import React, { useEffect, useState } from 'react';
import {
  View,
  Text,
  ScrollView,
  TouchableOpacity,
  Modal,
  Image,
  ActivityIndicator,
  SafeAreaView,
} from 'react-native';
import Pdf from 'react-native-pdf';
import { useAppTheme } from '@theme';
import { ScreenHeader } from '@components';
import { ClipboardIcon, CloseIcon, ChevronRightIcon } from '@icons';
import { useNavigation } from '@react-navigation/native';
import { getFullUrl, isPdf } from '@utils/helper';
import { getStyles } from './documentsScreen.styles';
import { KycDocUploadResponseDocument } from '@interfaces';
import { formatDate } from '@utils/formatters';
import { useAppDispatch, useAppSelector } from '@store';
import { fetchMyKyc } from '../kycScreen';

export const DocumentsScreen: React.FC = () => {
  const { colors } = useAppTheme();
  const styles = getStyles(colors);
  const navigation = useNavigation();
  const dispatch = useAppDispatch();

  const [selectedDoc, setSelectedDoc] =
    useState<KycDocUploadResponseDocument | null>(null);
  const [isModalLoading, setIsModalLoading] = useState<boolean>(true);
  const { myKycResponse } = useAppSelector(state => state.kyc);

  useEffect(() => {
    dispatch(fetchMyKyc());
  }, []);

  const getStatusBadgeConfig = (status: string) => {
    switch (status?.toUpperCase()) {
      case 'APPROVED':
      case 'VERIFIED':
        return {
          bg: colors.successLight,
          text: colors.success,
          label: 'APPROVED',
        };
      case 'PENDING':
        return {
          bg: colors.warningLight,
          text: colors.warning,
          label: 'PENDING',
        };
      case 'REJECTED':
        return {
          bg: colors.errorLight,
          text: colors.error,
          label: 'REJECTED',
        };
      default:
        return {
          bg: colors.primaryLight,
          text: colors.primary,
          label: status?.toUpperCase() || 'ACTIVE',
        };
    }
  };

  const handleOpenDocModal = (doc: KycDocUploadResponseDocument) => {
    setIsModalLoading(true);
    setSelectedDoc(doc);
  };

  const approvedCount = myKycResponse?.documents?.filter(
    d => d.status === 'APPROVED',
  ).length;

  return (
    <View style={styles.container}>
      {/* Screen Header */}
      <ScreenHeader
        title="My Documents"
        showBack={true}
        onBack={() => navigation.goBack()}
      />

      <ScrollView
        contentContainerStyle={styles.scrollContainer}
        showsVerticalScrollIndicator={false}
      >
        {/* Document Status Overview Banner */}
        <View style={styles.summaryCard}>
          <View style={styles.summaryLeft}>
            <Text style={styles.summaryTitle}>Document Verification</Text>
            <Text style={styles.summarySub}>
              {approvedCount} of {myKycResponse?.documents?.length} Documents
              Verified
            </Text>
          </View>
          <View style={styles.summaryBadge}>
            <Text style={styles.summaryBadgeText}>
              {approvedCount === myKycResponse?.documents?.length
                ? 'VERIFIED'
                : 'PENDING'}
            </Text>
          </View>
        </View>

        <Text style={styles.sectionTitle}>Uploaded Documents</Text>

        {myKycResponse?.documents?.length === 0 ? (
          <View style={styles.emptyContainer}>
            <ClipboardIcon size={48} color={colors.placeholder} />
            <Text style={styles.emptyTitle}>No Documents Found</Text>
            <Text style={styles.emptySub}>
              Your uploaded documents will appear here.
            </Text>
          </View>
        ) : (
          myKycResponse?.documents?.map(doc => {
            const statusConfig = getStatusBadgeConfig(doc.status);
            const formattedDocName =
              doc.documentType === 'Pan' ? 'PAN Card' : doc.documentType;

            return (
              <TouchableOpacity
                key={doc.id}
                style={styles.docCard}
                activeOpacity={0.7}
                onPress={() => handleOpenDocModal(doc)}
              >
                {/* Header Row */}
                <View style={styles.cardHeader}>
                  <View style={styles.cardHeaderLeft}>
                    <View style={styles.iconContainer}>
                      <ClipboardIcon size={22} color={colors.primary} />
                    </View>
                    <View style={styles.docTypeContainer}>
                      <Text style={styles.docTitle} numberOfLines={1}>
                        {formattedDocName}
                      </Text>
                      <Text style={styles.docNumber}>
                        Doc #: {doc.documentNumber}
                      </Text>
                    </View>
                  </View>

                  <View
                    style={[
                      styles.statusBadge,
                      { backgroundColor: statusConfig.bg },
                    ]}
                  >
                    <Text
                      style={[styles.statusText, { color: statusConfig.text }]}
                    >
                      {statusConfig.label}
                    </Text>
                  </View>
                </View>

                {/* Details Section */}
                <View style={styles.detailsRow}>
                  <View style={styles.detailItem}>
                    <Text style={styles.detailLabel}>Uploaded On</Text>
                    <Text style={styles.detailValue}>
                      {formatDate(doc.createdAt)}
                    </Text>
                  </View>

                  {doc.verifiedAt && (
                    <View style={styles.detailItem}>
                      <Text style={styles.detailLabel}>Verified On</Text>
                      <Text style={styles.detailValue}>
                        {formatDate(doc.verifiedAt)}
                      </Text>
                    </View>
                  )}
                </View>

                <View style={styles.divider} />

                {/* View Button Footer */}
                <View style={styles.viewButton}>
                  <Text style={styles.viewButtonText}>View Document</Text>
                  <ChevronRightIcon size={16} color={colors.primary} />
                </View>
              </TouchableOpacity>
            );
          })
        )}
      </ScrollView>

      {/* Full Screen View Modal */}
      <Modal
        visible={!!selectedDoc}
        animationType="slide"
        statusBarTranslucent
        onRequestClose={() => setSelectedDoc(null)}
      >
        <View style={styles.modalContainer}>
          {/* Modal Header */}
          <View style={styles.modalHeader}>
            <View style={styles.modalHeaderInfo}>
              <Text style={styles.modalTitle} numberOfLines={1}>
                {selectedDoc?.documentType === 'Pan'
                  ? 'PAN Card'
                  : selectedDoc?.documentType}{' '}
                Preview
              </Text>
              <Text style={styles.modalSubtitle} numberOfLines={1}>
                {selectedDoc?.fileName}
              </Text>
            </View>

            <TouchableOpacity
              style={styles.closeButton}
              activeOpacity={0.7}
              onPress={() => setSelectedDoc(null)}
            >
              <CloseIcon size={20} color={colors.text} />
            </TouchableOpacity>
          </View>

          {/* Modal Body / Viewer */}
          <View style={styles.viewerContainer}>
            {isModalLoading && (
              <View style={styles.loadingContainer}>
                <ActivityIndicator size="large" color={colors.primary} />
                <Text style={styles.loadingText}>Loading file preview...</Text>
              </View>
            )}

            {selectedDoc &&
            isPdf(selectedDoc.fileName || selectedDoc.fileUrl) ? (
              <Pdf
                trustAllCerts={false}
                source={{
                  uri: getFullUrl(selectedDoc.fileUrl),
                  cache: true,
                }}
                onLoadComplete={() => setIsModalLoading(false)}
                onError={error => {
                  setIsModalLoading(false);
                  console.log('PDF Load Error:', error);
                }}
                style={styles.pdfViewer}
              />
            ) : (
              selectedDoc && (
                <Image
                  source={{ uri: getFullUrl(selectedDoc.fileUrl) }}
                  style={styles.imageViewer}
                  resizeMode="contain"
                  onLoadStart={() => setIsModalLoading(true)}
                  onLoadEnd={() => setIsModalLoading(false)}
                  onError={() => setIsModalLoading(false)}
                />
              )
            )}
          </View>
        </View>
      </Modal>
    </View>
  );
};

export default DocumentsScreen;