"use client";

import { type ReactNode, useEffect, useRef, useState } from "react";
import aiStyles from "@/styles/ai.module.css";
import styles from "./RichTextArea.module.css";

const FONT_SIZES = [
  { value: "2", label: "S" },
  { value: "3", label: "M" },
  { value: "4", label: "L" },
  { value: "5", label: "XL" },
] as const;

function escapeAttr(value: string) {
  return value
    .replace(/&/g, "&")
    .replace(/"/g, """)
    .replace(/</g, "&lt;");
}

export default function RichTextArea({
  label,
  value,
  onChange,
  disabled,
  minHeight = 200,
  toolbarEnd,
  aiWorking = false,
  onUploadImage,
}: {
  label: string;
  value: string;
  onChange: (html: string) => void;
  disabled?: boolean;
  minHeight?: number;
  toolbarEnd?: ReactNode;
  aiWorking?: boolean;
  onUploadImage?: (file: File) => Promise<string>;
}) {
  const ref = useRef<HTMLDivElement>(null);
  const imageInputRef = useRef<HTMLInputElement>(null);
  const [direction, setDirection] = useState<"ltr" | "rtl">("ltr");
  const [fontSize, setFontSize] = useState("3");
  const [uploadingImage, setUploadingImage] = useState(false);
  const [imageError, setImageError] = useState("");

  useEffect(() => {
    const node = ref.current;
    if (!node) return;
    if (node.innerHTML !== value) {
      node.innerHTML = value || "";
    }
  }, [value]);

  function emit() {
    onChange(ref.current?.innerHTML ?? "");
  }

  function exec(command: string, commandValue?: string) {
    if (disabled) return;
    ref.current?.focus();
    document.execCommand(command, false, commandValue);
    emit();
  }

  function applyFontSize(size: string) {
    setFontSize(size);
    exec("fontSize", size);
  }

  function applyDirection(next: "ltr" | "rtl") {
    setDirection(next);
    const node = ref.current;
    if (!node || disabled) return;
    node.setAttribute("dir", next);
    node.focus();
    emit();
  }

  async function insertImage(file: File) {
    if (!onUploadImage || disabled) return;
    setUploadingImage(true);
    setImageError("");
    try {
      const url = await onUploadImage(file);
      if (
        !url.startsWith("/") &&
        !url.startsWith("http://") &&
        !url.startsWith("https://")
      ) {
        throw new Error("Could not add image.");
      }
      ref.current?.focus();
      document.execCommand(
        "insertHTML",
        false,
        `<img src="${escapeAttr(url)}" alt="" />`,
      );
      emit();
    } catch (err) {
      setImageError(
        err instanceof Error ? err.message : "Could not add image.",
      );
    } finally {
      setUploadingImage(false);
    }
  }

  return (
    <div className={styles.wrap}>
      <div className={styles.head}>
        {label ? <span className={styles.label}>{label}</span> : null}
        <div className={styles.tools}>
          <button
            type="button"
            className={styles.tool}
            disabled={disabled}
            title="Bold"
            onClick={() => exec("bold")}
          >
            B
          </button>
          <button
            type="button"
            className={styles.tool}
            disabled={disabled}
            title="Italic"
            onClick={() => exec("italic")}
          >
            I
          </button>
          <button
            type="button"
            className={styles.tool}
            disabled={disabled}
            title="Bullet list"
            onClick={() => exec("insertUnorderedList")}
          >
            • List
          </button>
          {onUploadImage ? (
            <button
              type="button"
              className={styles.tool}
              disabled={disabled || uploadingImage}
              title="Insert image"
              onClick={() => imageInputRef.current?.click()}
            >
              {uploadingImage ? "…" : "Image"}
            </button>
          ) : null}

          <span className={styles.toolSep} aria-hidden />

          <label className={styles.toolSelectWrap}>
            <span className={styles.srOnly}>Font size</span>
            <select
              className={styles.toolSelect}
              value={fontSize}
              disabled={disabled}
              title="Font size"
              onChange={(event) => applyFontSize(event.target.value)}
            >
              {FONT_SIZES.map((size) => (
                <option key={size.value} value={size.value}>
                  Size {size.label}
                </option>
              ))}
            </select>
          </label>

          <span className={styles.toolSep} aria-hidden />

          <button
            type="button"
            className={`${styles.tool} ${direction === "ltr" ? styles.toolActive : ""}`}
            disabled={disabled}
            title="Left to right"
            onClick={() => applyDirection("ltr")}
          >
            LTR
          </button>
          <button
            type="button"
            className={`${styles.tool} ${direction === "rtl" ? styles.toolActive : ""}`}
            disabled={disabled}
            title="Right to left"
            onClick={() => applyDirection("rtl")}
          >
            RTL
          </button>

          <span className={styles.toolSep} aria-hidden />

          <button
            type="button"
            className={styles.tool}
            disabled={disabled}
            title="Align left"
            onClick={() => exec("justifyLeft")}
          >
            Left
          </button>
          <button
            type="button"
            className={styles.tool}
            disabled={disabled}
            title="Align center"
            onClick={() => exec("justifyCenter")}
          >
            Center
          </button>
          <button
            type="button"
            className={styles.tool}
            disabled={disabled}
            title="Align right"
            onClick={() => exec("justifyRight")}
          >
            Right
          </button>
          <button
            type="button"
            className={styles.tool}
            disabled={disabled}
            title="Justify"
            onClick={() => exec("justifyFull")}
          >
            Justify
          </button>

          {toolbarEnd ? (
            <div className={styles.toolEnd}>{toolbarEnd}</div>
          ) : null}
        </div>
      </div>
      {imageError ? <p className={styles.imageError}>{imageError}</p> : null}
      <div
        ref={ref}
        className={`${styles.editor}${aiWorking ? ` ${aiStyles.aiWorkingBorder}` : ""}`}
        style={{ minHeight }}
        contentEditable={!disabled}
        suppressContentEditableWarning
        dir={direction}
        onInput={emit}
        onBlur={emit}
      />
      {onUploadImage ? (
        <input
          ref={imageInputRef}
          type="file"
          accept="image/*"
          className={styles.fileInput}
          disabled={disabled || uploadingImage}
          onChange={(event) => {
            const file = event.target.files?.[0];
            event.target.value = "";
            if (file) void insertImage(file);
          }}
        />
      ) : null}
    </div>
  );
}