#!/usr/bin/env bash
set -euo pipefail

MODULE_NAME="${MODULE_NAME:-ngx_http_monitoring_module}"
BUILD_NGINX_VERSIONS="${BUILD_NGINX_VERSIONS:-}"
NEXT_VERSION="${NEXT_VERSION:-0.0.0}"
NEXT_TAG="${NEXT_TAG:-v${NEXT_VERSION}}"
LATEST_TAG="${LATEST_TAG:-none}"
TARGET_ARCH="${TARGET_ARCH:-$(uname -m)}"
DOCKER_PLATFORM="${DOCKER_PLATFORM:-unknown}"
RELEASE_BUILD_IMAGE="${RELEASE_BUILD_IMAGE:-unknown}"
RELEASE_LIBC_BASELINE="${RELEASE_LIBC_BASELINE:-unknown}"
NGINX_CONFIGURE_ARGS="${NGINX_CONFIGURE_ARGS:---with-compat --with-http_ssl_module --with-http_stub_status_module}"
DIST_DIR="${DIST_DIR:-/work/dist}"
WORK_ROOT="${WORK_ROOT:-/work/.release-work/upstream}"
VALIDATION_PORT="${VALIDATION_PORT:-18080}"
GITHUB_REF="${GITHUB_REF:-unknown}"
GITHUB_SHA="${GITHUB_SHA:-unknown}"

export DEBIAN_FRONTEND=noninteractive

fail() {
    echo "error: $*" >&2
    exit 1
}

slugify() {
    tr '[:upper:]' '[:lower:]' \
        | sed -E 's/[^a-z0-9.+~]+/./g; s/^[.]+//; s/[.]+$//'
}

validate_module() {
    local nginx_bin="$1"
    local module_path="$2"
    local runtime_root="$3"
    local config_path="$runtime_root/nginx.conf"
    local base_url="http://127.0.0.1:${VALIDATION_PORT}"
    local status
    local dashboard
    local sse_output

    rm -rf "$runtime_root"
    mkdir -p \
        "$runtime_root/logs" \
        "$runtime_root/temp/client_body" \
        "$runtime_root/temp/proxy" \
        "$runtime_root/temp/fastcgi" \
        "$runtime_root/temp/uwsgi" \
        "$runtime_root/temp/scgi"

    {
        printf 'load_module %s;\n\n' "$module_path"
        printf 'worker_processes 1;\n'
        printf 'error_log %s/logs/error.log info;\n' "$runtime_root"
        printf 'pid %s/logs/nginx.pid;\n\n' "$runtime_root"
        printf 'events {\n'
        printf '    worker_connections 1024;\n'
        printf '}\n\n'
        printf 'http {\n'
        printf '    access_log off;\n'
        printf '    default_type application/octet-stream;\n'
        printf '    client_body_temp_path %s/temp/client_body;\n' "$runtime_root"
        printf '    proxy_temp_path %s/temp/proxy;\n' "$runtime_root"
        printf '    fastcgi_temp_path %s/temp/fastcgi;\n' "$runtime_root"
        printf '    uwsgi_temp_path %s/temp/uwsgi;\n' "$runtime_root"
        printf '    scgi_temp_path %s/temp/scgi;\n\n' "$runtime_root"
        printf '    monitor_refresh_interval 1s;\n'
        printf '    monitor_history 1m;\n'
        printf '    monitor_resolution 1s;\n'
        printf '    monitor_shm_size 8m;\n'
        printf '    monitor_collect_system on;\n'
        printf '    monitor_collect_nginx on;\n'
        printf '    monitor_collect_network on;\n'
        printf '    monitor_access_log on;\n'
        printf '    monitor_max_top_urls 100;\n\n'
        printf '    server {\n'
        printf '        listen 127.0.0.1:%s;\n' "$VALIDATION_PORT"
        printf '        server_name localhost;\n\n'
        printf '        location /monitor {\n'
        printf '            monitor on;\n'
        printf '            monitor_dashboard on;\n'
        printf '            monitor_api on;\n'
        printf '            monitor_sse on;\n'
        printf '            monitor_allow all;\n'
        printf '            monitor_basic_auth off;\n'
        printf '            monitor_cors off;\n'
        printf '            monitor_rate_limit 120;\n'
        printf '        }\n\n'
        printf '        location / {\n'
        printf '            return 200 "ok\\n";\n'
        printf '        }\n'
        printf '    }\n'
        printf '}\n'
    } > "$config_path"

    "$nginx_bin" -t -p "$runtime_root" -c "$config_path"

    cleanup() {
        "$nginx_bin" -p "$runtime_root" -c "$config_path" -s quit >/dev/null 2>&1 || true
    }
    trap cleanup RETURN

    "$nginx_bin" -p "$runtime_root" -c "$config_path"

    for attempt in $(seq 1 50); do
        if curl -fsS "$base_url/" >/dev/null; then
            break
        fi

        if [[ "$attempt" -eq 50 ]]; then
            echo "Nginx did not become ready" >&2
            return 1
        fi

        sleep 0.2
    done

    curl -fsS "$base_url/" | grep -q '^ok'

    status="$(curl -fsS -o "$runtime_root/dashboard.html" -w '%{http_code}' "$base_url/monitor")"
    [[ "$status" == "200" ]] || fail "/monitor returned HTTP $status"
    dashboard="$(cat "$runtime_root/dashboard.html")"
    printf '%s' "$dashboard" | grep -q '<title>Nginx Monitor</title>'
    printf '%s' "$dashboard" | grep -q '/monitor/api'
    printf '%s' "$dashboard" | grep -q '/monitor/live'

    curl -fsS "$base_url/monitor/api" \
        | jq -e '.version == 1 and has("system") and has("nginx") and has("requests") and has("history")' >/dev/null
    curl -fsS "$base_url/monitor/api/system" \
        | jq -e '.version == 1 and .scope == "system" and has("system")' >/dev/null
    curl -fsS "$base_url/monitor/api/nginx" \
        | jq -e '.version == 1 and .scope == "nginx" and has("nginx")' >/dev/null
    curl -fsS "$base_url/monitor/health" \
        | jq -e '.version == 1 and .scope == "health" and .status == "ok"' >/dev/null
    curl -fsS "$base_url/monitor/metrics" \
        | grep -q '^nginx_monitor_requests_total '

    sse_output="$(timeout 5s curl -fsS -N "$base_url/monitor/live" || true)"
    printf '%s' "$sse_output" | grep -q '^event: metrics'
    printf '%s' "$sse_output" | grep -q '^data: {'

    cleanup
    trap - RETURN
}

[[ -n "$BUILD_NGINX_VERSIONS" ]] || fail "BUILD_NGINX_VERSIONS is required"

apt-get update
apt-get install -y --no-install-recommends \
    binutils \
    build-essential \
    ca-certificates \
    curl \
    file \
    jq \
    libpcre2-dev \
    libssl-dev \
    zlib1g-dev
rm -rf /var/lib/apt/lists/*

mkdir -p "$DIST_DIR" "$WORK_ROOT"

for nginx_version in $BUILD_NGINX_VERSIONS; do
    archive="nginx-${nginx_version}.tar.gz"
    archive_path="${WORK_ROOT}/${archive}"
    workdir="${WORK_ROOT}/nginx-${nginx_version}"
    runtime_root="${WORK_ROOT}/runtime/nginx-${nginx_version}"

    if [[ ! -f "$archive_path" ]]; then
        curl -fsSLo "$archive_path" "https://nginx.org/download/${archive}"
    fi

    rm -rf "$workdir"
    tar -xzf "$archive_path" -C "$WORK_ROOT"

    nginx_version_slug="$(printf '%s' "$nginx_version" | slugify)"
    build_metadata="$(printf 'nginxorg.%s.%s.%s' "$nginx_version_slug" "$TARGET_ARCH" "$RELEASE_LIBC_BASELINE" | slugify)"
    module_cflags="-DNGX_HTTP_MONITORING_MODULE_VERSION=\\\"${NEXT_VERSION}\\\" -DNGX_HTTP_MONITORING_BUILD_METADATA=\\\"${build_metadata}\\\""

    cd "$workdir"
    ./configure \
        --prefix=/usr/local/nginx \
        --sbin-path=/usr/local/sbin/nginx \
        --modules-path=/usr/local/nginx/modules \
        --conf-path=/etc/nginx/nginx.conf \
        --error-log-path=/var/log/nginx/error.log \
        --http-log-path=/var/log/nginx/access.log \
        --pid-path=/var/run/nginx.pid \
        --lock-path=/var/run/nginx.lock \
        --http-client-body-temp-path=/var/cache/nginx/client_temp \
        --http-proxy-temp-path=/var/cache/nginx/proxy_temp \
        --http-fastcgi-temp-path=/var/cache/nginx/fastcgi_temp \
        --http-uwsgi-temp-path=/var/cache/nginx/uwsgi_temp \
        --http-scgi-temp-path=/var/cache/nginx/scgi_temp \
        --with-cc-opt="$module_cflags" \
        $NGINX_CONFIGURE_ARGS \
        --add-dynamic-module=/work

    build_jobs="$(nproc)"
    if [[ "$TARGET_ARCH" != "linux-x86_64" && "$build_jobs" -gt 2 ]]; then
        build_jobs=2
    fi

    make -j"$build_jobs"
    make -j"$build_jobs" modules

    module_path="$workdir/objs/${MODULE_NAME}.so"
    nginx_bin="$workdir/objs/nginx"
    [[ -x "$nginx_bin" ]] || fail "nginx binary was not built at ${nginx_bin}"
    [[ -f "$module_path" ]] || fail "module was not built at ${module_path}"

    strip --strip-unneeded "$module_path" || true
    validate_module "$nginx_bin" "$module_path" "$runtime_root"

    module_sha256="$(sha256sum "$module_path" | awk '{ print $1 }')"
    archive_sha256="$(sha256sum "$archive_path" | awk '{ print $1 }')"
    artifact_base="${MODULE_NAME}-${NEXT_TAG}-nginxorg-${nginx_version_slug}-${TARGET_ARCH}"
    package_root="${WORK_ROOT}/packages/${artifact_base}"
    compatibility_json="${package_root}/COMPATIBILITY.json"

    rm -rf "$package_root"
    mkdir -p "$package_root/modules" "$package_root/docs" "$package_root/examples"

    cp "$module_path" "$package_root/modules/${MODULE_NAME}.so"
    cp /work/examples/nginx.conf "$package_root/examples/nginx.conf"
    cp /work/examples/monitoring-site.conf "$package_root/examples/monitoring-site.conf"
    cp /work/README.md "$package_root/README.md"
    cp /work/docs/API.md "$package_root/docs/API.md"
    cp /work/docs/CONFIGURATION.md "$package_root/docs/CONFIGURATION.md"
    cp /work/docs/PERFORMANCE.md "$package_root/docs/PERFORMANCE.md"
    "$nginx_bin" -V > "$package_root/NGINX-V.txt" 2>&1

    tarball_file="${artifact_base}.tar.gz"
    sidecar_file="${artifact_base}.compatibility.json"

    jq -n \
        --arg schema "1" \
        --arg module "$MODULE_NAME" \
        --arg releaseTag "$NEXT_TAG" \
        --arg releaseVersion "$NEXT_VERSION" \
        --arg previousTag "$LATEST_TAG" \
        --arg gitRef "$GITHUB_REF" \
        --arg gitSha "$GITHUB_SHA" \
        --arg buildImage "$RELEASE_BUILD_IMAGE" \
        --arg libcBaseline "$RELEASE_LIBC_BASELINE" \
        --arg dockerPlatform "$DOCKER_PLATFORM" \
        --arg targetArch "$TARGET_ARCH" \
        --arg nginxVersion "$nginx_version" \
        --arg configureArgs "$NGINX_CONFIGURE_ARGS" \
        --arg archive "$archive" \
        --arg archiveSha256 "$archive_sha256" \
        --arg moduleSha256 "$module_sha256" \
        --arg builtAt "$(date -u +%Y-%m-%dT%H:%M:%SZ)" \
        --arg artifactBase "$artifact_base" \
        --arg tarballFile "$tarball_file" \
        --arg sidecarFile "$sidecar_file" \
        --arg validationTime "$(date -u +%Y-%m-%dT%H:%M:%SZ)" \
        '{
            schema: ($schema | tonumber),
            module: $module,
            release: {
                tag: $releaseTag,
                version: $releaseVersion,
                previous_tag: $previousTag,
                git_ref: $gitRef,
                git_sha: $gitSha
            },
            target: {
                os_id: "nginx.org-source",
                os_version: $nginxVersion,
                os_codename: "upstream",
                architecture: $targetArch,
                requested_target: $targetArch,
                docker_image: $buildImage,
                docker_platform: $dockerPlatform,
                libc_baseline: $libcBaseline
            },
            nginx: {
                binary_package: "nginx.org-source-build",
                binary_version: $nginxVersion,
                source_package: "nginx.org",
                source_version: $nginxVersion,
                abi: "",
                modules_path: "/usr/local/nginx/modules",
                build: {
                    version: ("nginx/" + $nginxVersion),
                    configure_args: ($configureArgs | split(" ")),
                    configure_line: $configureArgs
                }
            },
            build: {
                method: "upstream-nginxorg-source",
                source_archive: $archive,
                source_archive_sha256: $archiveSha256,
                module_sha256: $moduleSha256,
                built_at: $builtAt
            },
            artifacts: {
                base_name: $artifactBase,
                deb_package: "",
                deb_version: "",
                deb_file: "",
                tarball_file: $tarballFile,
                compatibility_file: $sidecarFile
            },
            packaging: {
                deb_depends: []
            },
            validation: {
                packaged_nginx_config_test: false,
                packaged_nginx_endpoint_smoke: false,
                built_nginx_config_test: true,
                built_nginx_endpoint_smoke: true,
                validated_at: $validationTime
            }
        }' > "$compatibility_json"

    {
        printf '# %s for nginx.org %s\n\n' "$MODULE_NAME" "$nginx_version"
        printf 'Release: `%s`\n\n' "$NEXT_TAG"
        printf 'Target: `%s` (`%s`)\n\n' "$TARGET_ARCH" "$DOCKER_PLATFORM"
        printf 'Build baseline: `%s`\n\n' "$RELEASE_LIBC_BASELINE"
        printf 'This tarball is built against upstream nginx.org source, not a Debian or Ubuntu source package.\n\n'
        printf 'Use this artifact for Nginx binaries built from the same upstream source version and compatible configure options. For distribution-packaged Nginx, prefer the distro `.deb` release artifacts.\n\n'
        printf 'Load it near the top of `nginx.conf`:\n\n'
        printf '```nginx\n'
        printf 'load_module modules/%s.so;\n' "$MODULE_NAME"
        printf '```\n'
    } > "$package_root/INSTALL.md"

    {
        printf 'module=%s\n' "$MODULE_NAME"
        printf 'module_release=%s\n' "$NEXT_TAG"
        printf 'module_version=%s\n' "$NEXT_VERSION"
        printf 'module_build_metadata=%s\n' "$build_metadata"
        printf 'nginx_source=nginx.org\n'
        printf 'nginx_version=%s\n' "$nginx_version"
        printf 'target=%s\n' "$TARGET_ARCH"
        printf 'docker_platform=%s\n' "$DOCKER_PLATFORM"
        printf 'build_image=%s\n' "$RELEASE_BUILD_IMAGE"
        printf 'libc_baseline=%s\n' "$RELEASE_LIBC_BASELINE"
        printf 'configure_args=%s\n' "$NGINX_CONFIGURE_ARGS"
        printf 'git_ref=%s\n' "$GITHUB_REF"
        printf 'git_sha=%s\n' "$GITHUB_SHA"
        printf 'built_at=%s\n' "$(date -u +%Y-%m-%dT%H:%M:%SZ)"
    } > "$package_root/METADATA.txt"

    (
        cd "$package_root"
        sha256sum "modules/${MODULE_NAME}.so" COMPATIBILITY.json > SHA256SUMS
        file "modules/${MODULE_NAME}.so" > FILE.txt
    )

    tar -czf "$DIST_DIR/$tarball_file" -C "$(dirname "$package_root")" "$(basename "$package_root")"
    cp "$compatibility_json" "$DIST_DIR/$sidecar_file"

    echo "Built $DIST_DIR/$tarball_file"
    echo "Built $DIST_DIR/$sidecar_file"
done