#!/usr/bin/env bash
# Test: 10 % packet loss does not corrupt transferred data
#
# Injects 10 % packet loss via tc netem, reads a 500 KB file through the
# FUSE mount, and verifies the content matches the original on the NAS.
# rclone's SFTP retries and TCP retransmissions should compensate for the
# loss so the application sees correct data.
set -euo pipefail
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
source "$SCRIPT_DIR/../harness/helpers.sh"
source "$SCRIPT_DIR/../harness/mock-nas.sh"

require_root
setup_test_env
trap teardown_test_env EXIT

# --- Arrange ---
start_mock_nas
nas_create_file "data.dat" 500              # 500 KB

# Capture the NAS-side checksum before any network impairment
expected_cksum=$(nas_file_checksum "data.dat")

gen_config

start_warpgate
wait_for_mount
wait_for_rc_api

# --- Act ---
# Inject 10 % packet loss
inject_packet_loss 10

# Read the file through the FUSE mount
cat "$TEST_MOUNT/data.dat" > /dev/null

# --- Assert ---
# Verify the content read through the mount matches the NAS original
actual_cksum=$(md5sum "$TEST_MOUNT/data.dat" | awk '{print $1}')

if [[ "$actual_cksum" != "$expected_cksum" ]]; then
    echo "FAIL: checksum mismatch under 10% packet loss" >&2
    echo "  expected: $expected_cksum" >&2
    echo "  actual:   $actual_cksum" >&2
    clear_network_injection
    exit 1
fi

# Clean up tc rules
clear_network_injection

echo "PASS: $(basename "$0" .sh)"