import React, { useState } from 'react';
import {
  View, Text, ScrollView, TouchableOpacity, TextInput, StyleSheet, Alert,
} from 'react-native';
import { useRouter } from 'expo-router';
import { useForm, Controller } from 'react-hook-form';
import { zodResolver } from '@hookform/resolvers/zod';
import { z } from 'zod';
import { Ionicons } from '@expo/vector-icons';
import { SafeAreaView } from 'react-native-safe-area-context';
import { usePresetStore } from '@store/presetStore';
import { useFilamentStore } from '@store/filamentStore';
import { Input } from '@presentation/components/ui/Input';
import { Button } from '@presentation/components/ui/Button';
import { Card } from '@presentation/components/ui/Card';
import { calcNetWeight } from '@domain/Filament';
import { colors, typography, spacing, radius } from '@shared/theme';
import { MATERIALS, type Material } from '@shared/constants';
import { formatWeight } from '@shared/utils/filament';

const schema = z.object({
  brand: z.string().min(1, 'Marca obrigatória'),
  model: z.string().optional(),
  totalWeightG: z.coerce.number().min(1, 'Informe o peso total'),
  tempHotendC: z.coerce.number().optional(),
  tempBedC: z.coerce.number().optional(),
  flowFactorPct: z.coerce.number().optional(),
  notes: z.string().optional(),
});

type FormData = z.infer<typeof schema>;

const PRESET_COLORS = ['#E05533', '#2563EB', '#FFFFFF', '#1E1B18', '#22C55E', '#EAB308', '#EC4899', '#A855F7', '#F97316'];

/**
 * Tela de Cadastro de Filamento — 2X-0
 */
export default function NewFilamentScreen(): React.ReactElement {
  const router = useRouter();
  const { presets, systemPresets } = usePresetStore();
  const { addFilament } = useFilamentStore();

  const [selectedColor, setSelectedColor] = useState('#E05533');
  const [hexInput, setHexInput] = useState('#E05533');
  const [selectedMaterial, setSelectedMaterial] = useState<Material>('PLA');
  const [selectedPresetId, setSelectedPresetId] = useState<string | null>(systemPresets[0]?.id ?? null);
  const [isLoading, setIsLoading] = useState(false);

  const { control, handleSubmit, watch, formState: { errors } } = useForm<FormData>({
    resolver: zodResolver(schema),
    defaultValues: { brand: '', model: '', totalWeightG: 0, tempHotendC: 210, tempBedC: 60, flowFactorPct: 100 },
  });

  const totalWeight = watch('totalWeightG');
  const selectedPreset = presets.find((p) => p.id === selectedPresetId);
  const netWeight = selectedPreset && totalWeight
    ? calcNetWeight(Number(totalWeight), selectedPreset.spoolWeightG)
    : 0;
  const pct = Math.min(100, Math.round((netWeight / 1000) * 100));

  async function onSubmit(data: FormData): Promise<void> {
    if (!selectedPresetId) {
      Alert.alert('Atenção', 'Selecione um preset de carretel.');
      return;
    }
    setIsLoading(true);
    try {
      // TODO: CreateFilamentUseCase via container DI
      console.log('create filament', { ...data, material: selectedMaterial, colorHex: selectedColor, spoolPresetId: selectedPresetId });
      router.back();
    } catch {
      Alert.alert('Erro', 'Não foi possível salvar o filamento.');
    } finally {
      setIsLoading(false);
    }
  }

  return (
    <SafeAreaView style={styles.safe}>
      <ScrollView showsVerticalScrollIndicator={false} keyboardShouldPersistTaps="handled">
        {/* Header */}
        <View style={styles.header}>
          <TouchableOpacity onPress={() => router.back()}>
            <Ionicons name="chevron-back" size={24} color={colors.textPrimary} />
          </TouchableOpacity>
          <Text style={styles.headerTitle}>Novo Filamento</Text>
          <View style={{ width: 24 }} />
        </View>

        <View style={styles.content}>
          {/* Cor */}
          <Text style={styles.sectionLabel}>COR DO FILAMENTO</Text>
          <Card style={styles.colorCard}>
            <View style={styles.colorPreviewRow}>
              <View style={[styles.colorSquare, { backgroundColor: selectedColor }]} />
              <Text style={styles.hexValue}>{hexInput}</Text>
              <TouchableOpacity><Ionicons name="pencil-outline" size={18} color={colors.textSecondary} /></TouchableOpacity>
            </View>
            <View style={styles.colorPalette}>
              {PRESET_COLORS.map((c) => (
                <TouchableOpacity
                  key={c}
                  onPress={() => { setSelectedColor(c); setHexInput(c); }}
                  style={[styles.colorDot, { backgroundColor: c }, selectedColor === c && styles.colorDotActive]}
                />
              ))}
              <TouchableOpacity style={styles.colorAddBtn}>
                <Ionicons name="add" size={18} color={colors.textSecondary} />
              </TouchableOpacity>
            </View>
          </Card>

          {/* Material */}
          <Text style={styles.sectionLabel}>MATERIAL</Text>
          <View style={styles.materialChips}>
            {MATERIALS.map((m) => (
              <TouchableOpacity
                key={m}
                onPress={() => setSelectedMaterial(m)}
                style={[styles.chip, selectedMaterial === m && styles.chipActive]}
              >
                <Text style={[styles.chipText, selectedMaterial === m && styles.chipTextActive]}>{m}</Text>
              </TouchableOpacity>
            ))}
          </View>

          {/* Marca e Modelo */}
          <Controller
            control={control}
            name="brand"
            render={({ field }) => (
              <Input label="MARCA" placeholder="Elegoo" error={errors.brand?.message} onChangeText={field.onChange} value={field.value} />
            )}
          />
          <Controller
            control={control}
            name="model"
            render={({ field }) => (
              <Input label="MODELO (OPCIONAL)" placeholder="Ex: Rapid, Matte, Silk..." onChangeText={field.onChange} value={field.value ?? ''} />
            )}
          />

          {/* Parâmetros de impressão */}
          <Text style={styles.sectionLabel}>PARÂMETROS DE IMPRESSÃO</Text>
          <View style={styles.paramRow}>
            <Controller
              control={control}
              name="tempHotendC"
              render={({ field }) => (
                <View style={styles.paramField}>
                  <Input
                    label="Hotend (°C)"
                    keyboardType="numeric"
                    onChangeText={field.onChange}
                    value={field.value?.toString() ?? ''}
                    leftIcon={<Ionicons name="thermometer-outline" size={16} color={colors.stockLow} />}
                  />
                </View>
              )}
            />
            <Controller
              control={control}
              name="tempBedC"
              render={({ field }) => (
                <View style={styles.paramField}>
                  <Input
                    label="Mesa (°C)"
                    keyboardType="numeric"
                    onChangeText={field.onChange}
                    value={field.value?.toString() ?? ''}
                    leftIcon={<Ionicons name="flag-outline" size={16} color={colors.stockMedium} />}
                  />
                </View>
              )}
            />
            <Controller
              control={control}
              name="flowFactorPct"
              render={({ field }) => (
                <View style={styles.paramField}>
                  <Input
                    label="Fluxo (%)"
                    keyboardType="numeric"
                    onChangeText={field.onChange}
                    value={field.value?.toString() ?? ''}
                    leftIcon={<Ionicons name="time-outline" size={16} color={colors.accent} />}
                  />
                </View>
              )}
            />
          </View>

          {/* Preset */}
          <View style={styles.presetHeader}>
            <Text style={styles.sectionLabel}>PRESET DO CARRETEL</Text>
            <TouchableOpacity onPress={() => router.push('/(app)/config/presets/new')}>
              <Text style={styles.addPresetLink}>+ Personalizado</Text>
            </TouchableOpacity>
          </View>
          {presets.map((p) => (
            <TouchableOpacity
              key={p.id}
              onPress={() => setSelectedPresetId(p.id)}
              style={[styles.presetItem, selectedPresetId === p.id && styles.presetItemActive]}
            >
              <Ionicons name="disc-outline" size={20} color={selectedPresetId === p.id ? colors.accent : colors.textSecondary} />
              <View style={styles.presetInfo}>
                <Text style={[styles.presetName, selectedPresetId === p.id && styles.presetNameActive]}>{p.name}</Text>
                {selectedPresetId === p.id && <Text style={styles.presetSub}>Carretel: {p.spoolWeightG}g</Text>}
              </View>
              <Text style={styles.presetWeight}>{p.spoolWeightG}g</Text>
            </TouchableOpacity>
          ))}

          {/* Calculadora */}
          <Text style={styles.sectionLabel}>CALCULADORA DE PESO</Text>
          <Text style={styles.calcLabel}>Peso Total na Balança (g)</Text>
          <Controller
            control={control}
            name="totalWeightG"
            render={({ field }) => (
              <Card style={styles.calcInput}>
                <Ionicons name="scale-outline" size={20} color={colors.textSecondary} />
                <TextInput
                  style={styles.calcValue}
                  keyboardType="numeric"
                  placeholder="0"
                  placeholderTextColor={colors.textSecondary}
                  onChangeText={field.onChange}
                  value={field.value?.toString() ?? ''}
                />
                <Text style={styles.calcUnit}>g</Text>
              </Card>
            )}
          />

          {netWeight > 0 && (
            <Card style={styles.resultCard}>
              <View style={styles.resultTop}>
                <Text style={styles.resultLabel}>Filamento Disponível</Text>
                <Text style={styles.resultCalc}>{totalWeight}g – {selectedPreset?.spoolWeightG}g</Text>
              </View>
              <View style={styles.resultBottom}>
                <Text style={styles.resultValue}>{formatWeight(netWeight)}</Text>
                <View style={styles.resultPctBadge}>
                  <View style={[styles.resultDot, { backgroundColor: colors.accent }]} />
                  <Text style={styles.resultPct}>{pct}%</Text>
                </View>
              </View>
            </Card>
          )}
        </View>
      </ScrollView>

      {/* CTA fixo */}
      <View style={styles.footer}>
        <Button
          label="Salvar Filamento"
          leftIcon={<Ionicons name="save-outline" size={18} color={colors.bgBase} />}
          onPress={handleSubmit(onSubmit)}
          isLoading={isLoading}
        />
      </View>
    </SafeAreaView>
  );
}

const styles = StyleSheet.create({
  safe: { flex: 1, backgroundColor: colors.bgBase },
  header: { flexDirection: 'row', alignItems: 'center', justifyContent: 'space-between', paddingHorizontal: spacing[5], paddingVertical: spacing[4] },
  headerTitle: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.md, fontWeight: typography.fontWeight.semibold, color: colors.textPrimary },
  content: { paddingHorizontal: spacing[5], gap: spacing[4], paddingBottom: spacing[10] },
  sectionLabel: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.xs, fontWeight: typography.fontWeight.bold, color: colors.textSecondary, letterSpacing: 0.8, textTransform: 'uppercase' },
  colorCard: { gap: spacing[3] },
  colorPreviewRow: { flexDirection: 'row', alignItems: 'center', gap: spacing[3] },
  colorSquare: { width: 40, height: 40, borderRadius: radius.sm },
  hexValue: { flex: 1, fontFamily: typography.fontFamily.mono, fontSize: typography.fontSize.base, color: colors.textPrimary },
  colorPalette: { flexDirection: 'row', flexWrap: 'wrap', gap: spacing[2] },
  colorDot: { width: 32, height: 32, borderRadius: radius.full, borderWidth: 2, borderColor: 'transparent' },
  colorDotActive: { borderColor: colors.accent },
  colorAddBtn: { width: 32, height: 32, borderRadius: radius.full, backgroundColor: colors.bgHover, alignItems: 'center', justifyContent: 'center' },
  materialChips: { flexDirection: 'row', flexWrap: 'wrap', gap: spacing[2] },
  chip: { paddingHorizontal: spacing[4], paddingVertical: spacing[2], borderRadius: radius.full, backgroundColor: colors.bgSurface, borderWidth: 1, borderColor: colors.border },
  chipActive: { backgroundColor: colors.accent, borderColor: colors.accent },
  chipText: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.sm, fontWeight: typography.fontWeight.medium, color: colors.textSecondary },
  chipTextActive: { color: colors.bgBase },
  paramRow: { flexDirection: 'row', gap: spacing[3] },
  paramField: { flex: 1 },
  presetHeader: { flexDirection: 'row', justifyContent: 'space-between', alignItems: 'center' },
  addPresetLink: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.sm, color: colors.accent },
  presetItem: { flexDirection: 'row', alignItems: 'center', gap: spacing[3], backgroundColor: colors.bgSurface, borderRadius: radius.lg, padding: spacing[4], borderWidth: 1, borderColor: colors.border },
  presetItemActive: { borderColor: colors.accent },
  presetInfo: { flex: 1 },
  presetName: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.base, color: colors.textPrimary },
  presetNameActive: { color: colors.accent },
  presetSub: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.xs, color: colors.textSecondary },
  presetWeight: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.sm, color: colors.textSecondary },
  calcLabel: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.sm, color: colors.textSecondary },
  calcInput: { flexDirection: 'row', alignItems: 'center', gap: spacing[3] },
  calcValue: { flex: 1, fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize['2xl'], fontWeight: typography.fontWeight.bold, color: colors.textPrimary },
  calcUnit: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.base, color: colors.textSecondary },
  resultCard: { backgroundColor: colors.bgHover },
  resultTop: { flexDirection: 'row', justifyContent: 'space-between', marginBottom: spacing[2] },
  resultLabel: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.sm, color: colors.textSecondary },
  resultCalc: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.xs, color: colors.textSecondary },
  resultBottom: { flexDirection: 'row', justifyContent: 'space-between', alignItems: 'center' },
  resultValue: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize['2xl'], fontWeight: typography.fontWeight.bold, color: colors.accent },
  resultPctBadge: { flexDirection: 'row', alignItems: 'center', gap: 6, backgroundColor: colors.accentMuted, paddingHorizontal: spacing[3], paddingVertical: 4, borderRadius: radius.sm },
  resultDot: { width: 8, height: 8, borderRadius: radius.full },
  resultPct: { fontFamily: typography.fontFamily.ui, fontSize: typography.fontSize.sm, fontWeight: typography.fontWeight.bold, color: colors.accent },
  footer: { padding: spacing[5], borderTopWidth: 1, borderTopColor: colors.border, backgroundColor: colors.bgBase },
});