package com.kaidi.oa.web;

import com.kaidi.oa.common.ApiException;
import com.kaidi.oa.common.ApiResp;
import com.kaidi.oa.common.NotFoundException;
import com.kaidi.oa.domain.Handover;
import com.kaidi.oa.repository.HandoverRepository;
import org.springframework.web.bind.annotation.DeleteMapping;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PatchMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.time.Instant;
import java.util.List;

/**
 * Work handover center (工作交接). handoverType is one of 离职交接 / 调动交接 /
 * 轮岗交接; status flows 进行中 -> 已完成 -> 已确认.
 */
@RestController
@RequestMapping("/api/oa/handovers")
public class HandoverController {

    public static final String STATUS_IN_PROGRESS = "进行中";
    public static final String STATUS_DONE = "已完成";
    public static final String STATUS_CONFIRMED = "已确认";

    /** Accepted handover statuses (交接全过程)。 */
    public static final List<String> HANDOVER_STATUSES =
            List.of(STATUS_IN_PROGRESS, STATUS_DONE, STATUS_CONFIRMED);

    private final HandoverRepository handoverRepo;

    public HandoverController(HandoverRepository handoverRepo) {
        this.handoverRepo = handoverRepo;
    }

    @GetMapping
    public ApiResp<List<Handover>> list(@RequestParam(required = false) String status) {
        List<Handover> list;
        if (status != null && !status.isBlank()) {
            list = handoverRepo.findByStatus(status);
        } else {
            list = handoverRepo.findAll();
        }
        return ApiResp.ok(list);
    }

    @GetMapping("/{id}")
    public ApiResp<Handover> get(@PathVariable Long id) {
        return ApiResp.ok(handoverRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("handover not found: " + id)));
    }

    /** 新建/更新共用请求体——含结构化字段（需求功能14）。 */
    public record HandoverRequest(
            String handoverPerson, String receiver, String dept, String handoverType,
            String items, String status, String handoverDate,
            // 结构化字段（可空）
            String jobDuties, String pendingTaskList,
            String systemAccounts, String keyContacts, String filePaths) {
    }

    /** @deprecated 旧签名保留别名，前端升级后可删 */
    public record CreateHandoverRequest(
            String handoverPerson, String receiver, String dept, String handoverType,
            String items, String status, String handoverDate) {
    }

    @PostMapping
    public ApiResp<Handover> create(@RequestBody HandoverRequest req) {
        if (req.handoverPerson() == null || req.handoverPerson().isBlank()) {
            throw new ApiException(400, "handoverPerson is required");
        }
        Handover h = new Handover();
        applyFields(h, req);
        h.setStatus(req.status() == null || req.status().isBlank() ? STATUS_IN_PROGRESS : req.status());
        h.setCreatedAt(Instant.now());
        return ApiResp.ok(handoverRepo.save(h));
    }

    /**
     * PATCH /{id} -> partial update incl. status progression
     * (提交 进行中->已完成 / 确认 已完成->已确认). Only non-null fields are applied;
     * a supplied status must belong to {@link #HANDOVER_STATUSES}.
     */
    @PatchMapping("/{id}")
    public ApiResp<Handover> update(@PathVariable Long id, @RequestBody HandoverRequest req) {
        Handover h = handoverRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("handover not found: " + id));
        if (req.handoverPerson() != null) {
            if (req.handoverPerson().isBlank()) {
                throw new ApiException(400, "handoverPerson is required");
            }
        }
        applyFields(h, req);
        if (req.status() != null && !req.status().isBlank()) {
            if (!HANDOVER_STATUSES.contains(req.status())) {
                throw new ApiException(400, "invalid status: " + req.status()
                        + "; expected one of " + HANDOVER_STATUSES);
            }
            h.setStatus(req.status());
        }
        return ApiResp.ok(handoverRepo.save(h));
    }

    /** DELETE /{id} -> remove a handover record. */
    @DeleteMapping("/{id}")
    public ApiResp<Void> delete(@PathVariable Long id) {
        if (!handoverRepo.existsById(id)) {
            throw new NotFoundException("handover not found: " + id);
        }
        handoverRepo.deleteById(id);
        return ApiResp.ok(null);
    }

    // ====== 一键生成交接清单（需求功能14）======

    public record ChecklistSection(String section, java.util.List<String> items) {}
    public record ChecklistResult(Long handoverId, String handoverPerson, String receiver,
                                   String handoverDate, java.util.List<ChecklistSection> sections) {}

    /**
     * POST /{id}/generate-checklist
     * 根据结构化字段（岗位职责/在办事项/系统账号/关键联系人/文件路径/遗留 items）
     * 一键组装"工作交接清单"，返回分节结构，前端可直接渲染或打印。
     */
    @PostMapping("/{id}/generate-checklist")
    public ApiResp<ChecklistResult> generateChecklist(@PathVariable Long id) {
        Handover h = handoverRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("handover not found: " + id));
        java.util.List<ChecklistSection> sections = new java.util.ArrayList<>();

        // 1. 岗位职责
        if (h.getJobDuties() != null && !h.getJobDuties().isBlank()) {
            sections.add(new ChecklistSection("岗位职责",
                    splitLines(h.getJobDuties())));
        }

        // 2. 在办事项清单
        if (h.getPendingTaskList() != null && !h.getPendingTaskList().isBlank()) {
            sections.add(new ChecklistSection("在办事项清单",
                    splitLines(h.getPendingTaskList())));
        }

        // 3. 常用系统账号
        if (h.getSystemAccounts() != null && !h.getSystemAccounts().isBlank()) {
            sections.add(new ChecklistSection("常用系统账号",
                    splitLines(h.getSystemAccounts())));
        }

        // 4. 关键联系人
        if (h.getKeyContacts() != null && !h.getKeyContacts().isBlank()) {
            sections.add(new ChecklistSection("关键联系人",
                    splitLines(h.getKeyContacts())));
        }

        // 5. 重要文件路径
        if (h.getFilePaths() != null && !h.getFilePaths().isBlank()) {
            sections.add(new ChecklistSection("重要文件路径",
                    splitLines(h.getFilePaths())));
        }

        // 6. 其他事项（来自原 items 自由文本）
        if (h.getItems() != null && !h.getItems().isBlank()) {
            sections.add(new ChecklistSection("其他交接事项",
                    splitLines(h.getItems())));
        }

        if (sections.isEmpty()) {
            throw new ApiException(409, "交接单尚无任何结构化内容，请先填写岗位职责/在办事项/系统账号等字段");
        }

        return ApiResp.ok(new ChecklistResult(h.getId(), h.getHandoverPerson(),
                h.getReceiver(), h.getHandoverDate(), sections));
    }

    // ====== 私有方法 ======

    private void applyFields(Handover h, HandoverRequest req) {
        if (req.handoverPerson() != null && !req.handoverPerson().isBlank()) h.setHandoverPerson(req.handoverPerson());
        if (req.receiver() != null) h.setReceiver(req.receiver());
        if (req.dept() != null) h.setDept(req.dept());
        if (req.handoverType() != null) h.setHandoverType(req.handoverType());
        if (req.items() != null) h.setItems(req.items());
        if (req.handoverDate() != null) h.setHandoverDate(req.handoverDate());
        if (req.jobDuties() != null) h.setJobDuties(req.jobDuties());
        if (req.pendingTaskList() != null) h.setPendingTaskList(req.pendingTaskList());
        if (req.systemAccounts() != null) h.setSystemAccounts(req.systemAccounts());
        if (req.keyContacts() != null) h.setKeyContacts(req.keyContacts());
        if (req.filePaths() != null) h.setFilePaths(req.filePaths());
    }

    /** 按换行或分号拆分为非空行列表。 */
    private java.util.List<String> splitLines(String raw) {
        java.util.List<String> out = new java.util.ArrayList<>();
        for (String part : raw.split("[\\r\\n;；]+")) {
            String line = part.trim();
            if (!line.isEmpty()) out.add(line);
        }
        return out.isEmpty() ? java.util.List.of(raw.trim()) : out;
    }
}