/**
 * @license
 * Copyright 2025 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

import { Box, Static } from 'ink';
import { HistoryItemDisplay } from './HistoryItemDisplay.js';
import { ShowMoreLines } from './ShowMoreLines.js';
import { Notifications } from './Notifications.js';
import { OverflowProvider } from '../contexts/OverflowContext.js';
import { useUIState } from '../contexts/UIStateContext.js';
import { useAppContext } from '../contexts/AppContext.js';
import { AppHeader } from './AppHeader.js';
import { DebugModeNotification } from './DebugModeNotification.js';
import { useCompactMode } from '../contexts/CompactModeContext.js';

// Limit Gemini messages to a very high number of lines to mitigate performance
// issues in the worst case if we somehow get an enormous response from Gemini.
// This threshold is arbitrary but should be high enough to never impact normal
// usage.
const MAX_GEMINI_MESSAGE_LINES = 65536;

export const MainContent = () => {
  const { version } = useAppContext();
  const uiState = useUIState();
  const { frozenSnapshot } = useCompactMode();
  const {
    pendingHistoryItems,
    terminalWidth,
    mainAreaWidth,
    staticAreaMaxItemHeight,
    availableTerminalHeight,
  } = uiState;

  return (
    <>
      <Static
        key={`${uiState.historyRemountKey}-${uiState.currentModel}`}
        items={[
          <AppHeader key="app-header" version={version} />,
          <DebugModeNotification key="debug-notification" />,
          <Notifications key="notifications" />,
          ...uiState.history.map((h) => (
            <HistoryItemDisplay
              terminalWidth={terminalWidth}
              mainAreaWidth={mainAreaWidth}
              availableTerminalHeight={staticAreaMaxItemHeight}
              availableTerminalHeightGemini={MAX_GEMINI_MESSAGE_LINES}
              key={h.id}
              item={h}
              isPending={false}
              commands={uiState.slashCommands}
            />
          )),
        ]}
      >
        {(item) => item}
      </Static>
      <OverflowProvider>
        <Box flexDirection="column">
          {(frozenSnapshot ?? pendingHistoryItems).map((item, i) => {
            const isFrozen = frozenSnapshot !== null;
            return (
              <HistoryItemDisplay
                key={i}
                availableTerminalHeight={
                  uiState.constrainHeight ? availableTerminalHeight : undefined
                }
                terminalWidth={terminalWidth}
                mainAreaWidth={mainAreaWidth}
                item={{ ...item, id: 0 }}
                isPending={true}
                isFocused={isFrozen ? false : !uiState.isEditorDialogOpen}
                activeShellPtyId={isFrozen ? undefined : uiState.activePtyId}
                embeddedShellFocused={
                  isFrozen ? false : uiState.embeddedShellFocused
                }
              />
            );
          })}
          <ShowMoreLines constrainHeight={uiState.constrainHeight} />
        </Box>
      </OverflowProvider>
    </>
  );
};