"use client";

import { useRouter } from "next/navigation";
import { useState } from "react";
import { changeEmployeeData } from "@/actions/employees";
import { AngehoerigeSection } from "@/components/employees/AngehoerigeSection";
import { RoleEmploymentFields, type RoleEmploymentValue } from "@/components/employees/RoleEmploymentFields";
import { SvNummerField } from "@/components/employees/SvNummerField";
import { TitleFields, type TitleValue } from "@/components/employees/TitleFields";
import { Button } from "@/components/ui/Button";
import { CountryPicker } from "@/components/ui/CountryPicker";
import { Field, SelectField, TextField } from "@/components/ui/Field";
import { SlideOver } from "@/components/ui/SlideOver";
import { useToast } from "@/components/ui/Toast";
import { UN_COUNTRIES } from "@/lib/countries";
import { fmtFullName, todayIso } from "@/lib/format";
import { isValidSvnr, requiresAustrianSvnr } from "@/lib/svnr";
import type { ContractType, Database, EmploymentType, GenderType } from "@/lib/supabase/types";

type EmployeeRow = Database["public"]["Tables"]["employees"]["Row"];
type Dependent = Database["public"]["Tables"]["employee_dependents"]["Row"];

export function DatenAendernPanel({
  open,
  onClose,
  employee,
  dependents,
  locationCountry,
}: {
  open: boolean;
  onClose: () => void;
  employee: EmployeeRow;
  dependents: Dependent[];
  locationCountry: string | null | undefined;
}) {
  const { showToast } = useToast();
  const router = useRouter();
  const [pending, setPending] = useState(false);
  // The DB trigger would reject a bad number anyway; catching it here keeps
  // the whole effective-dated change from being thrown away on submit.
  const [effectiveDate, setEffectiveDate] = useState(todayIso);

  const [firstName, setFirstName] = useState(employee.first_name);
  const [lastName, setLastName] = useState(employee.last_name);
  const [titles, setTitles] = useState<TitleValue>({ titlePrefix: employee.title_prefix ?? [], titleSuffix: employee.title_suffix ?? [] });
  function updateTitles(patch: Partial<TitleValue>) {
    setTitles((prev) => ({ ...prev, ...patch }));
  }
  const [gender, setGender] = useState<GenderType>(employee.gender);
  const [birthDate, setBirthDate] = useState(employee.birth_date);
  const [svNummer, setSvNummer] = useState(employee.sv_nummer ?? "");
  const svNummerOk =
    !svNummer.trim() || !requiresAustrianSvnr(locationCountry) || isValidSvnr(svNummer, birthDate || null);
  const [nationality, setNationality] = useState(employee.nationality);
  const [address, setAddress] = useState(employee.address ?? "");
  const [postalCode, setPostalCode] = useState(employee.postal_code ?? "");
  const [city, setCity] = useState(employee.city ?? "");
  const [addressCountry, setAddressCountry] = useState(employee.address_country ?? "Österreich");
  const [email, setEmail] = useState(employee.email);
  const [phone, setPhone] = useState(employee.phone ?? "");

  const [employmentType, setEmploymentType] = useState<EmploymentType>(employee.employment_type);
  const [weeklyHours, setWeeklyHours] = useState(String(employee.weekly_hours));
  const [contractType, setContractType] = useState<ContractType>(employee.contract_type);
  const [contractEndDate, setContractEndDate] = useState(employee.contract_end_date ?? "");

  const [role, setRole] = useState<RoleEmploymentValue>({
    workerType: employee.worker_type ?? "Angestellte:r",
    collectiveAgreement: employee.collective_agreement ?? "Handel",
    workDays: employee.work_days ?? ["Mo", "Di", "Mi", "Do", "Fr"],
    isBetriebsrat: employee.is_betriebsrat ?? false,
    hasDienstwagen: employee.has_dienstwagen ?? false,
    isLateraleFuehrung: employee.is_laterale_fuehrung ?? false,
    isCLevel: employee.is_c_level ?? false,
  });
  function updateRole(patch: Partial<RoleEmploymentValue>) {
    setRole((prev) => ({ ...prev, ...patch }));
  }

  function handleEmploymentTypeChange(value: EmploymentType) {
    setEmploymentType(value);
    if (value === "Vollzeit") setWeeklyHours("38.5");
  }

  async function handleSubmit() {
    if (employmentType === "Teilzeit" && (Number(weeklyHours) <= 0 || Number(weeklyHours) >= 38.5)) {
      showToast("Wochenstunden bei Teilzeit müssen zwischen 0 und 38,5 liegen.", "error");
      return;
    }
    if (contractType === "befristet" && !contractEndDate) {
      showToast("Bei befristetem Vertrag ist ein Enddatum erforderlich.", "error");
      return;
    }
    if (role.workDays.length === 0) {
      showToast("Mindestens ein Arbeitstag muss ausgewählt sein.", "error");
      return;
    }
    if (!effectiveDate) {
      showToast("Bitte ein Wirksam-ab-Datum angeben.", "error");
      return;
    }
    setPending(true);
    const result = await changeEmployeeData({
      employee_id: employee.id,
      effective_date: effectiveDate,
      person: {
        first_name: firstName,
        last_name: lastName,
        title_prefix: titles.titlePrefix,
        title_suffix: titles.titleSuffix,
        gender,
        birth_date: birthDate,
        sv_nummer: svNummer,
        nationality,
        address,
        postal_code: postalCode,
        city,
        address_country: addressCountry,
        email,
        phone,
      },
      contract: {
        employment_type: employmentType,
        weekly_hours: Number(weeklyHours),
        contract_type: contractType,
        contract_end_date: contractType === "befristet" ? contractEndDate : "",
      },
      role: {
        worker_type: role.workerType,
        collective_agreement: role.collectiveAgreement,
        work_days: role.workDays,
        is_betriebsrat: role.isBetriebsrat,
        has_dienstwagen: role.hasDienstwagen,
        is_laterale_fuehrung: role.isLateraleFuehrung,
        is_c_level: role.isCLevel,
      },
    });
    setPending(false);
    if (result.success) {
      showToast("Daten aktualisiert.");
      router.refresh();
      onClose();
    } else {
      showToast(result.error ?? "Fehler beim Speichern.", "error");
    }
  }

  return (
    <SlideOver
      open={open}
      onClose={onClose}
      title="Daten ändern"
      subtitle={`${fmtFullName(employee.first_name, employee.last_name, employee.title_prefix, employee.title_suffix)} · ${employee.job_title}`}
      footer={
        <>
          <Button variant="ghost" onClick={onClose}>
            Abbrechen
          </Button>
          <Button
            onClick={handleSubmit}
            pending={pending}
            disabled={!svNummerOk}
            title={svNummerOk ? undefined : "Die SV-Nummer ist ungültig."}
          >
            Speichern
          </Button>
        </>
      }
    >
      <div className="flex flex-col gap-6">
        <TextField label="Wirksam ab" required type="date" value={effectiveDate} onChange={setEffectiveDate} />

        <div>
          <h3 className="mb-3 text-sm font-bold text-ink">Person</h3>
          <div className="flex flex-col gap-3">
            <div className="grid grid-cols-1 gap-3 sm:grid-cols-2">
              <TextField label="Vorname" dense value={firstName} onChange={setFirstName} />
              <TextField label="Nachname" dense value={lastName} onChange={setLastName} />
            </div>
            <TitleFields value={titles} onChange={updateTitles} />
            <div className="grid grid-cols-1 gap-3 sm:grid-cols-2">
              <SelectField
                label="Geschlecht"
                dense
                value={gender}
                onChange={(v) => setGender(v as GenderType)}
                options={[
                  { value: "m", label: "männlich" },
                  { value: "w", label: "weiblich" },
                ]}
              />
              <TextField label="Geburtsdatum" dense type="date" value={birthDate} onChange={setBirthDate} />
            </div>
            <SvNummerField value={svNummer} onChange={setSvNummer} locationCountry={locationCountry} birthDate={birthDate || null} dense />
            <Field label="Staatsbürgerschaft" dense>
              {(p) => (
                <CountryPicker {...p} value={nationality} onChange={setNationality} countries={UN_COUNTRIES} placeholder="Staatsbürgerschaft suchen…" />
              )}
            </Field>
            <TextField label="Adresse (Straße und Hausnummer)" dense value={address} onChange={setAddress} />
            <div className="grid grid-cols-[minmax(0,1fr)_minmax(0,2fr)] gap-3">
              <TextField label="Postleitzahl" dense inputMode="numeric" value={postalCode} onChange={setPostalCode} />
              <TextField label="Ort" dense value={city} onChange={setCity} />
            </div>
            <Field label="Land" dense>
              {(p) => <CountryPicker {...p} value={addressCountry} onChange={setAddressCountry} countries={UN_COUNTRIES} placeholder="Land suchen…" />}
            </Field>
            <TextField label="E-Mail" dense type="email" value={email} onChange={setEmail} />
            <TextField label="Telefon" dense type="tel" value={phone} onChange={setPhone} />
          </div>
        </div>

        <div>
          <h3 className="mb-3 text-sm font-bold text-ink">Vertrag</h3>
          <div className="flex flex-col gap-3">
            <SelectField
              label="Beschäftigungsausmaß"
              dense
              value={employmentType}
              onChange={(v) => handleEmploymentTypeChange(v as EmploymentType)}
              options={[
                { value: "Vollzeit", label: "Vollzeit" },
                { value: "Teilzeit", label: "Teilzeit" },
              ]}
            />
            <TextField
              label="Wochenstunden"
              dense
              type="number"
              step="0.5"
              value={weeklyHours}
              disabled={employmentType === "Vollzeit"}
              onChange={setWeeklyHours}
            />
            <SelectField
              label="Vertragsart"
              dense
              value={contractType}
              onChange={(v) => setContractType(v as ContractType)}
              options={[
                { value: "unbefristet", label: "unbefristet" },
                { value: "befristet", label: "befristet" },
              ]}
            />
            {contractType === "befristet" && (
              <TextField label="Befristet bis" required dense type="date" value={contractEndDate} onChange={setContractEndDate} />
            )}
          </div>
        </div>

        <div>
          <h3 className="mb-3 text-sm font-bold text-ink">Rolle & Anstellung</h3>
          <RoleEmploymentFields value={role} onChange={updateRole} />
        </div>

        <AngehoerigeSection employeeId={employee.id} dependents={dependents} effectiveDate={effectiveDate} />
      </div>
    </SlideOver>
  );
}
