<?php

namespace app\common;

use app\common\service\LLMService;
use Smalot\PdfParser\Parser as PdfParser;
use think\Db;
use think\Env;
use think\Exception;

/**
 * 从用户简历文件提取文本，调用与参考文献校对相同的 LLMService 解析用户基本信息。
 */
class UserInfoFromFileService
{
    const CV_BASE_URL_DEFAULT = 'https://submission.tmrjournals.com/public/reviewer/';

    /** @var LLMService */
    private $llm;

    public function __construct(LLMService $llm = null)
    {
        $this->llm = $llm ?: new LLMService();
    }

    /**
     * 按 user_id 查 user_cv，取最新一条简历解析。
     *
     * @param int $userId
     * @return array
     */
    public function parseFromUserId($userId)
    {
        $userId = intval($userId);
        if ($userId <= 0) {
            throw new Exception('user_id 无效');
        }

        $row = Db::name('user_cv')
            ->where('user_id', $userId)
            ->where('state', 0)
            ->order('ctime desc')
            ->find();
        if (empty($row) || trim((string) $row['cv']) === '') {
            throw new Exception('未找到该用户的简历（user_cv）');
        }

        $cvRel   = $this->normalizeCvRelativePath($row['cv']);
        $cvUrl   = $this->buildCvUrl($cvRel);
        $local   = $this->resolveLocalCvPath($cvRel);
        $temp    = false;
        $filePath = $local;

        if ($filePath === '' || !is_file($filePath)) {
            $filePath = $this->downloadCvToTemp($cvUrl, $cvRel);
            $temp     = true;
        }

        try {
            $result = $this->parseFromFile($filePath);
        } finally {
            if ($temp && is_file($filePath)) {
                @unlink($filePath);
            }
        }

        $result['user_id']   = $userId;
        $result['user_cv_id'] = intval($row['user_cv_id'] ?? 0);
        $result['cv']        = $cvRel;
        $result['cv_url']    = $cvUrl;

        return $result;
    }

    /**
     * @param string $filePath 服务器本地绝对路径
     * @return array
     */
    public function parseFromFile($filePath)
    {
        $filePath = trim((string) $filePath);
        if ($filePath === '' || !is_file($filePath)) {
            throw new Exception('文件不存在');
        }

        $text = trim($this->extractFileText($filePath));
        if ($text === '') {
            throw new Exception('未能从文件中提取到文本');
        }

        $text = $this->sanitizeUtf8($text);
        $maxChars = max(1000, (int) Env::get('promotion.promotion_llm_max_chars', 2500));
        if (mb_strlen($text) > $maxChars) {
            $text = mb_substr($text, 0, $maxChars) . "\n...(truncated)";
        }

        $llmResult = $this->parseUserInfoWithLlm($text);

        return [
            'file'          => basename($filePath),
            'text_length'   => mb_strlen($text),
            'text_preview'  => mb_substr($text, 0, 600),
            'user_info'     => $llmResult['user_info'],
            'llm_raw'       => $llmResult['raw'],
        ];
    }

    private function normalizeCvRelativePath($cv)
    {
        $cv = trim(str_replace('\\', '/', (string) $cv));
        if ($cv === '') {
            return '';
        }
        if (preg_match('#^https?://#i', $cv)) {
            return $cv;
        }
        return ltrim($cv, '/');
    }

    private function buildCvUrl($cvRel)
    {
        if (preg_match('#^https?://#i', $cvRel)) {
            return $cvRel;
        }
        $base = rtrim(trim((string) Env::get('reviewer.cv_base_url', self::CV_BASE_URL_DEFAULT)), '/') . '/';
        return $base . $cvRel;
    }

    private function resolveLocalCvPath($cvRel)
    {
        if (preg_match('#^https?://#i', $cvRel)) {
            return '';
        }
        $path = ROOT_PATH . 'public' . DS . 'reviewer' . DS . str_replace('/', DS, $cvRel);
        return is_file($path) ? $path : '';
    }

    private function downloadCvToTemp($url, $cvRel)
    {
        $ext = strtolower(pathinfo(parse_url($cvRel, PHP_URL_PATH) ?: $cvRel, PATHINFO_EXTENSION));
        if ($ext === '') {
            $ext = 'dat';
        }

        $saveDir = ROOT_PATH . 'runtime' . DS . 'user_file_parse';
        if (!is_dir($saveDir)) {
            @mkdir($saveDir, 0755, true);
        }
        $path = $saveDir . DS . date('YmdHis') . '_' . uniqid('', true) . '.' . $ext;

        $ch = curl_init($url);
        curl_setopt_array($ch, [
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_FOLLOWLOCATION => true,
            CURLOPT_CONNECTTIMEOUT => 15,
            CURLOPT_TIMEOUT        => 90,
            CURLOPT_SSL_VERIFYPEER => false,
            CURLOPT_SSL_VERIFYHOST => 0,
        ]);
        $body = curl_exec($ch);
        $code = (int) curl_getinfo($ch, CURLINFO_HTTP_CODE);
        $err  = curl_error($ch);
        curl_close($ch);

        if ($body === false || $code < 200 || $code >= 300) {
            throw new Exception('下载简历失败（HTTP ' . $code . '）: ' . $url . ($err !== '' ? ' ' . $err : ''));
        }
        if (@file_put_contents($path, $body) === false) {
            throw new Exception('保存简历临时文件失败');
        }
        return $path;
    }

    private function extractFileText($filePath)
    {
        $ext = strtolower(pathinfo($filePath, PATHINFO_EXTENSION));

        if (in_array($ext, ['txt', 'text', 'md', 'csv', 'log'], true)) {
            $raw = @file_get_contents($filePath);
            return is_string($raw) ? $raw : '';
        }

        if ($ext === 'pdf') {
            return $this->extractPdfText($filePath);
        }

        if (in_array($ext, ['doc', 'docx'], true)) {
            return $this->extractDocxText($filePath);
        }

        // 未识别扩展名：先尝试 Word，再尝试 PDF，最后按纯文本读
        $text = $this->tryExtractDocxText($filePath);
        if ($text !== '') {
            return $text;
        }
        $text = $this->tryExtractPdfText($filePath);
        if ($text !== '') {
            return $text;
        }

        $raw = @file_get_contents($filePath);
        if (!is_string($raw) || $raw === '') {
            return '';
        }
        if ($this->looksLikeBinary($raw)) {
            throw new Exception('不支持的简历文件格式: .' . ($ext !== '' ? $ext : 'unknown'));
        }
        return $raw;
    }

    private function extractPdfText($filePath)
    {
        $text = $this->tryExtractPdfText($filePath);
        if ($text === '') {
            throw new Exception('PDF 文本提取失败，请确认已安装 smalot/pdfparser：composer require smalot/pdfparser');
        }
        return $text;
    }

    private function tryExtractPdfText($filePath)
    {
        if (!class_exists(PdfParser::class)) {
            \think\Log::warning('UserInfoFromFile: smalot/pdfparser not installed');
            return '';
        }
        try {
            $parser = new PdfParser();
            $pdf    = $parser->parseFile($filePath);
            $text   = $pdf->getText();
            return is_string($text) ? $text : '';
        } catch (\Throwable $e) {
            \think\Log::warning('UserInfoFromFile PDF extract: ' . $e->getMessage());
            return '';
        }
    }

    private function extractDocxText($filePath)
    {
        $text = $this->tryExtractDocxText($filePath);
        if ($text === '') {
            throw new Exception('Word 文档文本提取失败');
        }
        return $text;
    }

    private function tryExtractDocxText($filePath)
    {
        if (!function_exists('docxReader')) {
            return '';
        }
        try {
            $text = docxReader($filePath);
            return is_string($text) ? $text : '';
        } catch (\Throwable $e) {
            \think\Log::warning('UserInfoFromFile docxReader: ' . $e->getMessage());
            return '';
        }
    }

    private function looksLikeBinary($raw)
    {
        if (strpos($raw, "\0") !== false) {
            return true;
        }
        $sample = substr($raw, 0, 4096);
        if ($sample === '') {
            return false;
        }
        $nonPrintable = preg_match_all('/[\x00-\x08\x0B\x0C\x0E-\x1F]/', $sample);
        return $nonPrintable > 10;
    }

    private function parseUserInfoWithLlm($text)
    {
        $system = <<<'PROMPT'
你是学术人员信息抽取助手。根据用户上传的简历、简介或申请表文本，提取可用于期刊投稿/审稿人档案的基本信息。

只输出一个 JSON 对象，不要 markdown，不要解释。字段说明：
- realname: 中文姓名；若只有拼音可填拼音；无法判断则空字符串
- email: 邮箱
- phone: 手机或电话
- orcid: ORCID 号（仅数字与连字符）
- technical: 职称/职务（如教授、副主任护师、医学博士）
- field: 主要研究领域，中文，1～3 个词用顿号分隔
- company: 当前主要任职机构/工作单位（必填优先提取；填完整机构名，如「中南大学湘雅二医院」「暨南大学」，不要只写科室；多机构取最主要或最近一条）
- department: 所在科室/部门/学院（如感染科、药学院）
- country: 国家，默认中国可填「中国」
- introduction: 100字以内中文简介（职务+机构+方向）

缺失字段用空字符串 ""，不要编造。机构信息请从「工作单位」「任职」「所在单位」「affiliation」等段落提取。
PROMPT;

        \think\Log::info('UserInfoFromFile user head: ' . mb_substr($text, 0, 600));

        $raw = $this->llm->requestChat([
            ['role' => 'system', 'content' => $system],
            ['role' => 'user', 'content' => "请从以下文本提取用户信息：\n\n" . $text],
        ], 0.1);

        if ($raw === null) {
            throw new Exception('大模型请求失败，请检查 .env 中 [promotion] PROMOTION_LLM_URL / PROMOTION_LLM_MODEL（与参考文献校对相同）');
        }

        $parsed = $this->llm->parseJsonResponse($raw);
        if ($parsed === null) {
            throw new Exception('大模型返回无法解析为 JSON：' . mb_substr($raw, 0, 200));
        }

        return [
            'user_info' => $this->normalizeUserInfo($parsed),
            'raw'       => $raw,
        ];
    }

    private function normalizeUserInfo(array $parsed)
    {
        $keys = ['realname', 'email', 'phone', 'orcid', 'technical', 'field', 'company', 'department', 'country', 'introduction'];
        $out  = [];
        foreach ($keys as $k) {
            $out[$k] = trim((string) ($parsed[$k] ?? ''));
        }

        // 机构：兼容大模型可能返回的别名字段
        if ($out['company'] === '') {
            foreach (['机构', '单位', 'institution', 'affiliation', 'organization', 'org', '工作单位', '任职单位'] as $alias) {
                $val = trim((string) ($parsed[$alias] ?? ''));
                if ($val !== '') {
                    $out['company'] = $val;
                    break;
                }
            }
        }

        if ($out['orcid'] !== '') {
            $out['orcid'] = preg_replace('/\s+/', '', $out['orcid']);
        }

        // 对外同时返回 institution（与 company 同值）
        $out['institution'] = $out['company'];

        return $out;
    }

    private function sanitizeUtf8($text)
    {
        $text = (string) $text;
        if (function_exists('mb_convert_encoding')) {
            $text = mb_convert_encoding($text, 'UTF-8', 'UTF-8');
        }
        if (function_exists('iconv')) {
            $fixed = @iconv('UTF-8', 'UTF-8//IGNORE', $text);
            if (is_string($fixed)) {
                $text = $fixed;
            }
        }
        return $text;
    }
}