#!/bin/sh
#---------------------------------------------
#   xdg-settings
#
#   Utility script to get various settings from the desktop environment.
#
#   Refer to the usage() function below for usage.
#
#   Copyright 2009, Google Inc.
#
#   LICENSE:
#
#---------------------------------------------

manualpage()
{
cat << '_MANUALPAGE'
_MANUALPAGE
}

usage()
{
cat << '_USAGE'
_USAGE
}

#@xdg-utils-common@

check_desktop_filename()
{
    case "$1" in
      */*)
        exit_failure_syntax "invalid application name"
        ;;
      *.desktop)
        return
        ;;
      *)
        exit_failure_syntax "invalid application name"
        ;;
    esac
}

# {{{ default browser
# {{{ utility functions

# In order to remove an application from the automatically-generated list of
# applications for handling a given MIME type, the desktop environment may copy
# the global .desktop file into the user's .local directory, and remove that
# MIME type from its list. In that case, we must restore the MIME type to the
# application's list of MIME types before we can set it as the default for that
# MIME type. (We can't just delete the local version, since the user may have
# made other changes to it as well. So, tweak the existing file.)
# This function is hard-coded for text/html but it could be adapted if needed.
fix_local_desktop_file()
{
    if test -z "$2" ; then
        MIME="text/html"
    else
        MIME="$2"
    fi
    apps="${XDG_DATA_HOME:-$HOME/.local/share}/applications"
    # No local desktop file?
    [ ! -f "$apps/$1" ] && return
    MIMETYPES="`grep "^MimeType=" "$apps/$1" | cut -d= -f 2-`"
    case "$MIMETYPES" in
      $MIME\;*|*\;$MIME\;*|*\;$MIME\;|*\;$MIME)
        # Already has the mime-type? Great!
        return 0
        ;;
    esac

    # Add the mime-type to the list
    temp="`mktemp "$apps/$1.XXXXXX"`" || return
    grep -v "^MimeType=" "$apps/$1" >> "$temp"
    echo "MimeType=$MIME;$MIMETYPES" >> "$temp"

    oldlines="`wc -l < "$apps/$1"`"
    newlines="`wc -l < "$temp"`"
    # The new file should have at least as many lines as the old.
    if [ $oldlines -le $newlines ]; then
        mv "$temp" "$apps/$1"
        # This can take a little bit to get noticed.
        sleep 4
    else
        rm -f "$temp"
        return 1
    fi
}

# }}} utility functions
# {{{ MIME utilities

xdg_mime_fixup()
{
    # xdg-mime may use ktradertest, which will fork off a copy of kdeinit if
    # one does not already exist. It will exit after about 15 seconds if no
    # further processes need it around. But since it does not close its stdout,
    # the shell (via grep) will wait around for kdeinit to exit. If we start a
    # copy here, that copy will be used in xdg-mime and we will avoid waiting.
    if [ "$DE" = kde ] && [ -z "$XDG_MIME_FIXED" ]; then
        ktradertest text/html Application > /dev/null 2>&1
        # Only do this once, as we only need it once.
        XDG_MIME_FIXED=yes
    fi
}

get_browser_mime()
{
    if test -z "$1" ; then
        MIME="text/html"
    else
        MIME="$1"
    fi
    xdg_mime_fixup
    xdg-mime query default "$MIME"
}

set_browser_mime()
{
    xdg_mime_fixup
    if test -z "$2" ; then
        MIME="text/html"
    else
        MIME="$2"
    fi
    orig="`get_browser_mime $MIME`"
    # Fixing the local desktop file can actually change the default browser all
    # by itself, so we fix it only after querying to find the current default.
    fix_local_desktop_file "$1" "$MIME" || return
    mkdir -p "${XDG_DATA_HOME:-$HOME/.local/share}/applications"
    xdg-mime default "$1" "$MIME" || return
    if [ x"`get_browser_mime $MIME`" != x"$1" ]; then
        # Put back the original value
        xdg-mime default "$orig" "$MIME"
        exit_failure_operation_failed
    fi
}

# }}} MIME utilities
# {{{ KDE utilities

# Reads the KDE configuration setting, compensating for a bug in some versions of kreadconfig.
read_kde_config()
{
    configfile="$1"
    configsection="$2"
    configkey="$3"
    if [ x"${KDE_SESSION_VERSION}" = x"5" ]; then
        application="`kreadconfig5 --file $configfile --group $configsection --key $configkey`"
    elif [ x"${KDE_SESSION_VERSION}" = x"6" ]; then
        application="`kreadconfig6 --file $configfile --group $configsection --key $configkey`"
    else
        application="`kreadconfig --file $configfile --group $configsection --key $configkey`"
    fi
    if [ x"$application" != x ]; then
        echo "$application"
    else
      if [ x"${KDE_SESSION_VERSION}" = x"4" ]; then
        # kreadconfig in KDE 4 may not notice Key[$*]=... localized settings, so
        # check by hand if it didn't find anything (oddly kwriteconfig works
        # fine though).
        configfile_dir=`kde${KDE_SESSION_VERSION}-config --path config  | cut -d ':' -f 1`
        configfile_path="$configfile_dir/$configfile"
        [ ! -f "$configfile_path" ] && return
        # This will only take the first value if there is more than one.
        grep "^$configkey"'\[$[^]=]*\]=' "$configfile_path" | head -n 1 | cut -d= -f 2-
      fi
    fi
}

# }}} KDE utilities
# {{{ KDE

# Resolves the KDE browser setting to a binary: if prefixed with !, simply removes it;
# otherwise, uses desktop_file_to_binary to get the binary out of the desktop file.
resolve_kde_browser()
{
    [ -z "$browser" ] && return
    case "$browser" in
      !*)
        echo "${browser#!}"
        ;;
      *)
        desktop_file_to_binary "$browser"
        ;;
    esac
}

# Does the opposite of resolve_kde_browser: if prefixed with !, tries to find a desktop
# file corresponding to the binary, otherwise just returns the desktop file name.
resolve_kde_browser_desktop()
{
    [ -z "$browser" ] && return
    case "$browser" in
      !*)
        desktop="`binary_to_desktop_file "${browser#!}"`"
        basename "$desktop"
        ;;
      *)
        echo "$browser"
        ;;
    esac
}

read_kde_browser()
{
    # since Plasma >= 5.19
    ret=`get_browser_mime "x-scheme-handler/http"`
    if [ -z "$ret" ]; then
        # older Plasma versions
        ret=`read_kde_config kdeglobals General BrowserApplication`
    fi
    
    echo $ret
}

get_browser_kde()
{
    browser="`read_kde_browser`"
    if [ x"$browser" = x ]; then
        # No explicit default browser; KDE will use the MIME type text/html.
        get_browser_mime
    else
        resolve_kde_browser_desktop
    fi
}

check_browser_kde()
{
    check="`desktop_file_to_binary "$1"`"
    if [ -z "$check" ]; then
        echo no
        exit_success
    fi
    browser="`read_kde_browser`"
    binary="`resolve_kde_browser`"

    # The browser may contain a relative entry to the binary starting with !
    case "$browser" in !*)
        # get the full path
        browser="`binary_to_desktop_file ${browser#!}`"
        binary="`desktop_file_to_binary $browser`"
    esac

    # Because KDE will use the handler for MIME type text/html if this value
    # is empty, we allow either the empty string or a match to $check here.
    if [ x"$binary" != x ] && [ x"$binary" != x"$check" ]; then
        echo no
        exit_success
    fi
    browser="`get_browser_mime`"
    binary="`desktop_file_to_binary "$browser"`"
    if [ x"$binary" != x"$check" ]; then
        echo no
        exit_success
    fi
    echo yes
    exit_success
}

set_browser_kde()
{
    # Set the default browser.
    for protocol in http https; do
        set_browser_mime "$1" "x-scheme-handler/$protocol" || return
    done

    # Plasma < 5.19
    set_browser_mime "$1" "text/html" || return
    if [ x"${KDE_SESSION_VERSION}" = x"5" ]; then
        kwriteconfig5 --file kdeglobals --group General --key BrowserApplication "$1"
    elif [ x"${KDE_SESSION_VERSION}" = x"6" ]; then
        kwriteconfig6 --file kdeglobals --group General --key BrowserApplication "$1"
    else
        kwriteconfig --file kdeglobals --group General --key BrowserApplication "$1"
    fi
}

# }}} KDE
# {{{ Deepin

read_deepin_browser()
{
    dbus-send --print-reply=literal --dest=com.deepin.daemon.Mime /com/deepin/daemon/Mime com.deepin.daemon.Mime.GetDefaultApp string:"x-scheme-handler/http" | jq -r '.Id'
}

get_browser_deepin()
{
    browser="$(read_deepin_browser)"
    if [ -n "$browser" ]; then
        echo "$browser"
        exit_success
    else
        exit_failure_operation_failed
    fi
}

check_browser_deepin()
{
    if [ "$(read_deepin_browser)" = "$1" ]; then
        exit_success
    else
        exit_failure_operation_failed
    fi
}

set_browser_deepin()
{
    xdg-mime default "$1" x-scheme-handler/http x-scheme-handler/ftp x-scheme-handler/https text/html text/xml text/xhtml_xml text/xhtml+xml
    if [ $? -ne 0 ]; then
        exit_failure_operation_failed
    else
        exit_success
    fi
}

# }}} Deepin
# {{{ GNOME

get_browser_gnome()
{
    binary="`gconftool-2 --get /desktop/gnome/applications/browser/exec | first_word`"
    if [ x"$binary" = x ]; then
        # No default browser; GNOME might use the MIME type text/html.
        get_browser_mime
    else
        # gconftool gives the binary (maybe with %s etc. afterward),
        # but we want the desktop file name, not the binary. So, we
        # have to find the desktop file to which it corresponds.
        desktop="`binary_to_desktop_file "$binary"`"
        basename "$desktop"
    fi
}

check_browser_gnome()
{
    check="`desktop_file_to_binary "$1"`"
    if [ -z "$check" ]; then
        echo no
        exit_success
    fi
    binary="`gconftool-2 --get /desktop/gnome/applications/browser/exec | first_word`"
    if [ x"$binary" != x"$check" ]; then
        echo no
        exit_success
    fi
    # Check HTTP and HTTPS, but not about: and unknown:.
    for protocol in http https; do
        binary="`gconftool-2 --get /desktop/gnome/url-handlers/$protocol/command | first_word`"
        if [ x"$binary" != x"$check" ]; then
            echo no
            exit_success
        fi
    done
    browser="`get_browser_mime`"
    binary="`desktop_file_to_binary "$browser"`"
    if [ x"$binary" != x"$check" ]; then
        echo no
        exit_success
    fi
    echo yes
    exit_success
}

set_browser_gnome()
{
    binary="`desktop_file_to_binary "$1"`"
    [ "$binary" ] || exit_failure_file_missing
    set_browser_mime "$1" || return

    # Set the default browser.
    gconftool-2 --type string --set /desktop/gnome/applications/browser/exec "$binary"
    gconftool-2 --type bool --set /desktop/gnome/applications/browser/needs_term false
    gconftool-2 --type bool --set /desktop/gnome/applications/browser/nremote true
    # Set the handler for HTTP and HTTPS.
    for protocol in http https; do
        gconftool-2 --type string --set /desktop/gnome/url-handlers/$protocol/command "$binary %s"
        gconftool-2 --type bool --set /desktop/gnome/url-handlers/$protocol/needs_terminal false
        gconftool-2 --type bool --set /desktop/gnome/url-handlers/$protocol/enabled true
    done
    # Set the handler for about: and unknown URL types.
    for protocol in about unknown; do
        gconftool-2 --type string --set /desktop/gnome/url-handlers/$protocol/command "$binary %s"
    done
}

# }}} GNOME
# {{{ GNOME 3.x

get_browser_gnome3()
{
    get_browser_mime "x-scheme-handler/http"
}

check_browser_gnome3()
{
    desktop="$1"
    check="`desktop_file_to_binary "$1"`"
    if [ -z "$check" ]; then
        echo no
        exit_success
    fi
    # Check HTTP and HTTPS, but not about: and unknown:.
    for protocol in http https; do
        browser="`get_browser_mime "x-scheme-handler/$protocol"`"
        if [ x"$browser" != x"$desktop" ]; then
            echo no
            exit_success
        fi
    done
    echo yes
    exit_success
}

set_browser_gnome3()
{
    binary="`desktop_file_to_binary "$1"`"
    [ "$binary" ] || exit_failure_file_missing
    set_browser_mime "$1" || return

    # Set the default browser.
    for protocol in http https about unknown; do
        set_browser_mime "$1" "x-scheme-handler/$protocol" || return
    done
}
# }}} GNOME 3.x
# {{{ LXQt

get_browser_lxqt()
{
    if qtxdg-mat def-web-browser --help 2> /dev/null 1>&2; then
        qtxdg-mat def-web-browser 2>/dev/null
    else
        exit_failure_operation_impossible "no method for getting the default browser"
    fi
}

check_browser_lxqt()
{
    desktop="$1"
    check="`desktop_file_to_binary "$1"`"
    if [ -z "$check" ]; then
        echo no
        exit_success
    fi

    if qtxdg-mat def-web-browser --help 2>/dev/null 1>&2; then
        browser="`qtxdg-mat def-web-browser`" 2>/dev/null
        if [ x"$browser" != x"$desktop" ]; then
            echo no
            exit_success
        fi
    else
        exit_failure_operation_impossible "no method for checking the default browser"
    fi
}

set_browser_lxqt()
{
    binary="`desktop_file_to_binary "$1"`"
    [ "$binary" ] || exit_failure_file_missing
    set_browser_mime "$1" || return

    # Set the default browser.
    for protocol in http https about unknown; do
        set_browser_mime "$1" "x-scheme-handler/$protocol" || return
    done
}
# }}} LXQt
# {{{ xfce

get_browser_xfce()
{
    search="${XDG_CONFIG_HOME:-$HOME/.config}:${XDG_CONFIG_DIRS:-/etc/xdg}"
    IFS=:
    for dir in $search; do
        unset IFS
        [ "$dir" ] && [ -d "$dir/xfce4" ] || continue
        file="$dir/xfce4/helpers.rc"
        [ -r "$file" ] || continue
        grep -q "^WebBrowser=" "$file" || continue
        desktop="`grep "^WebBrowser=" "$file" | cut -d= -f 2-`"
        echo "$desktop.desktop"
        return
    done
    exit_failure_operation_failed
}

check_browser_xfce()
{
    browser="`get_browser_xfce`"
    if [ x"$browser" != x"$1" ]; then
        echo no
        exit_success
    fi
    echo yes
    exit_success
}

check_xfce_desktop_file()
{
    # Annoyingly, xfce wants its .desktop files in a separate directory instead
    # of the standard locations, and requires a few custom tweaks to them:
    # "Type" must be "X-XFCE-Helper"
    # "X-XFCE-Category" must be "WebBrowser" (for web browsers, anyway)
    # "X-XFCE-Commands" and "X-XFCE-CommandsWithParameter" must be set
    search="${XDG_DATA_HOME:-$HOME/.local/share}:${XDG_DATA_DIRS:-/usr/local/share:/usr/share}"
    IFS=:
    for dir in $search; do
        unset IFS
        [ "$dir" ] && [ -d "$dir/xfce4/helpers" ] || continue
        file="$dir/xfce4/helpers/$1"
        # We have the file, no need to create it.
        [ -r "$file" ] && return
    done
    IFS=:
    for dir in $search; do
        unset IFS
        [ "$dir" ] && [ -d "$dir/applications" ] || continue
        file="$dir/applications/$1"
        if [ -r "$file" ]; then
            # Found a file to convert.
            target="${XDG_DATA_HOME:-$HOME/.local/share}/xfce4/helpers"
            mkdir -p "$target"
            # Copy file up to first "Exec=" line.
            sed -e 's/^Type=.*/Type=X-XFCE-Helper/' -e '/^Exec[=[]/,$d' "$file" > "$target/$1"
            echo "X-XFCE-Category=WebBrowser" >> "$target/$1"
            # Change %F, %f, %U, and %u to "%s".
            command=$(grep -E '^Exec(\[[^]=]*])?=' "$file" | cut -d= -f 2- | sed -e 's/%[FfUu]/"%s"/g' | head -1)
            echo "X-XFCE-Commands=`echo "$command" | first_word`" >> "$target/$1"
            echo "X-XFCE-CommandsWithParameter=$command" >> "$target/$1"
            # Copy rest of file (from first "Exec=" line to end-of-file).
            sed -n -e 's/^Type=.*/Type=X-XFCE-Helper/' -e '/^Exec[=[]/,$p' "$file" >> "$target/$1"
            return
        fi
    done
    return 1
}

set_browser_xfce()
{
    check_xfce_desktop_file "$1" || exit_failure_operation_failed

    helper_dir="${XDG_CONFIG_HOME:-$HOME/.config}/xfce4"
    if [ ! -d "$helper_dir" ]; then
        mkdir -p "$helper_dir" || exit_failure_operation_failed
    fi

    helpers_rc="$helper_dir/helpers.rc"
    # Create the file if it does not exist to avoid special cases below.
    if [ ! -r "$helpers_rc" ]; then
        touch "$helpers_rc" || exit_failure_operation_failed
    fi

    temp="`mktemp "$helpers_rc.XXXXXX"`" || return
    grep -v "^WebBrowser=" "$helpers_rc" >> "$temp"
    echo "WebBrowser=${1%.desktop}" >> "$temp"

    oldlines="`wc -l < "$helpers_rc"`"
    newlines="`wc -l < "$temp"`"
    # The new file should have at least as many lines as the old.
    if [ $oldlines -le $newlines ]; then
        mv "$temp" "$helpers_rc"
    else
        rm -f "$temp"
        return 1
    fi
}

# }}} xfce
# {{{ generic

get_browser_generic()
{
    if [ -n "$BROWSER" ]; then
        local browser=$(binary_to_desktop_file "${BROWSER%%:*}")
        if [ -n "$browser" ]; then
            basename "$browser"
            return 0
        fi
    fi

    if get_browser_mime x-scheme-handler/http; then
        return 0
    fi

    # Debian and derivatives have x-www-browser
    local browser=$(binary_to_desktop_file x-www-browser)
    if [ -n "$browser" ]; then
        basename "$browser"
        return 0
    fi

    return 4
}

check_browser_generic()
{
    local desktop="$1"

    # Check HTTP
    if [ "$desktop" != "$(get_browser_generic)" ]; then
        echo no
        exit_success
    fi

    # Check text/html
    if [ "$desktop" != "$(get_browser_mime)" ]; then
        echo no
        exit_success
    fi

    # Check HTTPS
    if [ "$desktop" != "$(get_url_scheme_handler_generic https)" ]; then
        echo no
        exit_success
    fi

    echo yes
    exit_success
}

set_browser_generic()
{
    if [ -n "$BROWSER" ]; then
        exit_failure_operation_failed \
            "\$BROWSER is set and can't be changed with xdg-settings"
    fi

    binary=$(desktop_file_to_binary "$1")
    [ -n "$binary" ] || exit_failure_file_missing

    set_browser_mime "$1" text/html || return

    for protocol in http https about unknown; do
        set_browser_mime "$1" "x-scheme-handler/$protocol" || return
    done
}
# }}} generic
# }}} default browser

# {{{ default url scheme handler

exit_unimplemented_default_handler()
{
    exit_failure_operation_impossible "default-url-scheme-handler not implemented for $DE"
}

# {{{ KDE

# Recent versions of KDE support default scheme handler applications using the
# mime type of x-scheme-handler/scheme. Older versions will not support this
# but do have support for setting a default mail handler. There is also a
# system in KDE where .protocol files can be used, however this is not
# supported by this script. When reading a scheme handler we will use the
# default mail handler for the mailto scheme, otherwise we will use the mime
# type x-scheme-handler/scheme.

get_url_scheme_handler_kde()
{
    if [ "$1" = "mailto" ]; then
        handler="`read_kde_config emaildefaults PROFILE_Default EmailClient | first_word`"
        echo "handler is $handler"
        if [ x"$handler" != x ]; then
            binary_to_desktop_file "$handler"
        else
            get_browser_mime "x-scheme-handler/$1"
        fi
    else 
        get_browser_mime "x-scheme-handler/$1"
    fi
}

check_url_scheme_handler_kde()
{
    check="`desktop_file_to_binary "$2"`"
    if [ -z "$check" ]; then
        echo no
        exit_success
    fi
    if [ "$1" = "mailto" ]; then
        binary="`read_kde_config emaildefaults PROFILE_Default EmailClient`"
        # The field may contain a relative entry to the binary starting with !
        case "$browser" in !*)
            # get the full path
            desktop_file="`binary_to_desktop_file ${binary#!}`"
            binary="`desktop_file_to_binary $desktop_file`"
        esac
        if [ x"$binary" != x"$check" ]; then
            echo no
            exit_success
        fi
    else
        handler="`get_browser_mime x-scheme-handler/$1`"
        binary="`desktop_file_to_binary "$handler"`"
        if [ x"$binary" != x"$check" ]; then
            echo no
            exit_success
        fi
    fi
    echo yes
    exit_success
}

set_url_scheme_handler_kde()
{
    set_browser_mime "$2" "x-scheme-handler/$1" || return
    if [ "$1" = "mailto" ]; then
        binary="`desktop_file_to_binary "$2"`"
        if [ x"${KDE_SESSION_VERSION}" = x"5" ]; then
            kwriteconfig5 --file emaildefaults --group PROFILE_Default --key EmailClient "$binary"
        elif [ x"${KDE_SESSION_VERSION}" = x"6" ]; then
            kwriteconfig6 --file emaildefaults --group PROFILE_Default --key EmailClient "$binary"
        else
            kwriteconfig --file emaildefaults --group PROFILE_Default --key EmailClient "$binary"
        fi
    fi
}

# }}} KDE
# {{{ GNOME

get_url_scheme_handler_gnome()
{
    binary="`gconftool-2 --get /desktop/gnome/url-handlers/$1/command | first_word`"
    if [ x"$binary" != x"" ]; then
        # gconftool gives the binary (maybe with %s etc. afterward),
        # but we want the desktop file name, not the binary. So, we
        # have to find the desktop file to which it corresponds.
        desktop="`binary_to_desktop_file "$binary"`"
        basename "$desktop"
    fi
}

check_url_scheme_handler_gnome()
{
    check="`desktop_file_to_binary "$2"`"
    if [ -z "$check" ]; then
        echo no
        exit_success
    fi
    binary="`gconftool-2 --get /desktop/gnome/url-handlers/$1/command | first_word`"
    if [ x"$binary" != x"$check" ]; then
        echo no
        exit_success
    fi
    echo yes
    exit_success
}

set_url_scheme_handler_gnome()
{
    binary="`desktop_file_to_binary "$2"`"
    [ "$binary" ] || exit_failure_file_missing

    gconftool-2 --type string --set /desktop/gnome/url-handlers/$1/command "$binary %s"
    gconftool-2 --type bool --set /desktop/gnome/url-handlers/$1/needs_terminal false
    gconftool-2 --type bool --set /desktop/gnome/url-handlers/$1/enabled true
}

# }}} GNOME
# {{{ LXQt

get_url_scheme_handler_lxqt()
{
    if qtxdg-mat defapp --help 2> /dev/null 1>&2; then
        qtxdg-mat defapp "x-scheme-handler/$1" 2> /dev/null
    else
        exit_failure_operation_impossible "no method for getting the url_scheme_handler"
    fi
}

check_url_scheme_handler_lxqt()
{
    desktop="$2"
    check="`desktop_file_to_binary "$2"`"
    if [ -z "$check" ]; then
        echo no
        exit_success
    fi

    if qtxdg-mat defapp --help 2> /dev/null 1>&2; then
        handler="`qtxdg-mat defapp "x-scheme-handler/$1"`" 2> /dev/null
        if [ x"$handler" != x"$desktop" ]; then
            echo no
            exit_success
        fi
    else
        exit_failure_operation_impossible "no method for checking the url_scheme_handler for desktop $DE"
    fi
}

set_url_scheme_handler_lxqt()
{
    binary="`desktop_file_to_binary "$2"`"
    [ "$binary" ] || exit_failure_file_missing
    set_browser_mime "$2" || return

    # Set the default browser.
    set_browser_mime "$2" "x-scheme-handler/$1" || return
}

# }}} LXQt
# {{{ GNOME 3.x

get_url_scheme_handler_gnome3()
{
    get_browser_mime "x-scheme-handler/$1"
}

check_url_scheme_handler_gnome3()
{
    desktop="$2"
    check="`desktop_file_to_binary "$2"`"
    if [ -z "$check" ]; then
        echo no
        exit_success
    fi
    browser="`get_browser_mime "x-scheme-handler/$1"`"
    if [ x"$browser" != x"$desktop" ]; then
        echo no
        exit_success
    fi
    echo yes
    exit_success
}

set_url_scheme_handler_gnome3()
{
    binary="`desktop_file_to_binary "$2"`"
    [ "$binary" ] || exit_failure_file_missing

    # Set the default browser.
    set_browser_mime "$2" "x-scheme-handler/$1" || return
}

# }}} GNOME 3.x
# {{{ xfce

get_url_scheme_handler_xfce()
{
    exit_unimplemented_default_handler "$1"
}

check_url_scheme_handler_xfce()
{
    exit_unimplemented_default_handler "$1"
}

set_url_scheme_handler_xfce()
{
    exit_unimplemented_default_handler "$1"
}

# }}} xfce
# {{{ generic

get_url_scheme_handler_generic()
{
    if [ -n "$BROWSER" ] && ([ "$1" = http ] || [ "$1" = https ]); then
        get_browser_generic
    else
        get_browser_mime "x-scheme-handler/$1"
    fi
}

check_url_scheme_handler_generic()
{
    local scheme="$1" desktop="$2"

    if [ -z "$(desktop_file_to_binary "$desktop")" ]; then
        echo no
        exit_success
    fi

    local browser=$(get_url_scheme_handler_generic "$scheme")
    if [ "$browser" != "$desktop" ]; then
        echo no
        exit_success
    fi
    echo yes
    exit_success
}

set_url_scheme_handler_generic()
{
    local scheme="$1" desktop="$2"

    if [ -n "$BROWSER" ] && \
           ([ "$scheme" = http ] || [ "$scheme" = https ]); then
        exit_failure_operation_failed \
            "\$BROWSER is set and can't be changed with xdg-settings"
    fi

    if [ -z "$(desktop_file_to_binary "$desktop")" ]; then
        exit_failure_file_missing
    fi

    set_browser_mime "$desktop" "x-scheme-handler/$scheme"
}

# }}} generic
# }}} default protocol handler

dispatch_specific()
{
    local handler=$1; shift
    # The PROP comments in this function are used to generate the output of
    # the --list option. The formatting is important. Make sure to line up the
    # property descriptions with spaces so that it will look nice.
    if [ x"$op" = x"get" ]; then
        case "$parm" in
          default-web-browser) # PROP:           Default web browser
            get_browser_$handler
            ;;

          default-url-scheme-handler) # PROP:    Default handler for URL scheme
            get_url_scheme_handler_$handler "$1"
            ;;

          *)
            exit_failure_syntax
            ;;
        esac
    elif [ x"$op" = x"check" ]; then
        case "$parm" in
          default-web-browser)
            check_desktop_filename "$1"
            check_browser_$handler "$1"
            ;;

          default-url-scheme-handler)
            check_desktop_filename "$2"
            check_url_scheme_handler_$handler "$1" "$2"
            ;;

          *)
            exit_failure_syntax
            ;;
        esac
    else # set
        case "$parm" in
          default-web-browser)
	    [ $# -eq 1 ] || exit_failure_syntax "unexpected/missing argument"
            check_desktop_filename "$1"
            set_browser_$handler "$1"
            ;;

          default-url-scheme-handler)
	    [ $# -eq 2 ] || exit_failure_syntax "unexpected/missing argument"
            check_desktop_filename "$2"
            set_url_scheme_handler_$handler "$1" "$2"
            ;;

          *)
            exit_failure_syntax
            ;;
        esac
    fi

    if [ $? -eq 0 ]; then
        exit_success
    else
        exit_failure_operation_failed
    fi
}

if [ x"$1" = x"--list" ]; then
    echo "Known properties:"
    # Extract the property names from dispatch_specific() above.
    grep "^[ 	]*[^)]*) # PROP:" "$0" | sed -e 's/^[ 	]*\([^)]*\)) # PROP: \(.*\)$/  \1 \2/' | sort
    exit_success
fi

[ x"$1" != x ] || exit_failure_syntax "no operation given"
[ x"$2" != x ] || exit_failure_syntax "no parameter name given"
[ x"$1" = x"get" ] || [ x"$3" != x ] || exit_failure_syntax "no parameter value given"

op="$1"
parm="$2"
shift 2

if [ x"$op" != x"get" ] && [ x"$op" != x"check" ] && [ x"$op" != x"set" ]; then
  exit_failure_syntax "invalid operation"
fi

detectDE

if [ -z "$DE" ]; then
    DE=generic
fi

case "$DE" in
    kde)
    dispatch_specific kde "$@"
    ;;

    deepin)
    dispatch_specific deepin "$@"
    ;;

    gnome)
    dispatch_specific gnome "$@"
    ;;

    gnome3|cinnamon|lxde|mate)
    dispatch_specific gnome3 "$@"
    ;;

    lxqt)
    dispatch_specific lxqt "$@"
    ;;

    xfce)
    dispatch_specific xfce "$@"
    ;;

    generic|enlightenment)
    dispatch_specific generic "$@"
    ;;

    *)
    exit_failure_operation_impossible "unknown desktop environment"
    ;;
esac