package com.guo.learningprogresstracker.service.impl;

import com.guo.learningprogresstracker.entity.StudyReportsEntity;
import com.guo.learningprogresstracker.entity.TaskApplicationEntity;
import com.guo.learningprogresstracker.entity.TaskEntity;
import com.guo.learningprogresstracker.service.MindMapAiClient;
import com.guo.learningprogresstracker.utils.MindMapNode;
import com.guo.learningprogresstracker.utils.MindMapTreeTool;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.Optional;
import java.util.stream.Collectors;

/**
 * 远程 AI 思维导图生成客户端。
 * <p>通过 lpt-ai 服务（{@code lpt.ai-service.url}）调用大语言模型生成思维导图。
 * 未配置 lpt-ai 时不可用，会回退到 {@link BuiltinMindMapGenerator}。</p>
 */
@Slf4j
@Component
@RequiredArgsConstructor
public class RemoteAiMindMapClient implements MindMapAiClient {

    private final AiServiceClient aiServiceClient;

    @Override
    public boolean isAvailable() {
        return aiServiceClient.isConfigured();
    }

    @Override
    public String generatorName() {
        return "AI";
    }

    @Override
    public Optional<MindMapNode> generate(TaskEntity task,
                                          List<StudyReportsEntity> reports,
                                          List<TaskApplicationEntity> applications,
                                          String clientHint) {
        if (!isAvailable()) {
            return Optional.empty();
        }

        // 提取学习报告的内容文本
        List<String> reportTexts = reports.stream()
                .map(StudyReportsEntity::getContent)
                .filter(c -> c != null && !c.isBlank())
                .collect(Collectors.toList());

        if (reportTexts.isEmpty()) {
            return Optional.empty();
        }

        Optional<String> optOutline = aiServiceClient.generateMindMap(
                task.getTaskName(),
                task.getTaskDescription(),
                reportTexts
        );

        if (optOutline.isEmpty() || optOutline.get().isBlank()) {
            log.warn("RemoteAiMindMapClient: lpt-ai 返回空大纲，降级");
            return Optional.empty();
        }

        String outline = optOutline.get();
        MindMapNode root = MindMapTreeTool.parseOutline(outline);
        log.info("RemoteAiMindMapClient: 为任务[{}]生成 AI 导图，共 {} 个节点，{} 层",
                task.getTaskNum(), MindMapTreeTool.countNodes(root), MindMapTreeTool.maxDepth(root));
        return Optional.of(root);
    }
}