import { useState, FC, Fragment } from "react";

import { useRouter } from "next/router";

import useSWR from "swr";

// headless ui
import { Transition, Combobox } from "@headlessui/react";
// services
import projectServices from "services/project.service";
// ui
import { AssigneesList, Avatar } from "components/ui";
// icons
import { UserGroupIcon, MagnifyingGlassIcon, CheckIcon } from "@heroicons/react/24/outline";

// fetch keys
import { PROJECT_MEMBERS } from "constants/fetch-keys";

export type IssueAssigneeSelectProps = {
  projectId: string;
  value: string[];
  onChange: (value: string[]) => void;
};

export const IssueAssigneeSelect: FC<IssueAssigneeSelectProps> = ({
  projectId,
  value = [],
  onChange,
}) => {
  // states
  const [query, setQuery] = useState("");

  const router = useRouter();
  const { workspaceSlug } = router.query;

  // fetching project members
  const { data: people } = useSWR(
    workspaceSlug && projectId ? PROJECT_MEMBERS(projectId as string) : null,
    workspaceSlug && projectId
      ? () => projectServices.projectMembers(workspaceSlug as string, projectId as string)
      : null
  );

  const options = people?.map((person) => ({
    value: person.member.id,
    display:
      person.member.first_name && person.member.first_name !== ""
        ? person.member.first_name
        : person.member.email,
  }));

  const filteredOptions =
    query === ""
      ? options
      : options?.filter((option) => option.display.toLowerCase().includes(query.toLowerCase()));

  return (
    <Combobox
      as="div"
      value={value}
      onChange={(val) => onChange(val)}
      className="relative flex-shrink-0"
      multiple
    >
      {({ open }: any) => (
        <>
          <Combobox.Button
            className={({ open }) =>
              `flex cursor-pointer items-center rounded-md border text-xs shadow-sm duration-200 
              ${
                open
                  ? "border-theme bg-theme/5 outline-none ring-1 ring-theme "
                  : "hover:bg-theme/5 "
              }`
            }
          >
            {value && value.length > 0 && Array.isArray(value) ? (
              <span className="flex items-center justify-center gap-2 px-3 py-1">
                <AssigneesList userIds={value} length={3} showLength={false} />
                <span className=" text-gray-500">{value.length} Assignees</span>
              </span>
            ) : (
              <span className="flex items-center justify-center gap-2 px-3  py-1.5 text-xs">
                <UserGroupIcon className="h-4 w-4 text-gray-500 " />
                <span className=" text-gray-500">Assignee</span>
              </span>
            )}
          </Combobox.Button>

          <Transition
            show={open}
            as={Fragment}
            enter="transition ease-out duration-200"
            enterFrom="opacity-0 translate-y-1"
            enterTo="opacity-100 translate-y-0"
            leave="transition ease-in duration-150"
            leaveFrom="opacity-100 translate-y-0"
            leaveTo="opacity-0 translate-y-1"
          >
            <Combobox.Options
              className={`absolute z-10 mt-1 max-h-52 min-w-[8rem] overflow-auto rounded-md border-none
              bg-white px-2 py-2 text-xs shadow-md focus:outline-none`}
            >
              <div className="flex w-full items-center justify-start rounded-sm border-[0.6px] bg-gray-100 px-2">
                <MagnifyingGlassIcon className="h-3 w-3 text-gray-500" />
                <Combobox.Input
                  className="w-full  bg-transparent py-1 px-2 text-xs text-gray-500 focus:outline-none"
                  onChange={(event) => setQuery(event.target.value)}
                  placeholder="Search for a person..."
                  displayValue={(assigned: any) => assigned?.name}
                />
              </div>
              <div className="py-1.5">
                {filteredOptions ? (
                  filteredOptions.length > 0 ? (
                    filteredOptions.map((option) => (
                      <Combobox.Option
                        key={option.value}
                        className={({ active }) =>
                          `${
                            active ? "bg-hover-gray" : ""
                          } group flex min-w-[14rem] cursor-pointer select-none items-center gap-2 truncate rounded px-1 py-1.5 text-gray-500`
                        }
                        value={option.value}
                      >
                        {({ selected, active }) => (
                          <div className="flex w-full justify-between gap-2 rounded">
                            <div className="flex items-center justify-start gap-1">
                              <Avatar
                                user={people?.find((p) => p.member.id === option.value)?.member}
                              />
                              <span>{option.display}</span>
                            </div>
                            <div
                              className={`flex items-center justify-center rounded border border-gray-500  border-opacity-0 p-1 group-hover:border-opacity-100 
                              ${selected ? "border-opacity-100 " : ""}  
                              ${active ? "bg-gray-100" : ""} `}
                            >
                              <CheckIcon
                                className={`h-3 w-3 ${selected ? "opacity-100" : "opacity-0"}`}
                              />
                            </div>
                          </div>
                        )}
                      </Combobox.Option>
                    ))
                  ) : (
                    <p className="px-2 text-xs text-gray-500">No assignees found</p>
                  )
                ) : (
                  <p className="px-2 text-xs text-gray-500">Loading...</p>
                )}
              </div>
            </Combobox.Options>
          </Transition>
        </>
      )}
    </Combobox>
  );
};