Add convenience download script

Add script to download the latest release version from GitHub.

scripts/download-latest.sh

@@ -0,0 +1,78 @@
+#!/usr/bin/env bash
+
+# Copyright © 2018 Matthias Diester
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+set -euo pipefail
+
+if ! hash curl 2>/dev/null; then
+  echo -e 'Required tool \033[1mcurl\033[0m is not installed.'
+  exit 1
+fi
+
+if ! hash jq 2>/dev/null; then
+  echo -e 'Required tool \033[1mjq\033[0m is not installed.'
+  exit 1
+fi
+
+if [[ "$(uname -m)" != "x86_64" ]]; then
+  echo -e "Unsupported machine type \\033[1m$(uname -m)\\033[0m: Please check \\033[4;94mhttps://api.github.com/repos/HeavyWombat/ytbx/releases\\033[0m manually"
+  exit 1
+fi
+
+if [[ $# -eq 0 ]]; then
+  # Find the latest ytbx version using the GitHub API
+  SELECTED_TAG="$(curl --silent --location https://api.github.com/repos/HeavyWombat/ytbx/releases | jq --raw-output '.[0].tag_name')"
+else
+  # Use provided argument as tag to download
+  SELECTED_TAG="$1"
+fi
+
+SYSTEM_UNAME="$(uname | tr '[:upper:]' '[:lower:]')"
+
+# Find a suitable install location
+if [[ -w /usr/local/bin ]]; then
+  TARGET_DIR=/usr/local/bin
+
+elif [[ -w "$HOME/bin" ]] && grep -q -e "$HOME/bin" -e '\~/bin' <<<"$PATH"; then
+  TARGET_DIR=$HOME/bin
+
+else
+  echo -e "Unable to determine a writable install location. Make sure that you have write access to either \\033[1m/usr/local/bin\\033[0m or \\033[1m$HOME/bin\\033[0m and that is in your PATH."
+  exit 1
+fi
+
+# Download and install ytbx
+case "${SYSTEM_UNAME}" in
+  darwin | linux)
+    TARGET_FILE="${TARGET_DIR}/ytbx"
+    DOWNLOAD_URI="https://github.com/HeavyWombat/ytbx/releases/download/${SELECTED_TAG}/ytbx-${SYSTEM_UNAME}-amd64"
+
+    echo -e "Downloading \\033[4;94m${DOWNLOAD_URI}\\033[0m to \\033[1m${TARGET_DIR}\\033[0m"
+    if (curl --progress-bar --location "${DOWNLOAD_URI}" --output "${TARGET_FILE}" && chmod a+rx "${TARGET_FILE}"); then
+      echo -e "\\nSuccessfully installed \\033[1m${TARGET_FILE}\\033[0m\\n"
+    fi
+    ;;
+
+  *)
+    echo "Unsupported operating system: ${SYSTEM_UNAME}"
+    exit 1
+    ;;
+esac