// Panel 3 cho 3-panel layout — gom WorkflowSummaryCard (timeline policy) +
// approval history (ai/khi/quyết định gì) + ContractChangelogsTab (mọi thay
// đổi header/detail/comment/attachment/transition) vào 1 stack. Dùng cho cả
// MyContracts 3-panel và ContractDetailPage fullpage.
import { ArrowRight, Clock, History, Users2 } from 'lucide-react'
import { useQuery } from '@tanstack/react-query'
import { PhaseBadge } from '@/components/PhaseBadge'
import { WorkflowSummaryCard } from '@/components/WorkflowSummaryCard'
import { ContractChangelogsTab } from '@/components/contracts/ContractChangelogsTab'
import { api } from '@/lib/api'
import { cn } from '@/lib/cn'
import {
  ApprovalStage,
  ContractPhaseColor,
  ContractPhaseLabel,
  type ContractDepartmentApproval,
  type ContractDetail,
} from '@/types/contracts'

const fmt = (s: string) => new Date(s).toLocaleString('vi-VN')
const fmtTime = (iso: string) =>
  new Date(iso).toLocaleString('vi-VN', { day: '2-digit', month: '2-digit', hour: '2-digit', minute: '2-digit' })

export function WorkflowHistoryPanel({ contract: c }: { contract: ContractDetail }) {
  const { data: deptApprovals = [] } = useQuery<ContractDepartmentApproval[]>({
    queryKey: ['contract-dept-approvals', c.id],
    queryFn: async () => (await api.get(`/contracts/${c.id}/department-approvals`)).data,
  })

  return (
    <div className="space-y-4">
      {c.workflow && <WorkflowSummaryCard workflow={c.workflow} currentPhase={c.phase} />}

      {deptApprovals.length > 0 && (
        <DeptApprovalsSection rows={deptApprovals} currentPhase={c.phase} />
      )}

      <section className="rounded-xl border border-slate-200 bg-white p-5 shadow-sm">
        <h2 className="mb-3 flex items-center gap-2 text-sm font-semibold text-slate-700">
          <Clock className="h-4 w-4" />
          Lịch sử duyệt ({c.approvals.length})
        </h2>
        <ol className="space-y-3">
          {c.approvals.length === 0 && <li className="text-sm text-slate-400">Chưa có lịch sử.</li>}
          {c.approvals.map(a => (
            <li key={a.id} className="flex gap-3">
              <div className="mt-1 h-2 w-2 rounded-full bg-brand-500" />
              <div className="flex-1 space-y-0.5 text-sm">
                <div className="flex items-center gap-1">
                  <PhaseBadge phase={a.fromPhase} className="text-[10px]" />
                  <ArrowRight className="h-3 w-3 text-slate-400" />
                  <PhaseBadge phase={a.toPhase} className="text-[10px]" />
                </div>
                <div className="text-slate-700">{a.approverName ?? 'Hệ thống'}</div>
                <div className="text-xs text-slate-500">{fmt(a.approvedAt)}</div>
                {a.comment && (
                  <div className="mt-1 rounded bg-slate-50 px-2 py-1 text-xs text-slate-600">
                    {a.comment}
                  </div>
                )}
              </div>
            </li>
          ))}
        </ol>
      </section>

      <section className="rounded-xl border border-slate-200 bg-white p-5 shadow-sm">
        <h2 className="mb-3 flex items-center gap-2 text-sm font-semibold text-slate-700">
          <History className="h-4 w-4" />
          Lịch sử điều chỉnh
        </h2>
        <ContractChangelogsTab contractId={c.id} />
      </section>
    </div>
  )
}

// 2-stage dept approval timeline (Migration 16). Group by phase × dept. Same
// pattern PE — block phase transition khi current phase có Review nhưng chưa
// Confirm → highlight amber để user biết "đang chờ TPB confirm".
function DeptApprovalsSection({
  rows,
  currentPhase,
}: {
  rows: ContractDepartmentApproval[]
  currentPhase: number
}) {
  const grouped = new Map<number, Map<string, ContractDepartmentApproval[]>>()
  for (const r of rows) {
    if (!grouped.has(r.phaseAtApproval)) grouped.set(r.phaseAtApproval, new Map())
    const byDept = grouped.get(r.phaseAtApproval)!
    if (!byDept.has(r.departmentId)) byDept.set(r.departmentId, [])
    byDept.get(r.departmentId)!.push(r)
  }
  const phaseOrder = [...grouped.keys()].sort((a, b) => a - b)

  return (
    <section className="rounded-xl border border-slate-200 bg-white p-5 shadow-sm">
      <h2 className="mb-1 flex items-center gap-2 text-sm font-semibold text-slate-700">
        <Users2 className="h-4 w-4" />
        Tiến trình duyệt 2-cấp phòng ban
      </h2>
      <p className="mb-3 text-xs text-slate-500">NV Review → TPB Confirm. Phase chỉ chuyển khi có Confirm.</p>
      <div className="space-y-3">
        {phaseOrder.map(phase => {
          const byDept = grouped.get(phase)!
          return (
            <div key={phase}>
              <div className={cn(
                'inline-block rounded px-1.5 py-0.5 text-[10px] font-medium',
                ContractPhaseColor[phase] ?? 'bg-slate-100 text-slate-700',
              )}>
                {ContractPhaseLabel[phase] ?? `Phase ${phase}`}
              </div>
              <div className="mt-1 space-y-1.5">
                {[...byDept.entries()].map(([deptId, stages]) => {
                  const review = stages.find(s => s.stage === ApprovalStage.Review)
                  const confirm = stages.find(s => s.stage === ApprovalStage.Confirm)
                  const deptName = stages[0]?.departmentName ?? '(không rõ phòng)'
                  const isPending = phase === currentPhase && review && !confirm
                  return (
                    <div key={deptId} className={cn(
                      'rounded border px-2 py-1.5 text-[11px]',
                      isPending ? 'border-amber-300 bg-amber-50' : 'border-slate-200 bg-slate-50',
                    )}>
                      <div className="font-medium text-slate-700">{deptName}</div>
                      <div className="mt-1 grid grid-cols-[60px_1fr] gap-x-2 gap-y-0.5">
                        <span className="text-slate-500">Review:</span>
                        <span className={review ? 'text-slate-700' : 'text-slate-400'}>
                          {review
                            ? <>✓ {review.approverName} <span className="text-slate-500">— {fmtTime(review.approvedAt)}</span>{review.comment && <span className="text-slate-500"> · "{review.comment}"</span>}</>
                            : '— chưa có'}
                        </span>
                        <span className="text-slate-500">Confirm:</span>
                        <span className={confirm ? 'text-emerald-700' : 'text-amber-700'}>
                          {confirm
                            ? <>✓ {confirm.approverName}{confirm.isBypassed && <span className="ml-1 rounded bg-fuchsia-100 px-1 text-[9px] text-fuchsia-700">bypass</span>} <span className="text-slate-500">— {fmtTime(confirm.approvedAt)}</span>{confirm.comment && <span className="text-slate-500"> · "{confirm.comment}"</span>}</>
                            : '⏳ chờ TPB confirm'}
                        </span>
                      </div>
                    </div>
                  )
                })}
              </div>
            </div>
          )
        })}
      </div>
    </section>
  )
}