Fix Alacritty configuration script and docs

Alacritty looks for its configuration files in a small range of folders on OSX
and other unix systems

When getting started with this project I noticed that on OSX the user_config_dir
defaults to "[/Users/username/Library/Application Support](https://github.com/ActiveState/appdirs#some-example-output)"
This location is not among the locations Alacritty looks for according to [their own docs](https://github.com/alacritty/alacritty#configuration),
so installing a theme was bit of a pain.

I moved some stuff around to make the install script a little bit smarter, I
then also created a requirements.txt file to go along with the python file to
make sure users know what dependencies work with the script.

Installation of a theme also performs destructive/constructive actions on the
main configuration file for Alacritty so I also included a little prompt for the
user to double check if they really really want to write to the config file.

Lastly I updated the installation instructions to help alacritty users get
started

Unrelated (biased) side-point:
Most Unix terminal config lives in ~/.config/your_app_name these days. `src` is
bit of a weird name for a pretty specific theme engine on someone's computer.
I'm not going to make the change here, but I would deffo reccomend updating
documentation and scripts to install Gogh to the config DIR instead.

README.md

@@ -57,11 +57,18 @@ bash -c "$(curl -sLo- https://git.io/vQgMr)"
 mkdir -p "$HOME/src"
 cd "$HOME/src"
 git clone https://github.com/Gogh-Co/Gogh.git gogh
-cd gogh/themes
+cd gogh
 
-# necessary on ubuntu
+# necessary in the Gnome terminal on ubuntu
 export TERMINAL=gnome-terminal
 
+# necessary in the Alacritty terminal
+pip install -r requirements.txt
+export TERMINAL=alacritty
+
+# Enter themes dir
+cd themes
+
 # install themes
 ./atom.sh
 ./dracula.sh
@@ -69,6 +76,7 @@ export TERMINAL=gnome-terminal
 
 ## 💻 Terminals
 
+- Alacritty - [Web](https://github.com/alacritty/alacritty)
 - Cygwin - [Web](https://www.cygwin.com/)
 - Foot - [Web](https://codeberg.org/dnkl/foot)
 - Gnome - [Web](https://help.gnome.org/users/gnome-terminal/stable/)

apply-alacritty.py

@@ -1,23 +1,77 @@
 import io
 import json
 import sys
-from appdirs import user_config_dir
+import os
 from ruamel.yaml import YAML  # use ruamel.yaml to preserve comments in config
 
 
+def get_conf_path():
+    # Determine system
+    # When we are in some Java world do extra checks
+    if sys.platform.startswith('java'):
+        import platform
+        os_name = platform.java_ver()[3][0]
+        if os_name.startswith('Windows'):  # "Windows XP", "Windows 7", etc.
+            system = 'win32'
+        else:  # anything that isn't windows ("darwin", "Linux", "SunOS", "FreeBSD", "Arch", etc.)
+            system = 'linux2'
+    else:
+        system = sys.platform
+
+    if system == 'win32':
+        # In windows alacritty config can only exist in one place
+        alacritty_path = os.path.expandvars(r'%APPDATA%\alacritty\alacritty.yml')
+        if os.path.exists(alacritty_path):
+            return alacritty_path
+    else:
+        # If it is not win32 it can exists in only a few other places
+        xdg_config_home = os.getenv('XDG_CONFIG_HOME')
+        if xdg_config_home is not None and os.path.exists(xdg_config_home + '/alacritty/alacritty.yml'):
+            return xdg_config_home + "/alacritty/alacritty.yml"
+        if xdg_config_home is not None and os.path.exists(xdg_config_home + "/alacritty.yml"):
+            return xdg_config_home + "/alacritty.yml"
+
+        home = os.getenv('HOME')
+        if home is not None and os.path.exists(home + '/.config/alacritty/alacritty.yml'):
+            return home + "/.config/alacritty/alacritty.yml"
+        if home is not None and os.path.exists(home + '/.config/alacritty.yml'):
+            return home + "/.config/alacritty.yml"
+        if home is not None and os.path.exists(home + 'alacritty.yml'):
+            return home + "/alacritty.yml"
+
+    print("Could not find alacritty config file\nPlease make sure you have a file in one of the paths specified on\nhttps://github.com/alacritty/alacritty#configuration")
+    sys.exit(1)
+# end
+
+
+conf_path = get_conf_path()
 yaml = YAML()
-conf = user_config_dir('alacritty') + "/alacritty.yml"
-# Read alacritty config
-with open(conf, 'r') as stream:
+
+# Read & parse alacritty config
+with open(conf_path, 'r') as stream:
     data_loaded = yaml.load(stream)
 
+# parse new colors
 js = json.loads(sys.argv[1])
 
+# Update yaml file
+try:
     # Use update to not remove existing comments
     data_loaded['colors']['primary'].update(js['colors']['primary'])
     data_loaded['colors']['normal'].update(js['colors']['normal'])
     data_loaded['colors']['bright'].update(js['colors']['bright'])
+except KeyError:
+    print("Could not find existing 'colors' settings in your alacritty.yml file\nplease make sure to uncomment\n'colors', as well as 'primary', 'normal' and 'bright'")
+    print("Check the example config at\nhttps://github.com/alacritty/alacritty/blob/master/alacritty.yml for more information")
+    sys.exit(1)
+
+# make sure the user is okay with having their config changed
+answer = input("This script will update your alacritty config at: \n" +
+               conf_path + "\nIt is reccomended to make a copy of this file before proceeding.\nAre you sure you want to continue? (Y/N)\n")
+if not answer.lower() in ['y', 'yes']:
+    print("Aborted")
+    sys.exit(1)
 
 # Write alacritty config
-with io.open(conf, 'w', encoding='utf8') as outfile:
+with io.open(conf_path, 'w', encoding='utf8') as outfile:
     yaml.dump(data_loaded, outfile)

requirements.txt

@@ -0,0 +1,2 @@
+ruamel.yaml==0.17.21
+