feat: Add install.sh

Author: marverix

.editorconfig

@@ -0,0 +1,16 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_size = 4
+indent_style = space
+insert_final_newline = true
+max_line_length = 120
+tab_width = 4
+
+[{gah,*.sh,*.bash,*.bats}]
+indent_style = tab
+
+[*.md]
+indent_size = 2

install.sh

@@ -0,0 +1,78 @@
+#!/usr/bin/env bash
+
+# gah! installer
+#
+# @author Marek `marverix` Sierociński
+# @license GNU GPLv3
+
+# Pipeline mode
+set -e
+
+#--------------------------------------------------
+#region Utils
+function print_blue() {
+	echo -e "\033[0;34m$1\033[0m"
+}
+
+function print_green() {
+	echo -e "\033[0;32m$1\033[0m"
+}
+
+function print_yellow() {
+	echo -e "\033[0;33m$1\033[0m"
+}
+
+function throw_error() {
+	echo -e "\033[0;31mError: $2\033[0m" >&2
+	exit $1
+}
+
+function require_command() {
+	print_blue "Checking if $1 is installed..."
+	if ! command -v $1 2>&1 >/dev/null; then
+		throw_error 2 "$1 is not installed"
+	fi
+	print_green "OK"
+}
+
+#endregion
+#--------------------------------------------------
+
+# Require that bash is at least 4.0
+print_blue "Checking if Bash 4.0 or higher is installed..."
+if [ "${BASH_VERSINFO[0]}" -lt 4 ]; then
+	throw_error 1 "Bash 4.0 or higher is required"
+fi
+print_green "OK"
+
+# Check if required commands are installed
+require_command tar
+require_command unzip
+require_command curl
+require_command jq
+
+# Ensure ~/.local/bin exists
+print_blue "Ensuring ~/.local/bin exists..."
+mkdir -p ~/.local/bin
+print_green "OK"
+
+# Check if ~/.local/bin is in PATH
+print_blue "Checking if ~/.local/bin is in PATH..."
+if [[ ":$PATH:" != *":$HOME/.local/bin:"* ]]; then
+	print_yellow "WARNING: ~/.local/bin is not in PATH. gah will not work if ~/.local/bin is not in PATH."
+else
+	print_green "OK, looks good!"
+fi
+
+# Check gah latest tag
+print_blue "Checking latest gah release..."
+tag=$(curl -s https://api.github.com/repos/marverix/gah/releases/latest | jq -r '.tag_name')
+print_green "OK, latest tag is $tag"
+
+# Download gah! script
+print_blue "Downloading gah $tag script..."
+curl -sL https://raw.githubusercontent.com/marverix/gah/refs/tags/$tag/gah -o ~/.local/bin/gah
+chmod +x ~/.local/bin/gah
+print_green "OK"
+
+print_green "Done!"