// 审批分类通用页面 — 资源申请/应用申请/权限审批三个子页面共用
import { useState, useEffect, useCallback } from 'react';
import { useTranslation } from 'react-i18next';
import { Button } from '@/components/ui/button';
import { Input } from '@/components/ui/input';
import { Badge } from '@/components/ui/badge';
import { Label } from '@/components/ui/label';
import {
  Dialog, DialogContent, DialogDescription, DialogHeader, DialogTitle,
} from '@/components/ui/dialog';
import {
  Table, TableBody, TableCell, TableHead, TableHeader, TableRow,
} from '@/components/ui/table';
import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select';
import { Plus, Search, RefreshCw, Clock, CheckCircle, XCircle, FileText, Eye, Check, XIcon, User, ChevronRight, Play } from 'lucide-react';
import { approvalApi } from '@/api';
import { toast } from 'sonner';
import { PageShell } from '@/components/layout/PageShell';
import { ContentPanel } from '@/components/layout/ContentPanel';
import { PageEmpty } from '@/components/layout/PageEmpty';
import type { JsonData } from '@/types/common';

export interface FormField {
  key: string; label: string; type: 'text' | 'number' | 'select' | 'textarea';
  options?: string[]; placeholder?: string; defaultValue?: string | number; required?: boolean;
}

interface Props {
  category: 'resource' | 'app' | 'permission';
  title: string; description: string; fields: FormField[]; templateCode: string;
}

interface StepItem {
  id: number; step: number; step_type?: string; approver: number; status: string; comment: string;
  approved_at: string | null; approver_user?: { username?: string; real_name?: string };
}

interface ProcessItem {
  id: number; title: string; status: string; form_data: string; created_at: string;
  applicant: number; applicant_user?: { username?: string; real_name?: string };
  template?: { name?: string }; current_step?: number; total_steps?: number;
  steps?: StepItem[];
}

const statusBadge = (status: string, t: (k: string) => string) => {
  switch (status) {
    case 'approved': return <Badge className="bg-emerald-500/20 dg-text-green border-emerald-500/30"><CheckCircle className="h-3 w-3 mr-1" />{t('approval.status.approved')}</Badge>;
    case 'rejected': return <Badge className="bg-red-500/20 dg-text-red border-red-500/30"><XCircle className="h-3 w-3 mr-1" />{t('approval.status.rejected')}</Badge>;
    default: return <Badge className="bg-amber-500/20 dg-text-yellow border-amber-500/30"><Clock className="h-3 w-3 mr-1" />{t('approval.status.pending')}</Badge>;
  }
};

function parseFormData(data: string): Record<string, string> {
  try { return JSON.parse(data) || {}; } catch { return {}; }
}

function getApplicant(p: JsonData): string {
  const u = p?.applicant_user;
  return u ? (u.real_name || u.username || `#${p.applicant}`) : (p?.applicant ? `#${p.applicant}` : '--');
}

function getCurrentApprover(p: ProcessItem, t: (k: string) => string): string {
  if (p.status !== 'pending') return '--';
  const steps = p.steps || [];
  if (steps.length === 0) return t('approval.detail.adminPending');
  const cs = steps.find(s => s.step === p.current_step && s.status === 'pending');
  if (!cs) return t('approval.detail.adminPending');
  if (cs.approver_user) return cs.approver_user.real_name || cs.approver_user.username || `#${cs.approver}`;
  return t('approval.detail.admin');
}

export function ApprovalCategoryPage({ category, title, description, fields, templateCode }: Props) {
  const { t } = useTranslation();
  const [processes, setProcesses] = useState<ProcessItem[]>([]);
  const [loading, setLoading] = useState(true);
  const [keyword, setKeyword] = useState('');
  const [statusFilter, setStatusFilter] = useState('');
  const [dialogOpen, setDialogOpen] = useState(false);
  const [submitting, setSubmitting] = useState(false);
  const [templateId, setTemplateId] = useState<number | null>(null);
  const [formData, setFormData] = useState<Record<string, string>>({});
  const [detailItem, setDetailItem] = useState<ProcessItem | null>(null);
  const [acting, setActing] = useState(false);

  const fetchProcesses = useCallback(async () => {
    setLoading(true);
    try {
      const params: JsonData = { page_size: '100' };
      if (category) params.category = category;
      if (statusFilter) params.status = statusFilter;
      const resp = (await approvalApi.getProcesses(params)) as JsonData;
      setProcesses(resp?.list ?? resp?.data?.list ?? []);
    } catch { setProcesses([]); }
    finally { setLoading(false); }
  }, [category, statusFilter]);

  const fetchTemplateId = useCallback(async () => {
    try {
      const resp = (await approvalApi.getTemplates({ type: templateCode })) as JsonData;
      const list = resp?.list ?? resp?.data?.list ?? [];
      if (list.length > 0) setTemplateId(list[0].id);
    } catch {
      // 模板缺失时保留空状态，由创建流程提示用户。// Logan.Li
    }
  }, [templateCode]);

  useEffect(() => { fetchProcesses(); }, [fetchProcesses]);
  useEffect(() => { fetchTemplateId(); }, [fetchTemplateId]);

  const handleCreate = async () => {
    if (!templateId) { toast.error(t('approval.msg.templateNotLoaded')); return; }
    for (const f of fields) { if (f.required && !formData[f.key]) { toast.error(t('approval.msg.pleaseFill', { label: f.label })); return; } }
    setSubmitting(true);
    try {
      const firstVal = formData[fields[0]?.key] || '';
      const secondVal = fields[1] ? formData[fields[1].key] || '' : '';
      await approvalApi.createProcess({
        template_id: templateId,
        title: `${title} - ${firstVal}${secondVal ? ' / ' + secondVal : ''}`,
        form_data: JSON.stringify(formData),
      });
      toast.success(t('approval.msg.submitSuccess'));
      setDialogOpen(false); setFormData({}); fetchProcesses();
    } catch (err) { toast.error(err?.message || t('approval.msg.submitFailed')); }
    finally { setSubmitting(false); }
  };

  const openCreateDialog = () => {
    const init: Record<string, string> = {};
    fields.forEach((f) => { init[f.key] = f.defaultValue?.toString() || ''; });
    setFormData(init); setDialogOpen(true);
  };

  const handleApprove = async (id: number) => {
    setActing(true);
    try { await approvalApi.approveProcess(id); toast.success(t('approval.msg.approveSuccess')); fetchProcesses(); }
    catch (err) { toast.error(err?.response?.data?.message || t('approval.msg.approveFailed')); }
    finally { setActing(false); }
  };

  const handleReject = async (id: number) => {
    setActing(true);
    try { await approvalApi.rejectProcess(id, t('approval.flow.rejectTitle')); toast.success(t('approval.msg.rejectSuccess')); fetchProcesses(); }
    catch (err) { toast.error(err?.response?.data?.message || t('common.operationFailed')); }
    finally { setActing(false); }
  };

  const openDetail = async (p: ProcessItem) => {
    // Load full detail including steps
    try {
      const resp: JsonData = await approvalApi.getProcesses({ page_size: 200 } as JsonData);
      const list = resp?.list ?? resp?.data?.list ?? [];
      const full = list.find((x: JsonData) => x.id === p.id);
      setDetailItem(full || p);
    } catch { setDetailItem(p); }
  };

  const filtered = processes.filter((p) => !keyword || (p.title || '').toLowerCase().includes(keyword.toLowerCase()));

  // 工具栏：搜索 + 状态筛选 // Logan.Li
  const toolbar = (
    <div className="flex items-center gap-3 flex-wrap">
      <div className="relative w-64">
        <Search className="absolute left-3 top-1/2 -translate-y-1/2 h-4 w-4 dg-text-muted" />
        <Input placeholder={t('approval.flow.searchRequest')} value={keyword} onChange={(e) => setKeyword(e.target.value)}
          className="pl-9 h-9 dg-input" />
      </div>
      <Select value={statusFilter} onValueChange={setStatusFilter}>
        <SelectTrigger className="w-32 h-9 dg-input">
          <SelectValue placeholder={t('common.all')} />
        </SelectTrigger>
        <SelectContent>
          <SelectItem value="all">{t('common.all')}</SelectItem>
          <SelectItem value="pending">{t('approval.status.pending')}</SelectItem>
          <SelectItem value="approved">{t('approval.status.approved')}</SelectItem>
          <SelectItem value="rejected">{t('approval.status.rejected')}</SelectItem>
        </SelectContent>
      </Select>
      <Button variant="outline" size="sm" className="dg-btn-secondary" onClick={fetchProcesses}>
        <RefreshCw className="h-4 w-4 mr-2" />{t('common.refresh')}
      </Button>
    </div>
  );

  return (
    <>
      <PageShell
        variant="list"
        title={title}
        subtitle={description}
        icon={<FileText className="h-5 w-5" />}
        toolbar={toolbar}
        loading={loading}
        actions={(
          <Button onClick={openCreateDialog} className="dg-btn-primary">
            <Plus className="h-4 w-4 mr-2" />{t('approval.newRequest')}
          </Button>
        )}
      >
        <ContentPanel noPadding>
          {filtered.length === 0 ? (
            <PageEmpty
              icon={<FileText className="h-10 w-10" />}
              title={t('approval.noRecords')}
              action={(
                <Button variant="link" onClick={openCreateDialog}>{t('approval.applyNow')}</Button>
              )}
            />
          ) : (
            <Table>
              <TableHeader>
                <TableRow className="border-[var(--dg-border)] hover:bg-transparent">
                  <TableHead className="text-[var(--dg-text-secondary)]">{t('approval.col.submitTime')}</TableHead>
                  <TableHead className="text-[var(--dg-text-secondary)]">{t('approval.col.submitAccount')}</TableHead>
                  <TableHead className="text-[var(--dg-text-secondary)]">{t('approval.col.currentApprover')}</TableHead>
                  <TableHead className="text-[var(--dg-text-secondary)]">{t('approval.col.status')}</TableHead>
                  <TableHead className="text-[var(--dg-text-secondary)] w-28">{t('approval.col.actions')}</TableHead>
                </TableRow>
              </TableHeader>
              <TableBody>
                {filtered.map((p) => (
                  <TableRow key={p.id} className="border-[var(--dg-border)] hover:bg-[var(--dg-bg-hover)]">
                    <TableCell className="text-[var(--dg-text-muted)] text-sm whitespace-nowrap">
                      {p.created_at ? new Date(p.created_at).toLocaleString('zh-CN') : '--'}
                    </TableCell>
                    <TableCell className="text-[var(--dg-text-primary)]">{getApplicant(p)}</TableCell>
                    <TableCell className="text-[var(--dg-text-muted)] text-sm">{getCurrentApprover(p, t)}</TableCell>
                    <TableCell>{statusBadge(p.status, t)}</TableCell>
                    <TableCell>
                      <div className="flex items-center gap-1">
                        {p.status === 'pending' ? (
                          <>
                            <Button variant="ghost" size="sm" className="h-8 dg-text-red hover:bg-red-500/10" onClick={() => handleReject(p.id)} disabled={acting}>
                              <XIcon className="h-3.5 w-3.5 mr-1" />{t('common.reject')}
                            </Button>
                            <Button variant="ghost" size="sm" className="h-8 dg-text-green hover:bg-emerald-500/10" onClick={() => handleApprove(p.id)} disabled={acting}>
                              <Check className="h-3.5 w-3.5 mr-1" />{t('common.approve')}
                            </Button>
                          </>
                        ) : (
                          <Button variant="ghost" size="sm" className="h-8 text-[var(--dg-text-muted)] hover:text-[var(--dg-text-primary)]" onClick={() => openDetail(p)}>
                            <Eye className="h-3.5 w-3.5 mr-1" />{t('common.detail')}
                          </Button>
                        )}
                      </div>
                    </TableCell>
                  </TableRow>
                ))}
              </TableBody>
            </Table>
          )}
        </ContentPanel>
      </PageShell>

      {/* Create Dialog */}
      <Dialog open={dialogOpen} onOpenChange={setDialogOpen}>
        <DialogContent className="bg-[var(--dg-bg-secondary)] border-[var(--dg-border)] max-w-lg max-h-[85vh] overflow-y-auto">
          <DialogHeader>
            <DialogTitle className="text-[var(--dg-text-primary)]">{t('approval.newRequest')} {title}</DialogTitle>
            <DialogDescription className="text-[var(--dg-text-secondary)]">{description}</DialogDescription>
          </DialogHeader>
          <div className="space-y-4 py-2">
            {fields.map((field) => (
              <div key={field.key} className="space-y-1.5">
                <Label className="text-[var(--dg-text-primary)] text-sm">{field.label}{field.required && <span className="dg-text-red ml-0.5">*</span>}</Label>
                {field.type === 'select' ? (
                  <Select value={formData[field.key] || ''} onValueChange={(v) => setFormData((prev) => ({ ...prev, [field.key]: v }))}>
                    <SelectTrigger className="bg-[var(--dg-bg-tertiary)] border-[var(--dg-border)]"><SelectValue placeholder={field.placeholder || `${t('approval.editor.pleaseSelect')}${field.label}`} /></SelectTrigger>
                    <SelectContent>{(field.options || []).map((opt) => (<SelectItem key={opt} value={opt}>{opt}</SelectItem>))}</SelectContent>
                  </Select>
                ) : field.type === 'textarea' ? (
                  <textarea value={formData[field.key] || ''} onChange={(e) => setFormData((prev) => ({ ...prev, [field.key]: e.target.value }))}
                    placeholder={field.placeholder} rows={3}
                    className="w-full rounded-md bg-[var(--dg-bg-tertiary)] border border-[var(--dg-border)] text-[var(--dg-text-primary)] px-3 py-2 text-sm resize-none focus:outline-none focus:border-[var(--dg-blue)]" />
                ) : (
                  <Input type={field.type} value={formData[field.key] || ''} onChange={(e) => setFormData((prev) => ({ ...prev, [field.key]: e.target.value }))}
                    placeholder={field.placeholder} className="bg-[var(--dg-bg-tertiary)] border-[var(--dg-border)]" />
                )}
              </div>
            ))}
          </div>
          <div className="flex justify-end gap-3 pt-2">
            <Button variant="outline" className="border-[var(--dg-border)]" onClick={() => setDialogOpen(false)}>{t('common.cancel')}</Button>
            <Button onClick={handleCreate} disabled={submitting} className="dg-btn-primary">
              {submitting ? t('approval.submitting') : t('approval.submitRequest')}
            </Button>
          </div>
        </DialogContent>
      </Dialog>

      {/* Detail Dialog — operation timeline */}
      <DetailTimelineDialog item={detailItem} onClose={() => setDetailItem(null)} fields={fields} onStatusChange={fetchProcesses} />
    </>
  );
}

/* ------------------------------------------------------------------ */
/*  DetailTimelineDialog — 操作时间线                                   */
/* ------------------------------------------------------------------ */

function DetailTimelineDialog({ item, onClose, fields, onStatusChange }: {
  item: ProcessItem | null; onClose: () => void; fields: FormField[]; onStatusChange: () => void;
}) {
  const { t } = useTranslation();
  const [acting, setActing] = useState(false);
  if (!item) return null;

  const timeStr = (tm: string | null) => {
    if (!tm) return '';
    return new Date(tm).toLocaleString('zh-CN');
  };

  const steps = item.steps || [];

  const handleApprove = async () => {
    setActing(true);
    try { await approvalApi.approveProcess(item.id); toast.success(t('approval.msg.approveSuccess')); onStatusChange(); onClose(); }
    catch (err) { toast.error(err?.response?.data?.message || t('approval.msg.approveFailed')); }
    finally { setActing(false); }
  };

  const handleReject = async () => {
    setActing(true);
    try { await approvalApi.rejectProcess(item.id, t('approval.flow.rejectTitle')); toast.success(t('approval.msg.rejectSuccess')); onStatusChange(); onClose(); }
    catch (err) { toast.error(err?.response?.data?.message || t('common.operationFailed')); }
    finally { setActing(false); }
  };

  const stepStatusLabel = (s: StepItem) => {
    if (s.status === 'approved') return t('approval.status.passed');
    if (s.status === 'rejected') return t('common.reject');
    if (s.status === 'pending' && s.step === item.current_step) return t('approval.status.waiting');
    if (s.status === 'pending') return t('approval.status.notStarted');
    return s.status;
  };

  const stepStatusColor = (s: StepItem) => {
    if (s.status === 'approved') return 'dg-text-green';
    if (s.status === 'rejected') return 'dg-text-red';
    if (s.step === item.current_step) return 'dg-text-blue';
    return 'text-[var(--dg-text-muted)]';
  };

  const approverName = (s: StepItem) => {
    if (s.approver_user) return s.approver_user.real_name || s.approver_user.username || `#${s.approver}`;
    return t('approval.detail.admin');
  };

  return (
    <Dialog open={!!item} onOpenChange={(v) => { if (!v) onClose(); }}>
      <DialogContent className="bg-[var(--dg-bg-secondary)] border-[var(--dg-border)] max-w-lg max-h-[85vh] overflow-y-auto">
        <DialogHeader>
          <DialogTitle className="text-[var(--dg-text-primary)]">{t('approval.detail.title')}</DialogTitle>
          <DialogDescription className="text-[var(--dg-text-secondary)]">{item.title}</DialogDescription>
        </DialogHeader>

        <div className="space-y-4 py-2">
          {/* Status + Meta */}
          <div className="flex items-center gap-3">
            <span className="text-sm text-[var(--dg-text-muted)]">{t('approval.detail.statusLabel')}</span>
            {statusBadge(item.status, t)}
            {item.status === 'pending' && (
              <span className="text-xs text-[var(--dg-text-muted)]">
                {t('approval.detail.stepProgress', { current: item.current_step, total: item.total_steps })}
              </span>
            )}
          </div>

          {/* Operation Timeline */}
          <div className="border-t border-[var(--dg-border)] pt-4">
            <h4 className="text-sm font-medium text-[var(--dg-text-primary)] mb-4">{t('approval.detail.operationTimeline')}</h4>
            <div className="space-y-0">
              {/* 1. Submit node */}
              <div className="flex gap-3">
                <div className="flex flex-col items-center">
                  <div className="w-7 h-7 rounded-full bg-blue-500/20 flex items-center justify-center"><User className="w-3.5 h-3.5 dg-text-blue" /></div>
                  <div className="w-0.5 flex-1 bg-[var(--dg-border)] my-1" />
                </div>
                <div className="flex-1 pb-4">
                  <div className="flex items-center gap-2">
                    <span className="text-sm font-medium text-[var(--dg-text-primary)]">{t('approval.detail.submitNode')}</span>
                    <span className="text-xs text-[var(--dg-text-muted)]">·</span>
                    <span className="text-xs text-[var(--dg-text-secondary)]">{getApplicant(item)}</span>
                    <span className="text-xs text-[var(--dg-text-muted)]">·</span>
                    <span className="text-xs text-[var(--dg-text-muted)]">{timeStr(item.created_at)}</span>
                  </div>
                  {/* Form data summary */}
                  <div className="mt-1 flex flex-wrap gap-2">
                    {(() => {
                      const data = parseFormData(item.form_data || '{}');
                      return fields.slice(0, 4).map((f) => {
                        const val = data[f.key];
                        if (!val) return null;
                        return (
                          <span key={f.key} className="text-[11px] px-1.5 py-0.5 rounded bg-[var(--dg-bg-tertiary)] text-[var(--dg-text-muted)]">
                            {f.label}: <span className="text-[var(--dg-text-secondary)]">{val}</span>
                          </span>
                        );
                      });
                    })()}
                  </div>
                </div>
              </div>

              {/* 2. Approval / Execution steps */}
              {steps.map((s, i) => {
                const isLast = i === steps.length - 1;
                const isExecute = s.step_type === 'execute';
                const stepLabel = isExecute ? t('approval.step.executeShort') : t('approval.step.auditShort');
                const iconColor = s.status === 'approved' ? 'bg-emerald-500/20'
                  : s.status === 'rejected' ? 'bg-red-500/20'
                  : 'bg-[var(--dg-bg-tertiary)]';
                return (
                  <div key={s.id} className="flex gap-3">
                    <div className="flex flex-col items-center">
                      <div className={`w-7 h-7 rounded-full flex items-center justify-center ${iconColor}`}>
                        {s.status === 'approved' ? <Check className="w-3.5 h-3.5 dg-text-green" />
                          : s.status === 'rejected' ? <XIcon className="w-3.5 h-3.5 dg-text-red" />
                            : isExecute
                              ? <Play className={`w-3.5 h-3.5 ${s.step === item.current_step ? 'dg-text-green' : 'text-[var(--dg-text-muted)]'}`} />
                              : <ChevronRight className={`w-3.5 h-3.5 ${s.step === item.current_step ? 'dg-text-blue' : 'text-[var(--dg-text-muted)]'}`} />}
                      </div>
                      {!isLast && <div className="w-0.5 flex-1 bg-[var(--dg-border)] my-1" />}
                    </div>
                    <div className={`flex-1 ${!isLast ? 'pb-4' : ''}`}>
                      <div className="flex items-center gap-2 flex-wrap">
                        <span className="text-sm font-medium text-[var(--dg-text-primary)]">{stepLabel}</span>
                        {s.approver_user && (
                          <>
                            <span className="text-xs text-[var(--dg-text-muted)]">·</span>
                            <span className="text-xs text-[var(--dg-text-secondary)]">{t('approval.detail.assignee')}: {approverName(s)}</span>
                          </>
                        )}
                        {s.approved_at && (
                          <>
                            <span className="text-xs text-[var(--dg-text-muted)]">·</span>
                            <span className={`text-xs ${stepStatusColor(s)}`}>
                              {approverName(s)} · {stepStatusLabel(s)} · {timeStr(s.approved_at)}
                            </span>
                          </>
                        )}
                        {!s.approved_at && (
                          <>
                            <span className="text-xs text-[var(--dg-text-muted)]">·</span>
                            <span className={`text-xs ${stepStatusColor(s)}`}>{stepStatusLabel(s)}</span>
                          </>
                        )}
                      </div>
                      {s.comment && s.comment !== s.status && s.comment !== 'pending' && (
                        <p className="text-xs text-[var(--dg-text-muted)] mt-1 ml-0">{s.comment}</p>
                      )}
                    </div>
                  </div>
                );
              })}
            </div>
          </div>

          {/* Full form data */}
          <div className="border-t border-[var(--dg-border)] pt-4">
            <h4 className="text-sm font-medium text-[var(--dg-text-primary)] mb-2">{t('approval.detail.requestContent')}</h4>
            <div className="space-y-2">
              {(() => {
                const data = parseFormData(item.form_data || '{}');
                return fields.map((f) => {
                  const val = data[f.key];
                  return (
                    <div key={f.key} className="grid grid-cols-3 gap-2 text-sm">
                      <span className="text-[var(--dg-text-muted)]">{f.label}：</span>
                      <span className="text-[var(--dg-text-primary)] col-span-2">{val ?? '--'}</span>
                    </div>
                  );
                });
              })()}
            </div>
          </div>
        </div>

        <div className="flex justify-end gap-3 pt-2">
          {item.status === 'pending' && (
            <>
              <Button variant="outline" className="border-red-500/30 dg-text-red hover:bg-red-500/10" onClick={handleReject} disabled={acting}>
                <XIcon className="h-4 w-4 mr-1.5" />{t('common.reject')}
              </Button>
              <Button className="bg-emerald-600 hover:bg-emerald-700" onClick={handleApprove} disabled={acting}>
                <Check className="h-4 w-4 mr-1.5" />{t('common.approve')}
              </Button>
            </>
          )}
          <Button variant="outline" className="border-[var(--dg-border)]" onClick={onClose}>{t('common.close')}</Button>
        </div>
      </DialogContent>
    </Dialog>
  );
}