"use client";

import React, { useState, useEffect } from "react";
import { useForm, useField } from "@payloadcms/ui";
import { generateSlugAction } from "../../actions/generateField";
import { Button } from "@payloadcms/ui";

export function GenerateSlugButton({ path }: { path: string }) {
  const [isGenerating, setIsGenerating] = useState(false);
  const [instructions, setInstructions] = useState("");

  useEffect(() => {
    if (!isGenerating) return;
    const handleBeforeUnload = (e: BeforeUnloadEvent) => {
      e.preventDefault();
      e.returnValue =
        "Slug-Generierung läuft noch. Wenn Sie neu laden, bricht der Vorgang ab!";
    };
    window.addEventListener("beforeunload", handleBeforeUnload);
    return () => window.removeEventListener("beforeunload", handleBeforeUnload);
  }, [isGenerating]);

  const { fields, replaceState } = useForm();
  const { value, initialValue, setValue } = useField({ path });

  const extractText = (lexicalRoot: any): string => {
    if (!lexicalRoot) return "";
    let text = "";
    const iterate = (node: any) => {
      if (node.text) text += node.text + " ";
      if (node.children) node.children.forEach(iterate);
    };
    iterate(lexicalRoot);
    return text;
  };

  const handleGenerate = async () => {
    const title = (fields?.title?.value as string) || "";
    const lexicalValue = fields?.content?.value as any;
    const legacyValue = fields?.legacyMdx?.value as string;

    let draftContent = legacyValue || "";
    if (!draftContent && lexicalValue?.root) {
      draftContent = extractText(lexicalValue.root);
    }

    setIsGenerating(true);
    try {
      const res = await generateSlugAction(
        title,
        draftContent,
        initialValue as string,
        instructions,
      );
      if (res.success && res.slug) {
        setValue(res.slug);
      } else {
        alert("Fehler: " + res.error);
      }
    } catch (e) {
      console.error(e);
      alert("Unerwarteter Fehler.");
    } finally {
      setIsGenerating(false);
    }
  };

  return (
    <div className="flex gap-2 items-center mb-4">
      <textarea
        value={instructions}
        onChange={(e) => setInstructions(e.target.value)}
        placeholder="Optionale AI Anweisung für den Slug..."
        disabled={isGenerating}
        style={{
          width: "100%",
          minHeight: "40px",
          padding: "8px 12px",
          fontSize: "14px",
          borderRadius: "4px",
          border: "1px solid var(--theme-elevation-200)",
          background: "var(--theme-elevation-50)",
          color: "var(--theme-text)",
          marginBottom: "8px",
        }}
      />
      <button
        type="button"
        onClick={handleGenerate}
        disabled={isGenerating}
        className="btn btn--icon-style-none btn--size-medium ml-auto"
        style={{
          background: "var(--theme-elevation-150)",
          border: "1px solid var(--theme-elevation-200)",
          color: "var(--theme-text)",
          boxShadow: "0 2px 4px rgba(0,0,0,0.05)",
          transition: "all 0.2s ease",
          opacity: isGenerating ? 0.6 : 1,
          cursor: isGenerating ? "not-allowed" : "pointer",
        }}
      >
        <span className="btn__content">
          {isGenerating ? "✨ Generiere (ca 10s)..." : "✨ AI Slug Generieren"}
        </span>
      </button>
    </div>
  );
}