<?php
/**
 * ajax/templates.php
 *
 * Backs the Templates panel — reusable container configs, saved and
 * loaded as XML in the same schema Unraid's own Docker Manager uses for
 * its Community Applications templates (<Container version="2"> with
 * <Config Type="Port"|"Path"|"Variable"> entries). Deliberately the SAME
 * schema, not a podman-specific one of our own: it's the one users and
 * template authors already know, and it means a template exported here
 * carries over the fields (image, ports, paths, variables, icon,
 * category, overview) a Docker template would too, even though the two
 * ecosystems' XML isn't fully interchangeable (this plugin's Config
 * entries don't have every attribute dockerMan's does, e.g. no GPU/USB/
 * device passthrough yet — see docs/ARCHITECTURE.md section 18).
 *
 * Stored at $bootDir/templates/<name>.xml — same boot-persistence
 * reasoning as compose/autostart/networks (see ajax/compose.php).
 *
 * Actions (?action=...):
 *   list     GET  -> [{name, image, icon, category, overview}, ...]
 *   get      GET  (&name=...) -> full parsed config, for prefilling the
 *                   Create Container form ("Use template")
 *   export   GET  (&name=...) -> {xml: "<raw XML text>"} for download
 *   save     POST {"name": "...", "image": "...", "icon": "...", "category": "...",
 *                   "overview": "...", "networkMode": "...", "privileged": false,
 *                   "restartPolicy": "...", "ports": [...], "volumes": [...], "env": [...]}
 *   import   POST {"xml": "<raw XML text>"} -> parses + saves as a new template
 *   list_local    GET  -> [{file, name, image, icon}, ...] from Unraid's own
 *                   dockerMan template directories (real existing Docker
 *                   templates the user already has — see
 *                   local_dockerman_templates_list()), for a "browse local
 *                   templates" picker instead of copy-pasting XML by hand
 *   import_local  POST {"file": "gitea.xml"} -> imports one by filename
 *                   (validated against the same directories list_local
 *                   scanned, never an arbitrary path from the client)
 *   remove   POST {"name": "..."}
 */

declare(strict_types=1);

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

$templatesDir = $podmanConfig->bootDir . '/templates';
$action = $_GET['action'] ?? '';

switch ($action) {
    case 'list':
        podman_json_response(templates_list($templatesDir));
        break;

    case 'get':
        podman_json_response(template_read(require_template_path($templatesDir, (string) ($_GET['name'] ?? ''))));
        break;

    case 'export':
        $path = require_template_path($templatesDir, (string) ($_GET['name'] ?? ''));
        podman_json_response(['xml' => file_get_contents($path)]);
        break;

    case 'save':
        $body = podman_read_json_body();
        $name = trim((string) ($body['name'] ?? ''));
        if (!is_valid_template_name($name)) {
            podman_json_error('Template name must be non-empty and contain only letters, digits, "-", "_".', 400);
        }
        template_write($templatesDir, $name, $body);
        podman_json_response(['status' => 'saved', 'name' => $name]);
        break;

    case 'import':
        $body = podman_read_json_body();
        $xml = (string) ($body['xml'] ?? '');
        if (trim($xml) === '') {
            podman_json_error('Missing xml in request body', 400);
        }
        $name = template_import($templatesDir, $xml);
        podman_json_response(['status' => 'imported', 'name' => $name]);
        break;

    case 'list_local':
        podman_json_response(local_dockerman_templates_list());
        break;

    case 'import_local':
        $body = podman_read_json_body();
        $file = (string) ($body['file'] ?? '');
        $name = template_import($templatesDir, local_dockerman_template_read($file));
        podman_json_response(['status' => 'imported', 'name' => $name]);
        break;

    case 'remove':
        $body = podman_read_json_body();
        $path = require_template_path($templatesDir, (string) ($body['name'] ?? ''));
        unlink($path);
        podman_json_response(['status' => 'removed']);
        break;

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

/**
 * Template names become filenames — restricted to a fixed safe character
 * set BEFORE ever being used to build a filesystem path, the same
 * pattern ajax/compose.php's is_valid_project_name() uses for the same
 * reason.
 */
function is_valid_template_name(string $name): bool
{
    return $name !== '' && preg_match('/^[a-zA-Z0-9_-]+$/', $name) === 1;
}

function require_template_path(string $templatesDir, string $name): string
{
    if (!is_valid_template_name($name)) {
        podman_json_error('Invalid template name', 400);
    }
    $path = $templatesDir . '/' . $name . '.xml';
    if (!is_file($path)) {
        podman_json_error("Template '{$name}' not found", 404);
    }
    return $path;
}

/** @return array<int,array<string,mixed>> */
function templates_list(string $templatesDir): array
{
    if (!is_dir($templatesDir)) {
        return [];
    }
    $out = [];
    foreach (scandir($templatesDir) ?: [] as $entry) {
        if (!str_ends_with($entry, '.xml')) {
            continue;
        }
        $name = substr($entry, 0, -4);
        if (!is_valid_template_name($name)) {
            continue;
        }
        try {
            $parsed = template_read($templatesDir . '/' . $entry);
        } catch (\Throwable $e) {
            continue; // a hand-edited/corrupt file shouldn't break the whole list
        }
        $out[] = [
            'name' => $name,
            'image' => $parsed['image'],
            'icon' => $parsed['icon'],
            'category' => $parsed['category'],
            'overview' => $parsed['overview'],
        ];
    }
    usort($out, static fn($a, $b) => strcmp($a['name'], $b['name']));
    return $out;
}

/**
 * Parses one template XML file into the same shape
 * ajax/containers.php's build_container_spec() (Create Container form)
 * consumes, so "Use template" can feed straight into that form/action.
 *
 * @return array<string,mixed>
 */
function template_read(string $path): array
{
    $xml = @simplexml_load_file($path);
    if ($xml === false) {
        podman_json_error("Could not parse template XML: {$path}", 500);
    }

    $ports = [];
    $volumes = [];
    $env = [];
    foreach ($xml->Config as $cfg) {
        $attrs = $cfg->attributes();
        $type = (string) ($attrs['Type'] ?? '');
        $value = trim((string) $cfg);
        $target = (string) ($attrs['Target'] ?? '');
        if ($value === '') {
            continue;
        }
        switch ($type) {
            case 'Port':
                $ports[] = [
                    'hostPort' => (int) $value,
                    'containerPort' => (int) ($target !== '' ? $target : $value),
                    'protocol' => (string) ($attrs['Mode'] ?? 'tcp') ?: 'tcp',
                ];
                break;
            case 'Path':
                $volumes[] = [
                    'kind' => 'path',
                    'source' => $value,
                    'containerPath' => $target !== '' ? $target : $value,
                ];
                break;
            case 'Variable':
                $env[] = ['key' => $target !== '' ? $target : (string) ($attrs['Name'] ?? ''), 'value' => $value];
                break;
        }
    }

    return [
        'image' => (string) $xml->Repository,
        'networkMode' => (string) ($xml->Network ?: 'bridge'),
        'privileged' => strtolower((string) $xml->Privileged) === 'true',
        'icon' => (string) $xml->Icon,
        'category' => (string) $xml->Category,
        'overview' => (string) $xml->Overview,
        'ports' => $ports,
        'volumes' => $volumes,
        'env' => $env,
    ];
}

/**
 * Writes a template XML file from the Create Container form's field
 * shapes (same as build_container_spec() in ajax/containers.php takes)
 * plus template-only metadata (icon/category/overview). Uses DOMDocument
 * rather than string concatenation so every value is properly escaped —
 * no risk of a "<" or "&" in an image name/description breaking the XML.
 *
 * @param array<string,mixed> $body
 */
function template_write(string $templatesDir, string $name, array $body): void
{
    if (!is_dir($templatesDir) && !mkdir($templatesDir, 0755, true) && !is_dir($templatesDir)) {
        podman_json_error("Could not create {$templatesDir}", 500);
    }

    $doc = new \DOMDocument('1.0');
    $doc->formatOutput = true;
    $root = $doc->createElement('Container');
    $root->setAttribute('version', '2');
    $doc->appendChild($root);

    $append = static function (string $tag, string $value) use ($doc, $root): void {
        $root->appendChild($doc->createElement($tag, $value));
    };
    $append('Name', $name);
    $append('Repository', trim((string) ($body['image'] ?? '')));
    $append('Network', (string) ($body['networkMode'] ?? 'bridge'));
    $append('Privileged', ($body['privileged'] ?? false) ? 'true' : 'false');
    $append('Overview', (string) ($body['overview'] ?? ''));
    $append('Category', (string) ($body['category'] ?? ''));
    $append('Icon', (string) ($body['icon'] ?? ''));

    foreach (($body['ports'] ?? []) as $row) {
        $hostPort = (string) ($row['hostPort'] ?? '');
        $containerPort = (string) ($row['containerPort'] ?? '');
        if ($hostPort === '' || $containerPort === '') {
            continue;
        }
        $cfg = $doc->createElement('Config', $hostPort);
        $cfg->setAttribute('Name', 'Port ' . $containerPort);
        $cfg->setAttribute('Target', $containerPort);
        $cfg->setAttribute('Mode', (string) ($row['protocol'] ?? 'tcp'));
        $cfg->setAttribute('Type', 'Port');
        $root->appendChild($cfg);
    }
    foreach (($body['volumes'] ?? []) as $row) {
        $source = (string) ($row['source'] ?? '');
        $containerPath = (string) ($row['containerPath'] ?? '');
        if ($source === '' || $containerPath === '' || ($row['kind'] ?? 'named') !== 'path') {
            continue; // named (podman-managed) volumes aren't portable across hosts, so templates only capture host-path binds
        }
        $cfg = $doc->createElement('Config', $source);
        $cfg->setAttribute('Name', basename($containerPath));
        $cfg->setAttribute('Target', $containerPath);
        $cfg->setAttribute('Mode', 'rw');
        $cfg->setAttribute('Type', 'Path');
        $root->appendChild($cfg);
    }
    foreach (($body['env'] ?? []) as $row) {
        $key = (string) ($row['key'] ?? '');
        if ($key === '') {
            continue;
        }
        $cfg = $doc->createElement('Config', (string) ($row['value'] ?? ''));
        $cfg->setAttribute('Name', $key);
        $cfg->setAttribute('Target', $key);
        $cfg->setAttribute('Type', 'Variable');
        $root->appendChild($cfg);
    }

    if ($doc->save($templatesDir . '/' . $name . '.xml') === false) {
        podman_json_error("Could not write {$templatesDir}/{$name}.xml", 500);
    }
}

/**
 * Imports a pasted/uploaded template XML (this plugin's own schema, or
 * a plain Unraid dockerMan template — both use the same <Container>/
 * <Config> shape). Validates it parses and has a usable <Name> before
 * writing it under our own templates dir with a sanitized filename.
 */
function template_import(string $templatesDir, string $xmlText): string
{
    $xml = @simplexml_load_string($xmlText);
    if ($xml === false || $xml->getName() !== 'Container') {
        podman_json_error('Not a valid template XML (expected a <Container> root element)', 400);
    }

    $rawName = trim((string) $xml->Name);
    $name = preg_replace('/[^a-zA-Z0-9_-]/', '-', $rawName);
    if (!is_valid_template_name((string) $name)) {
        podman_json_error('Template XML has no usable <Name>', 400);
    }

    if (!is_dir($templatesDir) && !mkdir($templatesDir, 0755, true) && !is_dir($templatesDir)) {
        podman_json_error("Could not create {$templatesDir}", 500);
    }
    if (file_put_contents($templatesDir . '/' . $name . '.xml', $xmlText, LOCK_EX) === false) {
        podman_json_error("Could not write {$templatesDir}/{$name}.xml", 500);
    }
    return (string) $name;
}

/**
 * Unraid's own Docker Manager plugin stores every template a user has
 * ever saved/customized under templates-user/, plus a local cache of
 * Community Applications' own catalog under templates-community/ (may
 * be empty/absent if CA was never installed) — both in the same
 * <Container>/<Config> XML shape this plugin reads. Read-only: this
 * plugin never writes into dockerMan's own directories.
 *
 * @return array<int,string>
 */
function dockerman_template_dirs(): array
{
    return array_values(array_filter([
        '/boot/config/plugins/dockerMan/templates-user',
        '/boot/config/plugins/dockerMan/templates-community',
    ], 'is_dir'));
}

/** @return array<int,array<string,string>> */
function local_dockerman_templates_list(): array
{
    $out = [];
    foreach (dockerman_template_dirs() as $dir) {
        foreach (scandir($dir) ?: [] as $entry) {
            if (!str_ends_with($entry, '.xml')) {
                continue;
            }
            $xml = @simplexml_load_file($dir . '/' . $entry);
            if ($xml === false) {
                continue; // skip anything that doesn't parse rather than failing the whole list
            }
            $out[] = [
                'file' => $entry,
                'name' => (string) $xml->Name,
                'image' => (string) $xml->Repository,
                'icon' => (string) $xml->Icon,
            ];
        }
    }
    usort($out, static fn($a, $b) => strcmp($a['name'], $b['name']));
    return $out;
}

/**
 * Reads one local dockerMan template's raw XML by filename. $file comes
 * straight from client input — reduced to its basename and required to
 * actually exist in one of dockerman_template_dirs() (the same list
 * list_local scanned), never treated as an arbitrary path.
 */
function local_dockerman_template_read(string $file): string
{
    $file = basename($file);
    if (!str_ends_with($file, '.xml')) {
        podman_json_error('Invalid template file', 400);
    }
    foreach (dockerman_template_dirs() as $dir) {
        $path = $dir . '/' . $file;
        if (is_file($path)) {
            $content = file_get_contents($path);
            if ($content !== false) {
                return $content;
            }
        }
    }
    podman_json_error("Local template '{$file}' not found", 404);
}