#!/bin/bash

set -u
set -o pipefail

fatal() {
    printf 'harness: %s\n' "$*" >&2
    exit 1
}

wait_for_docker() {
    attempts=30
    while [ "$attempts" -gt 0 ]; do
        docker info >/dev/null 2>&1 && return 0
        attempts=$((attempts - 1))
        sleep 1
    done
    return 1
}

cleanup() {
    docker ps -q --filter ancestor=hw3img | while IFS= read -r container_id; do
        [ -n "$container_id" ] || continue
        docker rm --force "$container_id" >/dev/null 2>&1 || true
    done
}

run_tests() {
    local arg
    local -a original_args=("$@")
    local -a test_args=(-docker -test.timeout=10m)
    while (($#)); do
        arg="$1"
        shift
        case "$arg" in
            -run|-count|-timeout|-parallel|-skip)
                if (($# == 0)); then
                    fatal "$arg requires a value"
                fi
                test_args+=("-test.${arg#-}" "$1")
                shift
                ;;
            -run=*|-count=*|-timeout=*|-parallel=*|-skip=*)
                test_args+=("-test.${arg#-}")
                ;;
            -v|-short|-failfast|-v=*|-short=*|-failfast=*)
                test_args+=("-test.${arg#-}")
                ;;
            -test.*|-docker)
                test_args+=("$arg")
                ;;
            *)
                # Keep Go's flag handling for less common test and build options.
                go test --docker -timeout 10m "${original_args[@]}"
                return $?
                ;;
        esac
    done
    /usr/local/bin/hw3test "${test_args[@]}"
}

validate_score_file() {
    score_lines="$(grep -c '^SCORE:' "$1" || true)"
    valid_score_lines="$(grep -Ec '^SCORE: [0-9]+([.][0-9]{1,2})?$' "$1" || true)"
    [ "$score_lines" -eq 1 ] && [ "$valid_score_lines" -eq 1 ] \
        || fatal "test command must report exactly one valid SCORE line"
}

configure_registry_proxy() {
    proxy_url="${DISTSYS_REGISTRY_PROXY_URL:-}"
    ca_file="/run/distsys-registry-proxy/ca.crt"

    [ -n "$proxy_url" ] || return 1
    printf '%s' "$proxy_url" | grep -Eq '^http://[A-Za-z0-9.-]+(:[0-9]+)?$' || {
        printf 'warning: invalid registry proxy URL; using direct Docker pulls\n' >&2
        return 1
    }
    [ -f "$ca_file" ] && [ ! -L "$ca_file" ] || {
        printf 'warning: registry proxy CA is unavailable; using direct Docker pulls\n' >&2
        return 1
    }

    downloaded_ca="$(mktemp)" || return 1
    if ! wget -q -T 5 -O "$downloaded_ca" "${proxy_url}/ca.crt" \
        || ! cmp -s "$ca_file" "$downloaded_ca"; then
        rm -f "$downloaded_ca"
        printf 'warning: registry proxy is unavailable or its CA differs; using direct Docker pulls\n' >&2
        return 1
    fi
    rm -f "$downloaded_ca"

    cp "$ca_file" /usr/local/share/ca-certificates/distsys-registry-proxy.crt
    update-ca-certificates >/dev/null
    proxy_no_proxy='localhost,127.0.0.1,::1,10.0.0.0/8,172.16.0.0/12,192.168.0.0/16'
    export HTTP_PROXY="$proxy_url" HTTPS_PROXY="$proxy_url" NO_PROXY="$proxy_no_proxy"
    export http_proxy="$proxy_url" https_proxy="$proxy_url" no_proxy="$proxy_no_proxy"
}

configure_registry_proxy || unset HTTP_PROXY HTTPS_PROXY NO_PROXY http_proxy https_proxy no_proxy

if [ "${HW3_REQUIRE_ZRAM:-0}" = 1 ]; then
    /usr/local/bin/verify-zram-scratch.sh || fatal "HW3_REQUIRE_ZRAM=1 but /hw/tests/tmp is not mounted from a zram ext4 device"
fi

# Start docker daemon
trap cleanup EXIT
dockerd-entrypoint.sh --storage-driver=overlay2 >/var/log/dockerd-entrypoint.log 2>&1 &
if ! wait_for_docker; then
    tail -n 200 /var/log/dockerd-entrypoint.log >&2 || true
    fatal "inner Docker daemon did not become ready"
fi

# Build server image
docker build solution -t hw3img || fatal "could not build solution image"

# Run tests
cd tests
export NO_COLOR=1
test_status=0
run_tests "$@" 2>&1 | tee tests.log || test_status=$?
validate_score_file tests.log

# Go reports a non-zero status when some grading groups fail. A valid score is
# the grading result; absence of a score remains an infrastructure failure.
if [ "$test_status" -ne 0 ]; then
    printf 'harness: grading tests exited with status %s after reporting a score\n' \
        "$test_status" >&2
fi