<?php

declare(strict_types=1);

namespace app\common\service\followupaudio;

/** Server-only provider identity. Changing any request identity invalidates the audio gate. */
final class FollowupAudioProviderConfig
{
    public static function resolve(string $profile, ?array $settings = null, ?array $legacy = null): array
    {
        if (!in_array($profile, ['qwen', 'openai'], true)) { throw new FollowupAudioException('INVALID_PROFILE'); }
        $settings = $settings ?? (array) config('followup_audio', []);
        $legacy = $legacy ?? (array) config('prescription_ai', []);
        $provider = (array) ($settings['providers'][$profile] ?? []);
        $driver = (string) ($provider['driver'] ?? 'dify');
        if (!in_array($driver, ['dify', 'openai_audio'], true)) { throw new FollowupAudioException('CONFIG_INVALID'); }
        $base = (string) ($provider['base_url'] ?? '');
        $key = (string) ($provider['api_key'] ?? '');
        if ($driver === 'dify') {
            if ($base === '') { $base = (string) ($legacy['base_url'] ?? ''); }
            if ($key === '') { $key = (string) ($legacy['models'][$profile]['api_key'] ?? ''); }
        }
        $model = (string) ($provider['model'] ?? '');
        $label = trim((string) ($provider['label'] ?? ''));
        if ($label === '') { $label = $model !== '' ? $model : $profile; }
        if ($base === '' || $key === '' || ($driver === 'openai_audio' && $model === '')) { throw new FollowupAudioException('CONFIG_MISSING'); }
        $parts = parse_url($base);
        if (!is_array($parts) || !in_array($parts['scheme'] ?? '', ['http', 'https'], true)
            || empty($parts['host']) || isset($parts['user']) || isset($parts['pass']) || isset($parts['query']) || isset($parts['fragment'])
            || preg_match('/[\x00-\x20\x7f\\\\]/', $base) || preg_match('/[\x00-\x20\x7f]/', $key)
            || strlen($model) > 200 || preg_match('/[\x00-\x20\x7f]/', $model)
            || trim($label) === '' || strlen($label) > 200 || preg_match('/[\x00-\x1f\x7f]/', $label)) {
            throw new FollowupAudioException('CONFIG_INVALID');
        }
        $base = rtrim($base, '/');
        $path = rtrim((string) ($parts['path'] ?? ''), '/');
        if ($driver === 'dify' && str_ends_with($path, '/chat/completions')) {
            throw new FollowupAudioException('DIFY_APPLICATION_REQUIRED');
        }
        if ($driver === 'openai_audio' && str_ends_with($path, '/chat-messages')) {
            throw new FollowupAudioException('CONFIG_INVALID');
        }
        $endpoint = $driver === 'dify' ? '/chat-messages' : '/chat/completions';
        if (str_ends_with($base, $endpoint)) { $base = substr($base, 0, -strlen($endpoint)); }
        elseif (!str_ends_with($base, '/v1')) { $base .= '/v1'; }
        $fingerprint = hash('sha256', json_encode([$driver, $base, $model, $key], JSON_UNESCAPED_SLASHES | JSON_THROW_ON_ERROR));
        return ['driver' => $driver, 'base_url' => $base, 'api_key' => $key, 'model' => $model, 'label' => $label, 'fingerprint' => $fingerprint];
    }

    /** No endpoint, model credential or plaintext provider data in capability responses. */
    public static function status(string $profile, ?array $settings = null, ?array $legacy = null): array
    {
        try {
            $provider = self::resolve($profile, $settings, $legacy);
            return ['configured' => true, 'profile' => $profile, 'code' => 'OK', 'application_fingerprint' => $provider['fingerprint']];
        } catch (FollowupAudioException $error) {
            return ['configured' => false, 'profile' => in_array($profile, ['qwen', 'openai'], true) ? $profile : 'invalid', 'code' => $error->errorCode];
        }
    }

    public static function isVerified(string $profile): bool
    {
        return self::verified($profile, (array) config('followup_audio', []), (array) config('prescription_ai', []));
    }

    /** Shared with injected-config transport tests; enabled remains an independent operational switch. */
    public static function verified(string $profile, array $settings, array $legacy): bool
    {
        if (empty($settings['audio_verified']) || !in_array($profile, (array) ($settings['verified_profiles'] ?? []), true)) { return false; }
        try { $provider = self::resolve($profile, $settings, $legacy); }
        catch (FollowupAudioException $error) { return false; }
        $verified = (string) ($settings['providers'][$profile]['verified_fingerprint'] ?? '');
        return str_starts_with($provider['base_url'], 'https://') && preg_match('/^[a-f0-9]{64}$/D', $verified)
            && hash_equals($provider['fingerprint'], $verified);
    }

    public static function publicModels(): array
    {
        $models = [];
        foreach (['qwen', 'openai'] as $profile) {
            if (self::isVerified($profile)) { $models[] = ['value' => $profile, 'label' => self::resolve($profile)['label']]; }
        }
        return $models;
    }
}