#!/bin/bash

set -e

DIR="$(dirname "$0")"
VERSION="$(cat $DIR/VERSION | tr -d '[:space:]')"

# target executable
SOURCE="$DIR/comfortable-swipe"
TARGET="/usr/local/bin/comfortable-swipe"

# compile targets
COMPILE="$DIR/compile"
COMPILE_SOURCE="$DIR/comfortable-swipe-main.cpp"
COMPILE_TARGET="/usr/local/bin/comfortable-swipe-buffer"

# configurations
CONF_SOURCE="$DIR/config/comfortable-swipe.conf"
CONF_TARGET="$HOME/.config/comfortable-swipe.conf"
OLD_CONF_TARGET="/usr/local/share/comfortable-swipe/comfortable-swipe.conf"

# autostart
AUTOSTART_SOURCE="$DIR/config/comfortable-swipe.desktop"
AUTOSTART_TARGET="$HOME/.config/autostart/comfortable-swipe.desktop"

# stop any running comfortable-swipe if it exists
comfortable-swipe stop > /dev/null 2>&1 || true


# shorthand to abort the installation
function abort {
    echo "Installation aborted"
    exit 1
}

# shorthand to try a command with sudo if it fails
function trysudo {
    $@ 2> /dev/null || sudo $@
}

# uninstall existing program
function uninstall_existing {
    local PROGRAM="${1:?missing program name}"
    # remove existing comfortable-swipe
    if [[ -x "$(command -v "$PROGRAM")" ]]; then
        echo -n "Removing previous $(which "$PROGRAM") ... "
        trysudo rm -f "$(which "$PROGRAM")"
        echo "ok"
    fi
}


## CONFIGURATION FILE LOADING
# This section handles installation of configuration file.
# We determine first if any old configuration files exists.
# make sure config directory exists
function install_configuration_file {
    mkdir -p "$(dirname "$CONF_TARGET")"

    # check if configuration already exists
    if [[ -f "$CONF_TARGET" ]]; then
        # ask user if we overwrite configuration
        echo "Old conf file found in $CONF_TARGET" >&2
        read -r -p "Keep the old conf file? (default: yes) [Y/n] " response >&2
        if ! [[ "${response,,}" =~ ^(yes|y)$ ]]; then
            # MAKE SURE they really want to overwrite
            read -r -p "Conf file will be overwritten! Are you sure? [Y/n] " response >&2
            if [[ "${response,,}" =~ ^(yes|y)$ ]]; then
                # They agreed... replace configuration
                cat "$CONF_SOURCE" > "$CONF_TARGET"
            else
                abort
            fi
        fi
    else
        # target does not exist yet
        # try copying from older configurations
        if [[ -f "$OLD_CONF_TARGET" ]]; then
            # move configuration from an older version (< v1.2)
            echo "Moving configuration from $OLD_CONF_TARGET to $CONF_TARGET ..."
            mv "$OLD_CONF_TARGET" "$CONF_TARGET"
            # clean up old directory if possible
            rmdir "$(dirname "$OLD_CONF_TARGET")" > /dev/null 2>&1 || true
        else
            # fresh installation! just copy default configuration
            cat "$CONF_SOURCE" > "$CONF_TARGET"
        fi
    fi

    echo "Installed: $CONF_TARGET"
}


## Installation of main program
#
#    /usr/local/bin/comfortable-swipe
#
function install_main_program {
    # copy source to target with executable permissions
    TRYSUDO=
    if ! touch "$TARGET" 2> /dev/null; then
        TRYSUDO=sudo
    fi
    # install to target, with hardcoded version
    $TRYSUDO sed -E "s/^VERSION=.*/VERSION=$VERSION/" "$SOURCE" > "$TARGET"
    # allow execute permissions
    $TRYSUDO chmod +x "$TARGET"
    echo "Installed: $TARGET"
}



## Compilation and installation of C++ buffer program:
#
#    /usr/local/bin/comfortable-swipe-buffer
#
function install_cpp_program {
    # compile program to temporary file first
    TMP_TARGET="$(mktemp)"
    $COMPILE "$COMPILE_SOURCE" -o "$TMP_TARGET" -DCOMFORTABLE_SWIPE_VERSION="\"$VERSION\"" -DCOMFORTABLE_SWIPE_CONFIG="\"$CONF_TARGET\"" -DCOMFORTABLE_SWIPE_AUTOSTART="\"$AUTOSTART_TARGET\""
    # compilation ok, now try to install
    # eheck permissions maybe if will need sudo
    TRYSUDO=
    if ! touch "$COMPILE_TARGET" 2> /dev/null; then
        TRYSUDO=sudo
    fi
    # move executable to target
    $TRYSUDO mv "$TMP_TARGET" "$COMPILE_TARGET"
    echo "Installed: $COMPILE_TARGET"
}



## Installation of Autostart Desktop file
#
#     /home/$USER/.config/autostart/comfortable-swipe.desktop
#
function install_autostart {
    cat "$AUTOSTART_SOURCE" > "$AUTOSTART_TARGET"
    echo "Installed: $AUTOSTART_TARGET"
}


# install configuration files first but defer output later
# this is to ensure that the prompt runs first in the script
INSTALL_CONF_OUTPUT="$(install_configuration_file)"

# uninstall existing commands
uninstall_existing comfortable-swipe
uninstall_existing comfortable-swipe-buffer

# install new binaries
echo "Installing binaries ..."
install_cpp_program
install_main_program
echo "$INSTALL_CONF_OUTPUT"
install_autostart

# add permissions to input group (defer)
# GROUP=$(ls -l /dev/input/event* | awk '{print $4}' | head --line=1) || abort

# make sure comfortable-swipe is in path
if ! command -v comfortable-swipe > /dev/null 2>&1; then
cat <<EOF >&2
WARNING: $(dirname "$TARGET") is not in PATH!
Make sure to add the following in your ~/.profile:

    export PATH="$PATH:$(dirname "$TARGET")"

EOF
fi

cat <<EOF

Successfully installed comfortable-swipe $VERSION
Autostart switched $("$TARGET" autostart status)

EOF

# start the program
"$TARGET" start