From fe951ab1d883e8a0e73733e5f847a347cce87d89 Mon Sep 17 00:00:00 2001
From: David Rollinson <g7gpr@outlook.com>
Date: Sun, 10 Jan 2021 11:28:45 +0800
Subject: [PATCH] Add capability to display last received telemetry after
 restart

---
 chasemapper/config.py   | 17 ++++++++++--
 chasemapper/logread.py  | 61 +++++++++++++++++++++++++++++++++++++++++
 horusmapper.cfg.example |  6 ++--
 horusmapper.py          | 13 +++++++++
 4 files changed, 93 insertions(+), 4 deletions(-)
 create mode 100644 chasemapper/logread.py

diff --git a/chasemapper/config.py b/chasemapper/config.py
index b335960..8c7bfa3 100644
--- a/chasemapper/config.py
+++ b/chasemapper/config.py
@@ -42,8 +42,8 @@ default_config = {
     'range_ring_color': 'red',
     'range_ring_custom_color': '#FF0000',
 
-	# Chase Car Speedometer
-	'chase_car_speed': True,
+    # Chase Car Speedometer
+    'chase_car_speed': True,
 
     # Bearing processing
     'max_bearings': 300,
@@ -54,6 +54,9 @@ default_config = {
     'bearing_color': 'black',
     'bearing_custom_color': '#FF0000',
 
+    # History 
+    'reload_last_position': True
+
     }
 
 
@@ -179,11 +182,21 @@ def parse_config_file(filename):
 		logging.critical("Default profile selection does not exist.")
 		return None
 
+        # History
+	logging.info("Checking to see if reload_last_position is set")
+	chase_config['reload_last_position'] = config.getboolean('history', 'reload_last_position', fallback=False)
+	if (chase_config['reload_last_position']):
+           logging.info("Scanning logs to reload last position")
+	else:
+           logging.info("Not scanning logs to reload last position")
+	   
+
 	return chase_config
 
 
 
 
+
 def read_config(filename, default_cfg="horusmapper.cfg.example"):
 	""" Read in a Horus Mapper configuration file,and return as a dict. """
 
diff --git a/chasemapper/logread.py b/chasemapper/logread.py
new file mode 100644
index 0000000..0439d18
--- /dev/null
+++ b/chasemapper/logread.py
@@ -0,0 +1,61 @@
+#!/usr/bin/env python
+#
+#   Project Horus - Log read operations
+#
+#   Copyright (C) 2019  Mark Jessop <vk5qi@rfhead.net>
+#   Released under GNU GPL v3 or later
+#
+import datetime
+import json
+import logging
+import os
+import pytz
+import time
+from threading import Thread, Lock
+try:
+    # Python 2
+    from Queue import Queue
+except ImportError:
+    # Python 3
+    from queue import Queue
+from datetime import datetime
+
+
+
+def read_file(filename):
+    """ Read log file, and output an array of dicts. """
+    _output = []
+
+    _f = open(filename, 'r')
+    for _line in _f:
+        try:
+            _data = json.loads(_line)
+            _output.append(_data)
+        except Exception as e:
+            logging.debug("Error reading line: %s" % str(e))
+    if len(_output) != 0 :
+        logging.info("Read %d log entries from %s" % (len(_output), filename))
+
+    return _output
+
+
+
+def read_last_balloon_telemetry(log_dir):
+        """ Read last balloon telemetry. Need to work back from last file to find balloon telemetry and read the last entry - don't return until whole file scanned
+        """
+        _lasttelemetry = []
+        dirs = sorted(os.listdir("./log_files"),reverse = True) # Generate a reverse sorted list - will have to look through to find last log_file with telemetry
+        for file in dirs:
+           if file.endswith(".log"):
+                telemetry_found = False
+                try:
+                  log = read_file("./log_files/" + file)
+                except Exception as e:
+                  logging.debug("Error reading file - maybe in use")
+                for _entry in log:
+                    if _entry['log_type'] == "BALLOON TELEMETRY":
+                      telemetry_found = True
+                if telemetry_found == True:
+                    logging.info("Last balloon telemetry at %s, %s, %.5f, %.5f" % (_entry['callsign'], _entry['time'], _entry['lat'],_entry['lon']))
+                    _entry['time_dt'] = datetime.fromisoformat(_entry.pop('time')) 
+                    return _entry
diff --git a/horusmapper.cfg.example b/horusmapper.cfg.example
index 18611ce..2a5432a 100644
--- a/horusmapper.cfg.example
+++ b/horusmapper.cfg.example
@@ -242,7 +242,9 @@ unitselection = metric
 # This is the threshold for switching from miles to feet, set in metres.
 switch_miles_feet = 400
 
-
-
+[history]
+
+# Enable load of last position from log files (True/False)
+reload_last_postion = True
 
 
diff --git a/horusmapper.py b/horusmapper.py
index b02545c..55089e0 100644
--- a/horusmapper.py
+++ b/horusmapper.py
@@ -28,6 +28,7 @@ from chasemapper.listeners import OziListener, UDPListener, fix_datetime
 from chasemapper.predictor import predictor_spawn_download, model_download_running
 from chasemapper.habitat import HabitatChaseUploader, initListenerCallsign, uploadListenerPosition
 from chasemapper.logger import ChaseLogger
+from chasemapper.logread import read_last_balloon_telemetry
 from chasemapper.bearings import Bearings
 from chasemapper.tawhiri import get_tawhiri_prediction
 
@@ -998,6 +999,18 @@ if __name__ == "__main__":
         habitat_uploader = HabitatChaseUploader(update_rate = chasemapper_config['habitat_update_rate'],
                 callsign=chasemapper_config['habitat_call'])
 
+    # Read in last known position, if enabled
+
+    if chasemapper_config['reload_last_position']:
+         logging.info("Read in last position requested")
+         try:
+          handle_new_payload_position(read_last_balloon_telemetry("./log_dir"));
+         except Exception as e:
+          logging.info("Unable to read in last position")         
+    else:
+         logging.info("Read in last position not requested")
+         
+
     # Start up the data age monitor thread.
     _data_age_monitor = Thread(target=check_data_age)
     _data_age_monitor.start()