import uuid
import time
from typing import Dict, Optional, Any
from dataclasses import dataclass, field
from enum import Enum
import threading
from pathlib import Path

class JobStatus(str, Enum):
    PENDING = "pending"
    PROCESSING = "processing"
    COMPLETED = "completed"
    FAILED = "failed"

@dataclass
class Job:
    job_id: str
    status: JobStatus
    progress: float = 0.0
    message: str = ""
    result: Optional[Any] = None
    error: Optional[str] = None
    created_at: float = field(default_factory=time.time)
    updated_at: float = field(default_factory=time.time)
    total_steps: int = 100
    current_step: int = 0

class ProgressTracker:
    _instance = None
    _init_lock = threading.Lock()
    
    def __new__(cls):
        if cls._instance is None:
            with cls._init_lock:
                if cls._instance is None:
                    cls._instance = super().__new__(cls)
                    cls._instance._jobs: Dict[str, Job] = {}
                    cls._instance._lock = threading.RLock()
                    cls._instance._cleanup_interval = 300
                    cls._instance._file_cleanup_interval = 600
        return cls._instance
    
    def create_job(self, message: str = "Starting...") -> str:
        job_id = str(uuid.uuid4())
        with self._lock:
            self._jobs[job_id] = Job(
                job_id=job_id,
                status=JobStatus.PENDING,
                message=message
            )
            self._cleanup_old_jobs_locked()
        return job_id
    
    def update_progress(self, job_id: str, progress: float, message: str = "", 
                       current_step: int = 0, total_steps: int = 100):
        with self._lock:
            if job_id in self._jobs:
                job = self._jobs[job_id]
                job.progress = min(progress, 100.0)
                job.current_step = current_step
                job.total_steps = total_steps
                if message:
                    job.message = message
                job.status = JobStatus.PROCESSING
                job.updated_at = time.time()
    
    def complete_job(self, job_id: str, result: Any = None, message: str = "Completed"):
        with self._lock:
            if job_id in self._jobs:
                job = self._jobs[job_id]
                job.status = JobStatus.COMPLETED
                job.progress = 100.0
                job.message = message
                job.result = result
                job.updated_at = time.time()
    
    def fail_job(self, job_id: str, error: str):
        with self._lock:
            if job_id in self._jobs:
                job = self._jobs[job_id]
                job.status = JobStatus.FAILED
                job.error = error
                job.message = f"Failed: {error}"
                job.updated_at = time.time()
    
    def get_job(self, job_id: str) -> Optional[Job]:
        with self._lock:
            job = self._jobs.get(job_id)
            if job:
                return Job(
                    job_id=job.job_id,
                    status=job.status,
                    progress=job.progress,
                    message=job.message,
                    result=job.result,
                    error=job.error,
                    created_at=job.created_at,
                    updated_at=job.updated_at,
                    total_steps=job.total_steps,
                    current_step=job.current_step
                )
            return None
    
    def get_progress(self, job_id: str) -> Optional[dict]:
        with self._lock:
            job = self._jobs.get(job_id)
            if job is None:
                return None
            return {
                "job_id": job.job_id,
                "status": job.status.value,
                "progress": round(job.progress, 1),
                "message": job.message,
                "current_step": job.current_step,
                "total_steps": job.total_steps,
                "has_result": job.result is not None,
                "error": job.error
            }
    
    def remove_job_and_cleanup(self, job_id: str) -> Optional[str]:
        """Remove a job and return the result file path for deletion."""
        with self._lock:
            job = self._jobs.pop(job_id, None)
            if job and job.result:
                return str(job.result)
            return None
    
    def _cleanup_old_jobs_locked(self):
        """Must be called with self._lock held."""
        current_time = time.time()
        expired_jobs = [
            job_id for job_id, job in self._jobs.items()
            if current_time - job.updated_at > self._cleanup_interval
            and job.status in (JobStatus.COMPLETED, JobStatus.FAILED)
        ]
        files_to_delete = []
        for job_id in expired_jobs:
            job = self._jobs.pop(job_id, None)
            if job and job.result:
                files_to_delete.append(str(job.result))
        
        for file_path in files_to_delete:
            try:
                path = Path(file_path)
                if path.exists():
                    path.unlink()
            except Exception:
                pass

def get_tracker() -> ProgressTracker:
    return ProgressTracker()