import { useCallback, useRef, useState } from "react";
import { observer } from "mobx-react";
// icons
import { ListFilter, Search, X } from "lucide-react";
// types
import { TCycleFilters } from "@plane/types";
// components
import { CycleFiltersSelection } from "@/components/cycles";
import { FiltersDropdown } from "@/components/issues";
// helpers
import { cn } from "@/helpers/common.helper";
import { calculateTotalFilters } from "@/helpers/filter.helper";
// hooks
import { useCycleFilter } from "@/hooks/store";
import useOutsideClickDetector from "@/hooks/use-outside-click-detector";

type Props = {
  projectId: string;
};

export const CyclesViewHeader: React.FC<Props> = observer((props) => {
  const { projectId } = props;
  // refs
  const inputRef = useRef<HTMLInputElement>(null);
  // hooks
  const { currentProjectFilters, searchQuery, updateFilters, updateSearchQuery } = useCycleFilter();
  // states
  const [isSearchOpen, setIsSearchOpen] = useState(searchQuery !== "" ? true : false);
  // outside click detector hook
  useOutsideClickDetector(inputRef, () => {
    if (isSearchOpen && searchQuery.trim() === "") setIsSearchOpen(false);
  });

  const handleFilters = useCallback(
    (key: keyof TCycleFilters, value: string | string[]) => {
      if (!projectId) return;
      const newValues = currentProjectFilters?.[key] ?? [];

      if (Array.isArray(value))
        value.forEach((val) => {
          if (!newValues.includes(val)) newValues.push(val);
          else newValues.splice(newValues.indexOf(val), 1);
        });
      else {
        if (currentProjectFilters?.[key]?.includes(value)) newValues.splice(newValues.indexOf(value), 1);
        else newValues.push(value);
      }

      updateFilters(projectId, { [key]: newValues });
    },
    [currentProjectFilters, projectId, updateFilters]
  );

  const handleInputKeyDown = (e: React.KeyboardEvent<HTMLInputElement>) => {
    if (e.key === "Escape") {
      if (searchQuery && searchQuery.trim() !== "") updateSearchQuery("");
      else {
        setIsSearchOpen(false);
        inputRef.current?.blur();
      }
    }
  };

  const isFiltersApplied = calculateTotalFilters(currentProjectFilters ?? {}) !== 0;

  return (
    <div className="flex items-center gap-3">
      {!isSearchOpen && (
        <button
          type="button"
          className="-mr-5 p-2 hover:bg-custom-background-80 rounded text-custom-text-400 grid place-items-center"
          onClick={() => {
            setIsSearchOpen(true);
            inputRef.current?.focus();
          }}
        >
          <Search className="h-3.5 w-3.5" />
        </button>
      )}
      <div
        className={cn(
          "ml-auto flex items-center justify-start gap-1 rounded-md border border-transparent bg-custom-background-100 text-custom-text-400 w-0 transition-[width] ease-linear overflow-hidden opacity-0",
          {
            "w-64 px-2.5 py-1.5 border-custom-border-200 opacity-100": isSearchOpen,
          }
        )}
      >
        <Search className="h-3.5 w-3.5" />
        <input
          ref={inputRef}
          className="w-full max-w-[234px] border-none bg-transparent text-sm text-custom-text-100 placeholder:text-custom-text-400 focus:outline-none"
          placeholder="Search"
          value={searchQuery}
          onChange={(e) => updateSearchQuery(e.target.value)}
          onKeyDown={handleInputKeyDown}
        />
        {isSearchOpen && (
          <button
            type="button"
            className="grid place-items-center"
            onClick={() => {
              updateSearchQuery("");
              setIsSearchOpen(false);
            }}
          >
            <X className="h-3 w-3" />
          </button>
        )}
      </div>
      <FiltersDropdown
        icon={<ListFilter className="h-3 w-3" />}
        title="Filters"
        placement="bottom-end"
        isFiltersApplied={isFiltersApplied}
      >
        <CycleFiltersSelection filters={currentProjectFilters ?? {}} handleFiltersUpdate={handleFilters} />
      </FiltersDropdown>
    </div>
  );
});