'use client';

import { useState } from 'react';
import { useRouter } from 'next/navigation';
import { Check, Loader2, Upload } from 'lucide-react';
import type { RouterOutputs } from '@/lib/trpc';
import { api } from '@/lib/trpc';
import {
  DEFAULT_SERVICE_RADIUS_M,
  MAX_SERVICE_RADIUS_M,
  MIN_SERVICE_RADIUS_M,
} from '@linkder/shared';
import { cn } from '@/lib/utils';
import { uploadFile } from '@/lib/upload';
import {
  Button,
  Chip,
  Field,
  FieldNote,
  FieldSet,
  FormError,
  Input,
  Section,
  StickyAction,
  Textarea,
} from '@/components/ui';

type Categories = RouterOutputs['job']['categories'];
type Profile = RouterOutputs['pro']['me'];

const CITY = {
  lat: Number(process.env.NEXT_PUBLIC_CITY_LAT ?? 41.3874),
  lng: Number(process.env.NEXT_PUBLIC_CITY_LNG ?? 2.1686),
};

const STEPS = ['Trade', 'About you', 'Photos', 'Documents'] as const;

export function OnboardingWizard({
  categories,
  initialProfile,
  hasContactableEmail,
}: {
  categories: Categories;
  initialProfile: Profile;
  hasContactableEmail: boolean;
}) {
  const router = useRouter();
  const [step, setStep] = useState(0);
  const [error, setError] = useState<string | null>(null);

  const [categoryIds, setCategoryIds] = useState<string[]>(initialProfile?.categoryIds ?? []);
  const [headline, setHeadline] = useState(initialProfile?.headline ?? '');
  const [bio, setBio] = useState(initialProfile?.bio ?? '');
  const [hourlyRate, setHourlyRate] = useState(
    initialProfile ? String(initialProfile.hourlyRateCents / 100) : '',
  );
  const [yearsExperience, setYearsExperience] = useState(
    String(initialProfile?.yearsExperience ?? ''),
  );
  const [radiusKm, setRadiusKm] = useState(
    (initialProfile?.serviceRadiusM ?? DEFAULT_SERVICE_RADIUS_M) / 1000,
  );
  const [location, setLocation] = useState(initialProfile?.baseLocation ?? CITY);
  const [email, setEmail] = useState('');

  const utils = api.useUtils();
  const upsert = api.pro.upsertProfile.useMutation();
  const addMedia = api.pro.addMedia.useMutation();
  const addCredential = api.pro.addCredential.useMutation();
  const setEmailMutation = api.user.setEmail.useMutation();
  const submit = api.pro.submitForReview.useMutation({
    onSuccess: () => router.push('/pro'),
    onError: (e) => setError(e.message),
  });

  const media = initialProfile?.media ?? [];
  const credentials = initialProfile?.credentials ?? [];

  async function saveProfile() {
    setError(null);
    const rateCents = Math.round(Number(hourlyRate) * 100);
    if (!Number.isFinite(rateCents) || rateCents <= 0) {
      setError('Enter your hourly rate.');
      return false;
    }
    try {
      await upsert.mutateAsync({
        headline,
        bio,
        hourlyRateCents: rateCents,
        yearsExperience: Number(yearsExperience) || 0,
        categoryIds,
        location,
        serviceRadiusM: Math.round(radiusKm * 1000),
      });
      await utils.pro.me.invalidate();
      return true;
    } catch (e) {
      setError((e as Error).message);
      return false;
    }
  }

  return (
    <div>
      <ol className="mb-10 flex gap-2" aria-label="Progress">
        {STEPS.map((label, i) => (
          <li key={label} className="flex-1">
            <div
              className={cn(
                'h-1 rounded-pill transition-colors duration-[200ms] ease-standard',
                i <= step ? 'bg-brand-500' : 'bg-inset',
              )}
            />
            <span
              className={cn(
                'mt-2 block text-meta',
                i === step ? 'font-semibold text-strong' : 'text-muted',
              )}
              aria-current={i === step ? 'step' : undefined}
            >
              {label}
            </span>
          </li>
        ))}
      </ol>

      {step === 0 && (
        <Section
          title="What do you do?"
          hint="Pick every trade you actually take jobs for — you will only be shown matching work."
        >
          <div className="flex flex-wrap gap-2">
            {categories.map((c) => {
              const selected = categoryIds.includes(c.id);
              return (
                <Chip
                  key={c.id}
                  selected={selected}
                  onClick={() =>
                    setCategoryIds((prev) =>
                      selected ? prev.filter((id) => id !== c.id) : [...prev, c.id].slice(0, 5),
                    )
                  }
                >
                  {c.name}
                </Chip>
              );
            })}
          </div>
          <Nav
            onNext={() => {
              if (categoryIds.length === 0) return setError('Pick at least one trade.');
              setError(null);
              setStep(1);
            }}
          />
        </Section>
      )}

      {step === 1 && (
        <Section title="About you" hint="This is what a customer reads on your card.">
          <Field label="Headline" hint="e.g. Emergency plumber, 15 years in Barcelona">
            <Input
              value={headline}
              onChange={(e) => setHeadline(e.target.value)}
              maxLength={100}
            />
          </Field>

          <Field label="About your work">
            <Textarea
              value={bio}
              onChange={(e) => setBio(e.target.value)}
              rows={5}
              maxLength={2000}
            />
            <FieldNote>{bio.length}/2000, minimum 30</FieldNote>
          </Field>

          <div className="grid grid-cols-2 gap-3">
            <Field label="Hourly rate (€)">
              <Input
                value={hourlyRate}
                onChange={(e) => setHourlyRate(e.target.value.replace(/[^0-9.]/g, ''))}
                inputMode="decimal"
              />
            </Field>
            <Field label="Years experience">
              <Input
                value={yearsExperience}
                onChange={(e) => setYearsExperience(e.target.value.replace(/\D/g, ''))}
                inputMode="numeric"
              />
            </Field>
          </div>

          <Field
            label={`How far will you travel? ${radiusKm} km`}
            hint="You will only be shown jobs inside this radius."
          >
            <input
              type="range"
              min={MIN_SERVICE_RADIUS_M / 1000}
              max={MAX_SERVICE_RADIUS_M / 1000}
              value={radiusKm}
              onChange={(e) => setRadiusKm(Number(e.target.value))}
              className="w-full accent-brand-500"
            />
          </Field>

          <Button
            type="button"
            variant="ghost"
            size="sm"
            className="self-start"
            onClick={() =>
              navigator.geolocation?.getCurrentPosition(
                (pos) => setLocation({ lat: pos.coords.latitude, lng: pos.coords.longitude }),
                () => setError('We could not get your location. The city centre will be used.'),
              )
            }
          >
            Use my current location as my base
          </Button>

          <Nav
            onBack={() => setStep(0)}
            busy={upsert.isPending}
            onNext={async () => {
              if (await saveProfile()) setStep(2);
            }}
          />
        </Section>
      )}

      {step === 2 && (
        <Section
          title="Photos"
          hint="A face and a few examples of your work. This is the single biggest thing customers judge you on."
        >
          <UploadList
            kind="pro_photo"
            existing={media.map((m) => m.url)}
            onUploaded={async (url) => {
              await addMedia.mutateAsync({ url });
              await utils.pro.me.invalidate();
              router.refresh();
            }}
            onError={setError}
          />
          <Nav onBack={() => setStep(1)} onNext={() => setStep(3)} />
        </Section>
      )}

      {step === 3 && (
        <Section
          title="Documents"
          hint="We check these by hand before your profile goes live. They are never shown to customers."
        >
          {!hasContactableEmail && (
            <div className="flex flex-col gap-2">
              <Field
                label="Email address"
                hint="Required for pros — payout statements, tax records and dispute notices go here."
              >
                <Input type="email" value={email} onChange={(e) => setEmail(e.target.value)} />
              </Field>
              <Button
                type="button"
                variant="ghost"
                size="sm"
                className="self-start"
                onClick={async () => {
                  try {
                    await setEmailMutation.mutateAsync({ email });
                    setError(null);
                    router.refresh();
                  } catch (e) {
                    setError((e as Error).message);
                  }
                }}
              >
                Save email
              </Button>
            </div>
          )}

          {(['id', 'insurance', 'licence'] as const).map((kind) => (
            <FieldSet
              key={kind}
              label={
                kind === 'id'
                  ? 'Photo ID (required)'
                  : kind === 'insurance'
                    ? 'Public liability insurance (required)'
                    : 'Trade licence (if your trade needs one)'
              }
            >
              <UploadList
                kind="credential"
                existing={credentials.filter((c) => c.kind === kind).map((c) => c.fileKey)}
                onUploaded={async (url) => {
                  await addCredential.mutateAsync({ kind, fileKey: url });
                  await utils.pro.me.invalidate();
                  router.refresh();
                }}
                onError={setError}
              />
            </FieldSet>
          ))}

          <StickyAction>
            <div className="flex gap-3">
              <Button type="button" variant="outline" size="lg" onClick={() => setStep(2)}>
                Back
              </Button>
              <Button
                type="button"
                size="lg"
                className="flex-1"
                busy={submit.isPending}
                onClick={() => submit.mutate()}
              >
                Submit for review
              </Button>
            </div>
          </StickyAction>
        </Section>
      )}

      {error && (
        <div className="mt-6">
          <FormError>{error}</FormError>
        </div>
      )}
    </div>
  );
}

function Nav({
  onBack,
  onNext,
  busy,
}: {
  onBack?: () => void;
  onNext: () => void | Promise<void>;
  busy?: boolean;
}) {
  return (
    <StickyAction>
      <div className="flex gap-3">
        {onBack && (
          <Button type="button" variant="outline" size="lg" onClick={onBack}>
            Back
          </Button>
        )}
        <Button type="button" size="lg" className="flex-1" busy={busy} onClick={() => void onNext()}>
          Continue
        </Button>
      </div>
    </StickyAction>
  );
}

function UploadList({
  kind,
  existing,
  onUploaded,
  onError,
}: {
  kind: 'pro_photo' | 'credential';
  existing: string[];
  onUploaded: (url: string) => Promise<void>;
  onError: (message: string) => void;
}) {
  const [busy, setBusy] = useState(false);
  const presign = api.upload.presign.useMutation();

  return (
    <div className="flex flex-col gap-3">
      {existing.length > 0 && (
        <ul className="flex flex-wrap gap-2">
          {existing.map((url) => (
            <li
              key={url}
              className="flex items-center gap-1.5 rounded-pill border border-go-100 bg-go-50 px-3 py-1.5 text-meta text-go-700"
            >
              <Check className="h-4 w-4" aria-hidden />
              Uploaded
            </li>
          ))}
        </ul>
      )}
      <label
        className={cn(
          'flex cursor-pointer items-center justify-center gap-2 rounded-card border border-dashed',
          'border-hairline px-4 py-8 text-body-sm text-muted',
          'transition-colors duration-[120ms] ease-standard hover:border-brand-500 hover:text-strong',
        )}
      >
        {busy ? (
          <Loader2 className="h-4 w-4 animate-spin" aria-hidden />
        ) : (
          <Upload className="h-4 w-4" aria-hidden />
        )}
        {busy ? 'Uploading…' : 'Choose a file'}
        <input
          type="file"
          className="sr-only"
          accept={kind === 'credential' ? 'image/*,application/pdf' : 'image/*'}
          onChange={async (event) => {
            const file = event.target.files?.[0];
            if (!file) return;
            setBusy(true);
            try {
              const url = await uploadFile(file, kind, (input) => presign.mutateAsync(input));
              await onUploaded(url);
            } catch (e) {
              onError((e as Error).message);
            } finally {
              setBusy(false);
              event.target.value = '';
            }
          }}
        />
      </label>
    </div>
  );
}