// The seeker's own sigil — /profile. Edits display name, bio, gender, the
// procedural GhostGlyph avatar (form + hue), whether the profile is public,
// and an optional recovery email. Reads GET /api/profile/me, writes
// PATCH /api/profile (awaited, then a saved state — never optimistic).
//
// There is no image upload anywhere: the avatar is the same procedural glyph
// the entities wear, so there is nothing to moderate and no EXIF to leak.

import { useEffect, useMemo, useState } from 'react'
import { Link, Navigate } from 'react-router-dom'
import { useTranslation } from 'react-i18next'
import { GhostGlyph } from '../components/GhostGlyph'
import { useAuth } from '../state/auth'
import { genderLabel, progressPercent, rankTitle } from '../lib/hunterLabels'
import * as api from '../api'
import { AVATAR_FORMS, BIO_MAX, GENDERS, HUE_MAX } from '../api'
import type { Gender, OwnProfile } from '../api'
import type { GhostForm } from '../lib/types'
import './ProfilePage.css'

type LoadState = 'loading' | 'error' | 'ready'
type SaveState = 'idle' | 'saving' | 'saved' | 'error'

const NAME_MAX = 40
/** Same shape the backend accepts — deliberately loose, it only has to be
 * plausible enough to receive one recovery message. */
const EMAIL_RE = /^[^@\s]+@[^@\s.]+\.[^@\s]+$/

type Draft = {
  displayName: string
  bio: string
  gender: Gender
  form: GhostForm
  hue: number
  isPublic: boolean
  email: string
}

function draftFrom(profile: OwnProfile): Draft {
  return {
    displayName: profile.display_name ?? '',
    bio: profile.bio ?? '',
    gender: profile.gender ?? 'unspecified',
    form: profile.avatar_form ?? 'wisp',
    hue: profile.avatar_hue ?? 150,
    isPublic: profile.profile_public !== false,
    email: profile.email ?? '',
  }
}

export function ProfilePage() {
  const { t } = useTranslation()
  const { user, checking } = useAuth()
  const [profile, setProfile] = useState<OwnProfile | null>(null)
  const [state, setState] = useState<LoadState>('loading')
  const [draft, setDraft] = useState<Draft | null>(null)
  const [saveState, setSaveState] = useState<SaveState>('idle')
  const [saveError, setSaveError] = useState<string | null>(null)

  const isWanderer = (user?.username ?? '').startsWith('wanderer-')

  useEffect(() => {
    if (!user) return
    const controller = new AbortController()
    api
      .fetchOwnProfile(controller.signal)
      .then((data) => {
        setProfile(data)
        setDraft(draftFrom(data))
        setState('ready')
      })
      .catch(() => {
        if (!controller.signal.aborted) setState('error')
      })
    return () => controller.abort()
  }, [user])

  const bioRemaining = draft ? BIO_MAX - draft.bio.length : BIO_MAX
  const nameTooLong = (draft?.displayName.length ?? 0) > NAME_MAX
  const bioTooLong = bioRemaining < 0
  const emailInvalid = !!draft?.email.trim() && !EMAIL_RE.test(draft.email.trim())
  const invalid = nameTooLong || bioTooLong || emailInvalid

  const patch = useMemo<api.ProfileUpdate | null>(() => {
    if (!draft) return null
    return {
      display_name: draft.displayName.trim() || null,
      bio: draft.bio.trim() || null,
      gender: draft.gender,
      avatar_form: draft.form,
      avatar_hue: draft.hue,
      profile_public: draft.isPublic,
      email: draft.email.trim() || null,
    }
  }, [draft])

  function edit(patchDraft: Partial<Draft>) {
    setDraft((prev) => (prev ? { ...prev, ...patchDraft } : prev))
    setSaveState('idle')
    setSaveError(null)
  }

  async function handleSave(event: React.FormEvent) {
    event.preventDefault()
    if (!patch || invalid) return
    setSaveState('saving')
    setSaveError(null)
    try {
      // Awaited on purpose: the saved state must mean the veil actually
      // took the change, not that we hoped it would.
      const saved = await api.saveProfile(patch)
      setProfile(saved)
      setDraft(draftFrom(saved))
      setSaveState('saved')
    } catch (err) {
      setSaveState('error')
      setSaveError(err instanceof Error ? err.message : null)
    }
  }

  if (checking) return null
  if (!user) return <Navigate to="/enter" replace />

  return (
    <div className="profile-page">
      <header className="profile-header">
        <Link to="/seance" className="profile-back">
          {t('profile.back')}
        </Link>
        <h1 className="profile-title">{t('profile.title')}</h1>
        <p className="profile-subtitle">{t('profile.subtitle')}</p>
      </header>

      {isWanderer && (
        <div className="profile-wanderer" role="note">
          <p className="profile-wanderer-line">{t('profile.wanderer.body')}</p>
          <Link to="/enter" className="profile-wanderer-claim">
            {t('profile.wanderer.claim')}
          </Link>
        </div>
      )}

      {state === 'loading' && (
        <p className="profile-state" role="status">
          {t('profile.loading')}
        </p>
      )}
      {state === 'error' && (
        <p className="profile-state profile-state-error" role="alert">
          {t('profile.loadError')}
        </p>
      )}

      {state === 'ready' && draft && profile && (
        <form className="profile-form" onSubmit={handleSave} noValidate>
          <section className="profile-panel profile-sigil">
            <h2 className="profile-panel-title">{t('profile.avatar.heading')}</h2>
            <p className="profile-note">{t('profile.avatar.note')}</p>
            <div className="profile-preview">
              <GhostGlyph hue={draft.hue} form={draft.form} size={120} />
              <p className="profile-preview-name">
                {draft.displayName.trim() || profile.username}
              </p>
              <p className="profile-preview-rank">
                {t('profile.rankLine', {
                  title: rankTitle(t, profile.rank.title),
                  level: profile.rank.level,
                })}
              </p>
            </div>

            <div
              className="profile-chips"
              role="group"
              aria-label={t('profile.avatar.formLabel')}
            >
              {AVATAR_FORMS.map((form) => (
                <button
                  key={form}
                  type="button"
                  className={`profile-chip${draft.form === form ? ' profile-chip-active' : ''}`}
                  aria-pressed={draft.form === form}
                  onClick={() => edit({ form })}
                >
                  {t(`codex.form.${form}`, form)}
                </button>
              ))}
            </div>

            <label className="profile-field profile-hue">
              <span className="profile-label">
                {t('profile.avatar.hueLabel', { hue: draft.hue })}
              </span>
              <input
                type="range"
                min={0}
                max={HUE_MAX}
                value={draft.hue}
                className="profile-hue-slider"
                onChange={(e) => edit({ hue: Number(e.target.value) })}
              />
            </label>
          </section>

          <section className="profile-panel">
            <h2 className="profile-panel-title">{t('profile.identity.heading')}</h2>

            <label className="profile-field">
              <span className="profile-label">{t('profile.identity.nameLabel')}</span>
              <input
                type="text"
                className="profile-input"
                value={draft.displayName}
                maxLength={NAME_MAX * 2}
                placeholder={profile.username}
                onChange={(e) => edit({ displayName: e.target.value })}
              />
              <span className="profile-hint">{t('profile.identity.nameHint')}</span>
              {nameTooLong && (
                <span className="profile-error" role="alert">
                  {t('profile.identity.nameTooLong', { max: NAME_MAX })}
                </span>
              )}
            </label>

            <label className="profile-field">
              <span className="profile-label">{t('profile.identity.bioLabel')}</span>
              <textarea
                className="profile-textarea"
                rows={4}
                value={draft.bio}
                onChange={(e) => edit({ bio: e.target.value })}
              />
              <span
                className={`profile-count${bioTooLong ? ' profile-count-over' : ''}`}
                aria-live="polite"
              >
                {t('profile.identity.bioCount', { remaining: bioRemaining, max: BIO_MAX })}
              </span>
              {bioTooLong && (
                <span className="profile-error" role="alert">
                  {t('profile.identity.bioTooLong', { max: BIO_MAX })}
                </span>
              )}
            </label>

            <div
              className="profile-chips"
              role="group"
              aria-label={t('profile.gender.label')}
            >
              {GENDERS.map((gender) => (
                <button
                  key={gender}
                  type="button"
                  className={`profile-chip${draft.gender === gender ? ' profile-chip-active' : ''}`}
                  aria-pressed={draft.gender === gender}
                  onClick={() => edit({ gender })}
                >
                  {genderLabel(t, gender)}
                </button>
              ))}
            </div>
          </section>

          <section className="profile-panel">
            <h2 className="profile-panel-title">{t('profile.veil.heading')}</h2>

            <label className="profile-toggle">
              <input
                type="checkbox"
                checked={draft.isPublic}
                onChange={(e) => edit({ isPublic: e.target.checked })}
              />
              <span className="profile-toggle-text">
                {draft.isPublic ? t('profile.veil.public') : t('profile.veil.private')}
              </span>
            </label>
            <p className="profile-note">
              {draft.isPublic ? t('profile.veil.publicNote') : t('profile.veil.privateNote')}
            </p>

            <label className="profile-field">
              <span className="profile-label">{t('profile.email.label')}</span>
              <input
                type="email"
                className="profile-input"
                value={draft.email}
                autoComplete="email"
                onChange={(e) => edit({ email: e.target.value })}
              />
              <span className="profile-hint">{t('profile.email.note')}</span>
              {emailInvalid && (
                <span className="profile-error" role="alert">
                  {t('profile.email.invalid')}
                </span>
              )}
            </label>
          </section>

          <div className="profile-actions">
            <button
              type="submit"
              className="profile-save"
              disabled={saveState === 'saving' || invalid}
            >
              {saveState === 'saving' ? t('profile.saving') : t('profile.save')}
            </button>
            {profile.profile_public && (
              <Link to={`/hunters/${profile.username}`} className="profile-view-link">
                {t('profile.viewPublic')}
              </Link>
            )}
            {saveState === 'saved' && (
              <p className="profile-saved" role="status">
                {t('profile.saved')}
              </p>
            )}
            {saveState === 'error' && (
              <p className="profile-error" role="alert">
                {saveError ?? t('profile.saveError')}
              </p>
            )}
          </div>
        </form>
      )}
    </div>
  )
}