notesnook/apps/mobile/app/components/header/index.js

import React, { useEffect, useState } from "react";
import { Platform, StyleSheet, View } from "react-native";
import { useSafeAreaInsets } from "react-native-safe-area-context";
import { SearchBar } from "../../screens/search/search-bar";
import {
  eSubscribeEvent,
  eUnSubscribeEvent
} from "../../services/event-manager";
import useNavigationStore from "../../stores/use-navigation-store";
import { useSelectionStore } from "../../stores/use-selection-store";
import { useThemeStore } from "../../stores/use-theme-store";
import { eScrollEvent } from "../../utils/events";
import { LeftMenus } from "./left-menus";
import { RightMenus } from "./right-menus";
import { Title } from "./title";

export const Header = React.memo(
  () => {
    const colors = useThemeStore((state) => state.colors);
    const insets = useSafeAreaInsets();
    const [hide, setHide] = useState(true);
    const selectionMode = useSelectionStore((state) => state.selectionMode);
    const currentScreen = useNavigationStore(
      (state) => state.currentScreen?.name
    );

    const onScroll = (data) => {
      if (data.y > 150) {
        if (!hide) return;
        setHide(false);
      } else {
        if (hide) return;
        setHide(true);
      }
    };

    useEffect(() => {
      eSubscribeEvent(eScrollEvent, onScroll);
      return () => {
        eUnSubscribeEvent(eScrollEvent, onScroll);
      };
    }, [hide]);

    return selectionMode ? null : (
      <>
        <View
          style={[
            styles.container,
            {
              marginTop: Platform.OS === "android" ? insets.top : null,
              backgroundColor: colors.bg,
              overflow: "hidden",
              borderBottomWidth: 1,
              borderBottomColor: hide ? "transparent" : colors.nav,
              justifyContent: "space-between"
            }
          ]}
        >
          {currentScreen === "Search" ? (
            <SearchBar />
          ) : (
            <>
              <View style={styles.leftBtnContainer}>
                <LeftMenus />
                <Title />
              </View>
              <RightMenus />
            </>
          )}
        </View>
      </>
    );
  },
  () => true
);

const styles = StyleSheet.create({
  container: {
    flexDirection: "row",
    zIndex: 11,
    height: 50,
    maxHeight: 50,
    justifyContent: "center",
    alignItems: "center",
    paddingHorizontal: 12,
    width: "100%"
  },
  leftBtnContainer: {
    flexDirection: "row",
    justifyContent: "flex-start",
    alignItems: "center",
    flexShrink: 1
  },
  leftBtn: {
    justifyContent: "center",
    alignItems: "center",
    height: 40,
    width: 40,
    borderRadius: 100,
    marginLeft: -5,
    marginRight: 25
  },
  rightBtnContainer: {
    flexDirection: "row",
    alignItems: "center"
  },
  rightBtn: {
    justifyContent: "center",
    alignItems: "flex-end",
    height: 40,
    width: 40,
    paddingRight: 0
  }
});