#!/bin/bash

# Allows extended glob syntax in case statements
shopt -s extglob

NC='\033[0m'
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'

msg_info() {
    echo -e "${GREEN}[INFO] $1${NC}"
}

msg_warn() {
    echo -e "${YELLOW}[WARN] $1${NC}"
}

msg_error() {
    echo -e "${RED}[ERROR] $1${NC}"
}

print_help() {
    echo
    echo "dmenu_omnibar - a poor man's omnibar and bookmark manager (using dmenu)"
    echo
    echo "USAGE:"
    echo "    dmenu_omnibar -h|--help"
    echo "    dmenu_omnibar [-b|--browser <path>] [-B|--bookmarks <path>] [-s|--search-engine <url>]"
    echo
    echo "where:"
    echo "    -h | --help:"
    echo "        prints this help message."
    echo "    -b | --browser <path>"
    echo "        path to the executable used to open the selected link."
    echo "    -B | --bookmarks <path>"
    echo "        path to a file containing a list of bookmarks and"
    echo "        omnibar commands. See FORMAT below."
    echo "    -s | --search-engine <url>"
    echo "        default URL used when the input does not match any other"
    echo "        bookmark, URL or omnibar command. It should contain the"
    echo "        placeholder \"%s\" to be substituted with the query"
    echo "        provided by dmenu."
    echo
    echo "DMENU"
    echo "    dmenu will prompt for a bookmark from the provided list."
    echo "    If a match is found, the URL is selected. If a match is"
    echo "    not found the input is interpreted as follows:"
    echo "    1) as an URL if the provided input is an URL;"
    echo "    2) as a command if the input starts with \":\". Anything"
    echo "       following the command is interpreted as a query;"
    echo "    3) as a query to be submitted to the default search engine."
    echo 
    echo "    Note: sometimes an input partially matches an entry in the"
    echo "    bookmarks when you are aiming to one of the other behaviours"
    echo "    (e.g., opening an URL directly). You can submit only the"
    echo "    input text (without autoselection from the list of bookmarks)"
    echo "    with Shift-Enter."
    echo
    echo "FORMAT"
    echo "    The bookmarks file is assumed to have the following syntax."
    echo
    echo "    Lines containing a simple bookmark start with a sequence of"
    echo "    keywords, separated by one or more spaces, followed by the"
    echo "    URL of the bookmark."
    echo
    echo "    Lines containing omnibar commands start with a command"
    echo "    with a leading colon (e.g., \":s\", \":yt\") followed by"
    echo "    the URL containing the placeholder \"%s\" that will be"
    echo "    substituted with the provided query."
    echo
}

# Simple URL encoder
# The conversions are performed according to this table
#
#   https://docs.microfocus.com/OMi/10.62/Content/OMi/ExtGuide/ExtApps/URL_encoding.htm
#
# Consider using something like this:
#
#   https://gist.github.com/cdown/1163649
#
# for a more reliable approach.
urlencode() {
    sed 's|+|%2b|g' | sed 's|/|%2f|g'
}

omnisearch() {
    if grep -qs "^$1$" "$BOOKMARKS"
    then
        # Bookmark
        echo "$1" | awk '{ print $(NF) }'
    elif [[ "$1" =~ (https?://)?[A-Za-z0-9]+(\.[A-Za-z0-9]+)*\.[A-Za-z0-9]+(:[0-9]+)? ]]
    then
        # URL
        echo "$1"
    elif [[ "$1" =~ :[a-z]+\ .* ]]
    then
        # Omnisearch command
        CMD=$(echo "$1" | cut -s -d' ' -f1 -)
        SEARCH=$(echo "$1" | cut -s --complement -d' ' -f1 - | urlencode)
        URL=$(grep "$CMD" "$BOOKMARKS" | awk '{ print $(NF) }' | sed "s/%s/$SEARCH/g")
        echo "$URL"
    else
        # Default search query
        SEARCH=$(echo "$1" | urlencode)
        echo "$ENGINE" | sed "s/%s/$SEARCH/g"
    fi
}


BROWSER=`which firefox-bin`
BOOKMARKS=$HOME/.local/share/misc/bookmarks
ENGINE="https://search.dyamon.me/search?q=%s"

while [[ $# -gt 0 ]]; do
    arg="$1"
    case $arg in
        -h|--help)
            print_help
            exit 0
            ;;
        -b|--browser)
            if [[ $# -ge 2 ]]; then
                BROWSER=$2
                shift ; shift
            else
                msg_error "No value found for flag $arg!"
                print_help
                exit 2
            fi
            ;;
        -B|--bookmarks)
            if [[ $# -ge 2 ]]; then
                BOOKMARKS=$2
                shift ; shift
            else
                msg_error "No value found for flag $arg!"
                print_help
                exit 3
            fi
            ;;
        -s|--search-engine)
            if [[ $# -ge 2 ]]; then
                ENGINE="$2"
                shift ; shift
            else
                msg_error "No value found for flag $arg!"
                print_help
                exit 4
            fi
            ;;
        *)
            msg_error "$arg is not a valid flag!"
            print_help
            exit 1
            ;;
    esac
done

URL=$(grep -v ^: "$BOOKMARKS" | dmenu -l 10 -h 23)
[ -z "$URL" ] && exit 0
OMNIURL=$(omnisearch "$URL")

# Starts browser in background
"$BROWSER" "$OMNIURL" &