'use client';

import { useState, useEffect } from 'react';
import {
  Box,
  Paper,
  Typography,
  Button,
  IconButton,
  Collapse,
  FormControlLabel,
  Switch,
  Link,
  Slide,
} from '@mui/material';
import { Close, Settings as SettingsIcon, Cookie } from '@mui/icons-material';
import { useRouter } from 'next/navigation';

interface CookiePreferences {
  essential: boolean; // Always true, cannot be disabled
  analytics: boolean;
  marketing: boolean;
}

const COOKIE_CONSENT_KEY = 'parentflow_cookie_consent';
const COOKIE_PREFERENCES_KEY = 'parentflow_cookie_preferences';

export function CookieConsent() {
  const router = useRouter();
  const [showBanner, setShowBanner] = useState(false);
  const [showCustomize, setShowCustomize] = useState(false);
  const [preferences, setPreferences] = useState<CookiePreferences>({
    essential: true,
    analytics: false,
    marketing: false,
  });

  useEffect(() => {
    // Check if user has already given consent
    const consent = localStorage.getItem(COOKIE_CONSENT_KEY);
    if (!consent) {
      // Show banner after a short delay
      const timer = setTimeout(() => setShowBanner(true), 1000);
      return () => clearTimeout(timer);
    } else {
      // Load saved preferences
      const savedPrefs = localStorage.getItem(COOKIE_PREFERENCES_KEY);
      if (savedPrefs) {
        setPreferences(JSON.parse(savedPrefs));
      }
    }
  }, []);

  const savePreferences = (prefs: CookiePreferences) => {
    localStorage.setItem(COOKIE_CONSENT_KEY, 'true');
    localStorage.setItem(COOKIE_PREFERENCES_KEY, JSON.stringify(prefs));

    // Apply analytics based on user choice
    if (prefs.analytics) {
      console.log('📊 Analytics enabled');
      // TODO: Initialize analytics (Google Analytics, etc.)
    } else {
      console.log('📊 Analytics disabled');
      // TODO: Disable analytics
    }

    setShowBanner(false);
  };

  const handleAcceptAll = () => {
    const allPrefs: CookiePreferences = {
      essential: true,
      analytics: true,
      marketing: true,
    };
    setPreferences(allPrefs);
    savePreferences(allPrefs);
  };

  const handleRejectAll = () => {
    const essentialOnly: CookiePreferences = {
      essential: true,
      analytics: false,
      marketing: false,
    };
    setPreferences(essentialOnly);
    savePreferences(essentialOnly);
  };

  const handleSaveCustom = () => {
    savePreferences(preferences);
  };

  const handleToggleCustomize = () => {
    setShowCustomize(!showCustomize);
  };

  if (!showBanner) {
    return null;
  }

  return (
    <Slide direction="up" in={showBanner} mountOnEnter unmountOnExit>
      <Paper
        elevation={8}
        sx={{
          position: 'fixed',
          bottom: 0,
          left: 0,
          right: 0,
          zIndex: (theme) => theme.zIndex.snackbar,
          borderRadius: '16px 16px 0 0',
          maxWidth: { xs: '100%', md: 600 },
          mx: 'auto',
          mb: 0,
        }}
      >
        <Box sx={{ p: 3, position: 'relative' }}>
          {/* Close button */}
          <IconButton
            onClick={handleRejectAll}
            sx={{ position: 'absolute', top: 8, right: 8 }}
            size="small"
            aria-label="Reject all cookies"
          >
            <Close />
          </IconButton>

          {/* Cookie icon and title */}
          <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 2 }}>
            <Cookie sx={{ color: 'primary.main', fontSize: 28 }} />
            <Typography variant="h6" fontWeight="600">
              Cookie Preferences
            </Typography>
          </Box>

          {/* Description */}
          <Typography variant="body2" color="text.secondary" paragraph>
            We use cookies to enhance your experience, analyze site usage, and assist in our marketing efforts.
            Essential cookies are required for the app to function.{' '}
            <Link
              href="/legal/cookies"
              onClick={(e) => {
                e.preventDefault();
                router.push('/legal/cookies');
              }}
              sx={{ fontWeight: 'bold', textDecoration: 'underline', cursor: 'pointer' }}
            >
              Learn more
            </Link>
          </Typography>

          {/* Customize section */}
          <Collapse in={showCustomize}>
            <Box sx={{ my: 2, p: 2, bgcolor: 'background.default', borderRadius: 2 }}>
              <FormControlLabel
                control={
                  <Switch
                    checked={preferences.essential}
                    disabled
                    color="primary"
                  />
                }
                label={
                  <Box>
                    <Typography variant="body2" fontWeight="600">
                      Essential Cookies
                    </Typography>
                    <Typography variant="caption" color="text.secondary">
                      Required for the app to function. Cannot be disabled.
                    </Typography>
                  </Box>
                }
                sx={{ mb: 1, alignItems: 'flex-start' }}
              />

              <FormControlLabel
                control={
                  <Switch
                    checked={preferences.analytics}
                    onChange={(e) => setPreferences({ ...preferences, analytics: e.target.checked })}
                    color="primary"
                  />
                }
                label={
                  <Box>
                    <Typography variant="body2" fontWeight="600">
                      Analytics Cookies
                    </Typography>
                    <Typography variant="caption" color="text.secondary">
                      Help us understand how you use the app (anonymized data).
                    </Typography>
                  </Box>
                }
                sx={{ mb: 1, alignItems: 'flex-start' }}
              />

              <FormControlLabel
                control={
                  <Switch
                    checked={preferences.marketing}
                    onChange={(e) => setPreferences({ ...preferences, marketing: e.target.checked })}
                    color="primary"
                  />
                }
                label={
                  <Box>
                    <Typography variant="body2" fontWeight="600">
                      Marketing Cookies
                    </Typography>
                    <Typography variant="caption" color="text.secondary">
                      Used to deliver relevant content and track campaign performance.
                    </Typography>
                  </Box>
                }
                sx={{ alignItems: 'flex-start' }}
              />
            </Box>
          </Collapse>

          {/* Action buttons */}
          <Box
            sx={{
              display: 'flex',
              gap: 1,
              flexDirection: { xs: 'column', sm: 'row' },
              mt: 2,
            }}
          >
            {showCustomize ? (
              <>
                <Button
                  variant="outlined"
                  onClick={handleToggleCustomize}
                  fullWidth
                  sx={{ textTransform: 'none' }}
                >
                  Cancel
                </Button>
                <Button
                  variant="contained"
                  onClick={handleSaveCustom}
                  fullWidth
                  sx={{ textTransform: 'none' }}
                >
                  Save Preferences
                </Button>
              </>
            ) : (
              <>
                <Button
                  variant="outlined"
                  onClick={handleRejectAll}
                  fullWidth
                  sx={{ textTransform: 'none' }}
                >
                  Reject All
                </Button>
                <Button
                  variant="outlined"
                  startIcon={<SettingsIcon />}
                  onClick={handleToggleCustomize}
                  fullWidth
                  sx={{ textTransform: 'none' }}
                >
                  Customize
                </Button>
                <Button
                  variant="contained"
                  onClick={handleAcceptAll}
                  fullWidth
                  sx={{ textTransform: 'none' }}
                >
                  Accept All
                </Button>
              </>
            )}
          </Box>
        </Box>
      </Paper>
    </Slide>
  );
}