'use client';
import { useState, useEffect, useMemo } from 'react';
import { Search, X } from 'lucide-react';
import type { Requirement, DictItem, SourceType, SourceTarget } from '@/lib/requirement';
import type { Priority } from '@/lib/derive';
import { filterRequirementProjectOptions, filterRequirementVersionOptions, filterSourceTargetsByKeyword, formatSourceTargetSelection, parseSourceTargetSelection, SOURCE_TYPE_LABEL, SOURCE_TARGET_LABEL } from '@/lib/requirement';

interface RequirementModalProps {
  open: boolean;
  initial?: Requirement | null;
  products: { id: string; name: string }[];
  projects: { id: string; name: string; productId: string }[];
  versions: { id: string; name: string; projectId: string }[];
  sourceTargets: SourceTarget[];
  types: DictItem[];
  platforms: DictItem[];
  requirements: Requirement[];
  currentUserName: string;
  onClose: () => void;
  onSubmit: (data: any) => void;
  onOpenDrawer: (type: 'source' | 'type' | 'platform') => void;
}

const PRIORITIES: Priority[] = ['P0', 'P1', 'P2', 'P3', 'P4'];
const SOURCE_TYPES: SourceType[] = ['customer', 'internal', 'operation', 'aftersale', 'market', 'competitor', 'management'];

const PRIORITY_COLORS: Record<Priority, string> = {
  P0: 'bg-red-500 text-white',
  P1: 'bg-orange-500 text-white',
  P2: 'bg-blue-500 text-white',
  P3: 'bg-zinc-500 text-white',
  P4: 'bg-zinc-400 text-white',
};

export function RequirementModal({
  open,
  initial,
  products,
  projects,
  versions,
  sourceTargets,
  types,
  platforms,
  requirements,
  currentUserName,
  onClose,
  onSubmit,
  onOpenDrawer,
}: RequirementModalProps) {
  const [title, setTitle] = useState('');
  const [description, setDescription] = useState('');
  const [sourceType, setSourceType] = useState<SourceType>('customer');
  const [selectedSourceTargets, setSelectedSourceTargets] = useState<string[]>([]);
  const [productId, setProductId] = useState('');
  const [projectId, setProjectId] = useState('');
  const [selectedPlatforms, setSelectedPlatforms] = useState<string[]>([]);
  const [typeId, setTypeId] = useState('');
  const [priority, setPriority] = useState<Priority>('P2');
  const [productOwner, setProductOwner] = useState('');
  const [parentId, setParentId] = useState('');
  const [versionId, setVersionId] = useState('');

  const [sourceTypeDropOpen, setSourceTypeDropOpen] = useState(false);
  const [sourceTargetDropOpen, setSourceTargetDropOpen] = useState(false);
  const [sourceTargetSearch, setSourceTargetSearch] = useState('');
  const [productDropOpen, setProductDropOpen] = useState(false);
  const [projectDropOpen, setProjectDropOpen] = useState(false);
  const [projectSearch, setProjectSearch] = useState('');
  const [versionDropOpen, setVersionDropOpen] = useState(false);
  const [versionSearch, setVersionSearch] = useState('');
  const [typeDropOpen, setTypeDropOpen] = useState(false);
  const [platformDropOpen, setPlatformDropOpen] = useState(false);

  const filteredProjects = useMemo(
    () => filterRequirementProjectOptions(projects, productId, projectSearch),
    [projects, productId, projectSearch],
  );

  const filteredVersions = useMemo(
    () => filterRequirementVersionOptions(versions, projectId, versionSearch),
    [versions, projectId, versionSearch],
  );

  useEffect(() => {
    if (initial) {
      setTitle(initial.title);
      setDescription(initial.description || '');
      setSourceType(initial.sourceType || 'customer');
      setSelectedSourceTargets(parseSourceTargetSelection(initial.sourceTarget));
      setSourceTypeDropOpen(false);
      setSourceTargetSearch('');
      setSourceTargetDropOpen(false);
      setProductDropOpen(false);
      setProjectSearch('');
      setProjectDropOpen(false);
      setVersionSearch('');
      setVersionDropOpen(false);
      setTypeDropOpen(false);
      setProductId(initial.productId || '');
      setProjectId(initial.projectId || '');
      setVersionId(initial.versionId || '');
      setSelectedPlatforms(initial.platforms || []);
      setTypeId(initial.typeId || '');
      setPriority(initial.priority || 'P2');
      setProductOwner(initial.productOwner || '');
      setParentId(initial.parentId || '');
    } else {
      setTitle('');
      setDescription('');
      setSourceType('customer');
      setSelectedSourceTargets([]);
      setSourceTypeDropOpen(false);
      setSourceTargetSearch('');
      setSourceTargetDropOpen(false);
      setProductDropOpen(false);
      setProjectSearch('');
      setProjectDropOpen(false);
      setVersionSearch('');
      setVersionDropOpen(false);
      setTypeDropOpen(false);
      setProductId('');
      setProjectId('');
      setVersionId('');
      setSelectedPlatforms([]);
      setTypeId('');
      setPriority('P2');
      setProductOwner('');
      setParentId('');
    }
  }, [initial, open]);

  if (!open) return null;

  const filteredTargets = filterSourceTargetsByKeyword(sourceTargets, sourceType, sourceTargetSearch);

  const toggleSourceTarget = (name: string) => {
    setSelectedSourceTargets((prev) =>
      prev.includes(name) ? prev.filter((item) => item !== name) : [...prev, name]
    );
  };

  const togglePlatform = (id: string) => {
    setSelectedPlatforms((prev) =>
      prev.includes(id) ? prev.filter((p) => p !== id) : [...prev, id]
    );
  };

  const handleSubmit = () => {
    if (!title.trim() || !productId || !projectId) return;
    onSubmit({
      title: title.trim(),
      description: description.trim(),
      sourceType,
      sourceTarget: formatSourceTargetSelection(selectedSourceTargets) || undefined,
      productId,
      projectId,
      versionId: versionId || undefined,
      platforms: selectedPlatforms,
      typeId: typeId || undefined,
      priority,
      effort: initial?.effort ?? 'M',
      status: initial?.status ?? 'pending_review',
      creator: initial?.creator || currentUserName || '系统',
      parentId: parentId || undefined,
    });
  };

  const sourceTargetDisplay =
    selectedSourceTargets.length > 0
      ? formatSourceTargetSelection(selectedSourceTargets)
      : '请选择';

  const productDisplay = productId
    ? products.find((product) => product.id === productId)?.name ?? '请选择产品'
    : '请选择产品';

  const projectDisplay = projectId
    ? projects.find((project) => project.id === projectId)?.name ?? '请选择项目'
    : productId
      ? '请选择项目'
      : '先选择产品';

  const versionDisplay = versionId
    ? versions.find((version) => version.id === versionId)?.name ?? '请选择版本'
    : projectId
      ? '请选择版本'
      : '先选择项目';

  const typeDisplay = typeId
    ? types.find((type) => type.id === typeId)?.name ?? '请选择类型'
    : '请选择类型';

  const platformDisplay =
    selectedPlatforms.length > 0
      ? platforms
          .filter((p) => selectedPlatforms.includes(p.id))
          .map((p) => p.name)
          .join(', ')
      : '请选择';

  return (
    <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/40" onClick={onClose}>
      <div
        className="w-full max-w-lg rounded-2xl bg-[var(--bg-card)] p-6 shadow-[var(--shadow-md)] max-h-[85vh] overflow-y-auto"
        onClick={(e) => e.stopPropagation()}
      >
        {/* Header */}
        <div className="flex items-center justify-between mb-5">
          <h2 className="text-[15px] font-semibold text-[var(--ink)]">
            {initial ? '编辑需求' : '新建需求'}
          </h2>
          <button
            onClick={onClose}
            className="p-1 rounded hover:bg-[var(--bg-subtle)] text-[var(--ink-muted)]"
          >
            <X className="h-4 w-4" />
          </button>
        </div>

        <div className="space-y-4">
          {/* 1. 需求概述 */}
          <div>
            <label className="text-[12px] font-medium text-[var(--ink-soft)] mb-1.5 block">
              需求概述 <span className="text-red-500">*</span>
            </label>
            <input
              type="text"
              value={title}
              onChange={(e) => setTitle(e.target.value)}
              placeholder="请输入需求标题"
              className="h-9 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] px-3 text-[13px] text-[var(--ink)] placeholder:text-[var(--ink-muted)] outline-none focus:border-[var(--accent)]"
            />
          </div>

          {/* 2. 需求描述 */}
          <div>
            <label className="text-[12px] font-medium text-[var(--ink-soft)] mb-1.5 block">
              需求描述
            </label>
            <textarea
              value={description}
              onChange={(e) => setDescription(e.target.value)}
              rows={3}
              placeholder="请输入需求描述"
              className="w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] px-3 py-2 text-[13px] text-[var(--ink)] placeholder:text-[var(--ink-muted)] outline-none focus:border-[var(--accent)] resize-none"
            />
          </div>

          {/* 3. 来源类型 + 来源对象 (2-column grid) */}
          <div className="grid grid-cols-2 gap-3">
            <div>
              <label className="text-[12px] font-medium text-[var(--ink-soft)] mb-1.5 block">
                来源类型
              </label>
              <div className="relative">
                <button
                  type="button"
                  onClick={() => setSourceTypeDropOpen(!sourceTypeDropOpen)}
                  className="h-9 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] px-3 text-[13px] text-left text-[var(--ink)] truncate"
                >
                  {SOURCE_TYPE_LABEL[sourceType]}
                </button>
                {sourceTypeDropOpen && (
                  <div className="absolute left-0 top-10 z-20 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] py-1 shadow-[var(--shadow-md)]">
                    {SOURCE_TYPES.map((item) => (
                      <button
                        key={item}
                        type="button"
                        onClick={() => {
                          setSourceType(item);
                          setSelectedSourceTargets([]);
                          setSourceTargetSearch('');
                          setSourceTargetDropOpen(false);
                          setSourceTypeDropOpen(false);
                        }}
                        className={`block w-full truncate px-3 py-1.5 text-left text-[13px] hover:bg-[var(--bg-subtle)] ${
                          sourceType === item ? 'font-medium text-[var(--accent)]' : 'text-[var(--ink)]'
                        }`}
                      >
                        {SOURCE_TYPE_LABEL[item]}
                      </button>
                    ))}
                  </div>
                )}
              </div>
            </div>
            <div>
              <div className="flex items-center justify-between mb-1.5">
                <label className="text-[12px] font-medium text-[var(--ink-soft)]">
                  {SOURCE_TARGET_LABEL[sourceType]}
                </label>
                <button
                  type="button"
                  onClick={() => onOpenDrawer('source')}
                  className="text-[11px] text-[var(--accent)] hover:underline"
                >
                  管理
                </button>
              </div>
              <div className="relative">
                <button
                  type="button"
                  onClick={() => setSourceTargetDropOpen(!sourceTargetDropOpen)}
                  className="h-9 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] px-3 text-[13px] text-left text-[var(--ink)] truncate"
                >
                  {sourceTargetDisplay}
                </button>
                {sourceTargetDropOpen && (
                  <div className="absolute left-0 top-10 z-20 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] shadow-[var(--shadow-md)]">
                    <div className="border-b border-[var(--line)] p-2">
                      <div className="relative">
                        <Search className="pointer-events-none absolute left-2.5 top-1/2 h-3.5 w-3.5 -translate-y-1/2 text-[var(--ink-muted)]" strokeWidth={2} />
                        <input
                          value={sourceTargetSearch}
                          onChange={(event) => setSourceTargetSearch(event.target.value)}
                          placeholder="搜索"
                          className="h-8 w-full rounded-lg border border-[var(--line)] bg-[var(--bg)] pl-8 pr-3 text-[12px] text-[var(--ink)] placeholder:text-[var(--ink-muted)] outline-none focus:border-[var(--accent)]"
                        />
                      </div>
                    </div>
                    <div className="max-h-40 overflow-y-auto py-1">
                      {filteredTargets.map((target) => (
                        <label
                          key={target.id}
                          className="flex items-center gap-2 px-3 py-1.5 hover:bg-[var(--bg-subtle)] cursor-pointer"
                        >
                          <input
                            type="checkbox"
                            checked={selectedSourceTargets.includes(target.name)}
                            onChange={() => toggleSourceTarget(target.name)}
                            className="h-3.5 w-3.5 rounded border-[var(--line)] accent-[var(--accent)]"
                          />
                          <span className="min-w-0 flex-1 truncate text-[13px] text-[var(--ink)]">{target.name}</span>
                        </label>
                      ))}
                      {filteredTargets.length === 0 && (
                        <div className="px-3 py-2 text-[12px] text-[var(--ink-muted)]">暂无匹配</div>
                      )}
                    </div>
                  </div>
                )}
              </div>
            </div>
          </div>

          {/* 4. 所属产品 → 项目 → 版本 */}
          <div className="grid grid-cols-3 gap-3">
            <div>
              <label className="text-[12px] font-medium text-[var(--ink-soft)] mb-1.5 block">
                所属产品 <span className="text-red-500">*</span>
              </label>
              <div className="relative">
                <button
                  type="button"
                  onClick={() => setProductDropOpen(!productDropOpen)}
                  className="h-9 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] px-3 text-[13px] text-left text-[var(--ink)] truncate"
                >
                  {productDisplay}
                </button>
                {productDropOpen && (
                  <div className="absolute left-0 top-10 z-20 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] py-1 shadow-[var(--shadow-md)]">
                    {products.map((product) => (
                      <button
                        key={product.id}
                        type="button"
                        onClick={() => {
                          setProductId(product.id);
                          setProjectId('');
                          setVersionId('');
                          setProjectSearch('');
                          setProjectDropOpen(false);
                          setVersionSearch('');
                          setVersionDropOpen(false);
                          setProductDropOpen(false);
                        }}
                        className={`block w-full truncate px-3 py-1.5 text-left text-[13px] hover:bg-[var(--bg-subtle)] ${
                          productId === product.id ? 'font-medium text-[var(--accent)]' : 'text-[var(--ink)]'
                        }`}
                      >
                        {product.name}
                      </button>
                    ))}
                    {products.length === 0 && (
                      <div className="px-3 py-2 text-[12px] text-[var(--ink-muted)]">暂无产品</div>
                    )}
                  </div>
                )}
              </div>
            </div>
            <div>
              <label className="text-[12px] font-medium text-[var(--ink-soft)] mb-1.5 block">
                所属项目 <span className="text-red-500">*</span>
              </label>
              <div className="relative">
                <button
                  type="button"
                  disabled={!productId}
                  onClick={() => productId && setProjectDropOpen(!projectDropOpen)}
                  className="h-9 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] px-3 text-[13px] text-left text-[var(--ink)] truncate disabled:cursor-not-allowed disabled:opacity-60"
                >
                  {projectDisplay}
                </button>
                {projectDropOpen && productId && (
                  <div className="absolute left-0 top-10 z-20 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] shadow-[var(--shadow-md)]">
                    <div className="border-b border-[var(--line)] p-2">
                      <div className="relative">
                        <Search className="pointer-events-none absolute left-2.5 top-1/2 h-3.5 w-3.5 -translate-y-1/2 text-[var(--ink-muted)]" strokeWidth={2} />
                        <input
                          value={projectSearch}
                          onChange={(event) => setProjectSearch(event.target.value)}
                          placeholder="搜索项目"
                          className="h-8 w-full rounded-lg border border-[var(--line)] bg-[var(--bg)] pl-8 pr-3 text-[12px] text-[var(--ink)] placeholder:text-[var(--ink-muted)] outline-none focus:border-[var(--accent)]"
                        />
                      </div>
                    </div>
                    <div className="max-h-40 overflow-y-auto py-1">
                      {filteredProjects.map((project) => (
                        <button
                          key={project.id}
                          type="button"
                          onClick={() => {
                            setProjectId(project.id);
                            setVersionId('');
                            setProjectSearch('');
                            setProjectDropOpen(false);
                            setVersionSearch('');
                            setVersionDropOpen(false);
                          }}
                          className="block w-full truncate px-3 py-1.5 text-left text-[13px] text-[var(--ink)] hover:bg-[var(--bg-subtle)]"
                        >
                          {project.name}
                        </button>
                      ))}
                      {filteredProjects.length === 0 && (
                        <div className="px-3 py-2 text-[12px] text-[var(--ink-muted)]">暂无匹配</div>
                      )}
                    </div>
                  </div>
                )}
              </div>
            </div>
            <div>
              <label className="text-[12px] font-medium text-[var(--ink-soft)] mb-1.5 block">
                所属版本
              </label>
              <div className="relative">
                <button
                  type="button"
                  disabled={!projectId}
                  onClick={() => projectId && setVersionDropOpen(!versionDropOpen)}
                  className="h-9 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] px-3 text-[13px] text-left text-[var(--ink)] truncate disabled:cursor-not-allowed disabled:opacity-60"
                >
                  {versionDisplay}
                </button>
                {versionDropOpen && projectId && (
                  <div className="absolute left-0 top-10 z-20 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] shadow-[var(--shadow-md)]">
                    <div className="border-b border-[var(--line)] p-2">
                      <div className="relative">
                        <Search className="pointer-events-none absolute left-2.5 top-1/2 h-3.5 w-3.5 -translate-y-1/2 text-[var(--ink-muted)]" strokeWidth={2} />
                        <input
                          value={versionSearch}
                          onChange={(event) => setVersionSearch(event.target.value)}
                          placeholder="搜索版本"
                          className="h-8 w-full rounded-lg border border-[var(--line)] bg-[var(--bg)] pl-8 pr-3 text-[12px] text-[var(--ink)] placeholder:text-[var(--ink-muted)] outline-none focus:border-[var(--accent)]"
                        />
                      </div>
                    </div>
                    <div className="max-h-40 overflow-y-auto py-1">
                      {filteredVersions.map((version) => (
                        <button
                          key={version.id}
                          type="button"
                          onClick={() => {
                            setVersionId(version.id);
                            setVersionSearch('');
                            setVersionDropOpen(false);
                          }}
                          className="block w-full truncate px-3 py-1.5 text-left text-[13px] text-[var(--ink)] hover:bg-[var(--bg-subtle)]"
                        >
                          {version.name}
                        </button>
                      ))}
                      {filteredVersions.length === 0 && (
                        <div className="px-3 py-2 text-[12px] text-[var(--ink-muted)]">暂无匹配</div>
                      )}
                    </div>
                  </div>
                )}
              </div>
            </div>
          </div>

          {/* 5. 支持端 (multi-select) */}
          <div>
            <div className="flex items-center justify-between mb-1.5">
              <label className="text-[12px] font-medium text-[var(--ink-soft)]">支持端</label>
              <button
                type="button"
                onClick={() => onOpenDrawer('platform')}
                className="text-[11px] text-[var(--accent)] hover:underline"
              >
                管理
              </button>
            </div>
            <div className="relative">
              <button
                type="button"
                onClick={() => setPlatformDropOpen(!platformDropOpen)}
                className="h-9 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] px-3 text-[13px] text-left text-[var(--ink)] truncate"
              >
                {platformDisplay}
              </button>
              {platformDropOpen && (
                <div className="absolute top-10 left-0 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] shadow-[var(--shadow-md)] z-10 max-h-40 overflow-y-auto py-1">
                  {platforms.map((p) => (
                    <label
                      key={p.id}
                      className="flex items-center gap-2 px-3 py-1.5 hover:bg-[var(--bg-subtle)] cursor-pointer"
                    >
                      <input
                        type="checkbox"
                        checked={selectedPlatforms.includes(p.id)}
                        onChange={() => togglePlatform(p.id)}
                        className="h-3.5 w-3.5 rounded border-[var(--line)] accent-[var(--accent)]"
                      />
                      <span className="text-[13px] text-[var(--ink)]">{p.name}</span>
                    </label>
                  ))}
                  {platforms.length === 0 && (
                    <div className="px-3 py-2 text-[12px] text-[var(--ink-muted)]">暂无数据</div>
                  )}
                </div>
              )}
            </div>
          </div>

          {/* 6. 需求类型 */}
          <div>
            <div className="flex items-center justify-between mb-1.5">
              <label className="text-[12px] font-medium text-[var(--ink-soft)]">需求类型</label>
              <button
                type="button"
                onClick={() => onOpenDrawer('type')}
                className="text-[11px] text-[var(--accent)] hover:underline"
              >
                管理
              </button>
            </div>
            <div className="relative">
              <button
                type="button"
                onClick={() => setTypeDropOpen(!typeDropOpen)}
                className="h-9 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] px-3 text-[13px] text-left text-[var(--ink)] truncate"
              >
                {typeDisplay}
              </button>
              {typeDropOpen && (
                <div className="absolute left-0 top-10 z-20 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] py-1 shadow-[var(--shadow-md)]">
                  {types.map((type) => (
                    <button
                      key={type.id}
                      type="button"
                      onClick={() => {
                        setTypeId(type.id);
                        setTypeDropOpen(false);
                      }}
                      className={`block w-full truncate px-3 py-1.5 text-left text-[13px] hover:bg-[var(--bg-subtle)] ${
                        typeId === type.id ? 'font-medium text-[var(--accent)]' : 'text-[var(--ink)]'
                      }`}
                    >
                      {type.name}
                    </button>
                  ))}
                  {types.length === 0 && (
                    <div className="px-3 py-2 text-[12px] text-[var(--ink-muted)]">暂无类型</div>
                  )}
                </div>
              )}
            </div>
          </div>

          {/* 7. 优先级 (button group) */}
          <div>
            <label className="text-[12px] font-medium text-[var(--ink-soft)] mb-1.5 block">
              优先级
            </label>
            <div className="flex gap-2">
              {PRIORITIES.map((p) => (
                <button
                  key={p}
                  type="button"
                  onClick={() => setPriority(p)}
                  className={`h-8 px-3 rounded-lg text-[12px] font-medium transition-colors ${
                    priority === p
                      ? PRIORITY_COLORS[p]
                      : 'border border-[var(--line)] text-[var(--ink-soft)] hover:bg-[var(--bg-subtle)]'
                  }`}
                >
                  {p}
                </button>
              ))}
            </div>
          </div>

          {/* 10. 关联父需求 */}
          <div>
            <label className="text-[12px] font-medium text-[var(--ink-soft)] mb-1.5 block">
              关联父需求
            </label>
            <select
              value={parentId}
              onChange={(e) => setParentId(e.target.value)}
              className="h-9 w-full rounded-lg border border-[var(--line)] bg-[var(--bg-card)] px-3 text-[13px] text-[var(--ink)] outline-none focus:border-[var(--accent)]"
            >
              <option value="">无</option>
              {requirements
                .filter((r) => r.id !== initial?.id)
                .map((r) => (
                  <option key={r.id} value={r.id}>
                    {r.code} - {r.title}
                  </option>
                ))}
            </select>
          </div>
        </div>

        {/* Footer */}
        <div className="flex items-center justify-end gap-3 mt-6 pt-4 border-t border-[var(--line)]">
          <button
            type="button"
            onClick={onClose}
            className="h-9 px-4 rounded-lg border border-[var(--line)] text-[13px] font-medium text-[var(--ink-soft)] hover:bg-[var(--bg-subtle)] transition-colors"
          >
            取消
          </button>
          <button
            type="button"
            onClick={handleSubmit}
            className="h-9 px-4 rounded-lg bg-[var(--accent)] text-white text-[13px] font-medium hover:opacity-90 transition-opacity"
          >
            {initial ? '保存' : '创建'}
          </button>
        </div>
      </div>
    </div>
  );
}