#!/bin/bash

# Bootloader management module for bootc image creation
# This module handles GRUB installation and configuration

# Common functions are sourced by the main script

# Install GRUB bootloader
install_grub_bootloader() {
    log_info "Installing bootloader..."
    
    # Check if kernel exists
    if [ -f "$WORK_DIR/mnt/boot/vmlinuz-6.12.41+deb13-amd64" ]; then
        log_info "Kernel found in /boot location"
        KERNEL_PATH="boot/vmlinuz-6.12.41+deb13-amd64"
        INITRD_PATH="boot/initrd.img-6.12.41+deb13-amd64"
    elif [ -f "$WORK_DIR/mnt/usr/lib/ostree-boot/vmlinuz-6.12.41+deb13-amd64" ]; then
        log_info "Kernel found in OSTree location"
        KERNEL_PATH="usr/lib/ostree-boot/vmlinuz-6.12.41+deb13-amd64"
        INITRD_PATH="usr/lib/ostree-boot/initrd.img-6.12.41+deb13-amd64"
    else
        log_error "Kernel not found in expected locations"
        log_info "Searching for kernel files..."
        find "$WORK_DIR/mnt" -name "*vmlinuz*" -o -name "*kernel*" 2>/dev/null | head -10
        exit 1
    fi
    
    # Install GRUB bootloader
    log_info "Installing GRUB bootloader..."
    
    # Create GRUB directory
    sudo mkdir -p "$WORK_DIR/mnt/boot/grub"
    
    # Temporarily unmount and remount for safer GRUB installation
    log_info "Temporarily unmounting filesystem for GRUB installation..."
    sudo umount "$WORK_DIR/mnt"
    
    # Get the loop device from the disk module
    if [ -z "$loop_dev" ]; then
        log_error "Loop device not set. Cannot install bootloader."
        return 1
    fi
    
    # Ensure the loop device path is correct
    local device_path="${loop_dev}"
    if [[ "$device_path" == /dev/* ]]; then
        device_path="${device_path#/dev/}"
    fi
    
    log_info "Loop device: $loop_dev, device path: $device_path"
    log_info "Mounting partition /dev/${device_path}p2"
    sudo mount "/dev/${device_path}p2" "$WORK_DIR/mnt"
    
    # Install GRUB to the disk
    log_info "Installing GRUB to /dev/$device_path..."
    if sudo grub-install --target=i386-pc --boot-directory="$WORK_DIR/mnt/boot" "/dev/$device_path"; then
        log_info "GRUB installed successfully"
    else
        log_warn "GRUB installation failed, trying alternative method..."
        # Try installing to the partition instead
        if sudo grub-install --target=i386-pc --boot-directory="$WORK_DIR/mnt/boot" "/dev/${device_path}p2"; then
            log_info "GRUB installed to partition successfully"
        else
            log_error "GRUB installation failed completely"
            return 1
        fi
    fi
    
    # Create GRUB configuration
    log_info "Creating GRUB configuration..."
    sudo tee "$WORK_DIR/mnt/boot/grub/grub.cfg" > /dev/null << EOF
set timeout=5
set default=0

menuentry "Debian Bootc" {
    linux /$KERNEL_PATH root=/dev/sda2 rw console=tty0 console=ttyS0,115200n8
    initrd /$INITRD_PATH
}
EOF
    
    log_info "Bootloader installation completed"
}

# Install systemd-boot (for UEFI systems)
install_systemd_boot() {
    log_info "Installing systemd-boot..."
    
    # Create bootloader entries directory
    sudo mkdir -p "$WORK_DIR/mnt/boot/loader/entries"
    
    # Create bootloader entry
    sudo tee "$WORK_DIR/mnt/boot/loader/entries/debian-bootc.conf" > /dev/null << EOF
title Debian Bootc
version 1
linux /ostree/debian-bootc/vmlinuz-6.12.41+deb13-amd64
initrd /ostree/debian-bootc/initramfs-6.12.41+deb13-amd64.img
options ostree=/ostree/boot.0/debian-bootc/0 rw console=tty0 console=ttyS0,115200n8
EOF
    
    # Create loader configuration
    sudo tee "$WORK_DIR/mnt/boot/loader/loader.conf" > /dev/null << EOF
default debian-bootc
timeout 5
editor no
EOF
    
    log_info "systemd-boot installation completed"
}

# Verify bootloader installation
verify_bootloader() {
    log_info "Verifying bootloader installation..."
    
    # Check GRUB configuration
    if [ -f "$WORK_DIR/mnt/boot/grub/grub.cfg" ]; then
        log_info "GRUB configuration found"
    else
        log_error "GRUB configuration not found"
        return 1
    fi
    
    # Check GRUB core image
    if [ -f "$WORK_DIR/mnt/boot/grub/i386-pc/core.img" ]; then
        log_info "GRUB core image found"
    else
        log_warn "GRUB core image not found - bootloader may not work"
    fi
    
    # Check kernel and initrd
    if [ -f "$WORK_DIR/mnt/boot/vmlinuz-6.12.41+deb13-amd64" ]; then
        log_info "Kernel found: vmlinuz-6.12.41+deb13-amd64"
    else
        log_error "Kernel not found"
        return 1
    fi
    
    if [ -f "$WORK_DIR/mnt/boot/initrd.img-6.12.41+deb13-amd64" ]; then
        log_info "Initrd found: initrd.img-6.12.41+deb13-amd64"
    else
        log_error "Initrd not found"
        return 1
    fi
    
    log_info "Bootloader verification completed successfully"
    return 0
}

# Show bootloader information
show_bootloader_info() {
    log_info "Bootloader information:"
    
    echo "GRUB configuration:"
    if [ -f "$WORK_DIR/mnt/boot/grub/grub.cfg" ]; then
        cat "$WORK_DIR/mnt/boot/grub/grub.cfg"
    else
        echo "GRUB configuration not found"
    fi
    
    echo ""
    echo "Boot directory contents:"
    ls -la "$WORK_DIR/mnt/boot/"
    
    echo ""
    echo "GRUB directory contents:"
    if [ -d "$WORK_DIR/mnt/boot/grub" ]; then
        ls -la "$WORK_DIR/mnt/boot/grub/"
    else
        echo "GRUB directory not found"
    fi
}

# Customize GRUB configuration
customize_grub_config() {
    local custom_config="$1"
    
    if [ -n "$custom_config" ] && [ -f "$custom_config" ]; then
        log_info "Applying custom GRUB configuration..."
        sudo cp "$custom_config" "$WORK_DIR/mnt/boot/grub/grub.cfg"
        log_info "Custom GRUB configuration applied"
    else
        log_warn "No custom GRUB configuration provided or file not found"
    fi
}

# Set GRUB timeout
set_grub_timeout() {
    local timeout="${1:-5}"
    
    log_info "Setting GRUB timeout to ${timeout} seconds..."
    
    # Update the existing grub.cfg with new timeout
    sudo sed -i "s/set timeout=.*/set timeout=$timeout/" "$WORK_DIR/mnt/boot/grub/grub.cfg"
    
    log_info "GRUB timeout set to ${timeout} seconds"
}

# Add custom GRUB menu entries
add_grub_menu_entry() {
    local title="$1"
    local kernel_path="$2"
    local initrd_path="$3"
    local root_device="${4:-/dev/sda2}"
    local extra_params="${5:-}"
    
    log_info "Adding GRUB menu entry: $title"
    
    # Append to grub.cfg
    sudo tee -a "$WORK_DIR/mnt/boot/grub/grub.cfg" > /dev/null << EOF

menuentry "$title" {
    linux /$kernel_path root=$root_device rw console=tty0 console=ttyS0,115200n8 $extra_params
    initrd /$initrd_path
}
EOF
    
    log_info "GRUB menu entry added: $title"
}

# Print module usage
print_module_usage() {
    echo "Usage: source modules/bootloader.sh"
    echo "This module handles bootloader installation and configuration."
    echo ""
    echo "Available functions:"
    echo "  install_bootloader - Install GRUB bootloader"
    echo "  install_systemd_boot - Install systemd-boot (UEFI)"
    echo "  verify_bootloader - Verify bootloader installation"
    echo "  show_bootloader_info - Display bootloader information"
    echo "  customize_grub_config - Apply custom GRUB configuration"
    echo "  set_grub_timeout - Set GRUB timeout value"
    echo "  add_grub_menu_entry - Add custom GRUB menu entries"
    echo ""
    echo "Required variables:"
    echo "  WORK_DIR - Working directory for operations"
    echo "  loop_dev - Loop device for disk operations"
}