#!/usr/bin/env bash
set -Eeuo pipefail

readonly PROJECT="niri-beyond-glass"
readonly NIRI_TAG="v26.04"
readonly XWS_TAG="v0.8.2"
readonly RUST_TOOLCHAIN="1.85.1"
readonly DMS_REV="069ddab041c738236a8910e4c39b65d9628d3018"
readonly NIXPKGS_REV="d407951447dcd00442e97087bf374aad70c04cea"
readonly ARCHIVE_URL="https://git.k1412.top/wuyang/niri-beyond-glass/archive/main.tar.gz"

wallpaper=""
config_only=0
dry_run=0
rebuild=0
source_dir="${NBG_SOURCE_DIR:-}"
tmp_dir=""
selected_wallpaper=""

usage() {
    cat <<'EOF'
用法：install.sh [选项]

  --wallpaper PATH  使用指定的静态壁纸
  --config-only     只更新配置（要求 DMS 运行层已经安装）
  --rebuild         强制重新编译 Niri 和 Xwayland Satellite
  --dry-run         显示将执行的主要步骤，不修改系统
  -h, --help        显示帮助
EOF
}

log() {
    printf '\033[1;36m[Niri]\033[0m %s\n' "$*"
}

die() {
    printf '\033[1;31m错误：\033[0m %s\n' "$*" >&2
    exit 1
}

run() {
    if (( dry_run )); then
        printf '+'
        printf ' %q' "$@"
        printf '\n'
    else
        "$@"
    fi
}

cleanup() {
    if [[ -n "$tmp_dir" && -d "$tmp_dir" ]]; then
        rm -rf "$tmp_dir"
    fi
}
trap cleanup EXIT

while (($#)); do
    case "$1" in
        --wallpaper)
            (($# >= 2)) || die "--wallpaper 缺少路径"
            wallpaper="$2"
            shift 2
            ;;
        --config-only)
            config_only=1
            shift
            ;;
        --rebuild)
            rebuild=1
            shift
            ;;
        --dry-run)
            dry_run=1
            shift
            ;;
        -h|--help)
            usage
            exit 0
            ;;
        *)
            die "未知参数：$1"
            ;;
    esac
done

[[ ${EUID:-$(id -u)} -ne 0 ]] || die "请用普通用户运行，脚本会在需要时调用 sudo。"
[[ -z "$wallpaper" || -f "$wallpaper" ]] || die "壁纸不存在：$wallpaper"

if [[ -r /etc/os-release ]]; then
    # shellcheck disable=SC1091
    . /etc/os-release
else
    die "无法识别操作系统。"
fi

if [[ "${ID:-}" != "ubuntu" || "${VERSION_ID:-}" != "24.04" ]]; then
    die "只支持 Ubuntu 24.04；当前是 ${PRETTY_NAME:-未知系统}。"
fi

case "$(uname -m)" in
    x86_64|aarch64) ;;
    *) die "目前只支持 x86_64 和 aarch64。" ;;
esac

fetch_source() {
    if [[ -n "$source_dir" ]]; then
        [[ -f "$source_dir/config/niri/config.kdl" ]] || die "NBG_SOURCE_DIR 不是有效源码目录。"
        return
    fi

    tmp_dir="$(mktemp -d)"
    log "下载配置仓库"
    curl -fL --retry 3 "$ARCHIVE_URL" -o "$tmp_dir/source.tar.gz"
    mkdir -p "$tmp_dir/source"
    tar -xzf "$tmp_dir/source.tar.gz" -C "$tmp_dir/source" --strip-components=1
    source_dir="$tmp_dir/source"
}

install_packages() {
    log "安装 Ubuntu 24.04 依赖"
    run sudo apt-get update
    run sudo env DEBIAN_FRONTEND=noninteractive apt-get install -y \
        build-essential clang git curl ca-certificates pkg-config \
        meson ninja-build cmake hwdata \
        libudev-dev libgbm-dev libxkbcommon-dev libegl1-mesa-dev \
        libwayland-dev libinput-dev libdbus-1-dev libsystemd-dev \
        libseat-dev libpipewire-0.3-dev libpango1.0-dev \
        libdisplay-info-dev libcairo2-dev libglib2.0-dev \
        libxcb1-dev libxcb-composite0-dev libxcb-randr0-dev \
        libxcb-res0-dev libxcb-xfixes0-dev libxcb-cursor-dev \
        xwayland xdg-desktop-portal-gnome xdg-desktop-portal-gtk \
        alacritty \
        nautilus policykit-1-gnome pipewire-pulse wireplumber \
        brightnessctl playerctl grim slurp wl-clipboard libnotify-bin \
        accountsservice jq nix-bin nix-setup-systemd \
        fonts-noto-core fonts-noto-cjk fonts-noto-color-emoji fonts-font-awesome \
        fonts-inter fonts-jetbrains-mono
}

install_dms_runtime() {
    local state_home="${XDG_STATE_HOME:-$HOME/.local/state}"
    local profile="$state_home/$PROJECT/nix-profile"
    local dms_flake="github:AvengeMedia/DankMaterialShell/$DMS_REV"
    local nixpkgs="github:NixOS/nixpkgs/$NIXPKGS_REV"

    if [[ -x "$profile/bin/dms" && -x "$profile/bin/quickshell" &&
          -x "$profile/bin/matugen" && -x "$profile/bin/dgop" &&
          -x "$profile/bin/dsearch" ]]; then
        log "DMS 运行层已经安装，跳过"
        return
    fi

    log "安装隔离的 DMS 1.5.3 与 Quickshell 0.3.0"
    run sudo usermod -aG nix-users "$USER"
    run sudo systemctl enable --now nix-daemon.socket
    run mkdir -p "$state_home/$PROJECT"

    if (( dry_run )); then
        printf '+ sudo -u %q -g nix-users nix profile install --profile %q ...\n' \
            "$USER" "$profile"
        return
    fi

    local attempt
    for attempt in 1 2 3 4 5; do
        if sudo -u "$USER" -g nix-users env \
            HOME="$HOME" USER="$USER" \
            NIX_CONFIG="experimental-features = nix-command flakes" \
            nix profile install --profile "$profile" \
                "$dms_flake#dms-shell" \
                "$nixpkgs#quickshell" \
                "$nixpkgs#matugen" \
                "$nixpkgs#dgop" \
                "$nixpkgs#dsearch"; then
            break
        fi
        (( attempt < 5 )) || die "DMS 运行层安装失败，请检查网络后重新运行脚本。"
        log "下载中断，正在重试（$attempt/5）"
        sleep 3
    done

    [[ -x "$profile/bin/dms" && -x "$profile/bin/quickshell" ]] ||
        die "DMS 或 Quickshell 安装不完整。"
}

install_rust() {
    export RUSTUP_HOME="${XDG_DATA_HOME:-$HOME/.local/share}/$PROJECT/rustup"
    export CARGO_HOME="${XDG_DATA_HOME:-$HOME/.local/share}/$PROJECT/cargo"
    export PATH="$CARGO_HOME/bin:$PATH"

    if [[ ! -x "$CARGO_HOME/bin/rustup" ]]; then
        log "安装隔离的 Rust $RUST_TOOLCHAIN 工具链"
        if (( dry_run )); then
            printf '+ curl https://sh.rustup.rs | sh -s -- -y --no-modify-path --profile minimal --default-toolchain %q\n' "$RUST_TOOLCHAIN"
            return
        fi
        local rustup_installer
        rustup_installer="$(mktemp)"
        curl --proto '=https' --tlsv1.2 -fsSL --retry 5 --retry-all-errors \
            https://sh.rustup.rs -o "$rustup_installer"
        RUSTUP_MAX_RETRIES=5 sh "$rustup_installer" -y --no-modify-path \
            --profile minimal --default-toolchain "$RUST_TOOLCHAIN"
        rm -f "$rustup_installer"
    elif ! "$CARGO_HOME/bin/rustup" run "$RUST_TOOLCHAIN" rustc --version >/dev/null 2>&1; then
        RUSTUP_MAX_RETRIES=5 run "$CARGO_HOME/bin/rustup" toolchain install \
            "$RUST_TOOLCHAIN" --profile minimal
    fi

    run "$CARGO_HOME/bin/rustup" set auto-self-update disable
    run "$CARGO_HOME/bin/rustup" default "$RUST_TOOLCHAIN"
}

version_ge() {
    [[ "$(printf '%s\n%s\n' "$2" "$1" | sort -V | head -n1)" == "$2" ]]
}

install_libdisplay_info() {
    local installed=""
    installed="$(pkg-config --modversion libdisplay-info 2>/dev/null || true)"
    if [[ -n "$installed" ]] && version_ge "$installed" "0.3.0"; then
        return
    fi

    log "编译 libdisplay-info 0.3.0（Ubuntu 24.04 自带版本较旧）"
    local build_root="${XDG_CACHE_HOME:-$HOME/.cache}/$PROJECT/build"
    local src="$build_root/libdisplay-info"
    run mkdir -p "$build_root"
    if [[ ! -d "$src/.git" ]]; then
        run git clone --depth 1 --branch 0.3.0 \
            https://gitlab.freedesktop.org/emersion/libdisplay-info.git "$src"
    fi
    run meson setup "$src/build" "$src" --prefix=/usr/local --buildtype=release --wipe
    run ninja -C "$src/build"
    run sudo ninja -C "$src/build" install
    run sudo ldconfig
}

install_niri() {
    local current=""
    current="$(niri --version 2>/dev/null || true)"
    if (( ! rebuild )) && [[ "$current" == *"26.4"* || "$current" == *"26.04"* ]]; then
        log "已安装兼容的 $current，跳过编译"
        return
    fi

    log "编译 Niri $NIRI_TAG"
    local build_root="${XDG_CACHE_HOME:-$HOME/.cache}/$PROJECT/build"
    local src="$build_root/niri"
    run mkdir -p "$build_root"
    if [[ ! -d "$src/.git" ]]; then
        run git clone --depth 1 --branch "$NIRI_TAG" https://github.com/niri-wm/niri.git "$src"
    else
        run git -C "$src" fetch --depth 1 origin "refs/tags/$NIRI_TAG:refs/tags/$NIRI_TAG"
        run git -C "$src" checkout -f "$NIRI_TAG"
    fi
    run cargo build --manifest-path "$src/Cargo.toml" --release --locked

    run sudo install -Dm755 "$src/target/release/niri" /usr/local/bin/niri
    run sudo install -Dm755 "$src/resources/niri-session" /usr/local/bin/niri-session
    run sudo install -Dm644 "$src/resources/niri.service" /usr/local/lib/systemd/user/niri.service
    run sudo install -Dm644 "$src/resources/niri-shutdown.target" /usr/local/lib/systemd/user/niri-shutdown.target
    run sudo install -Dm644 "$src/resources/niri.desktop" /usr/local/share/wayland-sessions/niri.desktop
    run sudo install -Dm644 "$src/resources/niri-portals.conf" /usr/local/share/xdg-desktop-portal/niri-portals.conf
}

install_xwayland_satellite() {
    if (( ! rebuild )) && command -v xwayland-satellite >/dev/null 2>&1; then
        return
    fi

    log "编译 Xwayland Satellite $XWS_TAG"
    local build_root="${XDG_CACHE_HOME:-$HOME/.cache}/$PROJECT/build"
    local src="$build_root/xwayland-satellite"
    run mkdir -p "$build_root"
    if [[ ! -d "$src/.git" ]]; then
        run git clone --depth 1 --branch "$XWS_TAG" \
            https://github.com/Supreeeme/xwayland-satellite.git "$src"
    else
        run git -C "$src" fetch --depth 1 origin "refs/tags/$XWS_TAG:refs/tags/$XWS_TAG"
        run git -C "$src" checkout -f "$XWS_TAG"
    fi
    run cargo build --manifest-path "$src/Cargo.toml" --release --locked
    run sudo install -Dm755 "$src/target/release/xwayland-satellite" /usr/local/bin/xwayland-satellite
}

backup_and_install_config() {
    local config_home="${XDG_CONFIG_HOME:-$HOME/.config}"
    local state_home="${XDG_STATE_HOME:-$HOME/.local/state}"
    local stamp
    stamp="$(date +%Y%m%d-%H%M%S)"
    local backup_root="$state_home/$PROJECT/backups/$stamp"
    local backup="$backup_root/config"
    local original="$state_home/$PROJECT/original"
    local names=(niri waybar fuzzel mako swaylock niri-beyond-glass DankMaterialShell alacritty)

    select_wallpaper "$config_home/niri-beyond-glass/wallpaper"

    log "备份并安装用户配置"
    run mkdir -p "$backup"
    local name
    for name in "${names[@]}"; do
        if [[ -e "$config_home/$name" ]]; then
            run cp -a "$config_home/$name" "$backup/$name"
        fi
    done
    if [[ -d "$state_home/DankMaterialShell" ]]; then
        run mkdir -p "$backup_root/state"
        run cp -a "$state_home/DankMaterialShell" "$backup_root/state/DankMaterialShell"
    fi

    run mkdir -p "$original/config" "$original/absent"
    for name in "${names[@]}"; do
        if [[ ! -e "$original/config/$name" && ! -e "$original/absent/$name" ]]; then
            if [[ -e "$config_home/$name" ]]; then
                run cp -a "$config_home/$name" "$original/config/$name"
            else
                run touch "$original/absent/$name"
            fi
        fi
    done
    run touch "$original/.captured"

    if (( dry_run )); then
        printf '+ install DMS, Niri and Alacritty style while preserving wallpaper %q\n' \
            "$selected_wallpaper"
        return
    fi

    mkdir -p \
        "$config_home/niri" \
        "$config_home/niri/dms" \
        "$config_home/niri-beyond-glass" \
        "$config_home/DankMaterialShell/themes" \
        "$config_home/alacritty" \
        "$config_home/systemd/user" \
        "$state_home/DankMaterialShell" \
        "$HOME/.local/bin" \
        "$HOME/Pictures/Screenshots"

    install -m644 "$source_dir/config/niri/config.kdl" "$config_home/niri/config.kdl"
    sed "s|__HOME__|$HOME|g" "$source_dir/config/niri/beyond-glass.kdl" \
        > "$config_home/niri/beyond-glass.kdl"
    install -m644 "$source_dir"/config/niri/dms/*.kdl "$config_home/niri/dms/"

    local theme_file="$config_home/DankMaterialShell/themes/beyond-glass.json"
    install -m644 "$source_dir/config/dms/beyond-glass.json" "$theme_file"

    local settings_tmp session_tmp
    settings_tmp="$(mktemp)"
    session_tmp="$(mktemp)"
    jq --arg wallpaper "$selected_wallpaper" --arg theme "$theme_file" '
        .customThemeFile = $theme
        | .greeterWallpaperPath = $wallpaper
        | .lockScreenWallpaperPath = $wallpaper
        | .lockScreenVideoPath = ""
    ' "$source_dir/config/dms/settings.json" > "$settings_tmp"
    jq --arg wallpaper "$selected_wallpaper" '
        .wallpaperPath = $wallpaper
        | .wallpaperPathLight = $wallpaper
        | .wallpaperPathDark = $wallpaper
        | .monitorWallpapers = {}
        | .monitorWallpapersLight = {}
        | .monitorWallpapersDark = {}
        | .perMonitorWallpaper = false
    ' "$source_dir/config/dms/session.json" > "$session_tmp"
    install -m644 "$settings_tmp" "$config_home/DankMaterialShell/settings.json"
    install -m644 "$session_tmp" "$state_home/DankMaterialShell/session.json"
    rm -f "$settings_tmp" "$session_tmp"
    touch "$config_home/DankMaterialShell/.firstlaunch" \
        "$config_home/DankMaterialShell/.changelog-1.5"

    install -m644 "$source_dir/config/alacritty/alacritty.toml" \
        "$config_home/alacritty/alacritty.toml"
    install -m644 "$source_dir/config/systemd/dms.service" \
        "$config_home/systemd/user/dms.service"
    install -m755 "$source_dir/scripts/niri-beyond-browser" \
        "$HOME/.local/bin/niri-beyond-browser"
    install -m755 "$source_dir/scripts/niri-beyond-refresh" \
        "$HOME/.local/bin/niri-beyond-refresh"

    local profile="$state_home/$PROJECT/nix-profile"
    local binary
    for binary in dms quickshell qs matugen dgop dsearch; do
        if [[ -x "$profile/bin/$binary" ]]; then
            ln -sfn "$profile/bin/$binary" "$HOME/.local/bin/$binary"
        fi
    done

    printf '%s\n' "$selected_wallpaper" > "$config_home/niri-beyond-glass/wallpaper"
}

select_wallpaper() {
    local state_file="$1"
    local selected="$wallpaper"

    if [[ -z "$selected" ]]; then
        local existing=""
        if [[ -r "$state_file" ]]; then
            existing="$(head -n1 "$state_file")"
        fi
        if [[ -n "$existing" && -f "$existing" ]]; then
            selected="$existing"
        fi
    fi

    if [[ -z "$selected" ]]; then
        local session="${XDG_STATE_HOME:-$HOME/.local/state}/DankMaterialShell/session.json"
        local existing=""
        if [[ -r "$session" ]]; then
            existing="$(jq -r '.wallpaperPath // empty' "$session" 2>/dev/null || true)"
        fi
        if [[ -n "$existing" && -f "$existing" ]]; then
            selected="$existing"
        fi
    fi

    if [[ -z "$selected" ]] && command -v gsettings >/dev/null 2>&1; then
        local uri=""
        uri="$(gsettings get org.gnome.desktop.background picture-uri-dark 2>/dev/null \
            | tr -d "'" || true)"
        uri="${uri#file://}"
        if [[ -n "$uri" && -f "$uri" ]]; then
            selected="$uri"
        fi
    fi

    if [[ -z "$selected" ]]; then
        local candidates=(
            /usr/share/backgrounds/warty-final-ubuntu.png
            /usr/share/backgrounds/ubuntu-default-greyscale-wallpaper.png
        )
        local candidate
        for candidate in "${candidates[@]}"; do
            if [[ -f "$candidate" ]]; then
                selected="$candidate"
                break
            fi
        done
    fi

    if [[ -z "$selected" ]]; then
        selected="$(find /usr/share/backgrounds -maxdepth 2 -type f \
            \( -iname '*.jpg' -o -iname '*.jpeg' -o -iname '*.png' \) \
            -print -quit 2>/dev/null || true)"
    fi

    [[ -n "$selected" && -f "$selected" ]] ||
        die "没有找到可用壁纸；可用 --wallpaper PATH 指定目标机上的图片。"
    selected_wallpaper="$selected"
    log "保留目标机壁纸：$selected_wallpaper"
}

activate_dms() {
    local profile="${XDG_STATE_HOME:-$HOME/.local/state}/$PROJECT/nix-profile"

    if (( dry_run )); then
        printf '+ stop legacy shell processes and enable dms.service\n'
        return
    fi

    if ! systemctl --user daemon-reload 2>/dev/null; then
        log "当前没有可用的 systemd 用户会话；DMS 将在下次 Niri 登录时启动"
        return
    fi
    systemctl --user disable --now waybar.service mako.service 2>/dev/null || true
    pkill -x waybar 2>/dev/null || true
    pkill -x mako 2>/dev/null || true
    pkill -x swaybg 2>/dev/null || true
    pkill -x swayidle 2>/dev/null || true
    systemctl --user enable dms.service

    "$profile/bin/dms" auth resolve-lock --quiet >/dev/null 2>&1 || true

    if [[ -n "${WAYLAND_DISPLAY:-}" ]]; then
        systemctl --user restart dms.service
    fi
}

validate_config() {
    if (( dry_run )); then
        printf '+ niri validate -c %q\n' "${XDG_CONFIG_HOME:-$HOME/.config}/niri/config.kdl"
        return
    fi
    command -v niri >/dev/null 2>&1 || die "找不到 niri，无法验证配置。"
    niri validate -c "${XDG_CONFIG_HOME:-$HOME/.config}/niri/config.kdl"
}

main() {
    fetch_source

    if (( ! config_only )); then
        install_packages
        install_rust
        install_libdisplay_info
        install_niri
        install_xwayland_satellite
        install_dms_runtime
    else
        local profile="${XDG_STATE_HOME:-$HOME/.local/state}/$PROJECT/nix-profile"
        [[ -x "$profile/bin/dms" && -x "$profile/bin/quickshell" ]] ||
            die "--config-only 需要先完成一次完整安装。"
    fi

    backup_and_install_config
    validate_config
    activate_dms

    log "安装完成"
    printf '\nDMS 个性化已迁移，目标机原壁纸和显示器布局未修改。\n'
    printf '当前若在 Niri 中，顶栏会自动重启；否则注销后选择“Niri”登录。\n'
    printf 'GNOME 和 GDM 均未修改；快捷键说明：Super+Shift+/。\n'
}

main