import { router, useLocalSearchParams } from "expo-router";
import { useMemo, useState } from "react";
import { FlatList, Pressable, View } from "react-native";
import { useTranslation } from "react-i18next";
import { Chip, ChipRow } from "@/components/ui/Chip";
import { EmptyState } from "@/components/ui/EmptyState";
import { AppHeader } from "@/components/ui/Header";
import { ProductRow } from "@/components/ui/ProductCard";
import { Screen } from "@/components/ui/Screen";
import { SearchField } from "@/components/ui/SearchField";
import { Text } from "@/components/ui/Text";
import { products, searchProducts } from "@/lib/data/products";
import { categories, routes } from "@/lib/routes";
import { colors, gutter } from "@/lib/theme";

const recent = ["Panadol", "Metformin", "Vitamin C", "Cough syrup", "Glucose meter"];

export default function SearchScreen() {
  const { t } = useTranslation();
  const params = useLocalSearchParams<{ q?: string }>();
  const [q, setQ] = useState(params.q ?? "");

  const results = useMemo(() => (q.trim() ? searchProducts(q) : []), [q]);

  return (
    <Screen>
      <AppHeader title="Search" />
      <View style={{ paddingHorizontal: gutter }}>
        <SearchField
          value={q}
          onChangeText={setQ}
          onClear={() => setQ("")}
          autoFocus
          placeholder={t("common.search")}
        />
      </View>

      {!q.trim() ? (
        <View style={{ paddingHorizontal: gutter, paddingTop: 20 }}>
          <Text variant="h3">Recent searches</Text>
          <View style={{ marginTop: 12, gap: 10 }}>
            {recent.map((term) => (
              <Pressable
                key={term}
                onPress={() => setQ(term)}
                style={{ flexDirection: "row", alignItems: "center", gap: 10 }}
              >
                <Text variant="body" color={colors.muted}>
                  {term}
                </Text>
              </Pressable>
            ))}
          </View>

          <Text variant="h3" style={{ marginTop: 28, marginBottom: 12 }}>
            Browse by category
          </Text>
          <ChipRow gutters={0}>
            {categories.map((c) => (
              <Chip
                key={c.id}
                label={t(c.labelKey)}
                icon={c.icon}
                onPress={() =>
                  router.push({ pathname: routes.shop, params: { category: c.id } })
                }
              />
            ))}
          </ChipRow>

          <Text variant="h3" style={{ marginTop: 28, marginBottom: 12 }}>
            Popular right now
          </Text>
          <View style={{ gap: 10 }}>
            {products
              .filter((p) => p.badge === "bestseller")
              .slice(0, 4)
              .map((p) => (
                <ProductRow key={p.id} product={p} />
              ))}
          </View>
        </View>
      ) : (
        <FlatList
          data={results}
          keyExtractor={(i) => i.id}
          contentContainerStyle={{
            paddingHorizontal: gutter,
            paddingTop: 16,
            paddingBottom: 40,
            gap: 10,
          }}
          ListEmptyComponent={
            <EmptyState
              icon="search-outline"
              title="Nothing found"
              body="Try a brand name, symptom or category."
              compact
            />
          }
          ListHeaderComponent={
            <Text variant="caption" color={colors.subtle} style={{ marginBottom: 8 }}>
              {results.length} result{results.length === 1 ? "" : "s"}
            </Text>
          }
          renderItem={({ item }) => <ProductRow product={item} />}
        />
      )}
    </Screen>
  );
}