package com.xly.config;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.xly.agent.AgentIdentity;
import com.xly.agent.ReActAgent;
import com.xly.service.ErpClient;
import com.xly.service.FormResolverService;
import com.xly.service.OpService;
import com.xly.service.SystemPromptService;
import com.xly.tool.ErpReadTool;
import com.xly.tool.FormCollectTool;
import com.xly.tool.InteractionTool;
import com.xly.tool.KgQueryTool;
import com.xly.tool.ProposeWriteTool;
import com.xly.agent.ProjectedChatMemory;
import dev.langchain4j.model.chat.StreamingChatModel;
import dev.langchain4j.service.AiServices;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Component;

/**
 * 按「每次请求的身份」组装单一 ReAct agent（架构 §5/§7 的 per-call context）。
 *
 * <p>为什么按请求新建：LangChain4j 流式工具执行发生在模型 HTTP 回调线程，而非控制器工作线程，
 * ThreadLocal 不可靠。于是把 {@link AgentIdentity}（透传 token + 权限集）直接注入到**每请求新建**的
 * 工具实例里（ErpReadTool/ProposeWriteTool/FormCollectTool），从根上保证鉴权与 token 正确。
 *
 * <p>工具集**固定 6 个**（findForms/readFormData/lookupRecord/collectForm/proposeWrite/askUser），
 * 不再按意图分范围：n=50 基准显示分范围收不到准确率收益，反而破坏 KV-cache 前缀稳定性。
 * 无状态、全局的工具（{@link KgQueryTool}、{@link InteractionTool}）是单例、跨请求复用。
 */
@Component
public class AgentFactory {

    private final StreamingChatModel streamingModel;
    private final RedisChatMemoryStore memoryStore;
    private final SystemPromptService systemPromptService;

    private final ErpClient erp;
    private final JdbcTemplate jdbc;
    private final FormResolverService resolver;
    private final OpService ops;
    private final ObjectMapper mapper;

    private final KgQueryTool kgQueryTool;
    private final InteractionTool interactionTool;

    public AgentFactory(@Qualifier("agentStreamingModel") StreamingChatModel streamingModel,
                        RedisChatMemoryStore memoryStore,
                        SystemPromptService systemPromptService,
                        ErpClient erp, JdbcTemplate jdbc, FormResolverService resolver, OpService ops,
                        ObjectMapper mapper, KgQueryTool kgQueryTool, InteractionTool interactionTool) {
        this.streamingModel = streamingModel;
        this.memoryStore = memoryStore;
        this.systemPromptService = systemPromptService;
        this.erp = erp;
        this.jdbc = jdbc;
        this.resolver = resolver;
        this.ops = ops;
        this.mapper = mapper;
        this.kgQueryTool = kgQueryTool;
        this.interactionTool = interactionTool;
    }

    /**
     * 组装 ReAct agent：固定 6 工具 + 唯一 system prompt。{@code maxSequentialToolsInvocations}
     * 作为循环护栏，杜绝「反复追问同一问题」这类失控 ReAct 循环。
     */
    public ReActAgent build(AgentIdentity identity) {
        Object[] tools = new Object[]{kgQueryTool, interactionTool,
                new ErpReadTool(erp, resolver, identity),
                new ProposeWriteTool(erp, jdbc, ops, mapper, identity, resolver),
                new FormCollectTool(jdbc, resolver, identity, mapper)};

        return AiServices.builder(ReActAgent.class)
                .streamingChatModel(streamingModel)
                .tools(tools)
                .maxSequentialToolsInvocations(8) // 循环护栏：防止 askUser/工具无限自我循环
                // token 预算投影记忆：存储保完整、读取按预算收拢，旧工具结果压一行（见 ProjectedChatMemory）
                .chatMemoryProvider(memoryId -> new ProjectedChatMemory(memoryId, memoryStore, 6000, 80))
                .systemMessageProvider(memoryId -> systemPromptService.prompt())
                .build();
    }

    /** 供确定性「新增」路径直接构建 collectForm 表单（不经 LLM 工具选择）。 */
    public FormCollectTool formCollectTool(AgentIdentity identity) {
        return new FormCollectTool(jdbc, resolver, identity, mapper);
    }

    /** 供确定性「修改/作废/审核…」路径直接调 proposeWrite（不经 LLM 工具选择）。 */
    public ProposeWriteTool proposeWriteTool(AgentIdentity identity) {
        return new ProposeWriteTool(erp, jdbc, ops, mapper, identity, resolver);
    }
}