Files
littleprynter/src/print_queue.py
2026-05-22 11:01:06 +02:00

127 lines
4.7 KiB
Python

# This class has the method by which we manage the Tasks
# It's a printing queue, so we need to add, remove and get information on where
# the queue is
from collections import deque
# Because actually printing and adding new print job requests happen at
# diffrent times, the print queue is managed by it's own thread.
import threading
from datetime import datetime
from task import TaskType, CutTask
class PrintQueue:
"""
A Double-ended Queue to manage the printing Tasks
"""
def __init__(self, app):
self.app = app
self._queue = deque()
self._lock = threading.Lock()
self._completed_tasks = {} # Store completed task info
self._task_counter = 0
self.app.logger.debug("Created a new PrintQueue")
def __len__(self) -> int:
return len(self._queue)
def enqueue(self, task):
"""Add task to right of the queue and return position"""
with self._lock:
try:
self.app.logger.info("Add task %s to queue ", task.task_id)
self._queue.append(task)
position = self._queue.index(task)
# We return the current position of the task if it was added
self.app.logger.debug("Added a new task %s to the queue at position %s", task.task_id, position)
return position
except Exception as e:
self.app.logger.error("Could not add a task to the queue : %s ", e)
raise e
def dequeue(self):
"""Remove and return next task ( from the left of the queue ) (thread-safe)"""
with self._lock:
return self._queue.popleft() if len(self._queue) > 0 else None
def get_position(self, task):
"""Get current position of task in queue (1-indexed)"""
with self._lock:
if task.task_id in self._completed_tasks:
return None # Task already completed
try:
# Try to get the position of a Task
return self._queue.index(task)
except ValueError as e:
raise e
# end try
def is_empty(self):
"""Check if queue is empty"""
with self._lock:
self.app.logger.debug("Checking if queue is empty")
return len(self._queue) == 0
def get_queue_state(self):
"""Return current queue state"""
with self._lock:
self.app.logger.debug("Return current queue state")
return [{"task_id": t.task_id, "status": t.status} for t in self._queue]
def get_status(self, task_id):
"""Get full status info for a task"""
with self._lock:
if task_id in self._completed_tasks:
return self._completed_tasks[task_id]
# Check in queue if it exists
for index, task in enumerate(self._queue):
if task.task_id == task_id:
# Depending on it's type, we return more info
if task.task_type == TaskType.IMAGE:
return {
"task_id": task_id,
"status": task.status,
"type" : task.task_type,
"position": index,
"in_queue": True,
"content" : task.content,
"signature": task.signature
}
if task.task_type == TaskType.TEXT:
return {
"task_id": task_id,
"status": task.status,
"type" : task.task_type,
"position": index,
"in_queue": True,
"image_path" : str(task.image_path),
"signature" : task.signature,
"process" : str(task.process)
}
if task.task_type == TaskType.CUT:
return {
"task_id": task_id,
"status": task.status,
"type" : task.task_type,
"position": index,
"in_queue": True
}
return None
def mark_completed(self, task_id, task_status):
"""Mark task as completed and remove from queue"""
with self._lock:
self._completed_tasks[task_id] = {
"task_id": task_id,
"status": task_status,
"position": None,
"in_queue": False,
"completed_at": datetime.now().isoformat()
}