#!/bin/bash

# swp-install by Mason Nelson
# ===============================================================================
# Script to install SkywarnPlus. This script will determine the system type (ASL1/2, ASL3, or HamVoIP),
# install the required dependencies, download the latest version of SkywarnPlus from GitHub,
# configure the necessary permissions, and set up a crontab entry to run SkywarnPlus at a specified interval.
# This script also checks if the SkywarnPlus directory already exists and asks for user confirmation to remove it before continuing.
# Please note that this script should be run as root.

# This file is part of SkywarnPlus.
# SkywarnPlus is free software: you can redistribute it and/or modify it under the terms of
# the GNU General Public License as published by the Free Software Foundation, either version 3
# of the License, or (at your option) any later version. SkywarnPlus 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 General Public License for more details.
# You should have received a copy of the GNU General Public License along with SkywarnPlus. If not, see <https://www.gnu.org/licenses/>.

clear

print_divider() {
    echo "========================================"
}

print_notice() {
    print_divider
    echo "This script is designed to automate the installation of SkywarnPlus."
    echo "Author: Mason Nelson"
    echo
    echo
    echo "NOTE: This script is an installer only and will NOT automate configuration."
    echo "Please edit the config.yaml file manually after installation."
    print_divider
    read -r -p "Would you like to continue? (y/n) [y]: " CONTINUE
    CONTINUE=${CONTINUE:-y}
    if [[ "$CONTINUE" != [Yy] ]]; then
        print_divider
        echo "Installation aborted. Exiting."
        print_divider
        exit 1
    fi
}

check_root() {
    if [ "$EUID" -ne 0 ]; then
        print_divider
        echo "This script must be run as root. Exiting."
        print_divider
        exit 1
    fi
}

determine_system_type() {
    echo "Determining system type..."
    if [ -f /etc/debian_version ]; then
        . /etc/os-release
        OS=$ID
        VER=$VERSION_ID
        ASTERISK_VERSION=$(asterisk -V)
        if [[ "$ASTERISK_VERSION" =~ "Asterisk "([2-9][0-9]|[1-9][0-9]{2,}) ]]; then
            SYSTEM_TYPE="ASL3"
        else
            SYSTEM_TYPE="ASL1/2"
        fi
    elif [ -f /etc/arch-release ]; then
        OS=arch
        VER=$(uname -r)
        SYSTEM_TYPE="HamVoIP"
    else
        print_divider
        echo "Unsupported OS. This script supports only Debian and Arch."
        print_divider
        exit 1
    fi
}

confirm_system_type() {
    print_divider
    echo "Detected system type: $SYSTEM_TYPE."
    print_divider
    read -r -p "Is this correct? Enter 'y' for yes or 'n' for no to override. [y]: " CONFIRMATION
    CONFIRMATION=${CONFIRMATION:-y}
    if [[ "$CONFIRMATION" != [Yy] ]]; then
        print_divider
        echo "Please enter the correct system type:"
        echo "1 = ASL1/2"
        echo "3 = ASL3"
        echo "5 = HamVoIP"
        print_divider
        read -r -p "Enter the system type number: " SYSTEM_TYPE_INPUT
        SYSTEM_TYPE_INPUT=${SYSTEM_TYPE_INPUT:-3}
        case $SYSTEM_TYPE_INPUT in
            1)
                SYSTEM_TYPE="ASL1/2"
                ;;
            3)
                SYSTEM_TYPE="ASL3"
                ;;
            5)
                SYSTEM_TYPE="HamVoIP"
                ;;
            *)
                print_divider
                echo "Invalid input. Exiting."
                print_divider
                exit 1
                ;;
        esac
    fi
}

install_dependencies() {
    print_divider
    echo "Installing dependencies..."
    if [ "$OS" = "debian" ]; then
        apt update
        if [ "$SYSTEM_TYPE" = "ASL1/2" ]; then
            apt install -y unzip python3 python3-pip ffmpeg
            pip3 install ruamel.yaml requests python-dateutil pydub
        else
            apt install -y unzip python3 python3-pip ffmpeg python3-ruamel.yaml python3-requests python3-dateutil python3-pydub
        fi
    elif [ "$OS" = "arch" ]; then
        pacman -Syu --noconfirm
        pacman -S --noconfirm --needed ffmpeg
        if ! command -v pip &> /dev/null; then
            wget -q https://bootstrap.pypa.io/pip/3.5/get-pip.py
            python get-pip.py
        fi
        pip install requests python-dateutil pydub ruamel.yaml==0.15.100
    else
        print_divider
        echo "Unsupported OS version. Exiting."
        print_divider
        exit 1
    fi
}

check_existing() {
    if [ -d "/usr/local/bin/SkywarnPlus" ]; then
        print_divider
        echo "Existing SkywarnPlus installation detected. This installer script was intended for new installations."
        read -r -p "Would you like to run UpdateSWP.py instead?

[Y] Switch to UpdateSWP.py
[N] Continue with a fresh install after making a backup to SkywarnPlus_$(date +'%m-%d-%Y')/
    (you can grab your old config.yaml file from the backup)

Please choose an option (y/n) [y]: " INSTALL_OPTION
        INSTALL_OPTION=${INSTALL_OPTION:-y}
        
        if [[ "$INSTALL_OPTION" =~ ^[Yy]$ ]]; then
            print_divider
            echo "Switching to UpdateSWP.py..."
            print_divider
            /usr/local/bin/SkywarnPlus/UpdateSWP.py
            exit 0
        else
            BACKUP_DIR="/usr/local/bin/SkywarnPlus_$(date +'%m-%d-%Y')"
            print_divider
            echo "Making a backup to $BACKUP_DIR..."
            mv /usr/local/bin/SkywarnPlus "$BACKUP_DIR"
            print_divider
            echo "Backup complete. Continuing with fresh installation..."
        fi
    fi
}

download_swp() {
    print_divider
    echo "Downloading SkywarnPlus..."
    wget -q -P /usr/local/bin https://github.com/Mason10198/SkywarnPlus/releases/latest/download/SkywarnPlus.zip
    unzip /usr/local/bin/SkywarnPlus.zip -d /usr/local/bin
    rm /usr/local/bin/SkywarnPlus.zip
}

configure_perms() {
    print_divider
    echo "Configuring permissions..."

    if [ "$SYSTEM_TYPE" = "ASL3" ]; then
        chown -R asterisk:asterisk /usr/local/bin/SkywarnPlus/
        chmod -R u+rw /usr/local/bin/SkywarnPlus/
    fi

    chmod +x /usr/local/bin/SkywarnPlus/*.py
}

remove_old_cron() {
    print_divider
    echo "Checking for "old style" crontab entry for SkywarnPlus.py..."
    CRONTAB_OLD=$(crontab -l | grep 'SkywarnPlus.py')
    if [ -n "$CRONTAB_OLD" ]; then
        echo "Found "old style" crontab entry for SkywarnPlus.py:"
        echo "$CRONTAB_OLD"
        echo "This must be removed to avoid conflicts. A new crontab entry will reside in /etc/cron.d/SkywarnPlus."
        echo "Removing "old style" crontab entry for SkywarnPlus.py..."
        (crontab -l | grep -v 'SkywarnPlus.py') | crontab -
        echo ""Old style" crontab entry for SkywarnPlus.py removed."
    else
        echo "No "old style" crontab entry found for SkywarnPlus.py."
    fi

    print_divider
    echo "Checking for existing crontab entry for ast_var_update.sh..."
    CRONTAB_AST=$(crontab -l | grep 'ast_var_update.sh')
    if [ -n "$CRONTAB_AST" ]; then
        echo "It looks like you have added a crontab entry for ast_var_update.sh - this functionality will now be handled by SkywarnPlus, and this crontab entry should be removed to avoid conflicts."
        read -r -p "Would you like to remove the crontab entry now? (y/n) [y]: " choice
        choice=${choice:-y}
        if [[ "$choice" =~ ^[Yy]$ ]]; then
            echo "Removing old crontab entry for ast_var_update.sh..."
            (crontab -l | grep -v 'ast_var_update.sh') | crontab -
            echo "Old crontab entry for ast_var_update.sh removed."
        else
            echo "Crontab entry for ast_var_update.sh not removed."
        fi
    else
        echo "No existing crontab entry found for ast_var_update.sh."
    fi
}

setup_crontab() {
    print_divider
    CRON_FILE="/etc/cron.d/SkywarnPlus"
    
    if [ -f "$CRON_FILE" ]; then
        EXISTING_INTERVAL=$(grep -o '^\*/[0-9]*' "$CRON_FILE" | cut -d'/' -f2)
        if [ -n "$EXISTING_INTERVAL" ]; then
            echo "An existing crontab entry for SkywarnPlus was found with a $EXISTING_INTERVAL minute interval."
            echo
            echo "By default, the existing crontab entry will be kept."
            echo
            echo "To keep the existing interval, press enter."
            echo "To change the interval, enter a different number of minutes."
            echo "To disable the crontab entry and require manual execution, enter '0'."
            read -r -p "Keep existing interval [$EXISTING_INTERVAL]: " CRONTAB_INTERVAL
            print_divider
            CRONTAB_INTERVAL=${CRONTAB_INTERVAL:-$EXISTING_INTERVAL}
        fi
    else
        echo "By default, a new crontab entry will be added to trigger SkywarnPlus (check for alerts) every 1 minute."
        echo
        echo "If you would like to increase this interval, enter a different number of minutes."
        echo "To disable the crontab entry and require manual execution, enter '0'."
        read -r -p "To keep the default 1 minute interval, press enter. [1]: " CRONTAB_INTERVAL
        print_divider
        CRONTAB_INTERVAL=${CRONTAB_INTERVAL:-1}
    fi

    if [ "$CRONTAB_INTERVAL" -eq 0 ]; then
        if [ -f "$CRON_FILE" ]; then
            rm "$CRON_FILE"
            echo "Existing crontab entry removed. You will need to run SkywarnPlus manually."
        else
            echo "No crontab entry created. You will need to run SkywarnPlus manually."
        fi
    else
        if [ "$SYSTEM_TYPE" = "ASL3" ]; then
            CRONTAB_ENTRY="*/$CRONTAB_INTERVAL * * * * asterisk /usr/local/bin/SkywarnPlus/SkywarnPlus.py"
        else
            CRONTAB_ENTRY="*/$CRONTAB_INTERVAL * * * * root /usr/local/bin/SkywarnPlus/SkywarnPlus.py"
        fi

        if grep -Fxq "$CRONTAB_ENTRY" "$CRON_FILE" 2>/dev/null; then
            echo "Crontab entry already exists. Skipping."
        else
            echo "$CRONTAB_ENTRY" > "$CRON_FILE" || {
                print_divider
                echo "Failed to create crontab entry. Exiting."
                print_divider
                exit 1
            }
        fi
    fi
}

edit_config() {
    print_divider
    echo "Installation and configuration complete. Please edit the config.yaml file as per your needs."
    print_divider
    read -r -p "Would you like to edit the config.yaml file now? (y/n) [y]: " EDIT_CONFIG
    EDIT_CONFIG=${EDIT_CONFIG:-y}
    if [[ "$EDIT_CONFIG" =~ ^[Yy]$ ]]; then
        nano /usr/local/bin/SkywarnPlus/config.yaml
    else
        echo "You can edit the config.yaml file later using your preferred text editor."
    fi
}

main() {
    check_root
    print_notice
    determine_system_type
    confirm_system_type
    install_dependencies
    check_existing
    download_swp
    configure_perms
    remove_old_cron
    setup_crontab
    edit_config
}

main