#!/bin/bash
# SPDX-License-Identifier: AGPL-3.0-or-later
# Copyright (c) 2025-2026 Cristian Cezar Moisés
# Property-based test for zupt dedup path.
# Generates random file sets with intentional duplicates, verifies that
# (a) compressed output is correct (byte-exact roundtrip) and
# (b) dedup actually saves space when duplicates are present.

ZUPT_BIN="$(realpath ./zupt)"
TMPDIR=$(mktemp -d)
trap "rm -rf $TMPDIR" EXIT
cd "$TMPDIR"

PASS=0; FAIL=0
chk() {
    if [ $? -eq 0 ]; then echo "  ✓ $1"; PASS=$((PASS+1))
    else echo "  ✗ $1"; FAIL=$((FAIL+1)); fi
}

# ─── Property 1: dedup roundtrip is byte-exact ──────────────────────────
# Generate 10 random base files + 5 exact duplicates; compress with --dedup;
# extract; verify every file matches its original.
echo "  [P1. Dedup roundtrip preserves all bytes]"

mkdir input
for i in $(seq 1 10); do
    dd if=/dev/urandom of=input/file_$i.bin bs=4K count=$((RANDOM % 8 + 1)) 2>/dev/null
done
# 5 exact duplicates (same content as file_1..5)
for i in 1 2 3 4 5; do
    cp input/file_$i.bin input/dup_$i.bin
done

"$ZUPT_BIN" c --dedup test_dedup.zupt input/*.bin > /dev/null 2>&1
chk "Compress with --dedup succeeds"

mkdir extracted && cd extracted
"$ZUPT_BIN" x ../test_dedup.zupt > /dev/null 2>&1
chk "Extract --dedup archive succeeds"

all_match=1
for i in $(seq 1 10); do
    if ! diff -q ../input/file_$i.bin tmp*/input/file_$i.bin > /dev/null 2>&1 \
       && ! diff -q ../input/file_$i.bin input/file_$i.bin > /dev/null 2>&1; then
        all_match=0; break
    fi
done
[ $all_match -eq 1 ]
chk "All 10 base files roundtrip byte-exact"

dup_match=1
for i in 1 2 3 4 5; do
    found=0
    for d in tmp*/input input; do
        if [ -f "$d/dup_$i.bin" ] && diff -q ../input/dup_$i.bin "$d/dup_$i.bin" > /dev/null 2>&1; then
            found=1; break
        fi
    done
    [ $found -eq 1 ] || { dup_match=0; break; }
done
[ $dup_match -eq 1 ]
chk "All 5 duplicate files roundtrip byte-exact"

cd ..

# ─── Property 2: dedup reduces size for duplicate-heavy workloads ───────
echo "  [P2. Dedup compresses better than non-dedup on duplicate-heavy data]"

mkdir dups
for i in $(seq 1 20); do
    cp input/file_1.bin dups/copy_$i.bin
done

"$ZUPT_BIN" c        no_dedup.zupt    dups/*.bin > /dev/null 2>&1
"$ZUPT_BIN" c --dedup  with_dedup.zupt  dups/*.bin > /dev/null 2>&1

size_no=$(stat -c%s no_dedup.zupt 2>/dev/null || stat -f%z no_dedup.zupt)
size_yes=$(stat -c%s with_dedup.zupt 2>/dev/null || stat -f%z with_dedup.zupt)

[ "$size_yes" -lt "$size_no" ]
chk "Dedup archive ($size_yes B) smaller than non-dedup ($size_no B)"

ratio=$(awk "BEGIN{printf \"%.0f\", $size_yes * 100 / $size_no}")
[ "$ratio" -lt 50 ]
chk "Dedup achieves >50% reduction (got $ratio% of original)"

# ─── Property 3: dedup roundtrip preserves data on duplicate-only sets ──
echo "  [P3. 100% duplicate file set extracts correctly]"

mkdir extr_dups && cd extr_dups
"$ZUPT_BIN" x ../with_dedup.zupt > /dev/null 2>&1
chk "Extract heavy-duplicate archive succeeds"

n_extracted=$(find . -name "copy_*.bin" 2>/dev/null | wc -l)
[ "$n_extracted" -eq 20 ]
chk "All 20 duplicate copies extracted (got $n_extracted)"

all_dup_match=1
for f in $(find . -name "copy_*.bin"); do
    if ! diff -q "$f" ../input/file_1.bin > /dev/null 2>&1; then
        all_dup_match=0; break
    fi
done
[ $all_dup_match -eq 1 ]
chk "All extracted duplicates byte-exact match the original"

cd ..

# ─── Property 4: dedup + encryption coexist correctly ───────────────────
echo "  [P4. Dedup + SDK encryption work together]"

"$ZUPT_BIN" keygen --sdk -o k.priv > /dev/null 2>&1
"$ZUPT_BIN" c --dedup --pq-sdk k.priv.pub enc_dedup.zupt dups/*.bin > /dev/null 2>&1
chk "Encrypt + dedup compress succeeds"

mkdir extr_enc && cd extr_enc
"$ZUPT_BIN" x --pq-sdk ../k.priv ../enc_dedup.zupt > /dev/null 2>&1
chk "Encrypt + dedup extract succeeds"

n=$(find . -name "copy_*.bin" 2>/dev/null | wc -l)
[ "$n" -eq 20 ]
chk "All 20 copies recovered after enc+dedup ($n found)"

cd ..

echo
echo "  ───────────────────────────────────────"
echo "  Dedup property results: $PASS passed, $FAIL failed"
echo "  ───────────────────────────────────────"
[ $FAIL -eq 0 ]