'use client'

import { useState, useTransition } from 'react'
import { roleAdminText } from '@/lib/i18n/admin'
import { OPT_IN_PERMISSIONS, PERMISSIONS, type Permission } from '@/lib/auth/permissions'
import { saveRoleMapping } from './actions'

export type RoleRowData = {
  discordRoleId: string
  label: string
  clearanceLevel: number
  grantsMembership: boolean
  category: string
  permissions: string[]
  isPresent: boolean
}

const CATEGORIES = ['MEMBERSHIP', 'RANK', 'CLEARANCE', 'UNSORTED'] as const

/**
 * Eine Rolle. Bewusst nicht optimistisch: eine Änderung am Rollen-Mapping ist
 * folgenreich und wirkt sofort für alle. Stattdessen Bestätigungsdialog,
 * gesperrter Knopf mit wechselnder Beschriftung und eine klare Rückmeldung.
 * Siehe docs/09-performance-und-ux.md.
 */
export function RoleRow({
  role,
  levels,
}: {
  role: RoleRowData
  levels: { level: number; name: string }[]
}) {
  const [clearanceLevel, setClearanceLevel] = useState(role.clearanceLevel)
  const [grantsMembership, setGrantsMembership] = useState(role.grantsMembership)
  const [category, setCategory] = useState(role.category)
  const [permissions, setPermissions] = useState<string[]>(role.permissions)
  const [saved, setSaved] = useState(false)
  const [error, setError] = useState<string | null>(null)
  const [pending, startTransition] = useTransition()

  const dirty =
    clearanceLevel !== role.clearanceLevel ||
    grantsMembership !== role.grantsMembership ||
    category !== role.category ||
    permissions.slice().sort().join() !== role.permissions.slice().sort().join()

  function toggle(permission: Permission, on: boolean) {
    setPermissions((current) =>
      on ? [...current, permission] : current.filter((p) => p !== permission),
    )
    setSaved(false)
  }

  function submit() {
    if (!confirm(roleAdminText.confirm)) return
    setError(null)
    startTransition(async () => {
      const result = await saveRoleMapping({
        discordRoleId: role.discordRoleId,
        clearanceLevel,
        grantsMembership,
        category,
        permissions,
      })
      if (result.ok) {
        setSaved(true)
      } else {
        setError(result.error)
      }
    })
  }

  return (
    <div className="border-b border-line py-5">
      <div className="flex flex-wrap items-baseline gap-x-3 gap-y-1">
        <h3 className="font-condensed">{role.label}</h3>
        <span className="font-mono text-2xs text-text-dim">{role.discordRoleId}</span>
        {!role.isPresent ? (
          <span className="font-condensed text-2xs text-stamp-4">
            {roleAdminText.missingFromGuild}
          </span>
        ) : null}
      </div>

      <div className="mt-3 flex flex-wrap gap-x-8 gap-y-3 text-xs">
        <label className="field-row">
          <span className="font-condensed text-text-dim">{roleAdminText.category}</span>
          <select
            value={category}
            onChange={(event) => {
              setCategory(event.target.value)
              setSaved(false)
            }}
            className="field"
          >
            {CATEGORIES.map((value) => (
              <option key={value} value={value}>
                {roleAdminText.categories[value]}
              </option>
            ))}
          </select>
        </label>

        <label className="field-row">
          <span className="font-condensed text-text-dim">{roleAdminText.clearance}</span>
          <select
            value={clearanceLevel}
            onChange={(event) => {
              setClearanceLevel(Number(event.target.value))
              setSaved(false)
            }}
            className="field"
          >
            {levels.map((level) => (
              <option key={level.level} value={level.level}>
                {level.level} · {level.name}
              </option>
            ))}
          </select>
        </label>

        <label className="flex items-center gap-2">
          <input
            type="checkbox"
            checked={grantsMembership}
            onChange={(event) => {
              setGrantsMembership(event.target.checked)
              setSaved(false)
            }}
          />
          <span className="font-condensed text-text-dim">{roleAdminText.grantsMembership}</span>
        </label>
      </div>

      <fieldset className="mt-4">
        <legend className="text-xs text-text-dim">{roleAdminText.permissions}</legend>
        <div className="mt-2 grid grid-cols-[repeat(auto-fill,minmax(13rem,1fr))] gap-x-4 gap-y-1.5">
          {PERMISSIONS.map((permission) => {
            const optIn = OPT_IN_PERMISSIONS.includes(permission)
            return (
              <label
                key={permission}
                className="flex items-center gap-2 font-mono text-2xs"
                title={optIn ? roleAdminText.optIn : undefined}
              >
                <input
                  type="checkbox"
                  checked={permissions.includes(permission)}
                  onChange={(event) => toggle(permission, event.target.checked)}
                />
                <span className={optIn ? 'text-stamp-3' : undefined}>{permission}</span>
              </label>
            )
          })}
        </div>
      </fieldset>

      <div className="mt-4 flex items-center gap-3">
        <button
          type="button"
          onClick={submit}
          disabled={pending || !dirty}
          className="btn btn-primary"
        >
          {pending ? roleAdminText.saving : roleAdminText.save}
        </button>
        {saved && !dirty ? (
          <span className="font-condensed text-2xs text-text-dim">{roleAdminText.saved}</span>
        ) : null}
        {error ? <span className="font-condensed text-2xs text-stamp-4">{error}</span> : null}
      </div>
    </div>
  )
}