# General environment settings.
export XDG_CACHE_HOME="${XDG_CACHE_HOME:-$HOME/.cache}"
export XDG_CONFIG_HOME="${XDG_CONFIG_HOME:-$HOME/.config}"
export XDG_DATA_HOME="${XDG_DATA_HOME:-$HOME/.local/share}"

export LANG="en_US.UTF-8"
export LANGUAGE="en_US"
export LC_ALL="en_US.UTF-8"
export LC_CTYPE="en_US.UTF-8"
export LC_COLLATE="C"

export INPUTRC="$XDG_CONFIG_HOME/readline/inputrc"
export LESS="-i -j.49 -M -R -z-2"
export LESSHISTFILE="$XDG_DATA_HOME/less/history"
export LESSHISTSIZE=1000
export LOCAL_PREFIX="/usr/local"
export PAGER=less
export PYTHONSTARTUP="$XDG_CONFIG_HOME/python/startup.py"

have() {
  command -v "$1" >/dev/null 2>&1
}

# Prevent path_helper from messing with the PATH when starting tmux.
#
# Clearing PATH before path_helper executes (from /etc/profile) will prevent it
# from prepending the default PATH to our (previously) chosen PATH, and will
# allow the rest of this file to set up PATH and MANPATH correctly.
#
#   For details see: https://superuser.com/a/583502
#
[ "$(uname -s)" = "Darwin" ] && { PATH=""; source /etc/profile; }

# Prepend $2 to variable $1 using $3 as separator, but only if $2 is not already
# contained in $1. This is useful for prepending to PATH while avoiding
# duplicates.
prepend_unique() {
  local var="$1"
  local new="$2"
  local sep="${3-:}"  # Default separator is colon.
  local old="${(P)var}"

  case "${sep}${old}${sep}" in
    *"${sep}${new}${sep}"*)  # Skip duplicate.
      ;;
    "${sep}${sep}")  # Variable was empty, set without separator.
      typeset -g $var="${new}"
      ;;
    *) # Prepend with separator.
      typeset -g $var="${new}${sep}${old}"
      ;;
  esac
}

# Add custom bin dirs to PATH if they exist and are not already in PATH.
while read -r dir; do
  [ -d "$dir" ] && prepend_unique PATH "${dir}"
done <<EOL
  $LOCAL_PREFIX/bin
  $LOCAL_PREFIX/opt/curl/bin
  $LOCAL_PREFIX/opt/make/libexec/gnubin
  $LOCAL_PREFIX/opt/findutils/libexec/gnubin
  $LOCAL_PREFIX/opt/gnu-sed/libexec/gnubin
  $LOCAL_PREFIX/opt/gnu-tar/libexec/gnubin
  $LOCAL_PREFIX/opt/grep/libexec/gnubin
  $LOCAL_PREFIX/opt/coreutils/libexec/gnubin
  $HOME/.local/bin
  $HOME/.bin
EOL
export PATH

# Prepend custom man directories to MANPATH if they exist, so that we get
# correct man page entries when multiple versions of a command are
# available.
have manpath && MANPATH="$(unset MANPATH; manpath)"
while read -r dir; do
  [ -d "$dir" ] && prepend_unique MANPATH "${dir}"
done <<EOL
  $LOCAL_PREFIX/share/man
  $LOCAL_PREFIX/opt/curl/share/man
  $LOCAL_PREFIX/opt/make/libexec/gnuman
  $LOCAL_PREFIX/opt/findutils/libexec/gnuman
  $LOCAL_PREFIX/opt/gnu-sed/libexec/gnuman
  $LOCAL_PREFIX/opt/gnu-tar/libexec/gnuman
  $LOCAL_PREFIX/opt/grep/libexec/gnuman
  $LOCAL_PREFIX/opt/coreutils/libexec/gnuman
  $HOME/.local/share/man
EOL
export MANPATH

unset dir

# These checks have to be done after PATH manipulation above so we can find
# installed programs if they are in the added paths.

have nvim && EDITOR="nvim"
[ -z $EDITOR ] && have vim && EDITOR="vim"
[ -z $EDITOR ] && have vi && EDITOR="vi"
[ -n $EDITOR ] && export EDITOR

have brew && {
  export HOMEBREW_NO_ANALYTICS=1
  export HOMEBREW_NO_AUTO_UPDATE=1
}

have dotnet && {
  export DOTNET_CLI_TELEMETRY_OPTOUT=1
  export DOTNET_NOLOGO=1
}

# Set $DISPLAY if running in WSL and an Xserver is reachable
#
# How to configure Windows Firewall for Xserver: https://skeptric.com/wsl2-xserver/
# How to check if running in WSL: https://stackoverflow.com/a/61014411
if [ -n "$(uname -r | sed -n 's/.*\( *Microsoft *\).*/\1/ip')" ]; then
  xdisplay="$(awk '/nameserver/ {print $2; exit}' /etc/resolv.conf 2>/dev/null):0.0"
  have xset && if DISPLAY="$xdisplay" timeout '0.2s' xset q >/dev/null 2>&1; then
    export DISPLAY="$xdisplay"
    export LIBGL_ALWAYS_INDIRECT=1
  fi
  unset xdisplay
fi