import { useMemo, useState } from 'react'
import { useNavigate } from 'react-router-dom'
import { GameGrid, RulesConfiguration, StepIndicator } from '../components'
import { useGames, useGameRoutes } from '../hooks/useGames'
import { useCreateRun, useRuns, useNamingCategories } from '../hooks/useRuns'
import type { Game, NuzlockeRules, RunVisibility } from '../types'
import { DEFAULT_RULES } from '../types'
import { RULE_DEFINITIONS } from '../types/rules'

const DEFAULT_COLOR = '#6366f1'

export function NewRun() {
  const navigate = useNavigate()
  const { data: games, isLoading, error } = useGames()
  const { data: runs } = useRuns()
  const createRun = useCreateRun()
  const { data: namingCategories } = useNamingCategories()

  const [step, setStep] = useState(1)
  const [selectedGame, setSelectedGame] = useState<Game | null>(null)
  const [rules, setRules] = useState<NuzlockeRules>(DEFAULT_RULES)
  const [runName, setRunName] = useState('')
  const [namingScheme, setNamingScheme] = useState<string | null>(null)
  const [visibility, setVisibility] = useState<RunVisibility>('public')
  const { data: routes } = useGameRoutes(selectedGame?.id ?? null)

  const hiddenRules = useMemo(() => {
    const hidden = new Set<keyof NuzlockeRules>()
    const hasPinwheelZones = routes?.some((r) => r.pinwheelZone != null)
    if (!hasPinwheelZones) {
      hidden.add('pinwheelClause')
    }
    return hidden.size > 0 ? hidden : undefined
  }, [routes])

  const handleGameSelect = (game: Game) => {
    if (selectedGame?.id === game.id) {
      setSelectedGame(null)
      return
    }
    setSelectedGame(game)
    if (!runName || runName === `${selectedGame?.name} Nuzlocke`) {
      setRunName(`${game.name} Nuzlocke`)
    }
  }

  const handleCreate = () => {
    if (!selectedGame) return
    createRun.mutate(
      { gameId: selectedGame.id, name: runName, rules, namingScheme, visibility },
      { onSuccess: (data) => navigate(`/runs/${data.id}`) }
    )
  }

  const visibleRuleKeys = RULE_DEFINITIONS.filter((r) => !hiddenRules?.has(r.key)).map((r) => r.key)
  const enabledRuleCount = visibleRuleKeys.filter((k) => rules[k]).length
  const totalRuleCount = visibleRuleKeys.length

  return (
    <div className="max-w-4xl mx-auto p-8">
      <h1 className="text-3xl font-bold text-text-primary mb-2">New Nuzlocke Run</h1>
      <p className="text-text-tertiary mb-6">Set up your run in a few steps.</p>

      <StepIndicator currentStep={step} onStepClick={setStep} />

      {step === 1 && (
        <div>
          <h2 className="text-xl font-semibold text-text-primary mb-4">Choose a Game</h2>

          <div className="sticky top-0 z-10 bg-surface-0 py-3 mb-4 border-b border-border-default">
            {selectedGame ? (
              <div className="flex items-center justify-between">
                <div className="flex items-center gap-3">
                  <SelectedGameThumb game={selectedGame} />
                  <div>
                    <p className="font-medium text-text-primary">{selectedGame.name}</p>
                    <p className="text-sm text-text-tertiary">
                      {selectedGame.region.charAt(0).toUpperCase() + selectedGame.region.slice(1)}
                    </p>
                  </div>
                </div>
                <button
                  type="button"
                  onClick={() => setStep(2)}
                  className="px-6 py-2 bg-blue-600 text-white rounded-lg font-medium hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-accent-400 focus:ring-offset-2 transition-colors"
                >
                  Next
                </button>
              </div>
            ) : (
              <div className="flex items-center justify-between">
                <p className="text-sm text-text-tertiary">Select a game to continue</p>
                <button
                  type="button"
                  disabled
                  className="px-6 py-2 bg-blue-600 text-white rounded-lg font-medium disabled:opacity-50 disabled:cursor-not-allowed transition-colors"
                >
                  Next
                </button>
              </div>
            )}
          </div>

          {isLoading && (
            <div className="flex items-center justify-center py-12">
              <div className="w-8 h-8 border-4 border-blue-600 border-t-transparent rounded-full animate-spin" />
            </div>
          )}

          {error && (
            <div className="rounded-lg bg-status-failed-bg p-4 text-status-failed">
              Failed to load games. Please try again.
            </div>
          )}

          {games && (
            <GameGrid
              games={games}
              selectedId={selectedGame?.id ?? null}
              onSelect={handleGameSelect}
              runs={runs}
            />
          )}
        </div>
      )}

      {step === 2 && (
        <div>
          <RulesConfiguration rules={rules} onChange={setRules} hiddenRules={hiddenRules} />

          <div className="mt-6 flex justify-between">
            <button
              type="button"
              onClick={() => setStep(1)}
              className="px-6 py-2 text-text-secondary bg-surface-2 rounded-lg font-medium hover:bg-surface-3 focus:outline-none focus:ring-2 focus:ring-gray-400 focus:ring-offset-2 transition-colors"
            >
              Back
            </button>
            <button
              type="button"
              onClick={() => setStep(3)}
              className="px-6 py-2 bg-blue-600 text-white rounded-lg font-medium hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-accent-400 focus:ring-offset-2 transition-colors"
            >
              Next
            </button>
          </div>
        </div>
      )}

      {step === 3 && (
        <div>
          <h2 className="text-xl font-semibold text-text-primary mb-4">Name Your Run</h2>

          <div className="bg-surface-1 rounded-lg shadow p-6 space-y-4">
            <div>
              <label
                htmlFor="run-name"
                className="block text-sm font-medium text-text-secondary mb-1"
              >
                Run Name
              </label>
              <input
                id="run-name"
                type="text"
                value={runName}
                onChange={(e) => setRunName(e.target.value)}
                className="w-full px-3 py-2 rounded-lg border border-border-default bg-surface-2 text-text-primary focus:outline-none focus:ring-2 focus:ring-accent-400 focus:border-transparent"
                placeholder="My Nuzlocke Run"
              />
            </div>

            {namingCategories && namingCategories.length > 0 && (
              <div>
                <label
                  htmlFor="naming-scheme"
                  className="block text-sm font-medium text-text-secondary mb-1"
                >
                  Naming Scheme
                </label>
                <select
                  id="naming-scheme"
                  value={namingScheme ?? ''}
                  onChange={(e) => setNamingScheme(e.target.value || null)}
                  className="w-full px-3 py-2 rounded-lg border border-border-default bg-surface-2 text-text-primary focus:outline-none focus:ring-2 focus:ring-accent-400 focus:border-transparent"
                >
                  <option value="">None (manual nicknames)</option>
                  {namingCategories.map((cat) => (
                    <option key={cat} value={cat}>
                      {cat.charAt(0).toUpperCase() + cat.slice(1)}
                    </option>
                  ))}
                </select>
                <p className="mt-1 text-xs text-text-tertiary">
                  Get nickname suggestions from a themed word list when catching Pokemon.
                </p>
              </div>
            )}

            <div>
              <label
                htmlFor="visibility"
                className="block text-sm font-medium text-text-secondary mb-1"
              >
                Visibility
              </label>
              <select
                id="visibility"
                value={visibility}
                onChange={(e) => setVisibility(e.target.value as RunVisibility)}
                className="w-full px-3 py-2 rounded-lg border border-border-default bg-surface-2 text-text-primary focus:outline-none focus:ring-2 focus:ring-accent-400 focus:border-transparent"
              >
                <option value="public">Public</option>
                <option value="private">Private</option>
              </select>
              <p className="mt-1 text-xs text-text-tertiary">
                {visibility === 'private'
                  ? 'Only you will be able to see this run'
                  : 'Anyone can view this run'}
              </p>
            </div>

            <div className="border-t border-border-default pt-4">
              <h3 className="text-sm font-medium text-text-tertiary mb-2">Summary</h3>
              <dl className="space-y-1 text-sm">
                <div className="flex justify-between">
                  <dt className="text-text-tertiary">Game</dt>
                  <dd className="text-text-primary font-medium">{selectedGame?.name}</dd>
                </div>
                <div className="flex justify-between">
                  <dt className="text-text-tertiary">Region</dt>
                  <dd className="text-text-primary font-medium">
                    {selectedGame &&
                      selectedGame.region.charAt(0).toUpperCase() + selectedGame.region.slice(1)}
                  </dd>
                </div>
                <div className="flex justify-between">
                  <dt className="text-text-tertiary">Rules</dt>
                  <dd className="text-text-primary font-medium">
                    {enabledRuleCount} of {totalRuleCount} enabled
                  </dd>
                </div>
                <div className="flex justify-between">
                  <dt className="text-text-tertiary">Naming Scheme</dt>
                  <dd className="text-text-primary font-medium">
                    {namingScheme
                      ? namingScheme.charAt(0).toUpperCase() + namingScheme.slice(1)
                      : 'None'}
                  </dd>
                </div>
                <div className="flex justify-between">
                  <dt className="text-text-tertiary">Visibility</dt>
                  <dd className="text-text-primary font-medium capitalize">{visibility}</dd>
                </div>
              </dl>
            </div>
          </div>

          {createRun.error && (
            <div className="mt-4 rounded-lg bg-status-failed-bg p-4 text-status-failed">
              Failed to create run. Please try again.
            </div>
          )}

          <div className="mt-6 flex justify-between">
            <button
              type="button"
              onClick={() => setStep(2)}
              className="px-6 py-2 text-text-secondary bg-surface-2 rounded-lg font-medium hover:bg-surface-3 focus:outline-none focus:ring-2 focus:ring-gray-400 focus:ring-offset-2 transition-colors"
            >
              Back
            </button>
            <button
              type="button"
              disabled={!runName.trim() || createRun.isPending}
              onClick={handleCreate}
              className="px-6 py-2 bg-blue-600 text-white rounded-lg font-medium hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-accent-400 focus:ring-offset-2 disabled:opacity-50 disabled:cursor-not-allowed transition-colors"
            >
              {createRun.isPending ? 'Creating...' : 'Create Run'}
            </button>
          </div>
        </div>
      )}
    </div>
  )
}

function SelectedGameThumb({ game }: { game: Game }) {
  const [imgIdx, setImgIdx] = useState(0)
  const backgroundColor = game.color ?? DEFAULT_COLOR
  const boxArtSrcs = [`/boxart/${game.slug}.png`, `/boxart/${game.slug}.jpg`]

  if (imgIdx >= boxArtSrcs.length) {
    return (
      <div
        className="w-10 h-10 rounded flex items-center justify-center flex-shrink-0"
        style={{ backgroundColor }}
      >
        <span className="text-white text-xs font-bold drop-shadow-md">
          {game.name.replace('Pokemon ', '').slice(0, 3)}
        </span>
      </div>
    )
  }

  return (
    <img
      src={boxArtSrcs[imgIdx]}
      alt={game.name}
      className="w-10 h-10 rounded object-cover flex-shrink-0"
      onError={() => setImgIdx((i) => i + 1)}
    />
  )
}