improved readability

install.sh

@@ -1,39 +1,49 @@
 #!/bin/bash
 
+## CONSTANTS
 
-function install() {
+readonly CURDIR=$PWD
+readonly REQUIRED_PKGS=(file git bc)
+readonly MAIN_TAR_GZ_URL="https://git.artcode.re/miaou/miaou-bash/archive/main.tar.gz"
+
+## FUNCTIONS
+
+function push_directory {
+    pushd "$1" || echo "unable to push directory <$1>" && exit 1
+}
+
+function pop_directory {
+    popd || echo "unable to pop from previous directory" && exit 1
+}
+
+function root_required {
     [ "$(id -u)" -ne 0 ] && echo 'root privilege required' && exit 1
-
-    if [[ ! $CURDIR == '/opt/miaou-bash' ]]; then
-        # download and fullfill /opt/miaou-bash, then run it from folder
-
-        if [[ -L /opt/miaou-bash ]]; then
-            cd /opt/miaou-bash && ./install.sh
-            exit 0
-        else
-            rm -rf /opt/miaou-bash
-            TEMP=$(mktemp -d)
-            cd "$TEMP" || return
-            echo "$TEMP"
-            wget https://git.artcode.re/miaou/miaou-bash/archive/main.tar.gz
-            tar -xzf main.tar.gz
-            mv miaou-bash /opt/
-            cd /opt/miaou-bash || return
-            ./install.sh "$PARAM1"
-            rm -rf "$TEMP"
-            exit 0
-        fi
-
-    else
-        apt-get update
-        apt-get install -y "${REQUIRED_PKGS[@]}"
-        ./init.sh
-    fi
-
 }
 
 ## MAIN
 
-CURDIR=$PWD
-REQUIRED_PKGS=(file git bc)
-install
+root_required
+
+if [[ $CURDIR != '/opt/miaou-bash' ]]; then
+    # download and fullfill /opt/miaou-bash, then run it from folder
+
+    if [[ -L /opt/miaou-bash ]]; then
+        /opt/miaou-bash/install.sh
+    else
+        rm -rf /opt/miaou-bash
+
+        push_directory "$(mktemp -d)"
+        wget $MAIN_TAR_GZ_URL
+        tar -xzf main.tar.gz
+        mv miaou-bash /opt/
+        pop_directory
+        rm -rf "$TEMP"
+
+        push_directory /opt/miaou-bash && ./install.sh
+
+    fi
+
+else
+    apt-get install -y "${REQUIRED_PKGS[@]}"
+    ./init.sh
+fi