/**
 * Checklist Screen
 * ERP Transportistas
 * Sprint S8 - TASK-007
 *
 * Pre-trip checklist screen.
 */

import React, { useEffect, useState } from 'react';
import {
  View,
  Text,
  StyleSheet,
  ScrollView,
  TouchableOpacity,
  ActivityIndicator,
  Alert,
} from 'react-native';
import { useNavigation, useRoute } from '@react-navigation/native';
import type { NativeStackNavigationProp } from '@react-navigation/native-stack';
import type { RouteProp } from '@react-navigation/native';
import { Ionicons } from '@expo/vector-icons';
import { useViajeStore } from '../store';
import type { RootStackParamList, ChecklistItem } from '../types';

type NavigationProp = NativeStackNavigationProp<RootStackParamList>;
type ChecklistRouteProp = RouteProp<RootStackParamList, 'Checklist'>;

export function ChecklistScreen(): JSX.Element {
  const navigation = useNavigation<NavigationProp>();
  const route = useRoute<ChecklistRouteProp>();
  const {
    checklist,
    cargarChecklist,
    completarItemChecklist,
    guardarChecklist,
    isLoading,
  } = useViajeStore();

  const [isSaving, setIsSaving] = useState(false);

  useEffect(() => {
    cargarChecklist(route.params.viajeId);
  }, [route.params.viajeId]);

  const toggleItem = (itemId: string, currentState: boolean): void => {
    completarItemChecklist(itemId, !currentState);
  };

  const allRequiredCompleted = (): boolean => {
    return checklist
      .filter((item) => item.requerido)
      .every((item) => item.completado);
  };

  const handleSave = async (): Promise<void> => {
    if (!allRequiredCompleted()) {
      Alert.alert(
        'Items Pendientes',
        'Debes completar todos los items requeridos antes de continuar'
      );
      return;
    }

    setIsSaving(true);

    try {
      await guardarChecklist();
      Alert.alert('Éxito', 'Checklist guardado correctamente', [
        { text: 'OK', onPress: () => navigation.goBack() },
      ]);
    } catch (error) {
      Alert.alert('Error', 'No se pudo guardar el checklist');
    } finally {
      setIsSaving(false);
    }
  };

  const renderItem = (item: ChecklistItem): JSX.Element => (
    <TouchableOpacity
      key={item.id}
      style={[styles.itemContainer, item.completado && styles.itemCompleted]}
      onPress={() => toggleItem(item.id, item.completado)}
    >
      <View style={styles.itemCheckbox}>
        {item.completado ? (
          <Ionicons name="checkbox" size={28} color="#22c55e" />
        ) : (
          <Ionicons name="square-outline" size={28} color="#94a3b8" />
        )}
      </View>
      <View style={styles.itemContent}>
        <Text style={[styles.itemDescription, item.completado && styles.itemTextCompleted]}>
          {item.descripcion}
        </Text>
        {item.requerido && (
          <Text style={styles.itemRequired}>Requerido</Text>
        )}
      </View>
      {item.foto && (
        <Ionicons name="camera" size={20} color="#3b82f6" />
      )}
    </TouchableOpacity>
  );

  if (isLoading) {
    return (
      <View style={styles.loadingContainer}>
        <ActivityIndicator size="large" color="#2563eb" />
        <Text style={styles.loadingText}>Cargando checklist...</Text>
      </View>
    );
  }

  const completedCount = checklist.filter((item) => item.completado).length;
  const totalCount = checklist.length;
  const progress = totalCount > 0 ? (completedCount / totalCount) * 100 : 0;

  return (
    <View style={styles.container}>
      {/* Progress Header */}
      <View style={styles.header}>
        <Text style={styles.headerTitle}>Checklist Pre-viaje</Text>
        <Text style={styles.headerProgress}>
          {completedCount} de {totalCount} completados
        </Text>
        <View style={styles.progressBar}>
          <View style={[styles.progressFill, { width: `${progress}%` }]} />
        </View>
      </View>

      {/* Checklist Items */}
      <ScrollView style={styles.content}>
        {checklist.length === 0 ? (
          <View style={styles.emptyContainer}>
            <Ionicons name="clipboard-outline" size={48} color="#94a3b8" />
            <Text style={styles.emptyText}>No hay items en el checklist</Text>
          </View>
        ) : (
          checklist.map(renderItem)
        )}
      </ScrollView>

      {/* Save Button */}
      <View style={styles.footer}>
        <TouchableOpacity
          style={[
            styles.saveButton,
            (!allRequiredCompleted() || isSaving) && styles.saveButtonDisabled,
          ]}
          onPress={handleSave}
          disabled={!allRequiredCompleted() || isSaving}
        >
          {isSaving ? (
            <ActivityIndicator color="#ffffff" />
          ) : (
            <>
              <Ionicons name="checkmark-circle" size={24} color="#ffffff" />
              <Text style={styles.saveButtonText}>Guardar y Continuar</Text>
            </>
          )}
        </TouchableOpacity>
      </View>
    </View>
  );
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: '#f1f5f9',
  },
  loadingContainer: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
  },
  loadingText: {
    marginTop: 12,
    fontSize: 16,
    color: '#64748b',
  },
  header: {
    backgroundColor: '#ffffff',
    padding: 16,
    borderBottomWidth: 1,
    borderBottomColor: '#e2e8f0',
  },
  headerTitle: {
    fontSize: 20,
    fontWeight: 'bold',
    color: '#1e293b',
  },
  headerProgress: {
    fontSize: 14,
    color: '#64748b',
    marginTop: 4,
  },
  progressBar: {
    height: 6,
    backgroundColor: '#e2e8f0',
    borderRadius: 3,
    marginTop: 12,
    overflow: 'hidden',
  },
  progressFill: {
    height: '100%',
    backgroundColor: '#22c55e',
    borderRadius: 3,
  },
  content: {
    flex: 1,
    padding: 16,
  },
  emptyContainer: {
    alignItems: 'center',
    paddingVertical: 48,
  },
  emptyText: {
    fontSize: 16,
    color: '#64748b',
    marginTop: 12,
  },
  itemContainer: {
    backgroundColor: '#ffffff',
    borderRadius: 12,
    padding: 16,
    marginBottom: 8,
    flexDirection: 'row',
    alignItems: 'center',
    shadowColor: '#000',
    shadowOffset: { width: 0, height: 1 },
    shadowOpacity: 0.05,
    shadowRadius: 2,
    elevation: 1,
  },
  itemCompleted: {
    backgroundColor: '#f0fdf4',
    borderWidth: 1,
    borderColor: '#bbf7d0',
  },
  itemCheckbox: {
    marginRight: 12,
  },
  itemContent: {
    flex: 1,
  },
  itemDescription: {
    fontSize: 16,
    color: '#1e293b',
  },
  itemTextCompleted: {
    color: '#16a34a',
  },
  itemRequired: {
    fontSize: 12,
    color: '#f59e0b',
    marginTop: 4,
  },
  footer: {
    padding: 16,
    backgroundColor: '#ffffff',
    borderTopWidth: 1,
    borderTopColor: '#e2e8f0',
  },
  saveButton: {
    backgroundColor: '#22c55e',
    borderRadius: 12,
    padding: 16,
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'center',
  },
  saveButtonDisabled: {
    backgroundColor: '#86efac',
  },
  saveButtonText: {
    color: '#ffffff',
    fontSize: 16,
    fontWeight: '600',
    marginLeft: 8,
  },
});