path}"))
            
            # List existing files
            if self.eval_requests_path.exists():
                files = list(self.eval_requests_path.glob("**/*.json"))
                stats = {
                    "Total_Files": len(files),
                    "Directory": str(self.eval_requests_path)
                }
                for line in LogFormatter.stats(stats, "Eval Requests"):
                    logger.info(line)
            
            # Load initial cache
            await self._refresh_models_cache()
            
            self._initialized = True
            logger.info(LogFormatter.success("Model service initialization complete"))
            
        except Exception as e:
            logger.error(LogFormatter.error("Initialization failed", e))
            raise

    async def get_models(self) -> Dict[str, List[Dict[str, Any]]]:
        """Get all models with their status"""
        if not self._initialized:
            logger.info(LogFormatter.info("Service not initialized, initializing now..."))
            await self.initialize()
            
        current_time = time.time()
        cache_age = current_time - self.last_cache_update
        
        # Check if cache needs refresh
        if not self.cached_models:
            logger.info(LogFormatter.info("No cached data available, refreshing cache..."))
            return await self._refresh_models_cache()
        elif cache_age > self.cache_ttl:
            logger.info(LogFormatter.info(f"Cache expired ({cache_age:.1f}s old, TTL: {self.cache_ttl}s)"))
            return await self._refresh_models_cache()
        else:
            logger.info(LogFormatter.info(f"Using cached data ({cache_age:.1f}s old)"))
            return self.cached_models

    async def submit_model(
        self, 
        model_data: Dict[str, Any],
        user_id: str
    ) -> Dict[str, Any]:
        logger.info(LogFormatter.section("MODEL SUBMISSION"))
        self._log_repo_operation("write", f"{HF_ORGANIZATION}/requests", f"Submitting model {model_data['model_id']} by {user_id}")
        stats = {
            "Model": model_data["model_id"],
            "User": user_id,
            "Revision": model_data["revision"],
            "Precision": model_data["precision"],
            "Type": model_data["model_type"]
        }
        for line in LogFormatter.tree(stats, "Submission Details"):
            logger.info(line)
        
        # Validate required fields
        required_fields = [
            "model_id", "base_model", "revision", "precision",
            "weight_type", "model_type", "use_chat_template"
        ]
        for field in required_fields:
            if field not in model_data:
                raise ValueError(f"Missing required field: {field}")

        # Get model info and validate it exists on HuggingFace
        try:
            logger.info(LogFormatter.subsection("MODEL VALIDATION"))
            
            # Get the model info to check if it exists
            model_info = self.hf_api.model_info(
                model_data["model_id"],
                revision=model_data["revision"],
                token=self.token
            )
            
            if not model_info:
                raise Exception(f"Model {model_data['model_id']} not found on HuggingFace Hub")
            
            logger.info(LogFormatter.success("Model exists on HuggingFace Hub"))
            
        except Exception as e:
            logger.error(LogFormatter.error("Model validation failed", e))
            raise
        
        # Update model revision with commit sha
        model_data["revision"] = model_info.sha

        # Check if model already exists in the system
        try:
            logger.info(LogFormatter.subsection("CHECKING EXISTING SUBMISSIONS"))
            existing_models = await self.get_models()
            
            # Call the official provider status check
            is_valid, error_message = await self.validator.check_official_provider_status(
                model_data["model_id"],
                existing_models
            )
            if not is_valid:
                raise ValueError(error_message)

            # Check in all statuses (pending, evaluating, finished)
            for status, models in existing_models.items():
                for model in models:
                    if model["name"] == model_data["model_id"] and model["revision"] == model_data["revision"]:
                        error_msg = f"Model {model_data['model_id']} revision {model_data['revision']} is already in the system with status: {status}"
                        logger.error(LogFormatter.error("Submission rejected", error_msg))
                        raise ValueError(error_msg)
            
            logger.info(LogFormatter.success("No existing submission found"))
        except ValueError:
            raise
        except Exception as e:
            logger.error(LogFormatter.error("Failed to check existing submissions", e))
            raise

        # Check that model on hub and valid
        valid, error, model_config = await self.validator.is_model_on_hub(
            model_data["model_id"], 
            model_data["revision"], 
            test_tokenizer=True
        )
        if not valid:
            logger.error(LogFormatter.error("Model on hub validation failed", error))
            raise Exception(error)
        logger.info(LogFormatter.success("Model on hub validation passed"))

        # Validate model card
        valid, error, model_card = await self.validator.check_model_card(
            model_data["model_id"]
        )
        if not valid:
            logger.error(LogFormatter.error("Model card validation failed", error))
            raise Exception(error)
        logger.info(LogFormatter.success("Model card validation passed"))

        # Check size limits
        model_size, error = await self.validator.get_model_size(
            model_info,
            model_data["precision"],
            model_data["base_model"],
            revision=model_data["revision"]
        )
        if model_size is None:
            logger.error(LogFormatter.error("Model size validation failed", error))
            raise Exception(error)
        logger.info(LogFormatter.success(f"Model size validation passed: {model_size:.1f}B"))

        # Size limits based on precision
        if model_data["precision"] in ["float16", "bfloat16"] and model_size > 100:
            error_msg = f"Model too large for {model_data['precision']} (limit: 100B)"
            logger.error(LogFormatter.error("Size limit exceeded", error_msg))
            raise Exception(error_msg)

        # Chat template validation if requested
        if model_data["use_chat_template"]:
            valid, error = await self.validator.check_chat_template(
                model_data["model_id"],
                model_data["revision"]
            )
            if not valid:
                logger.error(LogFormatter.error("Chat template validation failed", error))
                raise Exception(error)
            logger.info(LogFormatter.success("Chat template validation passed"))


        architectures = model_info.config.get("architectures", "")     
        if architectures:
            architectures = ";".join(architectures)

        # Create eval entry
        eval_entry = {
            "model": model_data["model_id"],
            "base_model": model_data["base_model"],
            "revision": model_info.sha,
            "precision": model_data["precision"],
            "params": model_size,
            "architectures": architectures,
            "weight_type": model_data["weight_type"],
            "status": "PENDING",
            "submitted_time": datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ"),
            "model_type": model_data["model_type"],
            "job_id": -1,
            "job_start_time": None,
            "use_chat_template": model_data["use_chat_template"],
            "sender": user_id
        }
        
        logger.info(LogFormatter.subsection("EVALUATION ENTRY"))
        for line in LogFormatter.tree(eval_entry):
            logger.info(line)

        # Upload to HF dataset
        try:
            logger.info(LogFormatter.subsection("UPLOADING TO HUGGINGFACE"))
            logger.info(LogFormatter.info(f"Uploading to {HF_ORGANIZATION}/requests..."))
            
            # Construct the path in the dataset
            org_or_user = model_data["model_id"].split("/")[0] if "/" in model_data["model_id"] else ""
            model_path = model_data["model_id"].split("/")[-1]
            relative_path = f"{org_or_user}/{model_path}_eval_request_False_{model_data['precision']}_{model_data['weight_type']}.json"
            
            # Create a temporary file with the request
            with tempfile.NamedTemporaryFile(mode='w', suffix='.json', delete=False) as temp_file:
                json.dump(eval_entry, temp_file, indent=2)
                temp_file.flush()
                temp_path = temp_file.name
            
            # Upload file directly
            self.hf_api.upload_file(
                path_or_fileobj=temp_path,
                path_in_repo=relative_path,
                repo_id=f"{HF_ORGANIZATION}/requests",
                repo_type="dataset",
                commit_message=f"Add {model_data['model_id']} to eval queue",
                token=self.token
            )
            
            # Clean up temp file
            os.unlink(temp_path)
            
            logger.info(LogFormatter.success("Upload successful"))
            
        except Exception as e:
            logger.error(LogFormatter.error("Upload failed", e))
            raise

        # Add automatic vote
        try:
            logger.info(LogFormatter.subsection("AUTOMATIC VOTE"))
            logger.info(LogFormatter.info(f"Adding upvote for {model_data['model_id']} by {user_id}"))
            await self.vote_service.add_vote(
                model_data["model_id"],
                user_id,
                "up",
                {
                    "precision": model_data["precision"],
                    "revision": model_data["revision"]
                }
            )
            logger.info(LogFormatter.success("Vote recorded successfully"))
        except Exception as e:
            logger.error(LogFormatter.error("Failed to record vote", e))
            # Don't raise here as the main submission was successful

        return {
            "status": "success",
            "message": "The model was submitted successfully, and the vote has been recorded"
        }

    async def get_model_status(self, model_id: str) -> Dict[str, Any]:
        """Get evaluation status of a model"""
        logger.info(LogFormatter.info(f"Checking status for model: {model_id}"))
        eval_path = self.eval_requests_path
        
        for user_folder in eval_path.iterdir():
            if user_folder.is_dir():
                for file in user_folder.glob("*.json"):
                    with open(file, "r") as f:
                        data = json.load(f)
                        if data["model"] == model_id:
                            status = {
                                "status": data["status"],
                                "submitted_time": data["submitted_time"],
                                "job_id": data.get("job_id", -1)
                            }
                            logger.info(LogFormatter.success("Status found"))
                            for line in LogFormatter.tree(status, "Model Status"):
                                logger.info(line)
                            return status
        
        logger.warning(LogFormatter.warning(f"No status found for model: {model_id}"))
        return {"status": "not_found"}

    async def get_organization_submissions(self, organization: str, days: int = 7) -> List[Dict[str, Any]]:
        """Get all submissions from a user in the last n days"""
        try:
            # Get all models
            all_models = await self.get_models()
            current_time = datetime.now(timezone.utc)
            cutoff_time = current_time - timedelta(days=days)
            
            # Filter models by submitter and submission time
            user_submissions = []
            for status, models in all_models.items():
                for model in models:
                    # Check if model was submitted by the user
                    if model["submitter"] == organization:
                        # Parse submission time
                        submit_time = datetime.fromisoformat(
                            model["submission_time"].replace("Z", "+00:00")
                        )
                        # Check if within time window
                        if submit_time > cutoff_time:
                            user_submissions.append({
                                "name": model["name"],
                                "status": status,
                                "submission_time": model["submission_time"],
                                "precision": model["precision"]
                            })
            
            return sorted(
                user_submissions,
                key=lambda x: x["submission_time"],
                reverse=True
            )
            
        except Exception as e:
            logger.error(LogFormatter.error(f"Failed to get submissions for {organization}", e))
            raise