"use client";

import { IconSymbol } from "@/components/ui/IconSymbol";
import { getFoods, insertGenAIResult } from "@/services/data/foods";
import { uploadImageToSupabase } from "@/services/data/imageUpload";
import { getProfile } from "@/services/data/profile";
import { callGenAIonImage } from "@/services/gemini";
import { supabase } from "@/services/supabase";
import { Feather, FontAwesome, Ionicons } from "@expo/vector-icons";
import { useQuery } from "@tanstack/react-query";
import * as FileSystem from "expo-file-system";
import * as ImagePicker from "expo-image-picker";
import { router } from "expo-router";
import { useEffect, useMemo, useState } from "react";
import {
  Alert,
  Image,
  SafeAreaView,
  ScrollView,
  StatusBar,
  Text,
  TextInput,
  TouchableOpacity,
  View,
} from "react-native";

const useFoodsQuery = () => {
  return useQuery({
    queryKey: ["highlight-foods"],
    queryFn: async () => {
      const { data, error } = await getFoods(undefined, true, undefined, 4);
      if (error) throw error;
      return data || [];
    },
    staleTime: 1000 * 60 * 5,
  });
};

const useUserProfile = () => {
  const [userId, setUserId] = useState<string | null>(null);
  const [isLoadingUserId, setIsLoadingUserId] = useState(true);

  // Get current user ID
  useEffect(() => {
    const fetchUserId = async () => {
      try {
        const { data, error } = await supabase.auth.getUser();
        if (error) throw error;
        setUserId(data?.user?.id || null);
      } catch (error) {
        console.error("Error fetching user:", error);
      } finally {
        setIsLoadingUserId(false);
      }
    };

    fetchUserId();
  }, []);

  // Fetch user profile data
  const {
    data: profileData,
    isLoading: isLoadingProfile,
    error: profileError,
  } = useQuery({
    queryKey: ["profile", userId],
    queryFn: async () => {
      if (!userId) throw new Error("No user id");
      return getProfile(userId);
    },
    enabled: !!userId,
    staleTime: 1000 * 60 * 5, // 5 minutes
  });

  return {
    userId,
    profileData: profileData?.data,
    isLoading: isLoadingUserId || isLoadingProfile,
    error: profileError,
  };
};

const runImagePipeline = async (
  imageBase64: string,
  imageType: string,
  userId: string
) => {
  const imageUri = await uploadImageToSupabase(imageBase64, imageType, userId);
  const genAIResult = await callGenAIonImage(imageUri);
  if (genAIResult.error) throw genAIResult.error;
  const { data: genAIResultData } = genAIResult;
  if (!genAIResultData) throw new Error("GenAI result is null");
  await insertGenAIResult(genAIResultData, userId, imageUri);
};

const processImage = async (
  asset: ImagePicker.ImagePickerAsset,
  userId: string
) => {
  const base64 = await FileSystem.readAsStringAsync(asset.uri, {
    encoding: "base64",
  });
  const imageType = asset.mimeType || "image/jpeg";
  await runImagePipeline(base64, imageType, userId);
};

const navigateToFoodDetail = (foodId: string) => {
  router.push({ pathname: "/food/[id]", params: { id: foodId } });
};

export default function HomeScreen() {
  const [imageProcessing, setImageProcessing] = useState(false);
  const [searchQuery, setSearchQuery] = useState("");

  const { profileData } = useUserProfile();
  const {
    data: foodsData = [],
    isLoading: isLoadingFoods,
    error: foodsError,
  } = useFoodsQuery();

  const handleImageSelection = async (
    pickerFn:
      | typeof ImagePicker.launchCameraAsync
      | typeof ImagePicker.launchImageLibraryAsync
  ) => {
    const result = await pickerFn({
      mediaTypes: ["images"],
      allowsEditing: true,
      aspect: [1, 1],
      quality: 1,
    });

    if (!result.canceled) {
      setImageProcessing(true);
      try {
        const { data, error } = await supabase.auth.getUser();
        if (error || !data?.user?.id) throw new Error("Cannot get user id");
        const userId = data.user.id;
        await processImage(result.assets[0], userId);
      } catch (err) {
        Alert.alert(
          "Image Processing Failed",
          (err as Error).message || "Unknown error"
        );
      } finally {
        setImageProcessing(false);
      }
      router.push({
        pathname: "/profile",
      });
    }
  };

  const filteredFoods = useMemo(() => {
    return searchQuery
      ? foodsData.filter((food) =>
          food.name.toLowerCase().includes(searchQuery.toLowerCase())
        )
      : foodsData;
  }, [foodsData, searchQuery]);

  // Get username or fallback to a default greeting
  const username = profileData?.username || profileData?.full_name || "Chef";
  const greeting = `Hi! ${username}`;

  return (
    <SafeAreaView className="flex-1 bg-white">
      <StatusBar barStyle="dark-content" />
      {imageProcessing && (
        <View
          style={{
            position: "absolute",
            top: 0,
            left: 0,
            right: 0,
            bottom: 0,
            backgroundColor: "rgba(255,255,255,0.7)",
            zIndex: 9999,
            justifyContent: "center",
            alignItems: "center",
          }}
        >
          <View
            style={{
              backgroundColor: "#fff",
              padding: 24,
              borderRadius: 16,
              alignItems: "center",
            }}
          >
            <Text
              style={{ fontSize: 18, fontWeight: "bold", marginBottom: 12 }}
            >
              Processing image...
            </Text>
            <View style={{ marginBottom: 8 }}>
              <FontAwesome
                name="spinner"
                size={36}
                color="#ffd60a"
                style={{}}
              />
            </View>
            <Text style={{ color: "#888" }}>Please wait</Text>
          </View>
        </View>
      )}

      <View className="flex-row justify-between items-center px-6 pt-4 pb-2">
        <Text className="text-3xl font-bold">{greeting}</Text>
        <View className="bg-[#ffd60a] p-3 rounded-lg">
          <Ionicons name="settings-outline" size={24} color="black" />
        </View>
      </View>

      <ScrollView
        className="flex-1"
        showsVerticalScrollIndicator={false}
        contentContainerStyle={{ paddingBottom: 100 }}
      >
        {/* Main content container with consistent padding */}
        <View className="px-6">
          {/* "Show your dishes" section */}
          <View className="mb-6">
            <View className="flex-row items-center mb-4">
              <Text className="mr-2 text-2xl font-bold">Show your dishes</Text>
              <Feather name="wifi" size={20} color="black" />
            </View>

            <View className="flex-row items-center px-4 py-3 mb-6 bg-white border border-gray-300 rounded-full">
              <TextInput
                className="flex-1"
                placeholder="Search..."
                value={searchQuery}
                onChangeText={setSearchQuery}
              />
              <View className="bg-[#ffd60a] p-2 rounded-full">
                <Feather name="send" size={20} color="black" />
              </View>
            </View>
          </View>

          {/* Upload feature section */}
          <View className="mb-8">
            <View className="flex-row justify-between">
              <TouchableOpacity
                className="bg-[#ffd60a] p-4 rounded-xl w-[48%]"
                onPress={async () => {
                  const { status } =
                    await ImagePicker.requestCameraPermissionsAsync();
                  if (status !== "granted") {
                    Alert.alert(
                      "Permission needed",
                      "Please grant camera permissions."
                    );
                    return;
                  }
                  await handleImageSelection(ImagePicker.launchCameraAsync);
                }}
              >
                <View className="items-center">
                  <FontAwesome name="camera" size={24} color="black" />
                  <Text className="mt-2 text-lg font-bold">From Camera</Text>
                  <Text className="text-sm text-gray-700">
                    Straight from Camera
                  </Text>
                </View>
              </TouchableOpacity>
              <TouchableOpacity
                className="bg-[#f9be25] p-4 rounded-xl w-[48%]"
                onPress={async () => {
                  const { status } =
                    await ImagePicker.requestMediaLibraryPermissionsAsync();
                  if (status !== "granted") {
                    Alert.alert(
                      "Permission needed",
                      "Please grant gallery permissions."
                    );
                    return;
                  }
                  await handleImageSelection(
                    ImagePicker.launchImageLibraryAsync
                  );
                }}
              >
                <View className="items-center">
                  <Feather name="image" size={24} color="black" />
                  <Text className="mt-2 text-lg font-bold">From Gallery</Text>
                  <Text className="text-sm text-gray-700">
                    Straight from Gallery
                  </Text>
                </View>
              </TouchableOpacity>
            </View>
          </View>

          {/* Highlights section */}
          <View className="mb-8">
            <View className="flex-row items-center mb-4">
              <Text className="mr-2 text-2xl font-bold">Highlights</Text>
              <Ionicons name="star-outline" size={20} color="#bb0718" />
            </View>
            {isLoadingFoods ? (
              <Text className="text-center text-gray-500">
                Loading highlights...
              </Text>
            ) : foodsError ? (
              <Text className="text-center text-red-600">
                Failed to load highlights
              </Text>
            ) : filteredFoods.length === 0 ? (
              <Text className="text-center text-gray-400">
                No highlights available
              </Text>
            ) : (
              <View className="flex-row justify-between">
                {filteredFoods.map((food, idx) => (
                  <TouchableOpacity
                    key={food.id}
                    className="flex-1 mr-4 bg-white shadow-sm rounded-xl"
                    style={{
                      marginRight: idx === filteredFoods.length - 1 ? 0 : 12,
                    }}
                    onPress={() => navigateToFoodDetail(food.id)}
                  >
                    {food.image_url ? (
                      <Image
                        source={{ uri: food.image_url }}
                        className="w-full h-32 rounded-t-xl"
                        resizeMode="cover"
                      />
                    ) : (
                      <View className="items-center justify-center w-full h-32 bg-gray-200 rounded-t-xl">
                        <Text className="text-gray-400">No Image</Text>
                      </View>
                    )}
                    <View className="justify-between flex-1 p-3">
                      <Text
                        className="text-base font-bold text-[#333] mb-1"
                        numberOfLines={1}
                      >
                        {food.name}
                      </Text>
                      <Text
                        className="text-sm text-[#666] mb-2"
                        numberOfLines={1}
                      >
                        {food.description || "No description"}
                      </Text>
                      <View className="flex-row justify-between">
                        <View className="flex-row items-center">
                          <IconSymbol name="clock" size={12} color="#666" />
                          <Text className="text-xs text-[#666] ml-1">
                            {food.time_to_cook_minutes
                              ? `${food.time_to_cook_minutes} min`
                              : "-"}
                          </Text>
                        </View>
                      </View>
                    </View>
                  </TouchableOpacity>
                ))}
              </View>
            )}
          </View>
        </View>

        {/* Extra space at bottom */}
        <View className="h-20"></View>
      </ScrollView>
    </SafeAreaView>
  );
}
