#!/bin/sh /etc/rc.common

START=03

LOG_FILE="/tmp/mount-fix.log"

start() {
    # Initialize log
    rm -f "$LOG_FILE" >/dev/null 2>&1
    touch "$LOG_FILE"

    # Redirect all output (stdout and stderr) to the log file
    exec >>"$LOG_FILE" 2>&1

    echo "Begin mount fix process to make a usable userspace."

    # Determine firmware scenario
    if mount | grep -q "/usrdata"; then
        echo "New firmware scenario detected (with /usrdata)."
        handle_new_firmware
    elif mount | grep -q "/overlay"; then
        echo "Old firmware scenario detected (with /overlay)."
        handle_old_firmware
    else
        echo "Error: Unable to detect firmware scenario. Neither /usrdata nor /overlay mounts found. Exiting."
        exit 1
    fi
}

handle_old_firmware() {
    # Redirect all output (stdout and stderr) to the log file
    exec >>"$LOG_FILE" 2>&1
    /bin/echo "Begin mount fix process to make a usable userspace"

    # Forcefully unmount /etc
    /bin/echo "Unmounting the tiny overlay at /etc"
    /bin/umount -lf /etc >/dev/null 2>&1

    # Remount root filesystem as read-write
    /bin/echo "Remounting / as read-write"
    /bin/mount -o remount,rw /

    # Check if /overlay/etc-upper/merged.done exists
    /bin/echo "First time this is ran the stuff you have been putting in the old overlay needs merged."
    /bin/echo "Looking for evidence that this has already happened..."
    if [ ! -f /overlay/etc-upper/merged.done ]; then
        /bin/echo "/overlay/etc-upper/merged.done not found, merging /overlay/etc-upper/* to /etc/"
        cp -rf /overlay/etc-upper/* /etc/
        /bin/touch /overlay/etc-upper/merged.done
    else
        /bin/echo "/overlay/etc-upper/merged.done found, skipping merge"
    fi

    # Unmount /overlay
    /bin/echo "Unmounting the no longer needed /overlay"
    /bin/umount /overlay

    # Check if /etc/opkg.conf has a line containing "option overlay_root /overlay" and remove it if it exists
    /bin/echo "Lets be sure your opkg config isn't using the old overlay"
    if grep -q "option overlay_root /overlay" /etc/opkg.conf; then
        /bin/echo "Removing 'option overlay_root /overlay' from /etc/opkg.conf"
        sed -i '/option overlay_root \/overlay/d' /etc/opkg.conf
    else
        /bin/echo "'option overlay_root /overlay' not found in /etc/opkg.conf, no changes made"
    fi

    # Ensure necessary directories exist for overlay and pivot_root
    /bin/echo "Creating new overlay system"
    if [ ! -d /data/rootfs ]; then
        mkdir -p /data/rootfs
    fi
    if [ ! -d /data/rootfs-workdir ]; then
        mkdir -p /data/rootfs-workdir
    fi
    if [ ! -d /rootfs ]; then
        mkdir -p /rootfs
    fi

    # Mount the new overlay filesystem
    /bin/mount -t overlay overlay -o lowerdir=/,upperdir=/data/rootfs,workdir=/data/rootfs-workdir /rootfs

    # Create the real_rootfs directory in the new root
    if [ ! -d /rootfs/real_rootfs ]; then
        mkdir -p /rootfs/real_rootfs
    fi

    # Pivot root to the new root
    /bin/echo "Pivoting Root / to /rootfs; Be back soon!!"
    /sbin/pivot_root /rootfs /rootfs/real_rootfs >/dev/null 2>&1

    # Move the mounted filesystems to the new locations
    /bin/mount --move /real_rootfs/sys /sys
    /bin/mount --move /real_rootfs/proc /proc
    /bin/mount --move /real_rootfs/tmp /tmp
    /bin/mount --move /real_rootfs/dev /dev
    /bin/mount --move /real_rootfs/firmware /firmware
    /bin/mount --move /real_rootfs/persist /persist
    /bin/mount --move /real_rootfs/cache /cache
    /bin/mount --move /real_rootfs/data /data

    # Synchronize between /etc/rc.d and /real_rootfs/etc/rc.d
    synchronize_rc_d "/etc/rc.d" "/real_rootfs/etc/rc.d"

    # Final logs and remount the original root as read-only
    /bin/echo "...and we're back! The original root now lives at /real_rootfs"
    /bin/echo "Lets mount it as read-only for now, If you need it just remount it as read-write"
    /bin/mount -o remount,ro /real_rootfs >/dev/null 2>&1
    /bin/echo "Overlay and pivot_root setup completed"
}

handle_new_firmware() {
    # Redirect all output (stdout and stderr) to the log file
    exec >>"$LOG_FILE" 2>&1
    /bin/echo "Begin mount fix process to make a usable userspace"

    # Forcefully unmount /etc
    /bin/echo "Unmounting the 2 mounts over /etc"
    /bin/umount -lf /etc >/dev/null 2>&1
    /bin/umount -lf /etc >/dev/null 2>&1

    # Remount root filesystem as read-write
    /bin/echo "Remounting / as read-write"
    /bin/mount -o remount,rw /

    # Begin layer merge checks
    # Layer 1 to 2
    # Check if /overlay/etc-upper/merged.done exists
    /bin/echo "First time this is ran the stuff you have been putting in the old overlay and /usrdata/etc needs merged."
    /bin/echo "Looking for evidence that this has already happened..."
    if [ ! -f /usrdata/overlay-work/etc-upper/merged.done ]; then
        /bin/echo "/usrdata/overlay-work/etc-upper/merged.done not found, merging /usrdata/overlay-work/etc-upper/* to /usrdata/etc/"
        cp -rf /usrdata/overlay-work/etc-upper/* /usrdata/etc/
        /bin/touch /usrdata/overlay-work/etc-upper/merged.done
    else
        /bin/echo "/usrdata/overlay-work/etc-upper/merged.done found, skipping merge"
    fi
    # Layer 2 to 3
    # Check if /usrdata/etc/merged.done exists
    /bin/echo "First time this is ran the stuff you have been putting in /usrdata/etc and /etc needs merged."
    /bin/echo "Looking for evidence that this has already happened..."
    if [ ! -f /usrdata/etc/merged.done ]; then
        /bin/echo "/usrdata/etc/merged.done not found, merging /usrdata/etc/* to /etc/"
        cp -rf /usrdata/etc/* /etc/
        /bin/touch /usrdata/etc/merged.done
    else
        /bin/echo "/usrdata/etc/merged.done found, skipping merge"
    fi


    # Check if /etc/opkg.conf has a line containing "option overlay_root /overlay" and remove it if it exists
    /bin/echo "Lets be sure your opkg config isn't using the old overlay"
    if grep -q "option overlay_root /overlay" /etc/opkg.conf; then
        /bin/echo "Removing 'option overlay_root /overlay' from /etc/opkg.conf"
        sed -i '/option overlay_root \/overlay/d' /etc/opkg.conf
    else
        /bin/echo "'option overlay_root /overlay' not found in /etc/opkg.conf, no changes made"
    fi

    # Ensure necessary directories exist for overlay and pivot_root
    /bin/echo "Creating new overlay system"
    if [ ! -d /usrdata/rootfs ]; then
        mkdir -p /usrata/rootfs
    fi
    if [ ! -d /usrdata/rootfs-workdir ]; then
        mkdir -p /usrdata/rootfs-workdir
    fi
    if [ ! -d /rootfs ]; then
        mkdir -p /rootfs
    fi

    # Mount the new overlay filesystem
    /bin/mount -t overlay overlay -o lowerdir=/,upperdir=/usrdata/rootfs,workdir=/usrdata/rootfs-workdir /rootfs

    # Create the real_rootfs directory in the new root
    if [ ! -d /rootfs/real_rootfs ]; then
        mkdir -p /rootfs/real_rootfs
    fi

    # Pivot root to the new root
    /bin/echo "Pivoting Root / to /rootfs; Be back soon!!"
    /sbin/pivot_root /rootfs /rootfs/real_rootfs >/dev/null 2>&1

    # Move the mounted filesystems to the new locations
    /bin/mount --move /real_rootfs/sys /sys
    /bin/mount --move /real_rootfs/proc /proc
    /bin/mount --move /real_rootfs/tmp /tmp
    /bin/mount --move /real_rootfs/dev /dev
    /bin/mount --move /real_rootfs/firmware /firmware
    /bin/mount --move /real_rootfs/usrdata /usrdata
    /bin/mount --move /real_rootfs/data /data
    /bin/mount --move /real_rootfs/cache /cache
    /bin/mount --move /real_rootfs/systemrw /systemrw
    /bin/mount --move /real_rootfs/persist /persist


    # Synchronize between /etc/rc.d and /real_rootfs/etc/rc.d
    synchronize_rc_d "/etc/rc.d" "/real_rootfs/etc/rc.d"

    # Synchronize between /etc/rc.d and /usrdata/etc/rc.d
    synchronize_rc_d "/etc/rc.d" "/usrdata/etc/rc.d"

    # Final logs and remount the original root as read-only
    /bin/echo "...and we're back! The original root now lives at /real_rootfs"
    /bin/echo "Lets mount it as read-only for now, If you need it just remount it as read-write"
    /bin/mount -o remount,ro /real_rootfs >/dev/null 2>&1
    /bin/echo "Overlay and pivot_root setup completed"

}


synchronize_rc_d() {
    local source_dir="$1"
    local target_dir="$2"

    /bin/echo "Synchronizing $source_dir with $target_dir"
    for link in "$source_dir"/*; do
        if [ -L "$link" ]; then
            link_name=$(basename "$link")
            if [ ! -e "$target_dir/$link_name" ]; then
                /bin/echo "Copying $link_name to $target_dir"
                cp -a "$link" "$target_dir/$link_name"
            fi
        fi
    done

    for link in "$target_dir"/*; do
        if [ -L "$link" ]; then
            link_name=$(basename "$link")
            if [ ! -e "$source_dir/$link_name" ]; then
                /bin/echo "Removing $link_name from $target_dir"
                rm "$target_dir/$link_name"
            fi
        fi
    done
}

stop() {
    # Initialize log
    rm -f "$LOG_FILE" >/dev/null 2>&1
    touch "$LOG_FILE"
    # Redirect all output (stdout and stderr) to the log file
    exec >>"$LOG_FILE" 2>&1
    
    # Check if /real_rootfs exists
    if [ ! -d "/real_rootfs" ]; then
        echo "Error: /real_rootfs does not exist. Cannot proceed with stop." >> "$LOG_FILE"
        return 1
    fi

    # Determine firmware version based on mounts
    if [ -d "/usrdata" ] && [ -d "/systemrw" ]; then
        echo "New firmware scenario detected (with /usrdata and /systemrw)." >> "$LOG_FILE"
        stop_handle_new_firmware
    else
        echo "Old firmware scenario detected (without /usrdata and /systemrw)." >> "$LOG_FILE"
        stop_handle_old_firmware
    fi
}

stop_handle_new_firmware() {
    # Redirect all output (stdout and stderr) to the log file
    exec >>"$LOG_FILE" 2>&1
    /bin/echo "Stopping and reverting overlay and pivot_root"

    # Remount the original root filesystem as read-write
    /bin/mount -o remount,rw /real_rootfs

    # Move the mounted filesystems back to the original locations
    /bin/mount --move /sys /real_rootfs/sys
    /bin/mount --move /proc /real_rootfs/proc
    /bin/mount --move /tmp /real_rootfs/tmp
    /bin/mount --move /dev /real_rootfs/dev
    /bin/mount --move /firmware /real_rootfs/firmware
    /bin/mount --move /usrdata /real_rootfs/usrdata
    /bin/mount --move /data /real_rootfs/data
    /bin/mount --move /cache /real_rootfs/cache
    /bin/mount --move /systemrw /real_rootfs/systemrw
    /bin/mount --move /persist /real_rootfs/persist

    # Pivot root back to the original root
    /sbin/pivot_root /real_rootfs /real_rootfs/rootfs

    /bin/echo "Reverted pivot_root"
	
	# Unmount /rootfs overlay
	/bin/umount -lf /rootfs >/dev/null 2>&1
	
	# Mount layer 2 /etc back
    /bin/mount -t ubifs -o rw,relatime,bulk_read,assert=read-only,ubi=2,vol=0 /dev/ubi2_0 /etc

    # Mount layer 3 /etc back
    /bin/mount -t overlay overlay -o lowerdir=/etc,upperdir=/usrdata/overlay-work/etc-upper,workdir=/usrdata/overlay-work/.etc-work /etc
	df -h
	echo -e "\e[31m / is read-write right now. Be careful\e[0m"
	echo -e "\e[31m Reboot or run mount -o remount,ro / \e[0m"
}

stop_handle_old_firmware() {
    # Redirect all output (stdout and stderr) to the log file
    exec >>"$LOG_FILE" 2>&1
    /bin/echo "Stopping and reverting overlay and pivot_root" 

    # Remount the original root filesystem as read-write
    /bin/mount -o remount,rw /real_rootfs

    # Move the mounted filesystems back to the original locations
    /bin/mount --move /sys /real_rootfs/sys 
    /bin/mount --move /proc /real_rootfs/proc 
    /bin/mount --move /tmp /real_rootfs/tmp 
    /bin/mount --move /dev /real_rootfs/dev 
    /bin/mount --move /firmware /real_rootfs/firmware 
    /bin/mount --move /persist /real_rootfs/persist 
    /bin/mount --move /cache /real_rootfs/cache 
    /bin/mount --move /data /real_rootfs/data 

    # Pivot root back to the original root
    /sbin/pivot_root /real_rootfs /real_rootfs/rootfs 

    /bin/echo "Reverted pivot_root"
	
	# Unmount /rootfs overlay
	/bin/umount -lf /rootfs >/dev/null 2>&1
	
	# Mount the location of etc-upper back
	mount -t ubifs /dev/ubi0_3 /overlay
	
	# Mount the old overlay filesystem back for etc
    /bin/mount -t overlay overlay -o lowerdir=/etc,upperdir=/overlay/etc-upper,workdir=/overlay/.etc-work /etc 
	
	echo -e "\e[31m / is read-write right now. Be careful\e[0m"
	echo -e "\e[31m Reboot or run mount -o remount,ro / \e[0m"
}
}

restart() {
    /bin/echo "This script should only be executed once at boot"
    /bin/echo "Use Stop to undo the pivot"
	/bin/echo "Use Start to put it back"
}