package com.xly.web;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.xly.agent.AgentIdentity;
import com.xly.service.AuditService;
import com.xly.service.AuthzService;
import com.xly.service.ConversationService;
import com.xly.service.ErpClient;
import com.xly.service.FormResolverService;
import com.xly.service.LedgerService;
import com.xly.service.OpService;
import com.xly.service.StateService;
import org.springframework.http.HttpStatus;
import org.springframework.web.server.ResponseStatusException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestHeader;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/**
 * 写操作确认端点（**确定性、不经过 LLM**）—— 人在环写入闭环的执行侧。
 *
 * <p>用户在对话框点【确认】-> {@code /confirm} 才真正调 ERP 执行；点【取消】-> {@code /cancel}。
 * 覆盖全部 op 类型：create（含报价这类多表主-从）、update、delete、invalid/cancelInvalid、
 * examine/cancelExamine。执行完回写 {@code ai_op_queue} 状态 + 审计。
 *
 * <p>两条执行路径由 {@code erp.exec-staging.enabled} 切换：直连 ERP 通用写接口（本地默认），
 * 或委托 ERP 侧暂存执行器 {@code /ai/execStaging}（生产路径，事务化、以用户身份执行）。
 *
 * <p>当前**恒同步**：确认即执行并同步返回终态。架构 §10 设计的「auto 流程异步 + 卡片三态 + SSE 终态推送」
 * 尚未实现（见 docs/agent-architecture.md §18）。
 */
@RestController
@RequestMapping("/api/agent/op")
public class OpController {

    private static final Logger log = LoggerFactory.getLogger(OpController.class);

    private final OpService ops;
    private final ErpClient erp;
    private final AuditService audit;
    private final ObjectMapper mapper;
    private final LedgerService ledger;
    private final StateService state;
    private final AuthzService authz;
    private final ConversationService conversations;
    private final FormResolverService resolver;

    /** true=确认后委托 ERP 侧暂存执行器（/ai/execStaging，§10 生产路径）；false=xlyAi 直连 ERP 通用写接口执行。 */
    @org.springframework.beans.factory.annotation.Value("${erp.exec-staging.enabled:false}")
    private boolean execStagingEnabled;

    public OpController(OpService ops, ErpClient erp, AuditService audit, ObjectMapper mapper,
                        LedgerService ledger, StateService state,
                        AuthzService authz, ConversationService conversations,
                        FormResolverService resolver) {
        this.ops = ops;
        this.erp = erp;
        this.audit = audit;
        this.mapper = mapper;
        this.ledger = ledger;
        this.state = state;
        this.authz = authz;
        this.conversations = conversations;
        this.resolver = resolver;
    }

    /** 确认/取消的结果落事件日志（rightPush 原子，流式输出中途点确认也不覆盖对话事件）——LLM 下轮经投影即知这单已执行/失败/取消。 */
    private void recordOutcome(String conv, String opId, String status, String msg, String description) {
        if (conv == null || conv.isBlank() || "null".equals(conv)) {
            return;
        }
        try {
            ledger.append(conv, "cancelled".equals(status) ? "cancel" : "confirm", Map.of(
                    "opId", opId == null ? "" : opId,
                    "status", status,
                    "msg", msg == null ? "" : msg,
                    "description", description == null ? "" : description));
            state.updateDocStage(conv, opId, status);
        } catch (Exception e) {
            log.warn("record op outcome failed (conv={}, op={}): {}", conv, opId, e.getMessage());
        }
    }

    /**
     * 会话里最近一条待确认操作（前端每轮结束后轮询，用于渲染确认卡片）。
     * 需登录且只能查自己的会话；只回渲染必需的字段——绝不外泄 sPayload/内部表名等。
     */
    @GetMapping("/pending")
    public Map<String, Object> pending(@RequestParam("conversationId") String conversationId,
                                       @RequestHeader(value = "Authorization", required = false) String authToken) {
        String uid = requireLogin(authToken).userId();
        if (!conversations.owns(uid, conversationId)) {
            throw new ResponseStatusException(HttpStatus.FORBIDDEN, "无权访问该会话");
        }
        Map<String, Object> op = ops.pending(conversationId);
        if (op == null) {
            return Map.of();
        }
        Map<String, Object> out = new LinkedHashMap<>();
        out.put("opId", op.get("sId"));
        out.put("summary", op.get("sDescription"));
        out.put("status", op.get("sStatus"));
        return out;
    }

    /**
     * 确认执行：调 ERP 执行暂存的写操作，回写状态。
     * <p>{@code Authorization} 头（可空）= 用户浏览器里的 ERP 登录 token，透传给 ERP 使执行以用户身份
     * 进行；为空则回退 dev-login。绝不因用户 token 缺失而静默提权（见 ErpClient.canRelogin）。
     */
    @PostMapping("/{id}/confirm")
    public Map<String, Object> confirm(@PathVariable("id") String id,
                                       @RequestHeader(value = "Authorization", required = false) String authToken) {
        AgentIdentity me = requireLogin(authToken);
        Map<String, Object> op = ops.get(id);
        if (op == null) {
            return result("failed", "找不到该操作", null);
        }
        requireOwner(me, op);
        if (!"draft".equals(String.valueOf(op.get("sStatus")))) {
            return result(String.valueOf(op.get("sStatus")), "该操作已处理过（" + op.get("sStatus") + "）", op);
        }
        // CAS 抢占：并发/重复确认只有一个能真正执行，杜绝同一张单被执行两次
        if (!ops.claim(id)) {
            Map<String, Object> cur = ops.get(id);
            String st = cur == null ? "unknown" : String.valueOf(cur.get("sStatus"));
            return result(st, "该操作正在处理或已处理过（" + st + "）", op);
        }
        String uid = str(op.get("sUserId"));
        String conv = str(op.get("sConversationId"));
        String target = str(op.get("sTargetTable")) + "#" + str(op.get("sTargetBillId"));
        String detail = str(op.get("sDescription"));

        // 生产路径：委托 ERP 侧暂存执行器（它以用户身份执行、事务化并自行回写 ai_op_queue 状态）。
        if (execStagingEnabled) {
            return confirmViaExecutor(id, op, authToken, uid, conv, target, detail);
        }
        try {
            String opType = str(op.get("sOpType"));
            JsonNode r;
            if ("create".equals(opType)) {
                JsonNode payload = mapper.readTree(str(op.get("sPayload")));
                if (payload.has("__tables__")) { // 报价等多表主-从创建
                    @SuppressWarnings("unchecked")
                    List<Map<String, Object>> tables = mapper.convertValue(payload.get("__tables__"), List.class);
                    if (!tables.isEmpty()) {
                        @SuppressWarnings("unchecked")
                        Map<String, Object> masterCol = (Map<String, Object>) tables.get(0).get("column");
                        refreshBillNo(masterCol, str(op.get("sTargetTable")), me.brandsId());
                    }
                    r = erp.createMulti(authToken, str(op.get("sTargetModuleId")), tables);
                } else {
                    @SuppressWarnings("unchecked")
                    Map<String, Object> columns = mapper.convertValue(payload, Map.class);
                    refreshBillNo(columns, str(op.get("sTargetTable")), me.brandsId());
                    r = erp.createForm(authToken, str(op.get("sTargetModuleId")), str(op.get("sTargetTable")), columns);
                }
            } else if ("delete".equals(opType)) {
                r = erp.deleteForm(authToken, str(op.get("sTargetModuleId")), str(op.get("sTargetTable")), str(op.get("sTargetBillId")));
            } else if ("invalid".equals(opType)) {
                boolean cancel = "cancel".equals(str(op.get("sNewValue"))); // cancel=复原/取消作废，toVoid=作废
                r = erp.invalidForm(authToken, str(op.get("sTargetModuleId")), str(op.get("sTargetTable")), str(op.get("sTargetBillId")), cancel);
            } else if ("examine".equals(opType)) {
                int iFlag = "0".equals(str(op.get("sNewValue"))) ? 0 : 1; // 1=审核 0=反审核
                r = erp.examineForm(authToken, str(op.get("sTargetModuleId")), str(op.get("sTargetBillId")), iFlag);
            } else {
                r = erp.updateForm(authToken,
                        str(op.get("sTargetModuleId")), str(op.get("sTargetTable")), str(op.get("sTargetBillId")),
                        str(op.get("sField")), str(op.get("sNewValue")));
            }
            int code = r.path("code").asInt(0);
            if (code == 1) {
                ops.setStatus(id, "executed", "操作成功");
                audit.log(uid, conv, "confirm", target, detail, true, "executed");
                recordOutcome(conv, id, "executed", null, detail);
                return result("executed", "已执行：" + op.get("sDescription"), op);
            }
            String msg = r.path("msg").asText("执行失败");
            ops.setStatus(id, "failed", msg);
            audit.log(uid, conv, "confirm", target, detail, false, msg);
            recordOutcome(conv, id, "failed", msg, detail);
            return result("failed", msg, op);
        } catch (Exception e) {
            log.warn("confirm op {} failed", id, e);
            ops.setStatus(id, "failed", e.getMessage());
            audit.log(uid, conv, "confirm", target, detail, false, e.getMessage());
            recordOutcome(conv, id, "failed", e.getMessage(), detail);
            return result("failed", "执行异常：" + e.getMessage(), op);
        }
    }

    /** 委托 ERP 侧暂存执行器执行（§10）；执行器自行回写 ai_op_queue 状态，这里只映射结果 + 审计。 */
    private Map<String, Object> confirmViaExecutor(String id, Map<String, Object> op, String authToken,
                                                   String uid, String conv, String target, String detail) {
        try {
            JsonNode r = erp.execStaging(authToken, id);
            String st = r.path("status").asText("failed");
            String msg = r.path("msg").asText("");
            boolean ok = "executed".equals(st);
            audit.log(uid, conv, "confirm", target, detail, ok, "execStaging:" + st + (msg.isEmpty() ? "" : (" " + msg)));
            recordOutcome(conv, id, ok ? "executed" : "failed", msg, detail);
            return result(ok ? "executed" : "failed",
                    ok ? ("已执行：" + op.get("sDescription")) : (msg.isEmpty() ? "执行失败" : msg), op);
        } catch (Exception e) {
            log.warn("execStaging confirm op {} failed", id, e);
            audit.log(uid, conv, "confirm", target, detail, false, e.getMessage());
            recordOutcome(conv, id, "failed", e.getMessage(), detail);
            return result("failed", "执行异常：" + e.getMessage(), op);
        }
    }

    /** 取消（需登录且必须是本人的操作）。 */
    @PostMapping("/{id}/cancel")
    public Map<String, Object> cancel(@PathVariable("id") String id,
                                      @RequestHeader(value = "Authorization", required = false) String authToken) {
        AgentIdentity me = requireLogin(authToken);
        Map<String, Object> op = ops.get(id);
        if (op != null) {
            requireOwner(me, op);
        }
        if (op != null && "draft".equals(String.valueOf(op.get("sStatus")))) {
            ops.setStatus(id, "cancelled", "用户取消");
            audit.log(str(op.get("sUserId")), str(op.get("sConversationId")), "cancel",
                    str(op.get("sTargetTable")) + "#" + str(op.get("sTargetBillId")),
                    str(op.get("sDescription")), true, "cancelled");
            recordOutcome(str(op.get("sConversationId")), id, "cancelled", null, str(op.get("sDescription")));
        }
        return result("cancelled", "已取消", op);
    }

    /**
     * 单号在 propose 时算的是当时的 MAX+1；期间别人建过单就会撞号，所以**执行前重新生成**。
     * 拿不到新号时保留旧号（由 ERP 侧唯一约束兜底），不因此中断执行。
     */
    private void refreshBillNo(Map<String, Object> columns, String table, String brandsId) {
        if (columns == null || !columns.containsKey("sBillNo")) {
            return;
        }
        String fresh = resolver.nextBillNo(table, brandsId);
        if (fresh != null && !fresh.isBlank()) {
            columns.put("sBillNo", fresh);
        }
    }

    /** 需登录（token 服务端内省）；未登录/过期 → 401。 */
    private AgentIdentity requireLogin(String authToken) {
        AgentIdentity id = authz.resolveIdentity(authToken);
        if (id == null) {
            throw new ResponseStatusException(HttpStatus.UNAUTHORIZED, "登录已过期或未登录");
        }
        return id;
    }

    /** 只有提议的发起人本人能确认/取消——否则任何人拿到 opId 就能替别人写库。 */
    private void requireOwner(AgentIdentity me, Map<String, Object> op) {
        String owner = str(op.get("sUserId"));
        if (owner == null || !owner.equals(me.userId())) {
            throw new ResponseStatusException(HttpStatus.FORBIDDEN, "无权处理该操作");
        }
    }

    private Map<String, Object> result(String status, String msg, Map<String, Object> op) {
        Map<String, Object> m = new LinkedHashMap<>();
        m.put("status", status);
        m.put("msg", msg);
        if (op != null) {
            m.put("opId", op.get("sId"));
            m.put("description", op.get("sDescription"));
        }
        return m;
    }

    private static String str(Object o) {
        return o == null ? null : o.toString();
    }
}