#!/bin/sh

# Copyright (c) 2022–2023 Emma Tebibyte
# SPDX-License-Identifier: AGPL-3.0-or-later
#
# This program is free software: you can redistribute it and/or modify it under
# the terms of the GNU Affero General Public License as published by the Free
# Software Foundation, either version 3 of the License, or (at your option) any
# later version.
# 
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
# details.
#
# You should have received a copy of the GNU Affero General Public License along
# with this program. If not, see https://www.gnu.org/licenses/.

set -e

argv0="$0"

# check if usage is valid
if test -z "$1"; then
  printf "Usage: %s [resource...]\n" "$argv0" 1>&2
  exit 64 # sysexits(3) EX_USAGE
fi

for dep in \
  curl \
  handlr \
  tomcat
do
  if ! command -v "$dep" >/dev/null 2>&1; then
    printf "%s: Missing dependency: %s(1)\n" "$argv0" "$dep" 1>&2
    exit 69 # sysexits(3) EX_UNAVAILABLE
  fi
done

# check if we have a BROWSER
if test -z "$BROWSER"; then
  printf "%s: \$BROWSER not filled.\n" "$argv0" 1>&2
  exit 71 # sysexits(3) EX_OSERR
fi

while test -n "$1"; do
  URL="$1"

  # use curl(1) to write out the request header's content_type,
  # strip everything after the first semicolon,
  # chop off any weird whitespace remnants
  MIME="$(curl -Ls -o /dev/null -w '%{content_type}' "$1" | sed 's/\;.*//' \
    | xargs echo)"

  # get the pattern for the extensions to MATCH
  MATCH="$(printf "%s\n" "$URL" | sed -ne 's/^h.\+\/\///p' \
    | sed -e 's/\/.*\+//g')"
  
  # run through MIME extensions
  for file in \
    "$XDG_DATA_HOME"/xdg-sanity/*-mime.toml \
    /usr/share/xdg-sanity/*-mime.toml \
    /usr/local/share/xdg-sanity/*-mime.toml
  do
    if test -e "$file"; then
      i=$(tomcat replace.urls "$file" | sed 's/	/\n/g' | wc -l)
      while ! [ "$i" = 0 ]; do
        if [ "$MATCH" = "$(tomcat replace.urls["$i"] "$file")" ]; then
          MIME="$(tomcat with.mime "$file")"
        fi
        i="$(printf "%s-1\n" "$i" | bc)"
      done
    fi
  done

  # and the replace extensions
  for file in \
    "$XDG_DATA_HOME"/xdg-sanity/*-replace.toml \
    /usr/share/xdg-sanity/*-replace.toml \
    /usr/local/share/xdg-sanity/*-replace.toml
  do
    if test -e "$file"; then
      i="$(tomcat replace.urls "$file" | sed 's/	/\n/g' | wc -l)"
      while ! [ "$i" = 0 ]; do
        if [ "$MATCH" = "$(tomcat replace.urls["$i"] "$file")" ]; then
          URL="$(tomcat with.url "$file")"
        fi
        i="$(printf "%s-1\n" "$i" | bc)"
      done
    fi
  done

  # these commands may fail; this is intentional
  if [ "$MIME" = "text/html" ]; then
    "$BROWSER" "$URL"
  else
    handlr launch "$MIME" -- "$URL"
  fi
  shift
done

exit 0