<?php

namespace Modules\EcommerceFinance\Services;

use InvalidArgumentException;

/**
 * 统一解析上游数据源定义，避免业务代码直接拼接配置路径。
 */
class UpstreamSourceRegistry
{
    public function __construct(
        private readonly UpstreamStoredConfiguration $storedConfiguration,
    ) {
    }

    /**
     * @return array{key:string,label:string,config:string}
     */
    public function definition(string $source): array
    {
        $source = strtolower(trim($source));

        if ($source === '' || ! preg_match('/^[a-z0-9_-]+$/', $source)) {
            throw new InvalidArgumentException('上游数据源标识不合法。');
        }

        $definition = config('upstreams.sources.' . $source);

        if (! is_array($definition)) {
            $connection = $this->storedConfiguration->find($source);
            if ($connection === null) {
                throw new InvalidArgumentException('未登记的上游数据源：' . $source);
            }
            $definition = ['label' => $connection->name, 'config' => 'upstream_pipeline.defaults'];
        }

        $configKey = trim((string) ($definition['config'] ?? ''));

        if ($configKey === '' || ! preg_match('/^[a-z0-9_.-]+$/i', $configKey)) {
            throw new InvalidArgumentException('上游数据源配置路径不合法：' . $source);
        }

        return [
            'key' => $source,
            'label' => trim((string) ($definition['label'] ?? $source)) ?: $source,
            'config' => $configKey,
        ];
    }

    public function value(string $source, string $path, mixed $default = null): mixed
    {
        $definition = $this->definition($source);
        $suffix = trim($path, '.');
        $key = $definition['config'] . ($suffix === '' ? '' : '.' . $suffix);
        $configured = config($key, $default);

        if ($this->usesLocalConfiguration()) {
            return $configured;
        }

        if ($suffix === 'connection') {
            return $this->connection($definition['key'], (array) $configured);
        }

        if (str_starts_with($suffix, 'connection.')) {
            $field = substr($suffix, strlen('connection.'));
            $connection = $this->connection(
                $definition['key'],
                (array) config($definition['config'] . '.connection', []),
            );

            return $connection[$field] ?? $default;
        }

        return $this->storedConfiguration->value($definition['key'], $suffix, $configured);
    }

    public function enabled(string $source): bool
    {
        return (bool) $this->value($source, 'enabled', false);
    }

    public function driver(string $source): string
    {
        $definition = $this->definition($source);
        $default = config($definition['config'] . '.connection.driver', 'sqlsrv');
        return (string) (($this->usesLocalConfiguration()
            ? $default : $this->storedConfiguration->value($source, 'connection.driver', $default)) ?: 'sqlsrv');
    }

    /** @return array<string,array> */
    public function all(): array
    {
        $keys = array_unique(array_merge(array_keys((array) config('upstreams.sources', [])), array_keys($this->storedConfiguration->all())));
        $definitions = [];
        foreach ($keys as $key) {
            $definitions[$key] = $this->definition($key);
        }
        return $definitions;
    }

    private function usesLocalConfiguration(): bool
    {
        return (bool) config('upstreams.local_configuration.enabled', false);
    }

    private function connection(string $source, array $configured): array
    {
        $fields = array_values(array_unique(array_merge(array_keys($configured), [
            'driver',
            'host',
            'port',
            'database',
            'username',
            'password',
            'odbc_driver',
            'tds_version',
            'connect_timeout',
            'query_timeout',
        ])));
        $resolved = $configured;

        foreach ($fields as $field) {
            // ODBC 驱动由运行应用的操作系统决定，不能因共享记录中的
            // Windows 驱动名而覆盖 Linux 容器中的可用驱动。
            if ($field === 'odbc_driver' && trim((string) ($configured[$field] ?? '')) !== '') {
                $resolved[$field] = $configured[$field];

                continue;
            }

            $resolved[$field] = $this->storedConfiguration->value(
                $source,
                'connection.' . $field,
                $configured[$field] ?? null,
            );
        }

        return $this->withProductionTunnelEndpoint($source, $resolved);
    }

    /**
     * 生产服务器无法直连上游时，只覆盖到受限 SSH 隧道的私有端点。
     * 共享系统数据库仍是账号、密码和业务库信息的唯一来源，开发机则
     * 保持原始上游地址直连，避免把生产 Docker 网络地址传播给开发环境。
     */
    private function withProductionTunnelEndpoint(string $source, array $connection): array
    {
        if (
            ! app()->environment('production')
            || $this->usesLocalConfiguration()
            || ! $this->storedConfiguration->enabled()
        ) {
            return $connection;
        }

        $endpoint = config('upstreams.tunnel_endpoints.' . $source, []);

        if (! is_array($endpoint)) {
            return $connection;
        }

        $host = trim((string) ($endpoint['host'] ?? ''));
        $port = $endpoint['port'] ?? null;

        if ($host === '' && ($port === null || $port === '')) {
            return $connection;
        }

        if (
            $host === ''
            || preg_match('/^[A-Za-z0-9._:-]+$/', $host) !== 1
            || filter_var($port, FILTER_VALIDATE_INT, ['options' => ['min_range' => 1, 'max_range' => 65535]]) === false
        ) {
            throw new \RuntimeException('生产上游隧道端点配置不完整。');
        }

        return array_replace($connection, [
            'host' => $host,
            'port' => (int) $port,
        ]);
    }
}