EDMarketConnector: Change 'no other .exe runnig?' checks

* This is now done even before the stdout/err redirect.
* The function is now called no_other_instance_running() to make the
  conditional use of it read more naturally.
* For now this *append* logs to the plain log file.  **BUT** any
  subsequent write by the already-running process will be over the top
  of this, so a future commit will use a popup instead.

# Conflicts:
#	EDMarketConnector.py

EDMarketConnector.py

@@ -18,9 +18,96 @@ from typing import TYPE_CHECKING, Any, Mapping, Optional, Tuple
 
 from constants import applongname, appname, protocolhandler_redirect
 
-# config will now cause an appname logger to be set up, so we need the
+# TODO: Test: Make *sure* this redirect is working, else py2exe is going to cause an exit popup
-# console redirect before this
+# TODO: Move enforce_single_instance() call here ?  But then how do we notify
-if __name__ == '__main__':
+#       the user if they already have a process ?
+#       We could propagate what that found all the way up and then do the stderr/out redirect
+#       in a non-truncate manner.  Need to double-check the existing process won't then overwrite
+#       due to its seek position.
+def no_other_instance_running() -> bool:  # noqa: CCR001
+    """
+    Ensure only one copy of the app is running under this user account.
+
+    OSX does this automatically.
+
+    :returns: True if we are the single instance, else False.
+    """
+    # TODO: Linux implementation
+    if platform == 'win32':
+        import ctypes
+        from ctypes.wintypes import BOOL, HWND, INT, LPARAM, LPCWSTR, LPWSTR
+
+        EnumWindows = ctypes.windll.user32.EnumWindows  # noqa: N806
+        GetClassName = ctypes.windll.user32.GetClassNameW  # noqa: N806
+        GetClassName.argtypes = [HWND, LPWSTR, ctypes.c_int]
+        GetWindowText = ctypes.windll.user32.GetWindowTextW  # noqa: N806
+        GetWindowText.argtypes = [HWND, LPWSTR, ctypes.c_int]
+        GetWindowTextLength = ctypes.windll.user32.GetWindowTextLengthW  # noqa: N806
+        GetProcessHandleFromHwnd = ctypes.windll.oleacc.GetProcessHandleFromHwnd  # noqa: N806
+
+        SW_RESTORE = 9  # noqa: N806
+        SetForegroundWindow = ctypes.windll.user32.SetForegroundWindow  # noqa: N806
+        ShowWindow = ctypes.windll.user32.ShowWindow  # noqa: N806
+        ShowWindowAsync = ctypes.windll.user32.ShowWindowAsync  # noqa: N806
+
+        COINIT_MULTITHREADED = 0  # noqa: N806,F841
+        COINIT_APARTMENTTHREADED = 0x2  # noqa: N806
+        COINIT_DISABLE_OLE1DDE = 0x4  # noqa: N806
+        CoInitializeEx = ctypes.windll.ole32.CoInitializeEx  # noqa: N806
+
+        ShellExecute = ctypes.windll.shell32.ShellExecuteW  # noqa: N806
+        ShellExecute.argtypes = [HWND, LPCWSTR, LPCWSTR, LPCWSTR, LPCWSTR, INT]
+
+        def window_title(h):
+            if h:
+                text_length = GetWindowTextLength(h) + 1
+                buf = ctypes.create_unicode_buffer(text_length)
+                if GetWindowText(h, buf, text_length):
+                    return buf.value
+
+            return None
+
+        @ctypes.WINFUNCTYPE(BOOL, HWND, LPARAM)
+        def enumwindowsproc(window_handle, l_param):
+            # class name limited to 256 - https://msdn.microsoft.com/en-us/library/windows/desktop/ms633576
+            cls = ctypes.create_unicode_buffer(257)
+            if GetClassName(window_handle, cls, 257) \
+                    and cls.value == 'TkTopLevel' \
+                    and window_title(window_handle) == applongname \
+                    and GetProcessHandleFromHwnd(window_handle):
+                # If GetProcessHandleFromHwnd succeeds then the app is already running as this user
+                if len(sys.argv) > 1 and sys.argv[1].startswith(protocolhandler.redirect):
+                    CoInitializeEx(0, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE)
+                    # Wait for it to be responsive to avoid ShellExecute recursing
+                    ShowWindow(window_handle, SW_RESTORE)
+                    ShellExecute(0, None, sys.argv[1], None, None, SW_RESTORE)
+
+                else:
+                    ShowWindowAsync(window_handle, SW_RESTORE)
+                    SetForegroundWindow(window_handle)
+
+                return False
+
+            return True
+
+        return EnumWindows(enumwindowsproc, 0)
+
+if __name__ == "__main__":
+    if not no_other_instance_running():
+        # There's a copy already running.  We want to inform the user by
+        # **appending** to the log file, not truncating it.
+        if getattr(sys, 'frozen', False):
+            # By default py2exe tries to write log to dirname(sys.executable) which fails when installed
+            import tempfile
+
+            # unbuffered not allowed for text in python3, so use `1 for line buffering
+            sys.stdout = sys.stderr = open(join(tempfile.gettempdir(), f'{appname}.log'), mode='a', buffering=1)
+
+        # Logging isn't set up yet
+        print("An EDMarketConnector.exe process was already running, exiting.")
+
+        sys.exit(0)
+
     # Keep this as the very first code run to be as sure as possible of no
     # output until after this redirect is done, if needed.
     if getattr(sys, 'frozen', False):
@@ -1306,77 +1393,6 @@ class AppWindow(object):
             self.blank_menubar.grid(row=0, columnspan=2, sticky=tk.NSEW)
 
 
-def enforce_single_instance() -> None:  # noqa: CCR001
-    """
-    Ensure only one copy of the app is running under this user account.
-
-    OSX does this automatically.
-    """
-    # TODO: Linux implementation
-    if platform == 'win32':
-        import ctypes
-        from ctypes.wintypes import BOOL, HWND, INT, LPARAM, LPCWSTR, LPWSTR
-
-        EnumWindows = ctypes.windll.user32.EnumWindows  # noqa: N806
-        GetClassName = ctypes.windll.user32.GetClassNameW  # noqa: N806
-        GetClassName.argtypes = [HWND, LPWSTR, ctypes.c_int]
-        GetWindowText = ctypes.windll.user32.GetWindowTextW  # noqa: N806
-        GetWindowText.argtypes = [HWND, LPWSTR, ctypes.c_int]
-        GetWindowTextLength = ctypes.windll.user32.GetWindowTextLengthW  # noqa: N806
-        GetProcessHandleFromHwnd = ctypes.windll.oleacc.GetProcessHandleFromHwnd  # noqa: N806
-
-        SW_RESTORE = 9  # noqa: N806
-        SetForegroundWindow = ctypes.windll.user32.SetForegroundWindow  # noqa: N806
-        ShowWindow = ctypes.windll.user32.ShowWindow  # noqa: N806
-        ShowWindowAsync = ctypes.windll.user32.ShowWindowAsync  # noqa: N806
-
-        COINIT_MULTITHREADED = 0  # noqa: N806,F841
-        COINIT_APARTMENTTHREADED = 0x2  # noqa: N806
-        COINIT_DISABLE_OLE1DDE = 0x4  # noqa: N806
-        CoInitializeEx = ctypes.windll.ole32.CoInitializeEx  # noqa: N806
-
-        ShellExecute = ctypes.windll.shell32.ShellExecuteW  # noqa: N806
-        ShellExecute.argtypes = [HWND, LPCWSTR, LPCWSTR, LPCWSTR, LPCWSTR, INT]
-
-        def window_title(h):
-            if h:
-                text_length = GetWindowTextLength(h) + 1
-                buf = ctypes.create_unicode_buffer(text_length)
-                if GetWindowText(h, buf, text_length):
-                    return buf.value
-
-            return None
-
-        @ctypes.WINFUNCTYPE(BOOL, HWND, LPARAM)
-        def enumwindowsproc(window_handle, l_param):
-            # class name limited to 256 - https://msdn.microsoft.com/en-us/library/windows/desktop/ms633576
-            cls = ctypes.create_unicode_buffer(257)
-            if GetClassName(window_handle, cls, 257) \
-                    and cls.value == 'TkTopLevel' \
-                    and window_title(window_handle) == applongname \
-                    and GetProcessHandleFromHwnd(window_handle):
-                # If GetProcessHandleFromHwnd succeeds then the app is already running as this user
-                if len(sys.argv) > 1 and sys.argv[1].startswith(protocolhandler.redirect):
-                    # logger.debug('Browser invoked us directly with auth response. '
-                    #              'Forwarding the response to the other app instance.')
-                    CoInitializeEx(0, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE)
-                    # Wait for it to be responsive to avoid ShellExecute recursing
-                    ShowWindow(window_handle, SW_RESTORE)
-                    ShellExecute(0, None, sys.argv[1], None, None, SW_RESTORE)
-
-                else:
-                    ShowWindowAsync(window_handle, SW_RESTORE)
-                    SetForegroundWindow(window_handle)
-
-                # logger.info(f'A running {applongname} process was found, exiting.')
-                return False
-
-            return True
-
-        if not EnumWindows(enumwindowsproc, 0):
-            sys.exit(0)
-
-
 def test_logging() -> None:
     """Simple test of top level logging."""
     logger.debug('Test from EDMarketConnector.py top-level test_logging()')
@@ -1394,7 +1410,29 @@ Locale LC_TIME: {locale.getlocale(locale.LC_TIME)}'''
 
 
 # Run the app
-if __name__ == "__main__":  # noqa C901
+if __name__ == "__main__":
+    # Command-line arguments
+    parser = argparse.ArgumentParser(
+        prog=appname,
+        description="Utilises Elite Dangerous Journal files and the Frontier "
+                    "Companion API (CAPI) service to gather data about a "
+                    "player's state and actions to upload to third-party sites "
+                    "such as EDSM, Inara.cz and EDDB."
+    )
+
+    parser.add_argument('--trace',
+                        help='Set the Debug logging loglevel to TRACE',
+                        action='store_true',
+                        )
+
+    args = parser.parse_args()
+
+    if args.trace:
+        logger.setLevel(logging.TRACE)
+        edmclogger.set_channels_loglevel(logging.TRACE)
+    else:
+        edmclogger.set_channels_loglevel(logging.DEBUG)
+
     logger.info(f'Startup v{appversion} : Running on Python v{sys.version}')
     logger.debug(f'''Platform: {sys.platform} {sys.platform == "win32" and sys.getwindowsversion()}
 argv[0]: {sys.argv[0]}