#!/usr/bin/env bash
# shellcheck disable=2016
readonly dependency=("samme/base16-styles")
readonly app="styles"

readonly path="$1"
readonly package="$2"
readonly theme="$3"
readonly permanent="$4"

stylesheet="$HOME/.config/qutebrowser/stylesheets/stylesheet.css"
styletemplate="css-template.css"

## Main Entrypoint
#
#  Finds the right theme template file and starts theme
#  switching and, if necessary, permanent setting processes.
main() {
  dbg_msg $app "Starting Processor"
  tfile="$path/$package/scss/base16-$theme.scss"

  if ! file_exists "$tfile"; then
    dbg_msg $app "error" "Theme template $theme not found in package $package"
    exit 1
  fi

  if [[ "$permanent" == "true" ]]; then save; fi
  theme

  dbg_msg $app "Processor Done"
}

## Theme switcher
#
#  Makes sure that if any application instance is
#  currently running, it switches to new theme.
theme() {
  dbg_msg $app "Switching theme"
  # make sure qutebrowser is running
  pgrep qutebrowser >/dev/null || {
    dbg_msg $app "warn" "No instance running, not switching theme"
    return
  }
  qutebrowser --loglevel error ":set content.user_stylesheets $stylesheet"
  dbg_msg $app "Successfully switched theme"
}

## Theme setter
#
#  Takes care of permanently writing the desired
#  base16 theme into application settings.
save() {
  dbg_msg $app "Saving theme"

  fix_placeholders

  if [ ! -f "$stylesheet" ]; then
    mkdir -p "$(dirname "$stylesheet")" || dbg_msg $app error "Could not create theme folder for $stylesheet"
    dbg_msg $app "Theme folder for $stylesheet did not exist yet so I created it"
  fi

  echo "$newsheet" >"$stylesheet"
  dbg_msg $app "Saved theme to $stylesheet"
}

fix_placeholders() {
  local base00 base01 base02 base03 base04 base05 base06 base07 base08 base09 base0A base0B base0C base0D base0E base0F
  base00=$(grep -e "\$base00" "$tfile" | sed -e 's/^$base00: \(#[[:alnum:]]\+\);$/\1/')
  base01=$(grep -e "\$base01" "$tfile" | sed -e 's/^$base01: \(#[[:alnum:]]\+\);$/\1/')
  base02=$(grep -e "\$base02" "$tfile" | sed -e 's/^$base02: \(#[[:alnum:]]\+\);$/\1/')
  base03=$(grep -e "\$base03" "$tfile" | sed -e 's/^$base03: \(#[[:alnum:]]\+\);$/\1/')
  base04=$(grep -e "\$base04" "$tfile" | sed -e 's/^$base04: \(#[[:alnum:]]\+\);$/\1/')
  base05=$(grep -e "\$base05" "$tfile" | sed -e 's/^$base05: \(#[[:alnum:]]\+\);$/\1/')
  base06=$(grep -e "\$base06" "$tfile" | sed -e 's/^$base06: \(#[[:alnum:]]\+\);$/\1/')
  base07=$(grep -e "\$base07" "$tfile" | sed -e 's/^$base07: \(#[[:alnum:]]\+\);$/\1/')
  base08=$(grep -e "\$base08" "$tfile" | sed -e 's/^$base08: \(#[[:alnum:]]\+\);$/\1/')
  base09=$(grep -e "\$base09" "$tfile" | sed -e 's/^$base09: \(#[[:alnum:]]\+\);$/\1/')
  base0A=$(grep -e "\$base0A" "$tfile" | sed -e 's/^$base0A: \(#[[:alnum:]]\+\);$/\1/')
  base0B=$(grep -e "\$base0B" "$tfile" | sed -e 's/^$base0B: \(#[[:alnum:]]\+\);$/\1/')
  base0C=$(grep -e "\$base0C" "$tfile" | sed -e 's/^$base0C: \(#[[:alnum:]]\+\);$/\1/')
  base0D=$(grep -e "\$base0D" "$tfile" | sed -e 's/^$base0D: \(#[[:alnum:]]\+\);$/\1/')
  base0E=$(grep -e "\$base0E" "$tfile" | sed -e 's/^$base0E: \(#[[:alnum:]]\+\);$/\1/')
  base0F=$(grep -e "\$base0F" "$tfile" | sed -e 's/^$base0F: \(#[[:alnum:]]\+\);$/\1/')

  # get directory of calling file
  local DIR="${BASH_SOURCE%/*}"
  if [[ ! -d "$DIR" ]]; then DIR="$PWD"; fi

  newsheet=$(sed -e "s/%base00%/$base00/;s/%base01%/$base01/;s/%base02%/$base02/;s/%base03%/$base03/;s/%base04%/$base04/;s/%base05%/$base05/;s/%base06%/$base06/;s/%base07%/$base07/;s/%base08%/$base08/;s/%base09%/$base09/;s/%base0A%/$base0A/;s/%base0B%/$base0B/;s/%base0C%/$base0C/;s/%base0D%/$base0D/;s/%base0E%/$base0E/;s/%base0F%/$base0F/" "$DIR/$styletemplate")
}

## Theme includer
#
#  Makes sure that theme is actually included in
#  default application startup routine.
#  This is the most invasive step of theming since it
#  rewrites within existing configuration files.
include() {
  local qt_dir="$1"
  dbg_msg $app "Including theme in configuration"

  if file_exists "$qt_dir/config.py"; then
    line_exists_or_append "$qt_dir/config.py" "config.source('colorscheme.py')"
    dbg_msg $app "Successfully included theme in configuration"
  else
    dbg_msg $app "warn" "No default configuration file found"
  fi
}

# Safe sourcing: https://stackoverflow.com/a/12694189
DIR="${BASH_SOURCE%/*}"
if [[ ! -d "$DIR" ]]; then DIR="$PWD"; fi
# shellcheck source=utilities.sh
. "$DIR/utilities.sh"
## Dependency Checker
#
#  Makes sure the processor is called for the correct
#  base16 package, or refuses to run if it is not.
if printf '%s\n' "${dependency[@]}" | grep -q -P "^$package$"; then
  main
else
  dbg_msg $app "error" "Processor does not work for package $package"
fi