#!/bin/bash
set -euo pipefail

##########################
# Color helpers (printf-safe, 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

say_red()    { printf "%b%s%b\n" "$RED" "$*" "$RESET"; }
say_green()    { printf "%b%s%b\n" "$GREEN" "$*" "$RESET"; }
say_yellow()   { printf "%b%s%b\n" "$YELLOW" "$*" "$RESET"; }
say_cyan()     { printf "%b%s%b\n" "$CYAN" "$*" "$RESET"; }
say_gray()     { printf "%b%s%b\n" "$GRAY" "$*" "$RESET"; }
say_bold()     { printf "%b%s%b\n" "$BOLD" "$*" "$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
say_cyan "Starting Debian setup..."
echo
say_gray "DE: $DE, TWM: $TWM, Install Level: $INSTALL_LEVEL"

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

##########################
# 1. Add contrib and non-free if missing
##########################
say_yellow "Checking /etc/apt/sources.list for contrib/non-free..."
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
say_green "Updated sources.list to include contrib/non-free where needed."

##########################
# 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
    say_yellow "Found archive.debian.org in sources.list and system is Bullseye or newer, updating to deb.debian.org..."
    sudo sed -i -r 's|archive\.debian\.org|deb.debian.org|g' /etc/apt/sources.list
    say_green "Updated sources.list to use deb.debian.org."
fi

##########################
# 2. Full update and upgrade
##########################
say_yellow "Updating package lists..."
sudo apt update

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

say_yellow "Upgrading installed packages..."
sudo apt -y full-upgrade

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

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

say_cyan "Current codename: $CURRENT_CODENAME"
say_cyan "Latest stable codename: $LATEST_CODENAME"

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
        say_red "Error: Cannot determine next codename after $CURRENT_CODENAME"
        exit 1
    fi

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

            say_yellow "Updating packages..."
            sudo apt update
            sudo apt -y autoremove || true
            sudo apt -y full-upgrade
            sudo apt -y autoremove || true

            say_green "Upgrade to $NEXT_CODENAME complete. A reboot is recommended."
            read -rp "Press Enter to reboot..." _
            sudo reboot
            ;;
        *)
            say_yellow "Skipping upgrade to $NEXT_CODENAME. Continuing with current version."
            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

say_green "Debian is now at codename $CURRENT_CODENAME. Continuing with DE/TWM installation..."

##########################
# 4. Desktop Environment installation
##########################
case "$DE" in
    xfce|plasma|gnome)
        say_yellow "Preparing to install $DE..."
        SCRIPT_NAME="$SCRIPT_DIR/${OS}-${DE}.sh"
        if [[ -f "$SCRIPT_NAME" ]]; then
            say_cyan "Running $SCRIPT_NAME..."
            bash "$SCRIPT_NAME"
        else
            say_red "Error: $SCRIPT_NAME not found!"
            exit 1
        fi
        ;;
    none)
        say_gray "No Desktop Environment selected, skipping DE installation."
        ;;
esac

##########################
# 5. Tiling Window Manager installation
##########################
case "$TWM" in
    chadwm|hyprland)
        say_yellow "Installing $TWM..."
        SCRIPT_NAME="$SCRIPT_DIR/${OS}-${TWM}.sh"
        if [[ -f "$SCRIPT_NAME" ]]; then
            say_cyan "Running $SCRIPT_NAME..."
            bash "$SCRIPT_NAME"
        else
            say_red "Error: $SCRIPT_NAME not found!"
            exit 1
        fi
        ;;
    none)
        say_gray "No tiling window manager selected."
        ;;
esac

##########################
# 6. Installation level handling
##########################
case "$INSTALL_LEVEL" in
    minimal|full|workstation|server)
        say_cyan "Installation level: $INSTALL_LEVEL"
        SCRIPT_NAME="$SCRIPT_DIR/${OS}-${INSTALL_LEVEL}.sh"
        if [[ -f "$SCRIPT_NAME" ]]; then
            say_cyan "Running $SCRIPT_NAME..."
            bash "$SCRIPT_NAME"
        else
            say_red "Error: $SCRIPT_NAME not found!"
            exit 1
        fi
        ;;
esac

say_green "Debian setup complete."
say_red "The installation has finished. A reboot is recommended before continuing."
read -rp "Reboot now? [y/N]: " reboot_choice
case "${reboot_choice,,}" in
    y|yes)
        say_red "Rebooting now."
        sudo reboot
        ;;
    *)
        say_yellow "Skipping reboot. Make sure to reboot manually before continuing upgrades."
        exit 0
        ;;
esac