import { useState } from "react";
import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import { CalendarDays, Plus, LogIn, LogOut } from "lucide-react";
import {
  getTimesheet, getAttendance, getLeave, getOvertime, punch, createLeave,
  createOvertime, cancelLeave,
} from "@/lib/api";
import {
  Card, Button, Badge, Stat, PageHeader, Modal, Field, Input, Select,
  Textarea, Tabs, Progress, EmptyState, LoadingState,
} from "@/components/ui";
import {
  formatDate, formatTime, minutesToHM, REQ_STATUS_META, LEAVE_LABELS, classNames,
} from "@/lib/format";
import type { LeaveType } from "@/types";

const THIS_MONTH = new Date().toISOString().slice(0, 7);

export function AttendancePage() {
  const qc = useQueryClient();
  const [tab, setTab] = useState("timesheet");
  const [leaveOpen, setLeaveOpen] = useState(false);
  const [otOpen, setOtOpen] = useState(false);

  const tsQ = useQuery({ queryKey: ["timesheet"], queryFn: () => getTimesheet({}) });
  const attQ = useQuery({ queryKey: ["attendance", THIS_MONTH], queryFn: () => getAttendance({ month: THIS_MONTH }) });
  const leaveQ = useQuery({ queryKey: ["leave-mine"], queryFn: () => getLeave() });
  const otQ = useQuery({ queryKey: ["ot-mine"], queryFn: () => getOvertime() });

  const punchM = useMutation({
    mutationFn: punch,
    onSuccess: () => { qc.invalidateQueries({ queryKey: ["attendance", THIS_MONTH] }); qc.invalidateQueries({ queryKey: ["timesheet"] }); },
  });

  const ts = tsQ.data;

  return (
    <div>
      <PageHeader
        title="근무"
        description="출퇴근 체크와 휴가·초과근무 신청을 관리합니다. 본인 기록만 표시됩니다."
        action={
          <div className="flex gap-2">
            <Button variant="secondary" icon={<LogIn size={16} />} onClick={() => punchM.mutate()}>출근</Button>
            <Button icon={<LogOut size={16} />} onClick={() => punchM.mutate()}>퇴근</Button>
          </div>
        }
      />

      {ts && (
        <div className="grid grid-cols-2 lg:grid-cols-4 gap-4 mb-4">
          <Stat label={`${ts.year}.${String(ts.month).padStart(2, "0")} 인정 근무`} value={minutesToHM(ts.recognizedTotal)} sub={`근무 ${minutesToHM(ts.workedMinutes)} + 인정휴가 ${minutesToHM(ts.leaveMinutes)}`} />
          <Stat label="월 소정근로" value={minutesToHM(ts.standardMinutes)} sub={`영업일 ${ts.businessDays}일`} />
          <Stat label="출근일" value={`${ts.daysPresent}일`} sub={`초과근무 ${minutesToHM(ts.overtimeMinutes)}`} />
          <Card className="p-5">
            <div className="text-xs font-medium text-ink-secondary">월 근로 달성률</div>
            <div className="mt-2 text-2xl font-bold font-num text-navy">{ts.fulfillmentPct.toFixed(0)}%</div>
            <div className="mt-2"><Progress pct={ts.fulfillmentPct} color={ts.fulfillmentPct >= 100 ? "#12B76A" : "#11224F"} /></div>
          </Card>
        </div>
      )}

      <Card>
        <div className="px-3 pt-2 flex items-center justify-between">
          <Tabs
            active={tab}
            onChange={setTab}
            tabs={[
              { key: "timesheet", label: "근무 기록" },
              { key: "leave", label: "휴가/공가", badge: leaveQ.data?.filter((l) => l.status === "pending").length },
              { key: "overtime", label: "초과근무", badge: otQ.data?.filter((o) => o.status === "pending").length },
            ]}
          />
          {tab === "leave" && <Button size="sm" icon={<Plus size={14} />} onClick={() => setLeaveOpen(true)}>휴가 신청</Button>}
          {tab === "overtime" && <Button size="sm" icon={<Plus size={14} />} onClick={() => setOtOpen(true)}>초과근무 신청</Button>}
        </div>

        <div className="p-4">
          {tab === "timesheet" && (
            attQ.isLoading ? <LoadingState /> : (attQ.data?.length ?? 0) === 0 ? <EmptyState title="이번 달 근무 기록이 없습니다" icon={<CalendarDays size={28} />} /> : (
              <div className="overflow-x-auto">
                <table className="dense-table">
                  <thead><tr><th>날짜</th><th>출근</th><th>퇴근</th><th>근무시간</th><th>비고</th></tr></thead>
                  <tbody>
                    {attQ.data!.map((a) => (
                      <tr key={a.id}>
                        <td className="tabular">{formatDate(a.date)}</td>
                        <td className="tabular">{formatTime(a.clockIn)}</td>
                        <td className="tabular">{formatTime(a.clockOut)}</td>
                        <td className="tabular">{minutesToHM(a.workMinutes)}</td>
                        <td className="text-ink-muted">{a.note || "—"}</td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>
            )
          )}

          {tab === "leave" && (
            leaveQ.isLoading ? <LoadingState /> : (leaveQ.data?.length ?? 0) === 0 ? <EmptyState title="신청 내역이 없습니다" /> : (
              <table className="dense-table">
                <thead><tr><th>종류</th><th>기간</th><th>일수</th><th>사유</th><th>상태</th><th></th></tr></thead>
                <tbody>
                  {leaveQ.data!.map((l) => {
                    const m = REQ_STATUS_META[l.status];
                    return (
                      <tr key={l.id}>
                        <td>{LEAVE_LABELS[l.type]}</td>
                        <td className="tabular">{formatDate(l.startDate)}{l.endDate && l.endDate !== l.startDate ? ` ~ ${formatDate(l.endDate)}` : ""}</td>
                        <td className="tabular">{l.days}일</td>
                        <td className="text-ink-secondary max-w-[240px] truncate">{l.reason}</td>
                        <td><Badge label={m.label} fg={m.fg} bg={m.bg} dot /></td>
                        <td className="text-right">{l.status === "pending" && <button className="text-xs text-[#B42318]" onClick={() => cancelLeave(l.id).then(() => qc.invalidateQueries({ queryKey: ["leave-mine"] }))}>취소</button>}</td>
                      </tr>
                    );
                  })}
                </tbody>
              </table>
            )
          )}

          {tab === "overtime" && (
            otQ.isLoading ? <LoadingState /> : (otQ.data?.length ?? 0) === 0 ? <EmptyState title="신청 내역이 없습니다" /> : (
              <table className="dense-table">
                <thead><tr><th>날짜</th><th>시간</th><th>사유</th><th>상태</th></tr></thead>
                <tbody>
                  {otQ.data!.map((o) => {
                    const m = REQ_STATUS_META[o.status];
                    return (
                      <tr key={o.id}>
                        <td className="tabular">{formatDate(o.date)}</td>
                        <td className="tabular">{minutesToHM(o.minutes)}</td>
                        <td className="text-ink-secondary">{o.reason}</td>
                        <td><Badge label={m.label} fg={m.fg} bg={m.bg} dot /></td>
                      </tr>
                    );
                  })}
                </tbody>
              </table>
            )
          )}
        </div>
      </Card>

      <LeaveModal open={leaveOpen} onClose={() => setLeaveOpen(false)} onDone={() => qc.invalidateQueries({ queryKey: ["leave-mine"] })} />
      <OvertimeModal open={otOpen} onClose={() => setOtOpen(false)} onDone={() => qc.invalidateQueries({ queryKey: ["ot-mine"] })} />
    </div>
  );
}

function LeaveModal({ open, onClose, onDone }: { open: boolean; onClose: () => void; onDone: () => void }) {
  const [type, setType] = useState<LeaveType>("annual");
  const [startDate, setStart] = useState("");
  const [endDate, setEnd] = useState("");
  const [reason, setReason] = useState("");
  const m = useMutation({
    mutationFn: () => createLeave({ type, startDate, endDate: endDate || startDate, reason }),
    onSuccess: () => { onDone(); onClose(); setReason(""); },
  });
  return (
    <Modal
      open={open} onClose={onClose} title="휴가 / 공가 신청"
      footer={<><Button variant="secondary" onClick={onClose}>취소</Button><Button disabled={!startDate || m.isPending} onClick={() => m.mutate()}>신청</Button></>}
    >
      <div className="space-y-4">
        <Field label="종류"><Select value={type} onChange={(e) => setType(e.target.value as LeaveType)}>
          {Object.entries(LEAVE_LABELS).map(([k, v]) => <option key={k} value={k}>{v}</option>)}
        </Select></Field>
        <div className="grid grid-cols-2 gap-3">
          <Field label="시작일"><Input type="date" value={startDate} onChange={(e) => setStart(e.target.value)} /></Field>
          <Field label="종료일"><Input type="date" value={endDate} onChange={(e) => setEnd(e.target.value)} /></Field>
        </div>
        <Field label="사유"><Textarea value={reason} onChange={(e) => setReason(e.target.value)} placeholder="사유를 입력하세요" /></Field>
        <p className="text-xs text-ink-muted">※ 신청 후 관리자 승인이 필요합니다.</p>
      </div>
    </Modal>
  );
}

function OvertimeModal({ open, onClose, onDone }: { open: boolean; onClose: () => void; onDone: () => void }) {
  const [date, setDate] = useState("");
  const [hours, setHours] = useState("2");
  const [reason, setReason] = useState("");
  const m = useMutation({
    mutationFn: () => createOvertime({ date, minutes: Math.round(parseFloat(hours) * 60), reason }),
    onSuccess: () => { onDone(); onClose(); setReason(""); },
  });
  return (
    <Modal
      open={open} onClose={onClose} title="초과근무 신청"
      footer={<><Button variant="secondary" onClick={onClose}>취소</Button><Button disabled={!date || m.isPending} onClick={() => m.mutate()}>신청</Button></>}
    >
      <div className="space-y-4">
        <Field label="날짜"><Input type="date" value={date} onChange={(e) => setDate(e.target.value)} /></Field>
        <Field label="시간(시간 단위)"><Input type="number" step="0.5" value={hours} onChange={(e) => setHours(e.target.value)} /></Field>
        <Field label="사유"><Textarea value={reason} onChange={(e) => setReason(e.target.value)} /></Field>
        <p className={classNames("text-xs text-ink-muted")}>※ 초과근무는 관리자만 확인·승인합니다.</p>
      </div>
    </Modal>
  );
}