#!/bin/bash 
### arguments:
# $1: the URI we're starting
# $2: the "referer" of the URI we're starting.
### requirements:
# getsrv, urimatch, urijoin, uricut, some-way-to-ask-the-user-for-a-line (dmenu by default)
# getsrv tries dig and host, you only need one or the other.
##might have to configure me.
ASKUSER="choose"

check=dont

uristart_config=~/.config/uristart.conf

usage() {
    printf "usage: uristart [-v|--verbose|-h|--help|-c|--check] [-f|--config file] URI\n"
}

while case "$1" in
  --help|-h)
    usage
    exit 0
    ;;
  --verbose|-v)
    verbose=verbose
    ;;
  --config|-f)
    shift
    export uristart_config="$1"
    ;;
  --check|-c)
    check=check
    ;;
  *)
    break
    ;;
esac;do shift;done

if [ "$verbose" ];then
  echo "uristart: verbose:" "$verbose"
  echo "uristart: config:" "$uristart_config" >&2
  echo "uristart: check:" "$check" >&2
  echo "uristart: other:" "$@" >&2
fi

if [ ! "$@" ];then
  usage >&2 #to stderr because it is an error to not have any extra args to process
  exit 1
fi

if [ ! -e "$uristart_config" ];then
  printf "uristart: missing config file: %s\n" "$uristart_config" >&2
  exit 1
fi

uri="${1}"
scheme="$(printf "%s\n" "$uri" | uricut -s)"

line="$(urigetline "$uri")"

### if we do not have a port, we are going to try to get it from their srv records.
if printf "%s\n" "$uri" | urimatch nP >/dev/null;then
  proto="$(grep ^"$scheme"'\s' /etc/services | tr ' ' '\t' | tr -s '\t ' | cut -f2 | cut -d/ -f2 | head -n1)"
  if [ ! "$proto" ]; then
    proto=tcp
  fi
  uri="$(cat <(printf "%s\n" "$uri" | uricut) \
             <(getsrv $(printf "%s\n" "$uri" | uriprintf '%s '"$proto"' %d' | cut -d+ -f2-) 2>&- | tr ':' ' ' | sed 's/ /_port: /' | sed 's/^/domain: /' | tr _ '\n') \
          | urijoin 2>/dev/null)"
  [ "$verbose" ] && printf "uristart: srv (%s) modified uri: %s\n" "$proto" "$uri" >&2
fi

### if they do not have srv records, fall-back to /etc/services
if printf "%s\n" "$uri" | urimatch nP >/dev/null;then #if we *still* don't have a port
  uri="$(cat <(printf "%s\n" "$uri" | uricut) \
             <(grep ^"$scheme"'\s' /etc/services | tr ' ' '\t' | tr -s '\t' | cut -f2 | cut -d/ -f1 | head -n1 | sed 's/^/port: /') \
          | urijoin 2>/dev/null)"
  [ "$verbose" ] && printf "uristart: getent modified uri: %s\n" "$uri" >&2
fi

### ask the user for a pipeline for starting these URIs if there isn't a pipeline already in the config.
[ "$verbose" ] && echo "uristart: the uri we're using: $uri" >&2
if [ "$line" = "" ];then
  line="$(printf "" | $ASKUSER "protocol scheme (${scheme}) not configured yet. enter new pipeline to use:")"
  if [ "$line" = "" ];then
    echo "uristart: user noped on entering new pipeline" >&2
    exit 1
  fi
  printf '%s:\t%s\n' "${scheme}" "${line}" >> ~/.config/uristart.conf
fi

### log the uri if it isn't logged already.
if [ -w ~/.cache/uristart.log ];then #only log if it is writable
  if ! cut '-d ' -f1 ~/.cache/uristart.log | grep -Fx "$uri" 2>&1 >/dev/null;then #only log URIs that aren't already listed
    if [ "$2" ];then
      printf "%s %s\n" "$uri" "$2" >> ~/.cache/uristart.log
    else
      printf "%s\n" "$uri" >> ~/.cache/uristart.log
    fi
  fi
else
  [ "$verbose" ] && printf "uristart: ~/.cacche/uristart.log is not writable. not logging.\n" >&2
fi

### do the magic
if [ "$check" = "check" ];then
  printf "%s\n" "$(printf "%s\n" "$uri" | sed 's/'\''/'\''\\'\'''\''/g' | uriprintf "$line")"
else
  eval "$(printf "%s\n" "$uri" | sed 's/'\''/'\''\\'\'''\''/g' | uriprintf "$line")"
fi