<?php

namespace app\common\service\ai;

use app\common\model\ai\AiConfig;

class AiAssistantResponder
{
    public static function respond(AiAssistantTrace $trace): AiAssistantTrace
    {
        $messages = self::buildModelMessages($trace->historyMessages, $trace->originalMessage, $trace->plan, $trace->contextText);
        $result = self::callAssistantModel($messages);

        $trace->responseResult = $result;
        $trace->finalAnswer = !empty($result['success'])
            ? trim((string) ($result['content'] ?? ''))
            : 'AI助手暂时没有生成成功，请稍后再试。';

        if ($trace->finalAnswer === '') {
            $trace->finalAnswer = '我暂时没有找到足够的站内依据，请换个关键词再问一次。';
        }

        return $trace;
    }

    private static function buildModelMessages(array $history, string $message, array $plan, string $contextText): array
    {
        $messages = [
            [
                'role' => 'system',
                'content' => AiConfig::getVal('assistant_system_prompt', self::defaultSystemPrompt()),
            ],
        ];

        foreach ($history as $row) {
            $role = $row['role'] === 'assistant' ? 'assistant' : 'user';
            $content = trim((string) ($row['content'] ?? ''));
            if ($content !== '') {
                $messages[] = ['role' => $role, 'content' => mb_substr($content, 0, 1000)];
            }
        }

        $planSummary = json_encode([
            'intent' => $plan['intent'] ?? '',
            'rewritten_query' => $plan['rewritten_query'] ?? '',
            'alternate_queries' => $plan['alternate_queries'] ?? [],
            'domains' => $plan['domains'] ?? [],
            'preferred_domain' => $plan['preferred_domain'] ?? '',
            'entities' => $plan['entities'] ?? [],
            'date_range' => $plan['date_range'] ?? [],
            'needs_realtime' => $plan['needs_realtime'] ?? false,
            'confidence' => $plan['confidence'] ?? 0,
        ], JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT);

        $messages[] = [
            'role' => 'user',
            'content' => "用户问题：\n{$message}\n\n查询理解结果：\n"
                . $planSummary
                . "\n\n站内资料、联网资讯与实时上下文：\n"
                . ($contextText ?: '{}')
                . "\n\n请按照“直接结论、依据摘要、相关内容、风险提示”的结构回答。"
                . "如果站内资料不足，请明确说明，不要编造。彩票、赛事预测、加密行情必须提示不构成投资或购彩建议。",
        ];

        return $messages;
    }

    private static function callAssistantModel(array $messages): array
    {
        $client = new DeepSeekClient();
        $optionsList = [self::defaultModelOptions()];

        $failedErrors = [];
        $lastResult = ['success' => false, 'error' => 'AI助手模型服务暂时不可用', 'tokens' => 0];
        foreach ($optionsList as $options) {
            $result = $client->chatMessages($messages, $options);
            if (!empty($result['success'])) {
                return $result;
            }

            $lastResult = $result;
            $provider = (string) ($result['provider_label'] ?? ($options['provider_label'] ?? 'AI模型'));
            $failedErrors[] = $provider . ': ' . (string) ($result['error'] ?? '调用失败');
        }

        if (!empty($failedErrors)) {
            $lastResult['error'] = implode(' | ', $failedErrors);
        }
        return $lastResult;
    }

    private static function defaultModelOptions(): array
    {
        return DeepSeekClient::defaultModelOptions([
            'max_tokens' => 1600,
            'temperature' => 0.45,
            'retry_times' => 3,
            'retry_sleep_ms' => 1200,
        ]);
    }

    private static function defaultSystemPrompt(): string
    {
        return '你是世博头条 AI 助手，面向普通用户回答站内体育资讯、赛事、社区、彩票和加密行情相关问题。'
            . '必须优先依据提供的站内资料和实时上下文回答；资料不足时要直接说明不足并建议用户换关键词。'
            . '不要声称可以访问后台、源码、服务器或未提供的内部数据。'
            . '回答使用中文，结构清晰，语气专业克制。涉及赛事预测、彩票或加密行情时，必须说明仅供参考，不构成投资或购彩建议。';
    }
}