# ------------------------------------------------------------------------------
# Disks and partitions manipulation function
# This file is part of the init.sh project
# Copyright (c) 2019-2021 Geoffray Levasseur <fatalerrors@geoffray-levasseur.org>
# ------------------------------------------------------------------------------
# This file is distributed under 3-clause BSD license.
# The complete license agreement can be obtained at:
# https://opensource.org/licenses/BSD-3-Clause
# ------------------------------------------------------------------------------


# ------------------------------------------------------------------------------
# Blank the given disks
blank_disk()
{
    if [[ -b /dev/$1 ]]; then
        prnt I "Wipping $1 drive signature (a backup is made in /root)..."
        wipefs --force --all --backup /dev/$1
        prnt I "Filling beginning of $1 drive with zeroes..."
        if [[ $2 == "--full" ]]; then
            # If full we display progress as it might take a very long time
            # Need true to avoid error as the last byte will generate a disk
            # full error
            dd if="/dev/zero" of="$1" bs="512" status=progress || true
        else
            dd if="/dev/zero" of="$1" bs="512" count="1024"
        fi

        # Update kernel partition scheme
        partprobe
    else
        prnt E "The /dev/$1 file is not a bloc device!"
        die 19
    fi
}


# ------------------------------------------------------------------------------
# Check if $1 is a blank block device. Return values:
# * 0 if empty block device
# * 1 if not empty block device
# * 2 if not block device or if it don't exists
is_blank()
{
    if [[ -b /dev/$1 ]]; then
        # That technique is fast but might not be relayable enough if we are on
        # exotic data structure or filesystem...
        local devstat=$(file /dev/$1 | sed "s@/dev/$1: @@")
        if [[ $devstat == 'data' ]]; then
            return 0
        else
            return 1
        fi
    else
        return 2
    fi
}

# ------------------------------------------------------------------------------
# Creating empty partitions
# mkparts <disk> [dos|gpt] [list_of_partition_size]
# Partition size like 10G for 10 GiB, 600M for 600 MiB and so on... Without unit
# it will use a number of cylinder. 0 will stand for all remaining size.
# If no partition size is provided we create a single whole disk partition.
mkparts()
{
    local device=$1 && shit
    if [[ $1 == "gtp" || $1 == "dos" ]]; then
        local parttype=$1 && shift
    else
        # Default is GPT
        local parttype="gpt"
    fi

    if [[ $(is_blank $device) ]]; then
        prnt I "Creating a new ${parttype^^} partition table on $device..."
        sfdisk -label /dev/$device $parttype
        prnt I "Creating a new partition scheme on /dev/$1..."
        local tmpfile=$(mktemp sfd.XXXX)
        if [[ -n $1 ]]; then
            # For each given size we make a partition
            for $part in $@; do
                # If size is zero we interpret it as all available space
                if [[ $part == 0 ]]; then
                    echo ",,L" >> $tmpfile
                else
                    echo ",$part,L" >> $tmpfile
                fi
            done
        else
            echo ",,L" >> $tmpfile
        fi
        echo "write" >> $tmpfile
        sfdisk "/dev/$device" < $tmpfile
        rm $tmpfile
        unset tmpfile
    else
        prnt E "The $1 block device is not blank, for security we won't proceed!"
        die 20
    fi
    unset device parttype
}

# ------------------------------------------------------------------------------
# Format drive using ext4 filesystem, parameters will be a list of block device
mkext4()
{
    for drv in $@; then
        if [[ -b /dev/$drv ]]; then
            mkfs.ext4 /dev/$drv
        else
            prnt E "/dev/$drv is not a bloc device!"
            die 18
        fi
    done
}

# ------------------------------------------------------------------------------
mkxfs()
{
    : # todo
}

# EOF