a small script for chezmoi to install missing dependencies

install_if_missing.sh

# Optional colorized output (disabled if NO_COLOR is set)
if [ -z "$NO_COLOR" ]; then
    COLOR_INFO="\033[1;34m"    # Bright Blue
    COLOR_SUCCESS="\033[1;32m" # Bright Green
    COLOR_WARN="\033[1;33m"    # Bright Yellow
else
    COLOR_INFO=""
    COLOR_SUCCESS=""
    COLOR_WARN=""
fi

# ---------------------------------
# install_if_missing
# ---------------------------------
#
# Usage:
#   install_if_missing \
#     "<check_command>" \
#     "<install_block>" \
#     "<description>" \
#     [<version_command>] \
#     [<expected_version>] \
#     [<post_install_block>]
#
# Arguments:
#   1. name:                Installable name
#   2. check_command:       A command or test that returns 0 if already installed.
#   3. install_block:       Quoted shell commands for installation.
#   4. version_command:     (Optional) Command to return current version (e.g., `go version | ...`).
#   5. expected_version:    (Optional) String to compare to version_command output.
#   6. post_install_block:  (Optional) Quoted shell commands to run after install.
#
# Examples:
#
#   check_bash_it() { [ -d "$HOME/.bash_it/" ]; }
#   install_bash_it() {
#       git clone --depth=1 https://github.com/Bash-it/bash-it.git ~/.bash_it
#       source $HOME/.bash_it/install.sh -sn
#       rm -rf ~/.oh-my-bash
#   }
#   install_if_missing "oh-my-bash" check_bash_it "" "" install_bash_it ""
#
#   GO_VERSION="1.24.1"
#   check_go() { command -v go &>/dev/null; }
#   version_go() { go version | awk '{print $3}' | sed 's/go//'; }
#   install_go() {
#       wget https://go.dev/dl/go$GO_VERSION.linux-amd64.tar.gz
#       sudo rm -rf /usr/local/go
#       sudo tar -C /usr/local -xzf go$GO_VERSION.linux-amd64.tar.gz
#       rm -f go$GO_VERSION.linux-amd64.tar.gz
#       go install github.com/dkorunic/betteralign/cmd/betteralign@latest
#       go install github.com/yoheimuta/protolint/cmd/protolint@latest
#       go install github.com/bufbuild/buf/cmd/buf@latest
#       go install github.com/go-task/task/v3/cmd/task@latest
#       CGO_ENABLED=1 go install -tags extended github.com/gohugoio/hugo@latest
#   }
#   install_if_missing "go" check_go version_go "$GO_VERSION" install_go ""
install_if_missing() {
    local name="$1"
    local check_func="$2"
    local version_func="$3"
    local expected_version="$4"
    local install_func="$5"
    local post_install_func="$6"

    if ! $check_func; then
        echo -e "${COLOR_INFO}$name not found. Installing..."
        $install_func
        [ -n "$post_install_func" ] && $post_install_func
    elif [ -n "$expected_version" ] && [ -n "$version_func" ]; then
        local actual_version="$($version_func)"
        if [ "$actual_version" != "$expected_version" ]; then
            echo -e "${COLOR_WARN}$name version mismatch. Reinstalling..."
            $install_func
            echo -e "${COLOR_SUCCESS}$name installed."
            [ -n "$post_install_func" ] && $post_install_func
        else
            echo -e "${COLOR_SUCCESS}$name is already installed and up-to-date."
        fi
    else
        echo -e "${COLOR_SUCCESS}$name is already installed."
    fi
}