import classNames from "classnames";
import type { FocusEvent, HTMLAttributes, ReactNode } from "react";
import {
  forwardRef,
  useCallback,
  useImperativeHandle,
  useLayoutEffect,
  useRef,
  useState,
} from "react";
import { useRandomKey } from "../../hooks/useRandomKey";
import { useStateWithDeps } from "../../hooks/useStateWithDeps";
import { generateId } from "../../lib/generateId";
import { IconButton } from "./IconButton";
import type { InputProps } from "./Input";
import { Label } from "./Label";
import { HStack } from "./Stacks";

export type PlainInputProps = Omit<
  InputProps,
  | "wrapLines"
  | "onKeyDown"
  | "type"
  | "stateKey"
  | "autocompleteVariables"
  | "autocompleteFunctions"
  | "autocomplete"
  | "extraExtensions"
  | "forcedEnvironmentId"
> &
  Pick<HTMLAttributes<HTMLInputElement>, "onKeyDownCapture"> & {
    onFocusRaw?: HTMLAttributes<HTMLInputElement>["onFocus"];
    type?: "text" | "password" | "number";
    step?: number;
    hideObscureToggle?: boolean;
    labelRightSlot?: ReactNode;
  };

export const PlainInput = forwardRef<{ focus: () => void }, PlainInputProps>(function PlainInput(
  {
    autoFocus,
    autoSelect,
    className,
    containerClassName,
    defaultValue,
    forceUpdateKey: forceUpdateKeyFromAbove,
    help,
    hideLabel,
    hideObscureToggle,
    label,
    labelClassName,
    labelPosition = "top",
    labelRightSlot,
    leftSlot,
    name,
    onBlur,
    onChange,
    onFocus,
    onFocusRaw,
    onKeyDownCapture,
    onPaste,
    placeholder,
    required,
    rightSlot,
    size = "md",
    tint,
    type = "text",
    validate,
  },
  ref,
) {
  // Track a local key for updates. If the default value is changed when the input is not in focus,
  // regenerate this to force the field to update.
  const [focusedUpdateKey, regenerateFocusedUpdateKey] = useRandomKey();
  const forceUpdateKey = `${forceUpdateKeyFromAbove}::${focusedUpdateKey}`;

  const [obscured, setObscured] = useStateWithDeps(type === "password", [type]);
  const [focused, setFocused] = useState(false);
  const [hasChanged, setHasChanged] = useStateWithDeps<boolean>(false, [forceUpdateKey]);
  const textareaRef = useRef<HTMLTextAreaElement>(null);
  const inputRef = useRef<HTMLInputElement>(null);

  useImperativeHandle<{ focus: () => void } | null, { focus: () => void } | null>(
    ref,
    () => inputRef.current,
  );

  const handleFocus = useCallback(
    (e: FocusEvent<HTMLInputElement>) => {
      onFocusRaw?.(e);
      setFocused(true);
      if (autoSelect) {
        inputRef.current?.select();
        textareaRef.current?.select();
      }
      onFocus?.();
    },
    [autoSelect, onFocus, onFocusRaw],
  );

  const handleBlur = useCallback(() => {
    setFocused(false);
    onBlur?.();
  }, [onBlur]);

  // Force input to update when receiving change and not in focus
  useLayoutEffect(() => {
    const isFocused = document.activeElement === inputRef.current;
    if (defaultValue != null && !isFocused) {
      regenerateFocusedUpdateKey();
    }
  }, [regenerateFocusedUpdateKey, defaultValue]);

  const id = useRef(`input-${generateId()}`);
  const commonClassName = classNames(
    className,
    "!bg-transparent min-w-0 w-full focus:outline-none placeholder:text-placeholder",
    "px-2 text-xs font-mono cursor-text",
  );

  const handleChange = useCallback(
    (value: string) => {
      onChange?.(value);
      setHasChanged(true);
      const isValid = (value: string) => {
        if (required && !validateRequire(value)) return false;
        if (typeof validate === "boolean") return validate;
        if (typeof validate === "function" && !validate(value)) return false;
        return true;
      };
      inputRef.current?.setCustomValidity(isValid(value) ? "" : "Invalid value");
    },
    [onChange, required, setHasChanged, validate],
  );

  const wrapperRef = useRef<HTMLDivElement>(null);

  return (
    <div
      ref={wrapperRef}
      className={classNames(
        "w-full",
        "pointer-events-auto", // Just in case we're placing in disabled parent
        labelPosition === "left" && "flex items-center gap-2",
        labelPosition === "top" && "flex-row gap-0.5",
      )}
    >
      <Label
        htmlFor={id.current}
        className={labelClassName}
        visuallyHidden={hideLabel}
        required={required}
        help={help}
        rightSlot={labelRightSlot}
      >
        {label}
      </Label>
      <HStack
        alignItems="stretch"
        className={classNames(
          containerClassName,
          "x-theme-input",
          "relative w-full rounded-md text",
          "border",
          "overflow-hidden",
          focused ? "border-border-focus" : "border-border-subtle",
          hasChanged && "has-[:invalid]:border-danger", // For built-in HTML validation
          size === "md" && "min-h-md",
          size === "sm" && "min-h-sm",
          size === "xs" && "min-h-xs",
          size === "2xs" && "min-h-2xs",
        )}
      >
        {tint != null && (
          <div
            aria-hidden
            className={classNames(
              "absolute inset-0 opacity-5 pointer-events-none",
              tint === "info" && "bg-info",
              tint === "warning" && "bg-warning",
            )}
          />
        )}
        {leftSlot}
        <HStack
          className={classNames(
            "w-full min-w-0",
            leftSlot ? "pl-0.5 -ml-2" : null,
            rightSlot ? "pr-0.5 -mr-2" : null,
          )}
        >
          <input
            id={id.current}
            ref={inputRef}
            key={forceUpdateKey}
            type={type === "password" && !obscured ? "text" : type}
            name={name}
            // oxlint-disable-next-line jsx-a11y/no-autofocus
            autoFocus={autoFocus}
            defaultValue={defaultValue ?? undefined}
            autoComplete="off"
            autoCapitalize="off"
            autoCorrect="off"
            onChange={(e) => handleChange(e.target.value)}
            onPaste={(e) => onPaste?.(e.clipboardData.getData("Text"))}
            className={classNames(commonClassName, "h-full")}
            onFocus={handleFocus}
            onBlur={handleBlur}
            required={required}
            placeholder={placeholder}
            onKeyDownCapture={onKeyDownCapture}
          />
        </HStack>
        {type === "password" && !hideObscureToggle && (
          <IconButton
            title={
              obscured
                ? `Show ${typeof label === "string" ? label : "field"}`
                : `Obscure ${typeof label === "string" ? label : "field"}`
            }
            size="xs"
            className="mr-0.5 group/obscure !h-auto my-0.5"
            iconClassName="group-hover/obscure:text"
            iconSize="sm"
            icon={obscured ? "eye" : "eye_closed"}
            onClick={() => setObscured((o) => !o)}
          />
        )}
        {rightSlot}
      </HStack>
    </div>
  );
});

function validateRequire(v: string) {
  return v.length > 0;
}