import { useEffect, useState } from "react";
import { api } from "../api/client";
import type { ActivityListItem } from "../types/api";

function formatPace(avgSpeedMps: number | null): string | null {
  if (avgSpeedMps == null || avgSpeedMps <= 0) return null;
  const secPerKm = 1000 / avgSpeedMps;
  const m = Math.floor(secPerKm / 60);
  const s = Math.round(secPerKm % 60);
  return `${m}:${s.toString().padStart(2, "0")}/km`;
}

function lockReason(item: ActivityListItem): string {
  if (item.assignment_source === "manual") return "Manually assigned -- kept as-is by reclassify";
  if (item.workout_kind_name === "Race") return "Race, from Garmin metadata -- kept as-is by reclassify";
  return "";
}

export function Activities() {
  const [items, setItems] = useState<ActivityListItem[]>([]);
  const [error, setError] = useState<string | null>(null);

  useEffect(() => {
    api.listActivities().then(setItems).catch((e) => setError(String(e)));
  }, []);

  return (
    <div className="page">
      <h2>Activities</h2>
      {error && <p className="error">{error}</p>}

      {items.length === 0 ? (
        <p className="empty-state">No activities synced yet.</p>
      ) : (
        <table className="kinds-table">
          <thead>
            <tr>
              <th>Date</th>
              <th>Name</th>
              <th>Distance</th>
              <th>Pace</th>
              <th>Kind</th>
              <th>Source</th>
              <th></th>
            </tr>
          </thead>
          <tbody>
            {items.map((item) => {
              const pace = formatPace(item.AvgSpeedMps);
              return (
                <tr key={item.ID}>
                  <td>{item.StartTimeUTC}</td>
                  <td>{item.ActivityName || item.ActivityType}</td>
                  <td>{(item.DistanceMeters / 1000).toFixed(2)} km</td>
                  <td>{pace ?? "—"}</td>
                  <td>{item.workout_kind_name ?? "—"}</td>
                  <td>{item.assignment_source ?? "—"}</td>
                  <td>
                    {item.locked && (
                      <span className="lock-badge" title={lockReason(item)}>
                        Locked
                      </span>
                    )}
                  </td>
                </tr>
              );
            })}
          </tbody>
        </table>
      )}
    </div>
  );
}