<?php
/**
 * ajax/containers.php
 *
 * Backs the Containers panel (and the container rows nested inside the
 * Pods panel — see ajax/pods.php). All actions go through PodmanClient,
 * i.e. the real libpod REST API over podman.sock; nothing here shells out.
 *
 * Actions (?action=...):
 *   list      GET  -> normalized array of containers for the table view
 *   inspect   GET  (&id=...) -> raw inspect JSON, for a detail dialog
 *   start     POST {"id": "..."}
 *   stop      POST {"id": "...", "timeout": 10}
 *   restart   POST {"id": "...", "timeout": 10}
 *   remove    POST {"id": "...", "force": false}
 *   pause     POST {"id": "..."}
 *   unpause   POST {"id": "..."}
 *   kill      POST {"id": "...", "signal": "SIGKILL"}
 *   rename    POST {"id": "...", "name": "..."}
 *   logs      GET  (&id=...&tail=200) -> plain text
 *   list_gpus GET  -> detected AMD/Intel GPUs (/dev/dri), for the Create Container form's optional passthrough toggle
 *   check_updates GET -> {"<image ref>": {"updateAvailable": bool, "error": "..."?}} for every image currently in use
 *   create    POST {"image": "...", "name": "...", "networkMode": "bridge"|"host"|"none"|"<custom-network-name>",
 *                    "staticIp": "10.1.1.222" (only meaningful with a custom/macvlan networkMode),
 *                    "ports": [{"hostPort": 8080, "containerPort": 80, "protocol": "tcp"}],
 *                    "volumes": [{"kind": "named"|"path", "source": "myvol"|"/mnt/...", "containerPath": "/data"}],
 *                    "env": [{"key": "...", "value": "..."}], "restartPolicy": "no", "pod": "<existing-pod-name>",
 *                    "gpuDevices": ["/dev/dri/renderD128", "/dev/dri/card0"],
 *                    "privileged": false, "startAfterCreate": true}
 */

declare(strict_types=1);

require __DIR__ . '/../include/bootstrap.php';

$action = $_GET['action'] ?? '';

switch ($action) {
    case 'list':
        podman_json_response(containers_list($client));
        break;

    case 'inspect':
        $id = (string) ($_GET['id'] ?? '');
        if ($id === '') {
            podman_json_error('Missing id', 400);
        }
        podman_json_response($client->inspectContainer($id));
        break;

    case 'logs':
        $id = (string) ($_GET['id'] ?? '');
        if ($id === '') {
            podman_json_error('Missing id', 400);
        }
        $tail = (int) ($_GET['tail'] ?? 200);
        podman_json_response(['text' => $client->containerLogs($id, $tail)]);
        break;

    case 'start':
        $body = podman_read_json_body();
        $client->startContainer(require_id($body));
        podman_json_response(['status' => 'started']);
        break;

    case 'stop':
        $body = podman_read_json_body();
        $client->stopContainer(require_id($body), (int) ($body['timeout'] ?? $podmanConfig->stopTimeoutSeconds));
        podman_json_response(['status' => 'stopped']);
        break;

    case 'restart':
        $body = podman_read_json_body();
        $client->restartContainer(require_id($body), (int) ($body['timeout'] ?? $podmanConfig->stopTimeoutSeconds));
        podman_json_response(['status' => 'restarted']);
        break;

    case 'remove':
        $body = podman_read_json_body();
        $client->removeContainer(require_id($body), (bool) ($body['force'] ?? false));
        podman_json_response(['status' => 'removed']);
        break;

    case 'pause':
        $body = podman_read_json_body();
        $client->pauseContainer(require_id($body));
        podman_json_response(['status' => 'paused']);
        break;

    case 'unpause':
        $body = podman_read_json_body();
        $client->unpauseContainer(require_id($body));
        podman_json_response(['status' => 'unpaused']);
        break;

    case 'kill':
        $body = podman_read_json_body();
        $client->killContainer(require_id($body), (string) ($body['signal'] ?? 'SIGKILL'));
        podman_json_response(['status' => 'killed']);
        break;

    case 'rename':
        $body = podman_read_json_body();
        $newName = trim((string) ($body['name'] ?? ''));
        if ($newName === '') {
            podman_json_error('Missing name in request body', 400);
        }
        $client->renameContainer(require_id($body), $newName);
        podman_json_response(['status' => 'renamed']);
        break;

    case 'list_gpus':
        podman_json_response(gpu_list());
        break;

    case 'check_updates':
        podman_json_response(check_image_updates($client));
        break;

    case 'create':
        $body = podman_read_json_body();
        $image = trim((string) ($body['image'] ?? ''));
        if ($image === '') {
            podman_json_error('Missing image in request body', 400);
        }
        $spec = build_container_spec($image, $body);
        // Unlike `podman run`, /containers/create does NOT auto-pull a
        // missing image — it fails outright with a 404 "no such image"
        // (found by live-testing the Create Container form against a
        // freshly-typed image reference that wasn't pulled yet). Retry
        // once after an explicit pull rather than always pulling
        // up-front, so re-creating with an image the user already has
        // stays fast and offline-friendly.
        try {
            $id = $client->createContainer($spec);
        } catch (PodmanApiException $e) {
            if ($e->httpStatus !== 404) {
                throw $e;
            }
            $client->pullImage($image);
            $id = $client->createContainer($spec);
        }
        if ($body['startAfterCreate'] ?? true) {
            $client->startContainer($id);
        }
        podman_json_response(['id' => $id, 'status' => ($body['startAfterCreate'] ?? true) ? 'started' : 'created']);
        break;

    default:
        podman_json_error("Unknown action '{$action}'", 400);
}

/**
 * Checks every image currently backing a (non-infra) container against its
 * origin registry — see RegistryClient for how, and why this isn't a
 * podman/libpod feature at all. Deduplicated per unique image reference
 * first (several containers commonly share the same image), so a host
 * with e.g. five containers all on the same base image only makes one
 * real registry request for it, not five.
 *
 * @return array<string,array<string,mixed>> keyed by image reference
 */
function check_image_updates(PodmanClient $client): array
{
    $digestByImageId = [];
    foreach ($client->listImages() as $img) {
        $digestByImageId[(string) ($img['Id'] ?? '')] = (string) ($img['Digest'] ?? '');
    }

    $localDigestByRef = [];
    foreach ($client->listContainers(true) as $c) {
        if ($c['IsInfra'] ?? false) {
            continue;
        }
        $ref = (string) ($c['Image'] ?? '');
        $imageId = (string) ($c['ImageID'] ?? '');
        if ($ref === '' || !isset($digestByImageId[$imageId])) {
            continue;
        }
        $localDigestByRef[$ref] = $digestByImageId[$imageId];
    }

    $out = [];
    foreach ($localDigestByRef as $ref => $localDigest) {
        $out[$ref] = $localDigest === ''
            ? ['error' => 'No local digest recorded for this image.']
            : RegistryClient::checkForUpdate($ref, $localDigest);
    }
    return $out;
}

/**
 * Detects AMD/Intel GPUs via /dev/dri + sysfs — NOT via any podman/libpod
 * API (libpod has no GPU inventory endpoint; this is plain host hardware
 * detection). NVIDIA is deliberately excluded: it needs the separate
 * nvidia-container-toolkit runtime, not a plain /dev/dri device passthrough,
 * so listing it here would offer a checkbox that doesn't actually work.
 * Verified live: card/render pairs from the same GPU share a "device"
 * symlink target under /sys/class/drm, which is how they're grouped below;
 * vendor 0x1002 = AMD, 0x8086 = Intel (PCI SIG IDs).
 *
 * @return array<int,array<string,mixed>>
 */
function gpu_list(): array
{
    if (!is_dir('/sys/class/drm')) {
        return [];
    }

    $byDevice = [];
    foreach (scandir('/sys/class/drm') ?: [] as $entry) {
        if (!preg_match('/^(card\d+|renderD\d+)$/', $entry)) {
            continue;
        }
        $devicePath = "/sys/class/drm/{$entry}/device";
        $target = @readlink($devicePath);
        if ($target === false) {
            continue;
        }
        $vendorFile = "{$devicePath}/vendor";
        if (!is_file($vendorFile)) {
            continue;
        }
        $vendorId = trim((string) @file_get_contents($vendorFile));
        $byDevice[$target]['vendorId'] ??= $vendorId;
        $byDevice[$target][str_starts_with($entry, 'card') ? 'card' : 'render'] = "/dev/dri/{$entry}";
    }

    $vendorNames = ['0x1002' => 'AMD', '0x8086' => 'Intel', '0x10de' => 'NVIDIA'];
    $out = [];
    foreach ($byDevice as $group) {
        $vendorId = $group['vendorId'] ?? '';
        $vendorName = $vendorNames[$vendorId] ?? $vendorId;
        // NVIDIA needs the nvidia-container-toolkit runtime, not a plain
        // /dev/dri passthrough — excluded so the checkbox we offer always
        // actually works (see function comment).
        if ($vendorName === 'NVIDIA' || !isset($group['render'])) {
            continue;
        }
        $out[] = [
            'vendor' => $vendorName,
            'card' => $group['card'] ?? null,
            'render' => $group['render'],
        ];
    }
    return $out;
}

/**
 * Builds a libpod SpecGenerator body (POST /containers/create) from the
 * WebUI's Create Container form fields. Field names/shapes here
 * (portmappings, netns, networks, mounts, volumes, restart_policy) were
 * verified live against a real podman system service — see
 * PodmanClient::createContainer()'s header comment.
 *
 * @param array<string,mixed> $body
 * @return array<string,mixed>
 */
function build_container_spec(string $image, array $body): array
{
    $spec = ['image' => $image];

    $name = trim((string) ($body['name'] ?? ''));
    if ($name !== '') {
        // Same character set podman itself enforces (define.NameRegex in
        // libpod) — validated here too so a space/invalid character gets
        // a clear message instead of podman's raw "running container
        // create option: names must match ...: invalid argument" (found
        // live: a template-derived container name with a space in it hit
        // exactly this).
        if (preg_match('/^[a-zA-Z0-9][a-zA-Z0-9_.-]*$/', $name) !== 1) {
            podman_json_error(
                "Container name (\"{$name}\") can only contain letters, digits, \".\", \"_\", \"-\" — no spaces. Try \"" .
                preg_replace('/[^a-zA-Z0-9_.-]+/', '-', $name) . '" instead.',
                400
            );
        }
        $spec['name'] = $name;
    }

    $env = [];
    foreach (($body['env'] ?? []) as $row) {
        $key = trim((string) ($row['key'] ?? ''));
        if ($key !== '') {
            $env[$key] = (string) ($row['value'] ?? '');
        }
    }
    if ($env !== []) {
        $spec['env'] = $env;
    }

    $ports = [];
    foreach (($body['ports'] ?? []) as $row) {
        $hostPort = (int) ($row['hostPort'] ?? 0);
        $containerPort = (int) ($row['containerPort'] ?? 0);
        if ($hostPort > 0 && $containerPort > 0) {
            $ports[] = [
                'host_ip' => '',
                'host_port' => $hostPort,
                'container_port' => $containerPort,
                'protocol' => (string) ($row['protocol'] ?? 'tcp'),
            ];
        }
    }
    if ($ports !== []) {
        $spec['portmappings'] = $ports;
    }

    $mounts = [];
    $volumes = [];
    foreach (($body['volumes'] ?? []) as $row) {
        $source = trim((string) ($row['source'] ?? ''));
        $containerPath = trim((string) ($row['containerPath'] ?? ''));
        if ($source === '' || $containerPath === '') {
            continue;
        }
        if (($row['kind'] ?? 'named') === 'path') {
            $mounts[] = ['destination' => $containerPath, 'type' => 'bind', 'source' => $source, 'options' => ['rbind']];
        } else {
            $volumes[] = ['name' => $source, 'dest' => $containerPath];
        }
    }
    if ($mounts !== []) {
        $spec['mounts'] = $mounts;
    }
    if ($volumes !== []) {
        $spec['volumes'] = $volumes;
    }

    // "bridge"/"host"/"none" are podman's own reserved netns modes; any
    // other value is an existing custom podman network's name, attached
    // via the "networks" field instead (verified live: passing a
    // network name through "networks" attaches it without needing an
    // explicit netns mode at all).
    $networkMode = (string) ($body['networkMode'] ?? 'bridge');
    if (in_array($networkMode, ['bridge', 'host', 'none'], true)) {
        $spec['netns'] = ['nsmode' => $networkMode];
    } elseif ($networkMode !== '') {
        // A static IP only makes sense on a custom (typically macvlan)
        // network — verified live that "networks":{"<name>":{"static_ips":
        // [...]}} assigns it, same as podman itself does for --ip. Basic
        // IPv4-shape validation only (not full RFC-correctness) — this
        // goes straight into a create request against the local podman
        // socket, not anywhere it could reach untrusted input otherwise.
        $staticIp = trim((string) ($body['staticIp'] ?? ''));
        if ($staticIp !== '') {
            if (preg_match('/^(\d{1,3}\.){3}\d{1,3}$/', $staticIp) !== 1) {
                podman_json_error("Static IP (\"{$staticIp}\") doesn't look like a valid IPv4 address.", 400);
            }
            $spec['networks'] = [$networkMode => ['static_ips' => [$staticIp]]];
        } else {
            $spec['networks'] = [$networkMode => new \stdClass()];
        }
    }

    if (isset($body['restartPolicy']) && $body['restartPolicy'] !== '') {
        $spec['restart_policy'] = (string) $body['restartPolicy'];
    }
    if ($body['privileged'] ?? false) {
        $spec['privileged'] = true;
    }

    $devices = [];
    foreach (($body['gpuDevices'] ?? []) as $path) {
        // Only ever pass through paths matching the exact shape gpu_list()
        // itself reports — the client only ever gets those as checkbox
        // values, but this is the boundary where a tampered/malicious
        // request body gets rejected rather than handing arbitrary host
        // device paths (e.g. "/dev/sda") straight into the container spec.
        if (is_string($path) && preg_match('#^/dev/dri/(card|renderD)\d+$#', $path) === 1) {
            $devices[] = ['path' => $path];
        }
    }
    if ($devices !== []) {
        $spec['devices'] = $devices;
    }

    $pod = trim((string) ($body['pod'] ?? ''));
    if ($pod !== '') {
        // "pod" joins an existing pod's shared network namespace — verified
        // live that it can be sent alongside "netns" above without
        // conflict (podman just defers to the pod's namespace).
        $spec['pod'] = $pod;
    }

    return $spec;
}

/** @param array<string,mixed> $body */
function require_id(array $body): string
{
    $id = (string) ($body['id'] ?? '');
    if ($id === '') {
        podman_json_error('Missing id in request body', 400);
    }
    return $id;
}

/**
 * Normalizes libpod's /containers/json entries into exactly what the
 * Containers table (javascript/containers.js) renders — keeping this
 * shaping logic server-side means the frontend never has to know libpod's
 * raw field names/quirks (e.g. Names is an array, State vs Status, etc).
 *
 * @return array<int,array<string,mixed>>
 */
function containers_list(PodmanClient $client): array
{
    $raw = $client->listContainers(true);
    $out = [];

    foreach ($raw as $c) {
        // Every pod has a hidden "infra" container managing its shared
        // network namespace — not something a user creates or can
        // meaningfully stop/remove on its own (found live: it always
        // shows "running" with no independent lifecycle, so Containers
        // panel gets a permanently un-removable row once any pod exists;
        // it already appears as its own row in the Pods panel). See
        // ajax/pods.php for actual pod lifecycle management.
        if ($c['IsInfra'] ?? false) {
            continue;
        }

        $names = $c['Names'] ?? [];
        $name = is_array($names) && count($names) > 0 ? ltrim((string) $names[0], '/') : podman_short_id((string) ($c['Id'] ?? ''));

        $ports = [];
        foreach (($c['Ports'] ?? []) as $p) {
            if (isset($p['host_port'], $p['container_port'])) {
                $ports[] = "{$p['host_port']}:{$p['container_port']}/" . ($p['protocol'] ?? 'tcp');
            } elseif (isset($p['container_port'])) {
                $ports[] = "{$p['container_port']}/" . ($p['protocol'] ?? 'tcp');
            }
        }

        $startedAt = podman_parse_time($c['StartedAt'] ?? null);
        $state = strtolower((string) ($c['State'] ?? 'unknown'));

        // One extra local-socket round trip per running container (~15ms
        // each, verified live — negligible for a home host's container
        // count). Best-effort: a container that stops between the list
        // call above and this one shouldn't blank out the whole table.
        $cpuPercent = null;
        $memUsageBytes = null;
        $memLimitBytes = null;
        if ($state === 'running') {
            try {
                $stats = $client->containerStats((string) ($c['Id'] ?? ''));
                $cpuPercent = isset($stats['cpu_stats']['cpu']) ? round((float) $stats['cpu_stats']['cpu'], 1) : null;
                $memUsageBytes = isset($stats['memory_stats']['usage']) ? (int) $stats['memory_stats']['usage'] : null;
                $memLimitBytes = isset($stats['memory_stats']['limit']) ? (int) $stats['memory_stats']['limit'] : null;
            } catch (PodmanApiException $e) {
                // leave stats null
            }
        }

        $out[] = [
            'id' => (string) ($c['Id'] ?? ''),
            'shortId' => podman_short_id((string) ($c['Id'] ?? '')),
            'name' => $name,
            'image' => (string) ($c['Image'] ?? ''),
            'state' => $state,
            'status' => (string) ($c['Status'] ?? ''),
            'health' => $c['Health']['Status'] ?? null,
            'ports' => $ports,
            'pod' => $c['Pod'] ?? null,
            'podName' => $c['PodName'] ?? null,
            'uptimeSeconds' => ($state === 'running' && $startedAt !== null) ? (time() - $startedAt) : null,
            'createdAt' => podman_parse_time($c['Created'] ?? null),
            'cpuPercent' => $cpuPercent,
            'memUsageBytes' => $memUsageBytes,
            'memLimitBytes' => $memLimitBytes,
        ];
    }

    usort($out, static fn($a, $b) => strcmp($a['name'], $b['name']));
    return $out;
}