'use client';

import { useState, useCallback, useMemo } from 'react';
import { useAppStore } from '@/components/state-provider';
import { useSessionGitStatus } from '@/hooks/domains/session/use-session-git-status';
import { useSessionCommits } from '@/hooks/domains/session/use-session-commits';
import { getPlanLastSeen } from '@/lib/local-storage';
import { approveSessionAction } from '@/app/actions/workspaces';
import { getWebSocketClient } from '@/lib/ws/connection';
import type { OpenFileTab } from '@/lib/types/backend';
import type { MobileSessionPanel } from '@/lib/state/slices/ui/types';

export type SelectedDiff = {
  path: string;
  content?: string;
};

type UseSessionLayoutStateOptions = {
  sessionId?: string | null;
};

/**
 * Shared hook for session layout state used across mobile, tablet, and desktop layouts.
 * Consolidates common state and logic to avoid duplication.
 */
export function useSessionLayoutState(options: UseSessionLayoutStateOptions = {}) {
  const { sessionId = null } = options;

  // --- Core session state ---
  const activeTaskId = useAppStore((state) => state.tasks.activeTaskId);
  const activeSessionId = useAppStore((state) => state.tasks.activeSessionId);
  const effectiveSessionId = activeSessionId ?? sessionId ?? null;
  const sessionKey = effectiveSessionId ?? '';

  const activeSession = useAppStore((state) =>
    effectiveSessionId ? state.taskSessions.items[effectiveSessionId] ?? null : null
  );
  const setTaskSession = useAppStore((state) => state.setTaskSession);

  // --- Agent state ---
  const isAgentWorking = activeSession?.state === 'STARTING' || activeSession?.state === 'RUNNING';

  const isPassthroughMode = useMemo(() => {
    if (!activeSession?.agent_profile_snapshot) return false;
    // eslint-disable-next-line @typescript-eslint/no-explicit-any
    const snapshot = activeSession.agent_profile_snapshot as any;
    return snapshot?.cli_passthrough === true;
  }, [activeSession?.agent_profile_snapshot]);

  // --- Diff selection state ---
  const [selectedDiff, setSelectedDiff] = useState<SelectedDiff | null>(null);

  const handleSelectDiff = useCallback((path: string, content?: string) => {
    setSelectedDiff({ path, content });
  }, []);

  const handleClearSelectedDiff = useCallback(() => {
    setSelectedDiff(null);
  }, []);

  // --- Open file request state ---
  const [openFileRequest, setOpenFileRequest] = useState<OpenFileTab | null>(null);

  const handleOpenFile = useCallback((file: OpenFileTab) => {
    setOpenFileRequest(file);
  }, []);

  const handleFileOpenHandled = useCallback(() => {
    setOpenFileRequest(null);
  }, []);

  // --- Git status for badges ---
  const gitStatus = useSessionGitStatus(effectiveSessionId);
  const { commits } = useSessionCommits(effectiveSessionId);

  const uncommittedCount = useMemo(() => {
    if (!gitStatus?.files) return 0;
    return Object.keys(gitStatus.files).length;
  }, [gitStatus]);

  const totalChangesCount = uncommittedCount + commits.length;

  // --- Mobile session state (computed before plan badge to use in badge logic) ---
  const activePanelBySessionId = useAppStore((state) => state.mobileSession.activePanelBySessionId);
  const isTaskSwitcherOpen = useAppStore((state) => state.mobileSession.isTaskSwitcherOpen);
  const setMobileSessionPanel = useAppStore((state) => state.setMobileSessionPanel);
  const setMobileSessionTaskSwitcherOpen = useAppStore((state) => state.setMobileSessionTaskSwitcherOpen);

  const currentMobilePanel: MobileSessionPanel = effectiveSessionId
    ? (activePanelBySessionId[effectiveSessionId] ?? 'chat')
    : 'chat';

  // --- Plan badge ---
  const plan = useAppStore((state) =>
    activeTaskId ? state.taskPlans.byTaskId[activeTaskId] : null
  );

  const hasUnseenPlanUpdate = useMemo(() => {
    // Don't show badge if we're viewing the plan
    if (!activeTaskId || !plan || currentMobilePanel === 'plan') return false;
    if (plan.created_by !== 'agent') return false;
    const lastSeen = getPlanLastSeen(activeTaskId);
    return plan.updated_at !== lastSeen;
  }, [activeTaskId, plan, currentMobilePanel]);

  // --- Approve button logic ---
  const showApproveButton =
    !!activeSession?.review_status &&
    activeSession.review_status !== 'approved' &&
    !isAgentWorking;

  const handleApprove = useCallback(async () => {
    if (!effectiveSessionId || !activeTaskId) return;
    try {
      const response = await approveSessionAction(effectiveSessionId);

      if (response?.session) {
        setTaskSession(response.session);
      }

      if (response?.workflow_step?.events?.on_enter?.some((a: { type: string }) => a.type === 'auto_start_agent')) {
        const client = getWebSocketClient();
        if (client) {
          client.send({
            type: 'request',
            action: 'orchestrator.start',
            payload: {
              task_id: activeTaskId,
              session_id: effectiveSessionId,
              workflow_step_id: response.workflow_step.id,
            },
          });
        }
      }
    } catch (error) {
      console.error('Failed to approve session:', error);
    }
  }, [effectiveSessionId, activeTaskId, setTaskSession]);

  const handlePanelChange = useCallback((panel: MobileSessionPanel) => {
    if (effectiveSessionId) {
      setMobileSessionPanel(effectiveSessionId, panel);
    }
  }, [effectiveSessionId, setMobileSessionPanel]);

  const handleMenuClick = useCallback(() => {
    setMobileSessionTaskSwitcherOpen(true);
  }, [setMobileSessionTaskSwitcherOpen]);

  return {
    // Core session
    activeTaskId,
    activeSessionId,
    effectiveSessionId,
    sessionKey,
    activeSession,

    // Agent state
    isAgentWorking,
    isPassthroughMode,

    // Diff selection
    selectedDiff,
    handleSelectDiff,
    handleClearSelectedDiff,

    // File open
    openFileRequest,
    handleOpenFile,
    handleFileOpenHandled,

    // Git status
    gitStatus,
    commits,
    uncommittedCount,
    totalChangesCount,

    // Plan
    plan,
    hasUnseenPlanUpdate,

    // Approve
    showApproveButton,
    handleApprove,

    // Mobile session panel
    currentMobilePanel,
    handlePanelChange,
    isTaskSwitcherOpen,
    handleMenuClick,
    setMobileSessionTaskSwitcherOpen,
  };
}