import { useEffect, useState } from 'react';
import { Link } from 'react-router';
import { Spinner } from 'react-bootstrap';
import { signedGet, isSuccess } from '@/api/client';
import { asArray, rankRoleId, rankRoleName, rankRolePillLabel, userInitials } from '@/views/dashboard/helpers';
import EmptyChart from '@/views/dashboard/EmptyChart';

function podiumUsersFromRankRole(rankRole) {
  return asArray(rankRole?.users)
    .slice(0, 3)
    .map((row) => {
      const info = row.user || {};
      const name = String(info.name || '').trim();
      return {
        name,
        initials: userInitials(name),
        avatar: info.avatar || '',
        score: Number.isFinite(Number(row.score)) ? Number(row.score) : 0,
      };
    });
}

function Podium({ users }) {
  const slots = [users[1] || null, users[0] || null, users[2] || null];
  const ranks = [2, 1, 3];
  return (
    <div className="mlb-podium-row">
      {slots.map((user, index) => {
        const rank = ranks[index];
        return (
          <div key={rank} className={`mlb-col ${rank === 1 ? 'is-first' : ''} ${user ? '' : 'is-empty'}`}>
            {user ? (
              <>
                <div className="mlb-avatar-wrap">
                  {rank === 1 ? (
                    <span className="mlb-crown" aria-hidden="true">
                      <svg width="26" height="18" viewBox="0 0 26 18" fill="none">
                        <path d="M3 15.5L1 5l6.2 4L13 1l5.8 8L25 5l-2 10.5H3z" fill="#F0C94A" />
                        <path d="M4 15.5h18v2H4v-2z" fill="#E3B341" />
                      </svg>
                    </span>
                  ) : null}
                  <div className={`mlb-avatar rank-${rank}`}>
                    {user.avatar && !String(user.avatar).includes('ui-avatars.com') ? (
                      <img src={user.avatar} alt="" />
                    ) : (
                      user.initials
                    )}
                  </div>
                  <span className={`mlb-badge rank-${rank}`}>{rank}</span>
                </div>
                <div className="mlb-name" title={user.name}>
                  {user.name}
                </div>
                <div className={`mlb-bar rank-${rank}`}>{user.score}</div>
              </>
            ) : (
              <>
                <div className="mlb-name">-</div>
                <div className={`mlb-bar rank-${rank}`}>-</div>
              </>
            )}
          </div>
        );
      })}
    </div>
  );
}

function LeaderboardCard({ item }) {
  const [activeIndex, setActiveIndex] = useState(0);
  const pills = item.pills || [];
  const active = pills[activeIndex] || pills[0];
  const users = active?.podium_users || item.podium_users || [];
  const detailsUrl = active?.url || item.details_url || '#';

  return (
    <div className="col-6">
      <article className="mlb-card">
        <div className="mlb-card-head">
          <h3 className="mlb-card-title">{item.title}</h3>
          <div className="mlb-card-meta">
            <p className="mlb-card-date">
              <span>{item.interval_label || '—'}</span>
            </p>
            <Link className="mlb-card-details" to={detailsUrl}>
              View details
            </Link>
          </div>
        </div>
        <div className="mlb-podium">
          <Podium users={users} />
        </div>
        {pills.length ? (
          <div className="mlb-pills">
            {pills.map((pill, index) => (
              <button
                key={pill.label}
                type="button"
                className={`mlb-pill ${index === activeIndex ? 'is-active' : ''}`}
                onClick={() => setActiveIndex(index)}
              >
                {pill.label}
              </button>
            ))}
          </div>
        ) : null}
      </article>
    </div>
  );
}

export default function MilestoneTeamLeaderboard({ widget }) {
  const [items, setItems] = useState(null);

  useEffect(() => {
    const load = async () => {
      const response = await signedGet('reports', 'roles_leaderboard/list', {}, { timeout: 120000 });
      if (!isSuccess(response)) {
        setItems([]);
        return;
      }
      let leaderboards = response.data;
      if (leaderboards?.items) leaderboards = leaderboards.items;
      leaderboards = asArray(leaderboards);
      const mapped = leaderboards.map((board) => {
        const rankRoles = asArray(board.rank_roles);
        const pills = rankRoles.map((rankRole, index) => {
          const limit = Number(rankRole.limit) > 0 ? Number(rankRole.limit) : 10;
          const roleId = rankRoleId(rankRole);
          return {
            label: rankRolePillLabel(rankRole.title, limit, rankRoleName(rankRole)),
            url: `/leaderboard/dashboard?id=${encodeURIComponent(board.id || '')}&role=${encodeURIComponent(roleId)}`,
            podium_users: podiumUsersFromRankRole(rankRole),
            active: index === 0,
          };
        });
        const start = board.validity_start || '';
        const end = board.validity_end || '';
        return {
          id: board.id,
          title: board.name || widget.title || 'Leaderboard',
          interval_label: `${start}${start && end ? ' – ' : ''}${end}`.trim(),
          details_url: pills[0]?.url || `/leaderboard/dashboard?id=${encodeURIComponent(board.id || '')}`,
          podium_users: pills[0]?.podium_users || [],
          pills,
        };
      });
      setItems(mapped);
    };
    load();
  }, [widget.title]);

  return (
    <div className="mb-3">
      <div className="row">
        <div className="col-12">
          <div className="page-title-box">
            <h4 className="page-title">{widget.title || 'Leaderboard'}</h4>
          </div>
        </div>
      </div>
      {items === null ? (
        <div className="text-center py-4">
          <Spinner animation="border" />
          <p className="text-muted mt-2 mb-0">Loading leaderboards...</p>
        </div>
      ) : items.length === 0 ? (
        <EmptyChart type="radialBar" label="No data" />
      ) : (
        <div className="row">
          {items.map((item) => (
            <LeaderboardCard key={item.id} item={item} />
          ))}
        </div>
      )}
    </div>
  );
}