#!/bin/sh

test_description='multi-pack-indexes'
. ./test-lib.sh

objdir=.git/objects

midx_read_expect () {
        NUM_PACKS=$1
        NUM_OBJECTS=$2
        NUM_CHUNKS=$3
        OBJECT_DIR=$4
        EXTRA_CHUNKS="$5"
        {
                cat <<-EOF &&
                header: 4d494458 1 $NUM_CHUNKS $NUM_PACKS
                chunks: pack-names oid-fanout oid-lookup object-offsets$EXTRA_CHUNKS
                num_objects: $NUM_OBJECTS
                packs:
                EOF
                if test $NUM_PACKS -ge 1
                then
                        ls $OBJECT_DIR/pack/ | grep idx | sort
                fi &&
                printf "object-dir: $OBJECT_DIR\n"
        } >expect &&
        test-tool read-midx $OBJECT_DIR >actual &&
        test_cmp expect actual
}

test_expect_success 'write midx with no packs' '
        test_when_finished rm -f pack/multi-pack-index &&
        git multi-pack-index --object-dir=. write &&
        midx_read_expect 0 0 4 .
'

generate_objects () {
        i=$1
        iii=$(printf '%03i' $i)
        {
                test-tool genrandom "bar" 200 &&
                test-tool genrandom "baz $iii" 50
        } >wide_delta_$iii &&
        {
                test-tool genrandom "foo"$i 100 &&
                test-tool genrandom "foo"$(( $i + 1 )) 100 &&
                test-tool genrandom "foo"$(( $i + 2 )) 100
        } >deep_delta_$iii &&
        {
                echo $iii &&
                test-tool genrandom "$iii" 8192
        } >file_$iii &&
        git update-index --add file_$iii deep_delta_$iii wide_delta_$iii
}

commit_and_list_objects () {
        {
                echo 101 &&
                test-tool genrandom 100 8192;
        } >file_101 &&
        git update-index --add file_101 &&
        tree=$(git write-tree) &&
        commit=$(git commit-tree $tree -p HEAD</dev/null) &&
        {
                echo $tree &&
                git ls-tree $tree | sed -e "s/.* \\([0-9a-f]*\\)        .*/\\1/"
        } >obj-list &&
        git reset --hard $commit
}

test_expect_success 'create objects' '
        test_commit initial &&
        for i in $(test_seq 1 5)
        do
                generate_objects $i
        done &&
        commit_and_list_objects
'

test_expect_success 'write midx with one v1 pack' '
        pack=$(git pack-objects --index-version=1 $objdir/pack/test <obj-list) &&
        test_when_finished rm $objdir/pack/test-$pack.pack \
                $objdir/pack/test-$pack.idx $objdir/pack/multi-pack-index &&
        git multi-pack-index --object-dir=$objdir write &&
        midx_read_expect 1 18 4 $objdir
'

midx_git_two_modes () {
        git -c core.multiPackIndex=false $1 >expect &&
        git -c core.multiPackIndex=true $1 >actual &&
        test_cmp expect actual
}

compare_results_with_midx () {
        MSG=$1
        test_expect_success "check normal git operations: $MSG" '
                midx_git_two_modes "rev-list --objects --all" &&
                midx_git_two_modes "log --raw"
        '
}

test_expect_success 'write midx with one v2 pack' '
        git pack-objects --index-version=2,0x40 $objdir/pack/test <obj-list &&
        git multi-pack-index --object-dir=$objdir write &&
        midx_read_expect 1 18 4 $objdir
'

compare_results_with_midx "one v2 pack"

test_expect_success 'add more objects' '
        for i in $(test_seq 6 10)
        do
                generate_objects $i
        done &&
        commit_and_list_objects
'

test_expect_success 'write midx with two packs' '
        git pack-objects --index-version=1 $objdir/pack/test-2 <obj-list &&
        git multi-pack-index --object-dir=$objdir write &&
        midx_read_expect 2 34 4 $objdir
'

compare_results_with_midx "two packs"

test_expect_success 'add more packs' '
        for j in $(test_seq 11 20)
        do
                generate_objects $j &&
                commit_and_list_objects &&
                git pack-objects --index-version=2 $objdir/pack/test-pack <obj-list
        done
'

compare_results_with_midx "mixed mode (two packs + extra)"

test_expect_success 'write midx with twelve packs' '
        git multi-pack-index --object-dir=$objdir write &&
        midx_read_expect 12 74 4 $objdir
'

compare_results_with_midx "twelve packs"

# usage: corrupt_data <file> <pos> [<data>]
corrupt_data () {
        file=$1
        pos=$2
        data="${3:-\0}"
        printf "$data" | dd of="$file" bs=1 seek="$pos" conv=notrunc
}

# Force 64-bit offsets by manipulating the idx file.
# This makes the IDX file _incorrect_ so be careful to clean up after!
test_expect_success 'force some 64-bit offsets with pack-objects' '
        mkdir objects64 &&
        mkdir objects64/pack &&
        for i in $(test_seq 1 11)
        do
                generate_objects 11
        done &&
        commit_and_list_objects &&
        pack64=$(git pack-objects --index-version=2,0x40 objects64/pack/test-64 <obj-list) &&
        idx64=objects64/pack/test-64-$pack64.idx &&
        chmod u+w $idx64 &&
        corrupt_data $idx64 2999 "\02" &&
        midx64=$(git multi-pack-index --object-dir=objects64 write) &&
        midx_read_expect 1 63 5 objects64 " large-offsets"
'

test_done