dot_sh_functions

# SPDX-FileCopyrightText: Chris Wilson <christopher.david.wilson@gmail.com>
#
# SPDX-License-Identifier: MIT

# Shell functions for Bourne-compatible shells

# shellcheck shell=sh

# ------------------------------------------------------------------------------
# Functions
# ------------------------------------------------------------------------------

# Checks if a command exists (works for executables, builtins, aliases, and
# functions)
# https://stackoverflow.com/a/34143401
command_exists ()
{
    command -v "$1" >/dev/null 2>&1
}

# Checks if an executable exists (doesn't work for )
# https://stackoverflow.com/a/26759734
executable_exists ()
(
    cmd=$(command -v "$1")
    [ -x "${cmd}" ]
)

# https://stackoverflow.com/a/18434831
os_type ()
{
    uname | tr '[:upper:]' '[:lower:]'
}

# Macs with Apple Silicon (arm64) can run executables compiled for Intel
# (x86_64) via the Rosetta translation process.  See this link for more details:
# https://developer.apple.com/documentation/apple-silicon/about-the-rosetta-translation-environment
case $(os_type) in
    darwin*)
        # https://stackoverflow.com/questions/65259300/detect-apple-silicon-from-command-line#comment124415881_65259353
        # https://stackoverflow.com/a/37073155
        cpu_is_apple_silicon ()
        (
            cpu=$(sysctl -n machdep.cpu.brand_string)
            [ "${cpu#Apple}" != "${cpu}" ]
        )

        cpu_is_intel ()
        (
            cpu=$(sysctl -n machdep.cpu.brand_string)
            [ "${cpu#Intel}" != "${cpu}" ]
        )

        # https://indiespark.top/software/detecting-apple-silicon-shell-script/
        shell_is_translated ()
        (
            translated=$(sysctl -n sysctl.proc_translated)
            [ "${translated}" = "1" ]
        )

        shell_is_native ()
        (
            translated=$(sysctl -n sysctl.proc_translated)
            [ "${translated}" = "0" ]
        )
        ;;
    *)
        ;;
esac