#!/bin/bash
set -euo pipefail

##########################
# Color helpers (no tput)
##########################
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'
CYAN='\033[0;36m'
GRAY='\033[0;37m'
BOLD='\033[1m'
RESET='\033[0m'

# Disable colors if output is not a terminal
if [ ! -t 1 ]; then
    RED='' GREEN='' YELLOW='' CYAN='' GRAY='' BOLD='' RESET=''
fi

color_red()    { printf '%b' "$RED"; }
color_green()  { printf '%b' "$GREEN"; }
color_yellow() { printf '%b' "$YELLOW"; }
color_cyan()   { printf '%b' "$CYAN"; }
color_gray()   { printf '%b' "$GRAY"; }
color_reset()  { printf '%b' "$RESET"; }

##########################
# Use exported variables from main detection script
##########################
OS="${DETECTED_OS}"
DDE="${DETECTED_DE}"
DE="${SELECTED_DE:-none}"
TWM="${SELECTED_TWM:-none}"
INSTALL_LEVEL="${INSTALL_LEVEL:-minimal}"
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

echo
echo "${CYAN}Starting Debian setup...${RESET}"
echo
echo "DE: $DE, TWM: $TWM, Install Level: $INSTALL_LEVEL"



##########################
# 0. Ensure curl is installed
##########################
if ! command -v curl >/dev/null 2>&1; then
    echo
    echo "${YELLOW}curl is not installed. Installing...${RESET}"
    sudo apt update
    sudo apt -y install curl
fi

##########################
# 1. Add contrib and non-free if missing
##########################
echo
echo "${YELLOW}Checking /etc/apt/sources.list for contrib/non-free...${RESET}"
sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak.$(date +%s)
sudo sed -i -r 's/^(deb\s+\S+\s+\S+)\s+(main)$/\1 main contrib non-free/' /etc/apt/sources.list
echo
echo "${GREEN}Updated sources.list to include contrib/non-free where needed.${RESET}"

##########################
# 1a. Update archive.debian.org if needed
##########################
CURRENT_CODENAME=$(grep -Po 'deb\s+\S+\s+\K\S+' /etc/apt/sources.list | grep -E '^(buster|bullseye|bookworm|trixie)$' | head -n1)
DEBIAN_ORDER=(buster bullseye bookworm trixie)

codename_index() {
    local code="$1"
    for i in "${!DEBIAN_ORDER[@]}"; do
        [[ "${DEBIAN_ORDER[$i]}" == "$code" ]] && echo "$i" && return
    done
    echo -1
}

CURRENT_INDEX=$(codename_index "$CURRENT_CODENAME")
BULLSEYE_INDEX=$(codename_index "bullseye")

if [[ "$CURRENT_INDEX" -ge "$BULLSEYE_INDEX" ]] && grep -q "archive.debian.org" /etc/apt/sources.list; then
    echo
    echo "${YELLOW}Found archive.debian.org in sources.list and system is Bullseye or newer, updating to deb.debian.org...${RESET}"
    sudo sed -i -r 's|archive\.debian\.org|deb.debian.org|g' /etc/apt/sources.list
    echo
    echo "${GREEN}Updated sources.list to use deb.debian.org.${RESET}"
fi

##########################
# 2. Full update and upgrade
##########################
echo
echo "${YELLOW}Updating package lists...${RESET}"
sudo apt update

# Autoremove before full-upgrade
AUTOREMOVE_PENDING=$(apt -s autoremove | grep -E 'Remv' || true)
if [[ -n "$AUTOREMOVE_PENDING" ]]; then
    echo
    echo "${YELLOW}Removing packages that are no longer required before upgrade...${RESET}"
    sudo apt -y autoremove
fi

echo
echo "${YELLOW}Upgrading installed packages...${RESET}"
sudo apt -y full-upgrade

# Autoremove after full-upgrade
AUTOREMOVE_PENDING=$(apt -s autoremove | grep -E 'Remv' || true)
if [[ -n "$AUTOREMOVE_PENDING" ]]; then
    echo
    echo "${YELLOW}Removing packages that are no longer required after upgrade...${RESET}"
    sudo apt -y autoremove
fi

UPGRADE_PENDING=$(apt list --upgradable 2>/dev/null | grep -v Listing || true)
if [[ -n "$UPGRADE_PENDING" ]]; then
    echo
    echo "${RED}Some packages were upgraded. A reboot is recommended before continuing.${RESET}"
    read -rp "Reboot now? [y/N]: " reboot_choice
    case "${reboot_choice,,}" in
        y|yes)
            echo
            echo "${RED}Rebooting now. After reboot, please restart this script to continue...${RESET}"
            sudo reboot
            ;;
        *)
            echo
            echo "${YELLOW}Skipping reboot. Make sure to reboot manually before continuing upgrades.${RESET}"
            exit 0
            ;;
    esac
else
    echo
    echo "${GREEN}All packages are up to date. Continuing to Debian major version check...${RESET}"
fi

##########################
# 3. Stepwise major version upgrade
##########################
DEBIAN_SEQUENCE=(buster bullseye bookworm trixie)
CURRENT_CODENAME=$(grep -Po 'deb\s+\S+\s+\K\S+' /etc/apt/sources.list | grep -E '^(buster|bullseye|bookworm|trixie)$' | head -n1)
LATEST_CODENAME=${DEBIAN_SEQUENCE[-1]}

echo
echo "${CYAN}Current codename: $CURRENT_CODENAME"
echo "Latest stable codename: $LATEST_CODENAME${RESET}"

while [[ "$CURRENT_CODENAME" != "$LATEST_CODENAME" ]]; do
    NEXT_CODENAME=""
    for i in "${!DEBIAN_SEQUENCE[@]}"; do
        if [[ "${DEBIAN_SEQUENCE[$i]}" == "$CURRENT_CODENAME" ]]; then
            NEXT_CODENAME="${DEBIAN_SEQUENCE[$((i+1))]}"
            break
        fi
    done

    if [[ -z "$NEXT_CODENAME" ]]; then
        echo
        echo "${RED}Error: Cannot determine next codename after $CURRENT_CODENAME${RESET}"
        exit 1
    fi

    echo
    echo "${YELLOW}Detected codename $CURRENT_CODENAME, next stable version: $NEXT_CODENAME${RESET}"
    read -rp "Do you want to upgrade to $NEXT_CODENAME? [y/N]: " choice
    case "${choice,,}" in
        y|yes)
            echo
            echo "${YELLOW}Updating sources.list to $NEXT_CODENAME...${RESET}"
            sudo sed -i -r "s/\b$CURRENT_CODENAME\b/$NEXT_CODENAME/g" /etc/apt/sources.list

            echo
            echo "${YELLOW}Updating packages...${RESET}"
            sudo apt update

            AUTOREMOVE_PENDING=$(apt -s autoremove | grep -E 'Remv' || true)
            if [[ -n "$AUTOREMOVE_PENDING" ]]; then
                echo
                echo "${YELLOW}Removing packages that are no longer required before upgrade...${RESET}"
                sudo apt -y autoremove
            fi

            sudo apt -y full-upgrade

            AUTOREMOVE_PENDING=$(apt -s autoremove | grep -E 'Remv' || true)
            if [[ -n "$AUTOREMOVE_PENDING" ]]; then
                echo
                echo "${YELLOW}Removing packages that are no longer required after upgrade...${RESET}"
                sudo apt -y autoremove
            fi

            echo
            echo "${GREEN}Upgrade to $NEXT_CODENAME complete. A reboot is recommended.${RESET}"
            read -rp "Press Enter to reboot..." _
            sudo reboot
            ;;
        *)
            echo
            echo "${YELLOW}Skipping upgrade to $NEXT_CODENAME. Continuing with current version.${RESET}"
            break
            ;;
    esac

    CURRENT_CODENAME=$(grep -Po 'deb\s+\S+\s+\K\S+' /etc/apt/sources.list | grep -E '^(buster|bullseye|bookworm|trixie)$' | head -n1)
done

echo
echo "${GREEN}Debian is now at codename $CURRENT_CODENAME. Continuing with DE/TWM installation...${RESET}"

##########################
# 4. Desktop Environment installation
##########################
case "$DE" in
    xfce|plasma|gnome)
        echo
        echo "${YELLOW}Preparing to install $DE...${RESET}"

        SCRIPT_NAME="$SCRIPT_DIR/${OS}-${DE}.sh"
        if [[ -f "$SCRIPT_NAME" ]]; then
            echo
            echo "${CYAN}Running $SCRIPT_NAME...${RESET}"
            bash "$SCRIPT_NAME"
        else
            echo
            echo "${RED}Error: $SCRIPT_NAME not found!${RESET}"
            exit 1
        fi
        ;;
    none)
        echo
        echo "${GRAY}No Desktop Environment selected, skipping DE installation.${RESET}"
        ;;
esac

##########################
# 5. Tiling Window Manager installation
##########################
case "$TWM" in
    chadwm|hyprland)
        echo
        echo "${YELLOW}Installing $TWM...${RESET}"

        SCRIPT_NAME="$SCRIPT_DIR/${OS}-${TWM}.sh"
        if [[ -f "$SCRIPT_NAME" ]]; then
            echo
            echo "${CYAN}Running $SCRIPT_NAME...${RESET}"
            bash "$SCRIPT_NAME"
        else
            echo
            echo "${RED}Error: $SCRIPT_NAME not found!${RESET}"
            exit 1
        fi
        ;;
    none)
        echo
        echo "${GRAY}No tiling window manager selected.${RESET}"
        ;;
esac

##########################
# 6. Installation level handling
##########################
case "$INSTALL_LEVEL" in
    minimal|full|workstation|server)
        echo
        echo "${CYAN}Installation level: $INSTALL_LEVEL${RESET}"

        SCRIPT_NAME="$SCRIPT_DIR/${OS}-${INSTALL_LEVEL}.sh"
        if [[ -f "$SCRIPT_NAME" ]]; then
            echo
            echo "${CYAN}Running $SCRIPT_NAME...${RESET}"
            bash "$SCRIPT_NAME"
        else
            echo
            echo "${RED}Error: $SCRIPT_NAME not found!${RESET}"
            exit 1
        fi
        ;;
esac

echo
echo "${GREEN}Debian setup complete.${RESET}"

##########################
# 7. Installation Finished
##########################
    echo
    echo "${RED}The installation has finished. A reboot is recommended before continuing.${RESET}"
    read -rp "Reboot now? [y/N]: " reboot_choice
    case "${reboot_choice,,}" in
        y|yes)
            echo
            echo "${RED}Rebooting now.${RESET}"
            sudo reboot
            ;;
        *)
            echo
            echo "${YELLOW}Skipping reboot. Make sure to reboot manually before continuing upgrades.${RESET}"
            exit 0
            ;;
    esac