#!/bin/bash
# auto-opencode-setup.sh - Configure auto-opencode session on login
# Usage: sudo ./auto-opencode-setup.sh [enable|disable] [graphical|multi-user] [auto-login]

set -euo pipefail

AUTO_OPENCODE_DIR="$HOME/.config/auto-opencode"
AUTO_OPENCODE_SCRIPT="$AUTO_OPENCODE_DIR/auto-opencode.sh"
AUTO_OPENCODE_MARKER="$AUTO_OPENCODE_DIR/enabled"
AUTO_LOGIN_MARKER="$AUTO_OPENCODE_DIR/auto-login"
TARGET_MARKER="$AUTO_OPENCODE_DIR/target"

log_info() { echo -e "\033[0;34m[INFO]\033[0m $1"; }
log_ok() { echo -e "\033[0;32m[OK]\033[0m $1"; }
log_warn() { echo -e "\033[1;33m[WARN]\033[0m $1"; }
log_error() { echo -e "\033[0;31m[ERROR]\033[0m $1"; }

usage() {
    cat <<EOF
Usage: $0 [enable|disable] [graphical|multi-user] [auto-login] [auto-opencode]

Configure auto-opencode session on login.

Commands:
  enable  - Enable auto-opencode
  disable - Disable auto-opencode
  status  - Show current configuration

Options:
  graphical|multi-user  - Boot target (default: graphical)
  auto-login            - Enable automatic login (graphical: GDM, multi-user: getty)
  auto-opencode         - Start opencode tmux session on login

Examples:
  $0 enable graphical auto-login auto-opencode
  $0 enable multi-user auto-opencode
  $0 disable
  $0 status
EOF
}

create_auto_opencode_script() {
    mkdir -p "$AUTO_OPENCODE_DIR"
    
    cat > "$AUTO_OPENCODE_SCRIPT" <<'SCRIPTEOF'
#!/bin/bash
# auto-opencode.sh - Runs on login to start opencode tmux session
# This script is sourced from .zprofile (multi-user) or .xprofile (graphical)

AUTO_OPENCODE_DIR="$HOME/.config/auto-opencode"
AUTO_OPENCODE_MARKER="$AUTO_OPENCODE_DIR/enabled"
AUTO_LOGIN_MARKER="$AUTO_OPENCODE_DIR/auto-login"

# Check if auto-opencode is enabled
[[ -f "$AUTO_OPENCODE_MARKER" ]] || exit 0

# Prevent multiple runs
if [[ -n "$AUTO_OPENCODE_STARTED" ]]; then
    exit 0
fi
export AUTO_OPENCODE_STARTED=1

# Only run in interactive shells
[[ $- == *i* ]] || exit 0

# Check if tmux is available
command -v tmux &>/dev/null || exit 0
command -v opencode &>/dev/null || exit 0

# Check if we're already in tmux
[[ -n "$TMUX" ]] && exit 0

# Target directory
TARGET_DIR="__OPEN_IOV_PARENT__"

# Session name
SESSION_NAME="auto-opencode"

# Check if session already exists
if tmux has-session -t "$SESSION_NAME" 2>/dev/null; then
    echo "Attaching to existing $SESSION_NAME session..."
    exec tmux attach-session -t "$SESSION_NAME"
fi

# Create new tmux session with opencode
echo "Starting auto-opencode session..."
cd "$TARGET_DIR"

# Start tmux session
tmux new-session -d -s "$SESSION_NAME" -c "$TARGET_DIR" \
    "opencode --dangerously-skip-permissions"

# Wait a moment for opencode to start
sleep 2

# Send initial commands to read AGENTS.md and handoff
tmux send-keys -t "$SESSION_NAME" "cat AGENTS.md" Enter
sleep 1
tmux send-keys -t "$SESSION_NAME" "cat Handoff-vGPU-IO.md" Enter
sleep 1

# Attach to session
exec tmux attach-session -t "$SESSION_NAME"
SCRIPTEOF

    # Bake in the repo parent dir (resolved at setup time)
    local repo_parent
    repo_parent="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
    sed -i "s|__OPEN_IOV_PARENT__|$repo_parent|g" "$AUTO_OPENCODE_SCRIPT"
    chmod +x "$AUTO_OPENCODE_SCRIPT"
    log_ok "Created auto-opencode script: $AUTO_OPENCODE_SCRIPT"
}

setup_graphical_autologin() {
    log_info "Setting up graphical auto-login (GDM)..."
    
    # Create GDM custom.conf for auto-login
    sudo mkdir -p /etc/gdm3
    sudo tee /etc/gdm3/custom.conf > /dev/null <<EOF
[daemon]
AutomaticLoginEnable=true
AutomaticLogin=${USER}
WaylandEnable=false

[security]

[xdmcp]

[chooser]

[debug]
EOF
    
    # Add auto-opencode to graphical session startup
    mkdir -p $HOME/.config/autostart
    cat > $HOME/.config/autostart/auto-opencode.desktop <<EOF
[Desktop Entry]
Type=Application
Name=Auto OpenCode
Exec=$HOME/.config/auto-opencode/auto-opencode.sh
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
EOF
    
    log_ok "Graphical auto-login configured"
}

setup_multiuser_autologin() {
    log_info "Setting up multi-user auto-login (getty)..."
    
    # Create systemd override for getty@tty1
    sudo mkdir -p /etc/systemd/system/getty@tty1.service.d
    sudo tee /etc/systemd/system/getty@tty1.service.d/autologin.conf > /dev/null <<EOF
[Service]
ExecStart=
ExecStart=-/sbin/agetty --autologin rmcore --noclear %I \$TERM
EOF
    
    # Add auto-opencode to .zprofile for multi-user login
    if ! grep -q "auto-opencode.sh" $HOME/.zprofile 2>/dev/null; then
        cat >> $HOME/.zprofile <<'EOF'

# Auto-opencode on login
if [[ -f $HOME/.config/auto-opencode/auto-opencode.sh ]]; then
    source $HOME/.config/auto-opencode/auto-opencode.sh
fi
EOF
    fi
    
    log_ok "Multi-user auto-login configured"
}

disable_autologin() {
    log_info "Disabling auto-login..."
    
    # Remove GDM auto-login
    if [[ -f /etc/gdm3/custom.conf ]]; then
        sudo sed -i '/^AutomaticLoginEnable=/d' /etc/gdm3/custom.conf
        sudo sed -i '/^AutomaticLogin=/d' /etc/gdm3/custom.conf
    fi
    
    # Remove getty auto-login
    sudo rm -f /etc/systemd/system/getty@tty1.service.d/autologin.conf
    
    # Remove autostart desktop entry
    rm -f $HOME/.config/autostart/auto-opencode.desktop
    
    # Remove from .zprofile
    sed -i '/auto-opencode.sh/d' $HOME/.zprofile 2>/dev/null || true
    
    log_ok "Auto-login disabled"
}

enable_auto_opencode() {
    local target="${1:-graphical}"
    local auto_login="${2:-false}"
    local auto_opencode="${3:-false}"
    
    log_info "Enabling auto-opencode (target: $target, auto-login: $auto_login, auto-opencode: $auto_opencode)"
    
    create_auto_opencode_script
    
    # Set target
    echo "$target" > "$TARGET_MARKER"
    
    # Set boot target
    sudo systemctl set-default "$target.target"
    log_ok "Boot target set to $target.target"
    
    # Handle auto-login
    if [[ "$auto_login" == "true" ]]; then
        touch "$AUTO_LOGIN_MARKER"
        if [[ "$target" == "graphical" ]]; then
            setup_graphical_autologin
        else
            setup_multiuser_autologin
        fi
    else
        rm -f "$AUTO_LOGIN_MARKER"
        disable_autologin
    fi
    
    # Handle auto-opencode
    if [[ "$auto_opencode" == "true" ]]; then
        touch "$AUTO_OPENCODE_MARKER"
        log_ok "Auto-opencode enabled"
    else
        rm -f "$AUTO_OPENCODE_MARKER"
        log_ok "Auto-opencode disabled"
    fi
    
    log_ok "Configuration complete"
}

disable_auto_opencode() {
    log_info "Disabling auto-opencode..."
    
    rm -f "$AUTO_OPENCODE_MARKER"
    rm -f "$AUTO_LOGIN_MARKER"
    rm -f "$TARGET_MARKER"
    
    disable_autologin
    
    # Remove auto-opencode script
    rm -f "$AUTO_OPENCODE_SCRIPT"
    
    log_ok "Auto-opencode disabled"
}

show_status() {
    echo "═══════════════════════════════════════════════════════════════"
    echo "  AUTO-OPENCODE STATUS"
    echo "═══════════════════════════════════════════════════════════════"
    
    if [[ -f "$AUTO_OPENCODE_MARKER" ]]; then
        echo "  Auto-opencode: ENABLED"
    else
        echo "  Auto-opencode: DISABLED"
    fi
    
    if [[ -f "$AUTO_LOGIN_MARKER" ]]; then
        echo "  Auto-login:    ENABLED"
    else
        echo "  Auto-login:    DISABLED"
    fi
    
    if [[ -f "$TARGET_MARKER" ]]; then
        echo "  Boot target:   $(cat "$TARGET_MARKER")"
    else
        echo "  Boot target:   $(systemctl get-default | sed 's/.target$//')"
    fi
    
    echo "  Current default: $(systemctl get-default)"
    echo "═══════════════════════════════════════════════════════════════"
}

main() {
    local action="${1:-status}"
    shift || true
    
    local target="graphical"
    local auto_login="false"
    local auto_opencode="false"
    
    # Parse remaining arguments
    for arg in "$@"; do
        case "$arg" in
            graphical|multi-user)
                target="$arg"
                ;;
            auto-login|auto-login=on)
                auto_login="true"
                ;;
            auto-login=off)
                auto_login="false"
                ;;
            auto-opencode|auto-opencode=on)
                auto_opencode="true"
                ;;
            auto-opencode=off)
                auto_opencode="false"
                ;;
            *)
                log_warn "Unknown argument: $arg"
                ;;
        esac
    done
    
    case "$action" in
        enable)
            enable_auto_opencode "$target" "$auto_login" "$auto_opencode"
            ;;
        disable)
            disable_auto_opencode
            ;;
        status)
            show_status
            ;;
        *)
            usage
            exit 1
            ;;
    esac
}

main "$@"