import { useState, useRef, useCallback, useEffect, useMemo, memo } from 'react';
import throttle from 'lodash/throttle';
import { useRecoilValue } from 'recoil';
import { getConfigDefaults } from 'librechat-data-provider';
import type { ImperativePanelHandle } from 'react-resizable-panels';
import { ResizableHandleAlt, ResizablePanel, ResizablePanelGroup } from '~/components/ui/Resizable';
import { useGetStartupConfig } from '~/data-provider';
import { normalizeLayout } from '~/utils';
import { useMediaQuery } from '~/hooks';
import SidePanel from './SidePanel';
import store from '~/store';

interface SidePanelProps {
  defaultLayout?: number[] | undefined;
  defaultCollapsed?: boolean;
  navCollapsedSize?: number;
  fullPanelCollapse?: boolean;
  artifacts?: React.ReactNode;
  children: React.ReactNode;
}

const defaultMinSize = 20;
const defaultInterface = getConfigDefaults().interface;

const SidePanelGroup = ({
  defaultLayout = [97, 3],
  defaultCollapsed = false,
  fullPanelCollapse = false,
  navCollapsedSize = 3,
  artifacts,
  children,
}: SidePanelProps) => {
  const { data: startupConfig } = useGetStartupConfig();
  const interfaceConfig = useMemo(
    () => startupConfig?.interface ?? defaultInterface,
    [startupConfig],
  );

  const panelRef = useRef<ImperativePanelHandle>(null);
  const [minSize, setMinSize] = useState(defaultMinSize);
  const [isCollapsed, setIsCollapsed] = useState(defaultCollapsed);
  const [fullCollapse, setFullCollapse] = useState(fullPanelCollapse);
  const [collapsedSize, setCollapsedSize] = useState(navCollapsedSize);

  const isSmallScreen = useMediaQuery('(max-width: 767px)');
  const hideSidePanel = useRecoilValue(store.hideSidePanel);

  const calculateLayout = useCallback(() => {
    if (artifacts == null) {
      const navSize = defaultLayout.length === 2 ? defaultLayout[1] : defaultLayout[2];
      return [100 - navSize, navSize];
    } else {
      const navSize = 0;
      const remainingSpace = 100 - navSize;
      const newMainSize = Math.floor(remainingSpace / 2);
      const artifactsSize = remainingSpace - newMainSize;
      return [newMainSize, artifactsSize, navSize];
    }
  }, [artifacts, defaultLayout]);

  const currentLayout = useMemo(() => normalizeLayout(calculateLayout()), [calculateLayout]);

  const throttledSaveLayout = useCallback(
    throttle((sizes: number[]) => {
      const normalizedSizes = normalizeLayout(sizes);
      localStorage.setItem('react-resizable-panels:layout', JSON.stringify(normalizedSizes));
    }, 350),
    [],
  );

  useEffect(() => {
    if (isSmallScreen) {
      setIsCollapsed(true);
      setCollapsedSize(0);
      setMinSize(defaultMinSize);
      setFullCollapse(true);
      localStorage.setItem('fullPanelCollapse', 'true');
      panelRef.current?.collapse();
      return;
    } else {
      setIsCollapsed(defaultCollapsed);
      setCollapsedSize(navCollapsedSize);
      setMinSize(defaultMinSize);
    }
  }, [isSmallScreen, defaultCollapsed, navCollapsedSize, fullPanelCollapse]);

  const minSizeMain = useMemo(() => (artifacts != null ? 15 : 30), [artifacts]);

  return (
    <>
      <ResizablePanelGroup
        direction="horizontal"
        onLayout={(sizes) => throttledSaveLayout(sizes)}
        className="transition-width relative h-full w-full flex-1 overflow-auto bg-presentation"
      >
        <ResizablePanel
          defaultSize={currentLayout[0]}
          minSize={minSizeMain}
          order={1}
          id="messages-view"
        >
          {children}
        </ResizablePanel>
        {artifacts != null && (
          <>
            <ResizableHandleAlt withHandle className="ml-3 bg-border-medium text-text-primary" />
            <ResizablePanel
              defaultSize={currentLayout[1]}
              minSize={minSizeMain}
              order={2}
              id="artifacts-panel"
            >
              {artifacts}
            </ResizablePanel>
          </>
        )}
        {!hideSidePanel && interfaceConfig.sidePanel === true && (
          <SidePanel
            panelRef={panelRef}
            minSize={minSize}
            setMinSize={setMinSize}
            isCollapsed={isCollapsed}
            setIsCollapsed={setIsCollapsed}
            collapsedSize={collapsedSize}
            setCollapsedSize={setCollapsedSize}
            fullCollapse={fullCollapse}
            setFullCollapse={setFullCollapse}
            defaultSize={currentLayout[currentLayout.length - 1]}
            hasArtifacts={artifacts != null}
            interfaceConfig={interfaceConfig}
          />
        )}
      </ResizablePanelGroup>
      <button
        aria-label="Close right side panel"
        className={`nav-mask ${!isCollapsed ? 'active' : ''}`}
        onClick={() => {
          setIsCollapsed(() => {
            localStorage.setItem('fullPanelCollapse', 'true');
            setFullCollapse(true);
            setCollapsedSize(0);
            setMinSize(0);
            return false;
          });
          panelRef.current?.collapse();
        }}
      />
    </>
  );
};

export default memo(SidePanelGroup);