/**
 * TabataFit Home Screen - Premium Redesign
 * React Native UI with glassmorphism
 */

import { View, StyleSheet, ScrollView, Pressable, Dimensions, Text as RNText } from 'react-native'
import { useRouter } from 'expo-router'
import { useSafeAreaInsets } from 'react-native-safe-area-context'
import { LinearGradient } from 'expo-linear-gradient'
import { BlurView } from 'expo-blur'
import Ionicons from '@expo/vector-icons/Ionicons'

import { useMemo, useState } from 'react'
import { useTranslation } from 'react-i18next'
import { useHaptics, useFeaturedWorkouts, usePopularWorkouts, useCollections } from '@/src/shared/hooks'
import { useUserStore, useActivityStore } from '@/src/shared/stores'
import { StyledText } from '@/src/shared/components/StyledText'
import { WorkoutCard } from '@/src/shared/components/WorkoutCard'
import { CollectionCard } from '@/src/shared/components/CollectionCard'
import { WorkoutCardSkeleton, CollectionCardSkeleton, StatsCardSkeleton } from '@/src/shared/components/loading/Skeleton'

import { useThemeColors, BRAND, GRADIENTS } from '@/src/shared/theme'
import type { ThemeColors } from '@/src/shared/theme/types'
import { SPACING, LAYOUT } from '@/src/shared/constants/spacing'
import { RADIUS } from '@/src/shared/constants/borderRadius'
import type { WorkoutCategory } from '@/src/shared/types'

const { width: SCREEN_WIDTH } = Dimensions.get('window')

const FONTS = {
  LARGE_TITLE: 34,
  TITLE: 28,
  TITLE_2: 22,
  HEADLINE: 17,
  SUBHEADLINE: 15,
  CAPTION_1: 12,
  CAPTION_2: 11,
}

const CATEGORIES: { id: WorkoutCategory | 'all'; key: string }[] = [
  { id: 'all', key: 'all' },
  { id: 'full-body', key: 'fullBody' },
  { id: 'core', key: 'core' },
  { id: 'upper-body', key: 'upperBody' },
  { id: 'lower-body', key: 'lowerBody' },
  { id: 'cardio', key: 'cardio' },
]

// ═══════════════════════════════════════════════════════════════════════════
// MAIN SCREEN
// ═══════════════════════════════════════════════════════════════════════════

export default function HomeScreen() {
  const { t } = useTranslation()
  const insets = useSafeAreaInsets()
  const router = useRouter()
  const haptics = useHaptics()
  const colors = useThemeColors()
  const styles = useMemo(() => createStyles(colors), [colors])
  const userName = useUserStore((s) => s.profile.name)
  const history = useActivityStore((s) => s.history)
  const recentWorkouts = useMemo(() => history.slice(0, 3), [history])

  const [selectedCategory, setSelectedCategory] = useState<WorkoutCategory | 'all'>('all')

  // React Query hooks for live data
  const { data: featuredWorkouts = [], isLoading: isLoadingFeatured } = useFeaturedWorkouts()
  const { data: popularWorkouts = [], isLoading: isLoadingPopular } = usePopularWorkouts(6)
  const { data: collections = [], isLoading: isLoadingCollections } = useCollections()
  
  const featured = featuredWorkouts[0]
  
  const filteredWorkouts = useMemo(() => {
    if (selectedCategory === 'all') return popularWorkouts
    return popularWorkouts.filter((w) => w.category === selectedCategory)
  }, [popularWorkouts, selectedCategory])

  const greeting = (() => {
    const hour = new Date().getHours()
    if (hour < 12) return t('greetings.morning')
    if (hour < 18) return t('greetings.afternoon')
    return t('greetings.evening')
  })()

  const handleWorkoutPress = (id: string) => {
    haptics.buttonTap()
    router.push(`/workout/${id}`)
  }

  const handleCollectionPress = (id: string) => {
    haptics.buttonTap()
    router.push(`/collection/${id}`)
  }

  return (
    <View style={[styles.container, { paddingTop: insets.top }]}>
      <ScrollView
        style={styles.scrollView}
        contentContainerStyle={[styles.scrollContent, { paddingBottom: insets.bottom + 100 }]}
        showsVerticalScrollIndicator={false}
      >
        {/* Hero Section */}
        <View style={styles.heroSection}>
          <StyledText size={FONTS.SUBHEADLINE} color={colors.text.tertiary}>
            {greeting}
          </StyledText>
          <View style={styles.heroHeader}>
            <StyledText
              size={FONTS.LARGE_TITLE}
              weight="bold"
              color={colors.text.primary}
              style={styles.heroTitle}
            >
              {userName}
            </StyledText>
            <Pressable style={styles.profileButton}>
              <Ionicons name="person-circle-outline" size={40} color={colors.text.primary} />
            </Pressable>
          </View>
        </View>

        {/* Featured Workout */}
        <View style={styles.section}>
          <View style={styles.sectionHeader}>
            <StyledText size={FONTS.TITLE_2} weight="semibold" color={colors.text.primary}>
              {t('screens:home.featured')}
            </StyledText>
          </View>
          {isLoadingFeatured ? (
            <WorkoutCardSkeleton />
          ) : featured ? (
            <WorkoutCard
              workout={featured}
              variant="featured"
              onPress={() => handleWorkoutPress(featured.id)}
            />
          ) : null}
        </View>

        {/* Category Filter */}
        <View style={styles.section}>
          <ScrollView
            horizontal
            showsHorizontalScrollIndicator={false}
            contentContainerStyle={styles.categoriesScroll}
          >
            {CATEGORIES.map((cat) => (
              <Pressable
                key={cat.id}
                style={[
                  styles.categoryChip,
                  selectedCategory === cat.id && styles.categoryChipActive,
                ]}
                onPress={() => {
                  haptics.buttonTap()
                  setSelectedCategory(cat.id)
                }}
              >
                {selectedCategory === cat.id && (
                  <BlurView
                    intensity={colors.glass.blurMedium}
                    tint={colors.glass.blurTint}
                    style={StyleSheet.absoluteFill}
                  />
                )}
                <StyledText
                  size={14}
                  weight={selectedCategory === cat.id ? 'semibold' : 'medium'}
                  color={selectedCategory === cat.id ? colors.text.primary : colors.text.secondary}
                >
                  {t(`categories.${cat.key}`)}
                </StyledText>
              </Pressable>
            ))}
          </ScrollView>
        </View>

        {/* Popular Workouts - Horizontal */}
        <View style={styles.section}>
          <View style={styles.sectionHeader}>
            <StyledText size={FONTS.TITLE_2} weight="semibold" color={colors.text.primary}>
              {t('screens:home.popularThisWeek')}
            </StyledText>
            <Pressable hitSlop={8}>
              <StyledText size={FONTS.SUBHEADLINE} color={BRAND.PRIMARY} weight="medium">
                {t('seeAll')}
              </StyledText>
            </Pressable>
          </View>
          <ScrollView
            horizontal
            showsHorizontalScrollIndicator={false}
            contentContainerStyle={styles.workoutsScroll}
          >
            {isLoadingPopular ? (
              // Loading skeletons
              <>
                <WorkoutCardSkeleton />
                <WorkoutCardSkeleton />
                <WorkoutCardSkeleton />
              </>
            ) : (
              filteredWorkouts.map((workout: any) => (
                <WorkoutCard
                  key={workout.id}
                  workout={workout}
                  variant="horizontal"
                  onPress={() => handleWorkoutPress(workout.id)}
                />
              ))
            )}
          </ScrollView>
        </View>

        {/* Collections Grid */}
        <View style={styles.section}>
          <View style={styles.sectionHeader}>
            <StyledText size={FONTS.TITLE_2} weight="semibold" color={colors.text.primary}>
              {t('screens:home.collections')}
            </StyledText>
          </View>
          <View style={styles.collectionsGrid}>
            {isLoadingCollections ? (
              // Loading skeletons for collections
              <>
                <CollectionCardSkeleton />
                <CollectionCardSkeleton />
              </>
            ) : (
              collections.map((collection) => (
                <CollectionCard
                  key={collection.id}
                  collection={collection}
                  onPress={() => handleCollectionPress(collection.id)}
                />
              ))
            )}
          </View>
        </View>
      </ScrollView>
    </View>
  )
}

// ═══════════════════════════════════════════════════════════════════════════
// STYLES
// ═══════════════════════════════════════════════════════════════════════════

function createStyles(colors: ThemeColors) {
  return StyleSheet.create({
    container: {
      flex: 1,
      backgroundColor: colors.bg.base,
    },
    scrollView: {
      flex: 1,
    },
    scrollContent: {
      paddingHorizontal: LAYOUT.SCREEN_PADDING,
    },

    // Hero Section
    heroSection: {
      marginBottom: SPACING[6],
    },
    heroHeader: {
      flexDirection: 'row',
      justifyContent: 'space-between',
      alignItems: 'center',
      marginTop: SPACING[2],
    },
    heroTitle: {
      flex: 1,
      marginRight: SPACING[3],
    },
    profileButton: {
      width: 44,
      height: 44,
      alignItems: 'center',
      justifyContent: 'center',
    },

    // Sections
    section: {
      marginBottom: SPACING[8],
    },
    sectionHeader: {
      flexDirection: 'row',
      justifyContent: 'space-between',
      alignItems: 'center',
      marginBottom: SPACING[4],
    },

    // Categories
    categoriesScroll: {
      gap: SPACING[2],
      paddingRight: SPACING[4],
    },
    categoryChip: {
      paddingHorizontal: SPACING[4],
      paddingVertical: SPACING[2],
      borderRadius: RADIUS.FULL,
      overflow: 'hidden',
      borderWidth: 1,
      borderColor: colors.border.glass,
    },
    categoryChipActive: {
      borderColor: BRAND.PRIMARY,
      backgroundColor: `${BRAND.PRIMARY}30`,
    },

    // Workouts Scroll
    workoutsScroll: {
      gap: SPACING[3],
      paddingRight: SPACING[4],
    },

    // Collections Grid
    collectionsGrid: {
      flexDirection: 'row',
      flexWrap: 'wrap',
      gap: SPACING[3],
    },
  })
}