import React, { useState, useEffect } from 'react';
import axios from 'axios';
import styles from '../styles/Dashboard.module.css';
import { useNavigate } from 'react-router-dom';
import { FontAwesomeIcon } from '@fortawesome/react-fontawesome';
import { faTrash } from '@fortawesome/free-solid-svg-icons';
import Navbar from './Navbar';

function Dashboard() {
  document.title = 'LinkLogger | Dashboard';

  interface Log {
    id: number;
    link: string;
    timestamp: string;
    ip: string;
    location: string;
    browser: string;
    os: string;
    userAgent: string;
    isp: string;
  }

  interface Link {
    link: string;
    owner: number;
    redirect_link: string;
    expire_date: string;
  }

  const [links, setLinks] = useState<Link[]>([]);
  const [logs, setLogs] = useState<Log[]>([]);
  const [visibleLog, setVisibleLog] = useState<string | null>(null);
  const navigate = useNavigate();

  // Fetch links from API
  useEffect(() => {
    axios
      .get('/api/links')
      .then((res) => {
        if (res.status === 200) {
          setLinks(res.data);
        } else {
          navigate('/login');
        }
      })

      .catch((error: unknown) => {
        if (axios.isAxiosError(error)) {
          if (error.response?.status != 404) {
            navigate('/login');
          }
        }
      });
  }, []);

  // Fetch logs from API
  useEffect(() => {
    axios
      .get('/api/logs')
      .then((res) => {
        if (res.status === 200) {
          setLogs(res.data);
        } else {
          navigate('/login');
        }
      })
      .catch((error: unknown) => {
        if (axios.isAxiosError(error)) {
          if (error.response?.status != 404) {
            navigate('/login');
          }
        }
      });
  }, []);

  /**
   * Display or hide logs for a specific link
   * @param link The link to toggle logs for
   */
  const toggleLogRow = (link: string) => {
    setVisibleLog(visibleLog === link ? null : link);
  };

  /**
   * Delete a specific log
   * Gets the log ID from the SVG element's ID attribute
   * @param e The event object from the click
   * @returns void - updates state (setLogs) if successful
   */
  const deleteLog = (e: React.MouseEvent<SVGSVGElement>) => {
    const confirmDelete = confirm('Are you sure you want to delete this log?');
    if (!confirmDelete) return;

    const id = parseInt(e.currentTarget.id);
    axios
      .delete(`/api/logs/${id}`)
      .then((res) => {
        if (res.status === 200) {
          setLogs(logs.filter((log) => log.id !== id));
        }
      })
      .catch((error: unknown) => {
        if (axios.isAxiosError(error)) {
          // Return to login if we are unauthorized for some reason
          if (error.response?.status === 401) {
            navigate('/login');
          } else {
            alert('Failed to delete log. Please try again.');
          }
        }
      });
  };

  return (
    <>
      <Navbar />
      <table className={styles.mainTable}>
        <thead>
          <tr style={{ border: '2px solid #ccc' }}>
            <th>Link</th>
            <th>Visits</th>
            <th>Redirect</th>
            <th>Expire Date</th>
          </tr>
        </thead>
        <tbody>
          {/* If there are no links, put a special message */}
          {links.length === 0 && (
            <tr>
              <td colSpan={4}>
                <div className={styles.noLinks}>
                  You do not have any shortened links - try creating one.
                </div>
              </td>
            </tr>
          )}

          {/* For every link and its logs */}
          {links.map((link) => (
            <React.Fragment key={link.link}>
              <tr className={styles.linkTableRow}>
                <td>
                  <button
                    onClick={() => toggleLogRow(link.link)}
                    className={styles.linkButton}
                  >
                    {link.link}
                  </button>
                </td>
                <td>
                  {logs.filter((log) => log.link === link.link).length || 0}
                </td>
                <td>{link.redirect_link}</td>
                <td>{link.expire_date}</td>
              </tr>

              {/* Conditionally render logs for this link */}
              {visibleLog === link.link && (
                <tr className={styles.logTableRow}>
                  <td colSpan={6}>
                    <table>
                      <thead>
                        <tr>
                          <th>ID</th>
                          <th>Timestamp</th>
                          <th>IP</th>
                          <th>Location</th>
                          <th colSpan={2}>ISP</th>
                        </tr>
                      </thead>
                      <tbody>
                        {/* Render all logs for the link */}
                        {logs
                          .filter((log) => log.link === link.link)
                          .map((log, index, filteredLogs) => (
                            <tr key={log.id}>
                              <td>{filteredLogs.length - index}</td>
                              <td>{log.timestamp}</td>
                              <td>{log.ip}</td>
                              <td>{log.location}</td>
                              <td>{log.isp}</td>
                              <td>
                                <FontAwesomeIcon
                                  icon={faTrash}
                                  className={styles.trashBin}
                                  id={log.id.toString()}
                                  onClick={deleteLog}
                                />
                              </td>
                            </tr>
                          ))}
                        {/* If the link has no logs, put a special message */}
                        {logs.filter((log) => log.link === link.link).length ===
                          0 && (
                          <tr>
                            <td colSpan={6}>
                              <div className={styles.noLogs}>
                                No logs for this link
                              </div>
                            </td>
                          </tr>
                        )}
                      </tbody>
                    </table>
                  </td>
                </tr>
              )}
            </React.Fragment>
          ))}
        </tbody>
      </table>
    </>
  );
}

export default Dashboard;