#!/bin/bash
# ------------------------------------------------------------------------------
# Disks and partitions manipulation function
# This file is part of the init.sh project
# Copyright (c) 2019-2024 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
}
export -f blank_disk
# ------------------------------------------------------------------------------


# ------------------------------------------------------------------------------
# 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
}
export -f is_blank
# ------------------------------------------------------------------------------


# ------------------------------------------------------------------------------
# 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.
# TODO: support extended partition for DOS type, add error if trying to create
# more than 4 primary partitions
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
}
export -f mkparts
# ------------------------------------------------------------------------------


# ------------------------------------------------------------------------------
# Generic caller for mkfs.* tools (not exported)
mkfs_gen()
{
    for drv in $@; do
	if [[ -b /dev/$drv ]]; then
	    $mkfstool $MKFSOPT /dev/$drv
	else
	    prnt E "/dev/$drv is not a bloc device!"
	    die 18
	fi
    done
}
export -f mkfs_gen
# ------------------------------------------------------------------------------


# ------------------------------------------------------------------------------
# Format drive using ext4 filesystem, parameters will be a list of block device
mkext4()
{
    export mkfstool="mkfs.ext4"
    mkfs_gen $@
    unset mkfstool
}
export -f mkext4
# ------------------------------------------------------------------------------


# ------------------------------------------------------------------------------
# Format a XFS filesystem...
mkxfs()
{
    export mkfstool="mkfs.xfs"
    mkfs_gen $@
    unset mkfstool
}
export -f mkxfs
# ------------------------------------------------------------------------------


# ------------------------------------------------------------------------------
# ... NTFS ...
mkntfs()
{
    export mkfstool="mkfs.ntfs"
    mkfs_gen $@
    unset mkfstool
}
export -f mkntfs
# ------------------------------------------------------------------------------


# ------------------------------------------------------------------------------
# ... FAT32 ...
mkfat32()
{
    export mkfstool="mkfs.vfat"
    mkfs_gen $@
    unset mkfstool
}
export -f mkfat32
# ------------------------------------------------------------------------------


# ------------------------------------------------------------------------------
# ... BTRFS ...
mkbtrfs()
{
    export mkfstool="mkfs.btrfs"
    mkfs_gen $@
    unset mkfstool
}
export -f mkbtrfs
# ------------------------------------------------------------------------------


# EOF