From 35725aa381d187c9cbbd4cdd8c684f98927e8bec Mon Sep 17 00:00:00 2001
From: Karl Hudgell <karl.hudgell@bjss.com>
Date: Fri, 20 Sep 2024 11:13:04 +0100
Subject: [PATCH] check current playing disc

---
 lib/mqtt.py | 66 +++++++++++++++++++++++++++++++++++++++++------------
 main.py     | 22 +++++++++++++-----
 2 files changed, 67 insertions(+), 21 deletions(-)

diff --git a/lib/mqtt.py b/lib/mqtt.py
index 66e9a38..9458cf3 100644
--- a/lib/mqtt.py
+++ b/lib/mqtt.py
@@ -1,17 +1,18 @@
 import paho.mqtt.client as mqtt
+import paho.mqtt.subscribe as subscribe
 import json
 
-def create_client(broker:str, port:int, username:str, password:str)-> mqtt:
-    """_summary_
+def create_client(broker: str, port: int, username: str, password: str) -> mqtt.Client:
+    """Create an MQTT client and connect it to the broker
 
     Args:
-        broker (str): _description_
-        port (int): _description_
-        username (str): _description_
-        password (str): _description_
+        broker (str): MQTT broker address
+        port (int): MQTT broker port
+        username (str): Username for MQTT broker
+        password (str): Password for MQTT broker
 
     Returns:
-        mqtt: _description_
+        mqtt.Client: Connected MQTT client instance
     """    
     # Create a new MQTT client instance
     client = mqtt.Client()
@@ -24,11 +25,11 @@ def create_client(broker:str, port:int, username:str, password:str)-> mqtt:
     
     return client
 
-def create_config(client:mqtt)->None:
+def create_config(client: mqtt.Client) -> None:
     """Create Home Assistant discovery topics
 
     Args:
-        client (mqtt): MQTT Client
+        client (mqtt.Client): MQTT Client
     """    
     # Device-specific information for multiple sensors
     node_id = "floppy_player"  # Unique device ID
@@ -70,24 +71,59 @@ def create_config(client:mqtt)->None:
     client.publish(discovery_topic_disc, json.dumps(disc_config), retain=True)
     client.publish(discovery_topic_status, json.dumps(status_config), retain=True)
 
-def update_disc(client:mqtt, disc_message:dict)->None:
+
+def check_current_disc(client: mqtt.Client) -> str:
+    """Check the current loaded disc by subscribing to the retained message on the state topic.
+
+    Args:
+        client (mqtt.Client): MQTT Client
+
+    Returns:
+        str: Current object at current_disc/state
+    """    
+    def on_message(client, userdata, message):
+        """Callback function to handle received MQTT messages."""
+        userdata['message'] = message.payload.decode()
+    
+    # Create a dictionary to store the message
+    userdata = {'message': None}
+
+    # Set the user data and the on_message callback
+    client.user_data_set(userdata)
+    client.on_message = on_message
+
+    # Subscribe to the topic
+    client.subscribe("homeassistant/sensor/floppy_player/current_disc/state")
+
+    # Run the loop manually until we receive a message
+    timeout = 5  # Timeout after 5 seconds
+    while userdata['message'] is None and timeout > 0:
+        client.loop(timeout=0.1)  # Process network events for a short time
+        timeout -= 0.1
+
+    # Check if we received the message
+    if userdata['message'] is None:
+        raise TimeoutError("No retained message was found.")
+
+    return userdata['message']
+
+
+def update_disc(client: mqtt.Client, disc_message: dict) -> None:
     """Update current disc.
 
     Args:
-        client (mqtt): MQTT Client
+        client (mqtt.Client): MQTT Client
         disc_message (dict): Current disc information
     """
     client.publish("homeassistant/sensor/floppy_player/current_disc/state", json.dumps(disc_message), retain=True)
     print(f"Published current disc: {disc_message}")
 
-
-def control_player(client:mqtt, state:str)->None:
+def control_player(client: mqtt.Client, state: str) -> None:
     """Control the player
 
     Args:
-        client (mqtt): MQTT Client
+        client (mqtt.Client): MQTT Client
         state (str): Player State
     """    
     client.publish("homeassistant/sensor/floppy_player/status/state", state, retain=True)
     print(f"Published status: {state}")
-    
\ No newline at end of file
diff --git a/main.py b/main.py
index d60015d..c0c01f4 100644
--- a/main.py
+++ b/main.py
@@ -2,7 +2,7 @@ import os
 import sys
 import json
 from dotenv import load_dotenv
-from lib.mqtt import create_client, update_disc, control_player, create_config
+from lib.mqtt import create_client, update_disc, control_player, create_config, check_current_disc
 
 # Load the .env file
 load_dotenv()
@@ -27,16 +27,26 @@ if len(sys.argv) > 1:
 
     try:
         # Convert the JSON string into a dictionary
-        disc_data = json.loads(json_str)
-        # Pass the parsed data to the update_disc function
-        update_disc(client, disc_data)
+        disc_data = json.loads(json_str.replace("'",'"'))
+        # Check if disc is the same as last inserted
+        if (disc_data == json.loads(check_current_disc(client))):
+            # If disc is the same, PLAY
+            control_player(client, "PLAY")
+        else:
+            # Pass the parsed data to the update_disc function
+            control_player(client, "PLAY")
+            update_disc(client, disc_data)
     except json.JSONDecodeError as e:
         try:
             if json_str == "EJECT":
-                control_player(client, "EJECT")
-                update_disc(client, {"type": "album", "id": "EJECT"})
+                # PAUSE the current playing item
+                control_player(client, "PAUSE")
             elif json_str == "PLAY":
+                # PLAY the current playing item
                 control_player(client, "PLAY")
+            elif json_str == "PAUSE":
+                # PAUSE the current playing item
+                control_player(client, "PAUSE")                
             else:
                 print(f"Can't process {json_str}")
         except Exception: