'use client';

import { useState, useMemo, useEffect } from 'react';
import { X, AlertTriangle } from 'lucide-react';
import { useDevTaskStore } from '@/stores/useDevTaskStore';
import { useTaskCategoryStore } from '@/stores/useTaskCategoryStore';
import { useRequirementStore } from '@/stores/useRequirementStore';
import { useMemberStore } from '@/stores/useMemberStore';
import { useAuthStore } from '@/stores/useAuthStore';
import { FilterSelect } from '@/components/FilterSelect';
import { WorkDateTimePicker } from '@/components/WorkDateTimePicker';
import { calcWorkHours, formatWorkHours, isoToLocal, localToISO } from '@/lib/work-hours';
import type { Priority } from '@/lib/derive';

interface Props {
  versionId: string;
  requirementIds: string[];
  versionDeadline?: string;
  onClose: () => void;
  onCreated?: () => void;
}

function defaultExpectedStart(): string {
  const d = new Date();
  d.setHours(9, 0, 0, 0);
  return isoToLocal(d.toISOString());
}

function defaultExpectedEnd(): string {
  const d = new Date();
  d.setHours(18, 0, 0, 0);
  return isoToLocal(d.toISOString());
}

export function DevTaskCreateModal({ versionId, requirementIds, versionDeadline, onClose, onCreated }: Props) {
  const { createTask, tasks } = useDevTaskStore();
  const { categories } = useTaskCategoryStore();
  const { requirements } = useRequirementStore();
  const { members } = useMemberStore();
  const user = useAuthStore((s) => s.user);

  const versionReqs = useMemo(
    () => requirements.filter((r) => requirementIds.includes(r.id)),
    [requirements, requirementIds],
  );
  const versionTasks = useMemo(
    () => tasks.filter((t) => t.versionId === versionId || requirementIds.includes(t.requirementId)),
    [tasks, requirementIds, versionId],
  );

  const [title, setTitle] = useState('');
  const [requirementId, setRequirementId] = useState(versionReqs[0]?.id || '');
  const [categoryId, setCategoryId] = useState(categories[0]?.id || '');
  const [assigneeId, setAssigneeId] = useState(user?.name || '');
  const [priority, setPriority] = useState<Priority>(versionReqs[0]?.priority || 'P2');
  const [priorityManuallySet, setPriorityManuallySet] = useState(false);
  const [expectedStartLocal, setExpectedStartLocal] = useState(defaultExpectedStart);
  const [expectedEndLocal, setExpectedEndLocal] = useState(defaultExpectedEnd);
  const [predecessorIds, setPredecessorIds] = useState<string[]>([]);
  const [description, setDescription] = useState('');
  const [overdueVersionReason, setOverdueVersionReason] = useState('');
  const [prototypeNotes, setPrototypeNotes] = useState('');

  useEffect(() => {
    if (categories[0] && !categoryId) setCategoryId(categories[0].id);
  }, [categories, categoryId]);

  const expectedStartISO = localToISO(expectedStartLocal);
  const expectedEndISO = localToISO(expectedEndLocal);

  const estimateHours = useMemo(() => {
    if (!expectedStartISO || !expectedEndISO) return 0;
    return calcWorkHours(expectedStartISO, expectedEndISO);
  }, [expectedStartISO, expectedEndISO]);

  const selectedReq = versionReqs.find((r) => r.id === requirementId);
  const effectivePriority = priorityManuallySet ? priority : (selectedReq?.priority || priority);

  const versionDeadlineISO = useMemo(() => {
    if (!versionDeadline) return null;
    const d = new Date(versionDeadline);
    if (isNaN(d.getTime())) return null;
    d.setHours(23, 59, 59, 999);
    return d.toISOString();
  }, [versionDeadline]);

  const isOverdueVersion = !!(expectedEndISO && versionDeadlineISO && expectedEndISO > versionDeadlineISO);
  const startBeforeEnd = expectedStartISO && expectedEndISO && expectedStartISO < expectedEndISO;

  const canSubmit =
    title.trim() &&
    requirementId &&
    categoryId &&
    assigneeId &&
    !!startBeforeEnd &&
    estimateHours > 0 &&
    (!isOverdueVersion || overdueVersionReason.trim());

  const handleSubmit = () => {
    if (!canSubmit) return;
    const reqRef = versionReqs.find((r) => r.id === requirementId);
    const references = [
      ...(reqRef ? [{ type: 'requirement' as const, id: reqRef.code, label: `${reqRef.code} ${reqRef.title}` }] : []),
      ...prototypeNotes.split(/[,，\s]+/).map((s) => s.trim()).filter(Boolean).map((note) => ({
        type: 'prototype_note' as const,
        id: note,
        label: note,
      })),
    ];
    createTask({
      versionId,
      requirementId,
      title: title.trim(),
      description: description.trim() || undefined,
      categoryId,
      assigneeId,
      reviewerId: undefined,
      priority: effectivePriority,
      expectedStartAt: expectedStartISO,
      expectedEndAt: expectedEndISO,
      estimateHours,
      actualStartAt: undefined,
      actualEndAt: undefined,
      status: 'todo',
      blockReason: undefined,
      blockedById: undefined,
      predecessorIds: predecessorIds.length > 0 ? predecessorIds : undefined,
      riskLevel: undefined,
      delayReason: undefined,
      overdueVersionReason: isOverdueVersion ? overdueVersionReason.trim() : undefined,
      references: references.length > 0 ? references : undefined,
      createdBy: user?.name || '系统',
    });
    onCreated?.();
    onClose();
  };

  return (
    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/40" onClick={onClose}>
      <div className="w-full max-w-3xl max-h-[92vh] overflow-y-auto rounded-2xl bg-[var(--bg-card)] border border-[var(--line)] p-6 shadow-[var(--shadow-md)]" onClick={(e) => e.stopPropagation()}>
        <div className="flex items-center justify-between mb-4">
          <h3 className="text-[14px] font-semibold text-[var(--ink)]">新建开发任务</h3>
          <button onClick={onClose} className="rounded-md p-1 hover:bg-[var(--bg-subtle)]"><X className="h-4 w-4 text-[var(--ink-muted)]" /></button>
        </div>
        <div className="space-y-3">
          <div>
            <label className="block text-[12px] text-[var(--ink-soft)] mb-1">任务标题 *</label>
            <input value={title} onChange={(e) => setTitle(e.target.value)} className="h-9 w-full rounded-lg border border-[var(--line)] bg-[var(--bg)] px-3 text-[13px] focus:border-[var(--accent)] focus:outline-none" placeholder="例如：排班界面开发" />
          </div>
          <div>
            <label className="block text-[12px] text-[var(--ink-soft)] mb-1">所属需求 *</label>
            <FilterSelect
              value={requirementId}
              onChange={(value) => {
                setRequirementId(value);
                const r = versionReqs.find((x) => x.id === value);
                if (r && !priorityManuallySet) setPriority(r.priority);
              }}
              options={versionReqs.map((r) => ({ value: r.id, label: `${r.code} ${r.title}` }))}
              placeholder="选择所属需求"
              showAllOption={false}
              className="w-full"
              labelClassName="max-w-[calc(100%-20px)]"
            />
          </div>
          <div className="grid grid-cols-2 gap-3">
            <div>
              <label className="block text-[12px] text-[var(--ink-soft)] mb-1">任务类型 *</label>
              <FilterSelect
                value={categoryId}
                onChange={setCategoryId}
                options={categories.map((c) => ({ value: c.id, label: c.name }))}
                placeholder="选择任务类型"
                showAllOption={false}
                className="w-full"
                labelClassName="max-w-[calc(100%-20px)]"
              />
            </div>
            <div>
              <label className="block text-[12px] text-[var(--ink-soft)] mb-1">负责人 *</label>
              <FilterSelect
                value={assigneeId}
                onChange={setAssigneeId}
                options={members.map((m) => ({ value: m.name, label: m.name }))}
                placeholder="选择负责人"
                showAllOption={false}
                className="w-full"
                labelClassName="max-w-[calc(100%-20px)]"
              />
            </div>
          </div>
          <div className="grid grid-cols-2 gap-3">
            <div>
              <label className="block text-[12px] text-[var(--ink-soft)] mb-1">预计开始 *</label>
              <WorkDateTimePicker
                value={expectedStartLocal}
                onChange={setExpectedStartLocal}
                placeholder="选择预计开始时间"
                defaultHour={9}
                className="bg-[var(--bg)]"
              />
            </div>
            <div>
              <label className="block text-[12px] text-[var(--ink-soft)] mb-1">预计截止 *</label>
              <WorkDateTimePicker
                value={expectedEndLocal}
                onChange={setExpectedEndLocal}
                placeholder="选择预计截止时间"
                defaultHour={18}
                popoverAlign="right"
                className="bg-[var(--bg)]"
              />
            </div>
          </div>
          <div className="grid grid-cols-2 gap-3">
            <div>
              <label className="block text-[12px] text-[var(--ink-soft)] mb-1">优先级</label>
              <FilterSelect
                value={effectivePriority}
                onChange={(value) => { setPriority(value as Priority); setPriorityManuallySet(true); }}
                options={(['P0', 'P1', 'P2', 'P3'] as Priority[]).map((p) => ({ value: p, label: p }))}
                showAllOption={false}
                className="w-full"
                labelClassName="max-w-[calc(100%-20px)]"
              />
            </div>
            <div>
              <label className="block text-[12px] text-[var(--ink-soft)] mb-1">执行预估工时（自动）</label>
              <div className="h-9 flex items-center px-3 rounded-lg border border-dashed border-[var(--line)] bg-[var(--bg-subtle)] text-[13px] text-[var(--ink-soft)] tabular-nums">
                {estimateHours > 0 ? formatWorkHours(estimateHours) : (startBeforeEnd ? '0h' : '请先选择有效起止时间')}
              </div>
              <p className="text-[10px] text-[var(--ink-muted)] mt-0.5">工作时段 9:00–12:00 + 13:00–18:00，跳过周末</p>
            </div>
          </div>
          {!startBeforeEnd && expectedStartLocal && expectedEndLocal && (
            <div className="rounded-lg border border-amber-200 bg-amber-50 p-2 text-[11px] text-amber-700">
              预计开始必须早于预计截止
            </div>
          )}
          {versionDeadline && (
            <p className="text-[10px] text-[var(--ink-muted)]">版本截止：{versionDeadline}</p>
          )}
          {isOverdueVersion && (
            <div className="rounded-lg border border-orange-200 bg-orange-50 p-3 space-y-2">
              <div className="flex items-center gap-1.5 text-[11px] text-orange-700">
                <AlertTriangle className="h-3.5 w-3.5" />
                任务预计截止超出版本截止日期（{versionDeadline}），请说明原因
              </div>
              <input value={overdueVersionReason} onChange={(e) => setOverdueVersionReason(e.target.value)} placeholder="超期原因（必填）" className="h-8 w-full rounded-md border border-orange-200 bg-white px-2 text-[12px] focus:border-orange-400 focus:outline-none" />
            </div>
          )}
          {versionTasks.length > 0 && (
            <div>
              <label className="block text-[12px] text-[var(--ink-soft)] mb-1">前置任务</label>
              <div className="space-y-1 max-h-28 overflow-y-auto border border-[var(--line)] rounded-lg p-2">
                {versionTasks.map((t) => (
                  <label key={t.id} className="flex items-center gap-2 text-[12px] text-[var(--ink)]">
                    <input type="checkbox" checked={predecessorIds.includes(t.id)} onChange={(e) => setPredecessorIds(e.target.checked ? [...predecessorIds, t.id] : predecessorIds.filter((x) => x !== t.id))} />
                    <span className="text-[var(--ink-muted)] font-mono">{t.taskNo}</span> {t.title}
                  </label>
                ))}
              </div>
            </div>
          )}
          <div>
            <label className="block text-[12px] text-[var(--ink-soft)] mb-1">描述</label>
            <textarea rows={3} value={description} onChange={(e) => setDescription(e.target.value)} className="w-full rounded-lg border border-[var(--line)] bg-[var(--bg)] px-3 py-2 text-[13px] focus:border-[var(--accent)] focus:outline-none resize-none" placeholder="任务描述（可选）" />
          </div>
          <div>
            <label className="block text-[12px] text-[var(--ink-soft)] mb-1">原型批注</label>
            <input value={prototypeNotes} onChange={(e) => setPrototypeNotes(e.target.value)} className="h-8 w-full rounded-lg border border-[var(--line)] bg-[var(--bg)] px-3 text-[13px] focus:border-[var(--accent)] focus:outline-none" placeholder="如 QY0007, QY0023" />
            <p className="mt-1 text-[11px] text-[var(--ink-muted)]">原型批注编号，逗号分隔（任务来自原型上的哪些标记）</p>
          </div>
        </div>
        <div className="flex justify-end gap-2 pt-4 border-t border-[var(--line)] mt-4">
          <button onClick={onClose} className="h-8 px-3 rounded-lg text-[12px] font-medium border border-[var(--line)] text-[var(--ink-soft)] hover:bg-[var(--bg-subtle)]">取消</button>
          <button onClick={handleSubmit} disabled={!canSubmit} className="h-8 px-4 rounded-lg text-[12px] font-medium bg-[var(--accent)] text-white hover:bg-[var(--accent-hover)] disabled:opacity-50">创建</button>
        </div>
      </div>
    </div>
  );
}
