<?php

namespace App\Services;

use Illuminate\Http\Client\PendingRequest;
use Illuminate\Http\Client\RequestException;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Facades\Http;

class QuestionServiceApi
{
    public function __construct(
        protected string $baseUrl = '',
        protected int $timeout = 10,
        protected int $cacheTtl = 300,
    ) {
        $this->baseUrl = rtrim($this->baseUrl ?: config('question_bank.api_base', 'http://localhost:5015'), '/');
        $this->timeout = (int) config('question_bank.timeout', 10);
        $this->cacheTtl = (int) config('question_bank.cache_ttl', 300);
    }

    /**
     * 获取所有题目（分页）
     */
    public function listQuestions(int $page = 1, int $perPage = 50, array $filters = []): array
    {
        $cacheKey = sprintf(
            'questions-list-%d-%d-%s',
            $page,
            $perPage,
            md5(json_encode($filters))
        );

        return Cache::remember(
            $cacheKey,
            now()->addSeconds($this->cacheTtl),
            function () use ($page, $perPage, $filters): array {
                $query = array_filter([
                    'page' => $page,
                    'per_page' => $perPage,
                    'kp_code' => $filters['kp_code'] ?? null,
                    'difficulty' => $filters['difficulty'] ?? null,
                    'type' => $filters['type'] ?? null,
                    'skill' => $filters['skill'] ?? null,
                    'search' => $filters['search'] ?? null,
                ], fn ($value) => filled($value));

                $response = $this->request('GET', '/questions', $query);

                // 处理数学公式
                $data = $response['data'] ?? [];
                foreach ($data as &$question) {
                    // 使用数学公式处理器处理题目数据
                    $question = MathFormulaProcessor::processQuestionData($question);
                }

                return [
                    'data' => $data,
                    'meta' => $response['meta'] ?? [
                        'page' => $page,
                        'per_page' => $perPage,
                        'total' => is_array($response) ? count($response) : 0,
                        'total_pages' => 1,
                    ],
                ];
            }
        );
    }

    /**
     * 获取题目统计信息
     */
    public function getStatistics(): array
    {
        $cacheKey = 'question-statistics';

        return Cache::remember(
            $cacheKey,
            now()->addSeconds($this->cacheTtl),
            function (): array {
                $response = $this->request('GET', '/questions/statistics');

                return $response ?? [
                    'total' => 0,
                    'by_difficulty' => [],
                    'by_kp' => [],
                    'by_source' => [],
                ];
            }
        );
    }

    /**
     * 根据 kp_code 获取题目
     */
    public function getQuestionsByKpCode(string $kpCode, int $limit = 100): array
    {
        $response = $this->request('GET', '/questions', [
            'kp_code' => $kpCode,
            'limit' => $limit,
        ]);

        // 处理数学公式
        if ($response && isset($response['data']) && is_array($response['data'])) {
            foreach ($response['data'] as &$question) {
                $question = MathFormulaProcessor::processQuestionData($question);
            }
        }

        return $response;
    }

    /**
     * 语义搜索题目
     */
    public function searchQuestions(string $query, int $limit = 20): array
    {
        $cacheKey = sprintf('question-search-%s-%d', md5($query), $limit);

        return Cache::remember(
            $cacheKey,
            now()->addSeconds($this->cacheTtl),
            function () use ($query, $limit): array {
                try {
                    $response = $this->request('POST', '/questions/search', [
                        'query' => $query,
                        'limit' => $limit,
                    ]);

                    // 处理数学公式
                    if ($response && is_array($response)) {
                        $response = MathFormulaProcessor::processArray($response, [
                            'stem', 'content', 'question_text', 'answer', 'explanation'
                        ]);
                    }

                    return $response ?? [];
                } catch (\Exception $e) {
                    \Log::error('Question search failed: ' . $e->getMessage());
                    return [];
                }
            }
        );
    }

    /**
     * 获取单个题目详情
     */
    public function getQuestionById(int $id): ?array
    {
        $cacheKey = "question-{$id}";

        return Cache::remember(
            $cacheKey,
            now()->addSeconds($this->cacheTtl),
            function () use ($id): ?array {
                try {
                    $response = $this->request('GET', "/questions/{$id}");

                    // 处理数学公式
                    if ($response && is_array($response)) {
                        $response = MathFormulaProcessor::processQuestionData($response);
                    }

                    return $response ?: null;
                } catch (\Exception $e) {
                    \Log::error("Failed to get question {$id}: " . $e->getMessage());
                    return null;
                }
            }
        );
    }

    /**
     * 创建题目（通过 AI 生成）
     */
    public function generateQuestions(array $params): array
    {
        try {
            $response = $this->request('POST', '/questions/generate', $params);

            return $response ?? [
                'success' => false,
                'message' => '生成失败',
            ];
        } catch (\Exception $e) {
            \Log::error('Question generation failed: ' . $e->getMessage());
            return [
                'success' => false,
                'message' => '生成失败：' . $e->getMessage(),
            ];
        }
    }

    /**
     * 导入题目（JSON 批量导入）
     */
    public function importQuestions(array $questions): array
    {
        try {
            $response = $this->request('POST', '/questions/import', [
                'questions' => $questions,
            ]);

            return $response ?? [
                'success' => false,
                'message' => '导入失败',
            ];
        } catch (\Exception $e) {
            \Log::error('Question import failed: ' . $e->getMessage());
            return [
                'success' => false,
                'message' => '导入失败：' . $e->getMessage(),
            ];
        }
    }

    /**
     * 删除题目
     */
    public function deleteQuestion(int $id): bool
    {
        try {
            $response = $this->request('DELETE', "/questions/{$id}");
            return $response['success'] ?? false;
        } catch (\Exception $e) {
            \Log::error("Failed to delete question {$id}: " . $e->getMessage());
            return false;
        }
    }

    /**
     * 获取知识点选项（从知识图谱服务）
     */
    public function getKnowledgePointOptions(): array
    {
        try {
            // 使用新的知识图谱API
            $knowledgeApiBase = config('services.knowledge_api.base_url', 'http://localhost:5011');
            $response = Http::timeout(10)
                ->get($knowledgeApiBase . '/graph/export');

            if ($response->successful()) {
                $data = $response->json();
                $nodes = $data['nodes'] ?? [];

                // 转换为键值对格式
                $options = [];
                foreach ($nodes as $node) {
                    $code = $node['kp_code'] ?? null;
                    $name = $node['cn_name'] ?? null;
                    
                    if ($code && $name) {
                        $options[$code] = $name;
                    }
                }

                // 按代码排序
                ksort($options);

                \Log::info('成功获取知识点选项', ['count' => count($options)]);
                return $options;
            }

            \Log::warning('知识图谱API调用失败', [
                'status' => $response->status(),
                'url' => $knowledgeApiBase . '/graph/export'
            ]);
        } catch (\Exception $e) {
            \Log::error('Failed to get knowledge points: ' . $e->getMessage());
        }

        // 返回空数组作为fallback
        return [];
    }

    /**
     * 获取提示词模板列表
     */
    public function listPrompts(?string $type = null, ?string $active = null): array
    {
        $query = array_filter([
            'type' => $type,
            'active' => $active,
        ], fn ($value) => filled($value));

        try {
            $response = $this->request('GET', '/prompts', $query);
            return $response ?? [];
        } catch (\Exception $e) {
            \Log::error('Failed to get prompts: ' . $e->getMessage());
            return [];
        }
    }

    /**
     * 保存提示词模板
     */
    public function savePrompt(array $data): array
    {
        try {
            // 先尝试更新
            $response = $this->request('PUT', '/prompts/default', $data);

            // 如果更新失败（可能不存在），则尝试创建
            if (!isset($response['success']) || !$response['success']) {
                $response = $this->request('POST', '/prompts', $data);
            }

            return $response ?? [
                'success' => true,
                'message' => '提示词保存成功',
            ];
        } catch (\Exception $e) {
            \Log::error('Failed to save prompt: ' . $e->getMessage());
            return [
                'success' => false,
                'message' => '保存失败：' . $e->getMessage(),
            ];
        }
    }

    /**
     * @throws RequestException
     * @return mixed
     */
    protected function request(string $method, string $path, array $params = []): mixed
    {
        $response = $this->http()->send($method, ltrim($path, '/'), [
            'query' => $method === 'GET' ? $params : null,
            'json' => $method !== 'GET' ? $params : null,
        ]);

        return $response->throw()->json();
    }

    protected function http(): PendingRequest
    {
        return Http::baseUrl($this->baseUrl)
            ->acceptJson()
            ->timeout($this->timeout)
            ->retry(2, 200)
            ->withHeaders([
                'User-Agent' => 'Laravel/' . (app()->version()),
                'Accept' => 'application/json',
            ]);
    }

}