import React from "react";
import { useMutation, useQuery } from "@tanstack/react-query";
import { listInvites, revokeInvite } from "../api/invites";
import { BandInviteListItem } from "../types/invite";

interface InviteManagementProps {
  bandId: string;
}

/**
 * Component for managing band invites
 * - List pending invites
 * - Revoke invites
 * - Show invite status
 */
export function InviteManagement({ bandId }: InviteManagementProps) {
  
  // Fetch invites
  const { data, isLoading, isError, error } = useQuery({
    queryKey: ["invites", bandId],
    queryFn: () => listInvites(bandId),
    retry: false,
  });

  // Revoke mutation
  const revokeMutation = useMutation({
    mutationFn: (inviteId: string) => revokeInvite(inviteId),
  });

  // Calculate pending invites
  const pendingInvites = data?.invites.filter(
    (invite) => !invite.is_used && invite.expires_at !== null
  ) || [];

  // Format expiry date
  const formatExpiry = (expiresAt: string | null | undefined) => {
    if (!expiresAt) return "No expiry";
    try {
      const date = new Date(expiresAt);
      const now = new Date();
      const diffHours = Math.floor((date.getTime() - now.getTime()) / (1000 * 60 * 60));
      
      if (diffHours <= 0) {
        return "Expired";
      } else if (diffHours < 24) {
        return `Expires in ${diffHours} hour${diffHours === 1 ? "" : "s"}`;
      } else {
        return `Expires in ${Math.floor(diffHours / 24)} days`;
      }
    } catch {
      return "Invalid date";
    }
  };



  /**
   * Copy invite token to clipboard
   */
  const copyToClipboard = (token: string) => {
    navigator.clipboard.writeText(window.location.origin + `/invite/${token}`);
    // Could add a toast notification here
  };

  if (isLoading) {
    return (
      <div style={styles.container}>
        <p>Loading invites...</p>
      </div>
    );
  }

  if (isError) {
    return (
      <div style={styles.container}>
        <p style={styles.error}>Error loading invites: {error.message}</p>
      </div>
    );
  }

  return (
    <div style={styles.container}>
      <div style={styles.header}>
        <h3 style={styles.title}>Pending Invites</h3>
        <span style={styles.count}>{pendingInvites.length} Pending</span>
      </div>

      {data && data.total === 0 ? (
        <p style={styles.empty}>No invites yet. Create one to share with others!</p>
      ) : (
        <>
          <div style={styles.list}>
            {data?.invites.map((invite: BandInviteListItem) => (
              <div key={invite.id} style={styles.inviteCard}>
                <div style={styles.inviteHeader}>
                  <span style={styles.inviteRole}>{invite.role}</span>
                  <span style={styles.inviteStatus}>
                    {invite.is_used ? "Used" : formatExpiry(invite.expires_at)}
                  </span>
                </div>
                
                <div style={styles.inviteDetails}>
                  <div style={styles.tokenContainer}>
                    <span style={styles.token} title={invite.token}>
                      {invite.token.substring(0, 8)}...{invite.token.substring(invite.token.length - 4)}
                    </span>
                    <button 
                      style={styles.copyButton}
                      onClick={() => copyToClipboard(invite.token)}
                    >
                      Copy Link
                    </button>
                  </div>
                </div>

                {!invite.is_used && invite.expires_at && new Date(invite.expires_at) > new Date() && (
                  <div style={styles.inviteActions}>
                    <button 
                      style={{...styles.button, background: "#dc2626", color: "white"}}
                      onClick={() => {
                        if (window.confirm("Are you sure you want to revoke this invite?")) {
                          revokeMutation.mutate(invite.id);
                        }
                      }}
                      disabled={revokeMutation.isPending}
                    >
                      {revokeMutation.isPending ? "Revoking..." : "Revoke"}
                    </button>
                  </div>
                )}
              </div>
            ))}
          </div>

          <div style={styles.stats}>
            <span style={styles.statItem}>
              Total invites: <span style={styles.highlight}>{data?.total}</span>
            </span>
            <span style={styles.statItem}>
              Pending: <span style={styles.highlight}>{pendingInvites.length}</span>
            </span>
          </div>
        </>
      )}
    </div>
  );
}

const styles: Record<string, React.CSSProperties> = {
  container: {
    background: "white",
    borderRadius: "8px",
    padding: "20px",
    marginBottom: "20px",
    boxShadow: "0 2px 4px rgba(0,0,0,0.1)",
  },
  header: {
    display: "flex",
    justifyContent: "space-between",
    alignItems: "center",
    marginBottom: "16px",
  },
  title: {
    fontSize: "16px",
    fontWeight: "bold" as const,
    margin: "0",
  },
  count: {
    color: "#6b7280",
    fontSize: "14px",
  },
  empty: {
    color: "#6b7280",
    textAlign: "center" as const,
    padding: "20px",
  },
  list: {
    display: "flex",
    flexDirection: "column" as const,
    gap: "12px",
  },
  inviteCard: {
    border: "1px solid #e5e7eb",
    borderRadius: "6px",
    padding: "16px",
    background: "white",
  },
  inviteHeader: {
    display: "flex",
    justifyContent: "space-between",
    alignItems: "center",
    marginBottom: "12px",
  },
  inviteRole: {
    padding: "4px 12px",
    borderRadius: "4px",
    fontSize: "12px",
    fontWeight: "500",
    background: "#f3f4f6",
    color: "#4b5563",
  },
  inviteStatus: {
    fontSize: "12px",
  },
  inviteDetails: {
    marginBottom: "12px",
  },
  tokenContainer: {
    display: "flex",
    gap: "8px",
    alignItems: "center",
    flexWrap: "wrap" as const,
  },
  token: {
    fontFamily: "monospace",
    fontSize: "12px",
    color: "#6b7280",
    whiteSpace: "nowrap" as const,
    overflow: "hidden",
    textOverflow: "ellipsis",
  },
  copyButton: {
    padding: "4px 12px",
    borderRadius: "4px",
    fontSize: "12px",
    background: "#3b82f6",
    color: "white",
    border: "none",
    cursor: "pointer",
  },
  inviteActions: {
    display: "flex",
    gap: "8px",
  },
  button: {
    padding: "8px 16px",
    borderRadius: "4px",
    fontSize: "12px",
    border: "none",
    cursor: "pointer",
    fontWeight: "500",
  },
  stats: {
    display: "flex",
    gap: "16px",
    fontSize: "14px",
  },
  statItem: {
    color: "#6b7280",
  },
  highlight: {
    color: "#ef4444",
    fontWeight: "bold" as const,
  },
  error: {
    color: "#dc2626",
  },
};