import React, { useCallback, useMemo, useState, useEffect } from 'react';
import { Modal, Button, Text, ActionIcon } from '@mantine/core';
import { useMediaQuery } from '@mantine/hooks';
import { useAuth } from '@app/auth/UseSession';
import { isUserAnonymous } from '@app/auth/supabase';
import { useTranslation } from 'react-i18next';
import LocalIcon from '@app/components/shared/LocalIcon';
import Overview from '@app/components/shared/config/configSections/Overview';
import { createSaasConfigNavSections } from '@app/components/shared/config/saasConfigNavSections';
import { NavKey } from '@app/components/shared/config/types';
import { withBasePath } from '@app/constants/app';
import '@app/components/shared/AppConfigModal.css';
import { Z_INDEX_OVER_FULLSCREEN_SURFACE, Z_INDEX_OVER_SETTINGS_MODAL } from '@app/styles/zIndex';

interface AppConfigModalProps {
  opened: boolean;
  onClose: () => void;
}

const AppConfigModal: React.FC<AppConfigModalProps> = ({ opened, onClose }) => {
  const isMobile = useMediaQuery("(max-width: 1024px)");

  const { signOut, user, creditBalance, refreshCredits } = useAuth();
  const { t } = useTranslation();
  const [confirmOpen, setConfirmOpen] = useState(false);
  const [active, setActive] = useState<NavKey>('overview');
  const [notice, setNotice] = useState<string | null>(null);

  // Check if user can access billing features (non-anonymous users only)
  const isAnonymous = user ? isUserAnonymous(user) : false;
  useEffect(() => {
    const handler = (ev: Event) => {
      const detail = (ev as CustomEvent).detail as { key?: NavKey } | undefined;
      if (detail?.key) {
        setActive(detail.key);
      }
    };
    window.addEventListener('appConfig:navigate', handler as EventListener);
    return () => window.removeEventListener('appConfig:navigate', handler as EventListener);
  }, []);

  // Listen for notice updates (e.g., "Not enough credits..." next to Plan title)
  useEffect(() => {
    const handler = (ev: Event) => {
      const detail = (ev as CustomEvent).detail as { key?: NavKey; notice?: string } | undefined;
      if (detail?.notice && (detail?.key ? detail.key === 'plan' : true)) {
        setNotice(detail.notice);
      }
    };
    window.addEventListener('appConfig:notice', handler as EventListener);
    return () => window.removeEventListener('appConfig:notice', handler as EventListener);
  }, []);

  // When the modal opens to Plan, proactively refresh credits and log values
  useEffect(() => {
    if (!opened) return;
    if (active !== 'plan') return;
    console.log('[AppConfigModal] Opening Plan section. Current creditBalance:', creditBalance);
    (async () => {
      try {
        await refreshCredits();
      } catch (e) {
        console.warn('[AppConfigModal] Failed to refresh credits on Plan open:', e);
      }
    })();
  }, [opened, active]);

  useEffect(() => {
    if (!opened) return;
    if (active !== 'plan') return;
    console.log('[AppConfigModal] Credit balance updated while viewing Plan:', creditBalance);
  }, [opened, active, creditBalance]);

  const colors = useMemo(() => ({
    navBg: 'var(--modal-nav-bg)',
    sectionTitle: 'var(--modal-nav-section-title)',
    navItem: 'var(--modal-nav-item)',
    navItemActive: 'var(--modal-nav-item-active)',
    navItemActiveBg: 'var(--modal-nav-item-active-bg)',
    contentBg: 'var(--modal-content-bg)',
    headerBorder: 'var(--modal-header-border)',
  }), []);
  const isDev = process.env.NODE_ENV === 'development';

  const openLogoutConfirm = useCallback(() => setConfirmOpen(true), []);

  // Left navigation structure and icons
  const configNavSections = useMemo(
    () =>
      createSaasConfigNavSections(Overview, openLogoutConfirm, {
        isDev,
        isAnonymous,
        t,
      }),
    [openLogoutConfirm, isDev, isAnonymous, t],
  );

  const activeLabel = useMemo(() => {
    for (const section of configNavSections) {
      const found = section.items.find(i => i.key === active);
      if (found) return found.label;
    }
    return '';
  }, [configNavSections, active]);

  const activeComponent = useMemo(() => {
    for (const section of configNavSections) {
      const found = section.items.find(i => i.key === active);
      if (found) return found.component;
    }
    return null;
  }, [configNavSections, active]);

  return (
    <>
      <Modal
      opened={opened}
      onClose={onClose}
      title={null}
      size={isMobile ? "100%" : 980}
      centered
      radius="lg"
      withCloseButton={false}
      zIndex={Z_INDEX_OVER_FULLSCREEN_SURFACE}
      overlayProps={{ opacity: 0.35, blur: 2 }}
      padding={0}
      fullScreen={isMobile}
    >
      <div className="modal-container">
        {/* Left navigation */}
        <div
          className={`modal-nav ${isMobile ? 'mobile' : ''}`}
          style={{
            background: colors.navBg,
            borderRight: `1px solid ${colors.headerBorder}`,
          }}
        >
          <div className="modal-nav-scroll">
            {configNavSections.map(section => (
              <div key={section.title} className="modal-nav-section">
                {!isMobile && (
                  <Text size="xs" fw={600} c={colors.sectionTitle} style={{ textTransform: 'uppercase', letterSpacing: 0.4 }}>
                    {section.title}
                  </Text>
                )}
                <div className="modal-nav-section-items">
                  {section.items.map(item => {
                    const isActive = active === item.key;
                    const color = isActive ? colors.navItemActive : colors.navItem;
                    const iconSize = isMobile ? 28 : 18;
                    return (
                      <div
                        key={item.key}
                        onClick={() => setActive(item.key)}
                        className={`modal-nav-item ${isMobile ? 'mobile' : ''}`}
                        style={{
                          background: isActive ? colors.navItemActiveBg : 'transparent',
                        }}
                      >
                        <LocalIcon icon={item.icon} width={iconSize} height={iconSize} style={{ color }} />
                        {!isMobile && (
                          <Text size="sm" fw={500} style={{ color }}>
                            {item.label}
                          </Text>
                        )}
                      </div>
                    );
                  })}
                </div>
              </div>
            ))}
          </div>
        </div>

        {/* Right content */}
        <div className="modal-content">
          <div className="modal-content-scroll">
            {/* Sticky header with section title and small close button */}
            <div
              className="modal-header"
              style={{
                background: colors.contentBg,
                borderBottom: `1px solid ${colors.headerBorder}`,
              }}
            >
              <Text fw={700} size="lg">
                {activeLabel}
                {active === 'plan' && notice ? (
                  <span style={{ marginLeft: 8, fontWeight: 600, color: 'var(--mantine-color-yellow-7)' }}>
                    – {notice}
                  </span>
                ) : null}
              </Text>
              <ActionIcon variant="subtle" onClick={onClose} aria-label="Close">
                <LocalIcon icon="close-rounded" width={18} height={18} />
              </ActionIcon>
            </div>
            <div className="modal-body">
              {activeComponent}
            </div>
          </div>
        </div>
      </div>
      </Modal>
            {/* Confirm logout modal */}
      <Modal
        opened={confirmOpen}
        onClose={() => setConfirmOpen(false)}
        title="Sign out"
        centered
        zIndex={Z_INDEX_OVER_SETTINGS_MODAL}
      >
        <div className="confirm-modal-content">
          <Text>Are you sure you want to sign out?</Text>
          <div className="confirm-modal-buttons">
            <Button variant="default" onClick={() => setConfirmOpen(false)}>Cancel</Button>
            <Button
              color="red"
              onClick={async () => {
                try {
                  await signOut();
                } finally {
                  setConfirmOpen(false);
                  onClose();
                  window.location.href = withBasePath('/login');
                }
              }}
            >
              Sign out
            </Button>
          </div>
        </div>
      </Modal>
    </>
  );
};

export default AppConfigModal;