// "use client";

// import { useState, useEffect } from "react";
// import { useUploadContext } from "../_context/upload-context";
// // Sesuaikan import ini dengan lokasi service API Anda yang sebenarnya
// import uploadApi from "@/shared/services/map-upload"; 
// import { toast } from "sonner";

// // --- 1. Helper Load PDF.js via CDN (Sama seperti di use-upload.ts) ---
// const loadPdfJs = async () => {
//   return new Promise<any>((resolve, reject) => {
//     // Cek jika global variable sudah ada
//     if ((window as any).pdfjsLib) {
//       resolve((window as any).pdfjsLib);
//       return;
//     }

//     const script = document.createElement("script");
//     // Gunakan versi yang sama agar konsisten
//     script.src = "https://cdnjs.cloudflare.com/ajax/libs/pdf.js/3.11.174/pdf.min.js";
//     script.async = true;
    
//     script.onload = () => {
//       const pdfjsLib = (window as any).pdfjsLib;
//       // Set worker
//       pdfjsLib.GlobalWorkerOptions.workerSrc = 
//         "https://cdnjs.cloudflare.com/ajax/libs/pdf.js/3.11.174/pdf.worker.min.js";
//       resolve(pdfjsLib);
//     };

//     script.onerror = (err) => reject(err);
//     document.body.appendChild(script);
//   });
// };

// export function usePdfViewer() {
//   const { state, setState, goToStep } = useUploadContext();
//   const [pages, setPages] = useState<{ pageNum: number; imageUrl: string }[]>([]);
//   const [loading, setLoading] = useState(false);
//   const [localSelectedPages, setLocalSelectedPages] = useState<number[]>([]);

//   // Load PDF saat component mount atau file berubah
//   useEffect(() => {
//     if (state.file && state.step === "PDF_VIEWER") {
//       renderPdfPages(state.file);
//     }
//     // eslint-disable-next-line react-hooks/exhaustive-deps
//   }, [state.file, state.step]);

//   const renderPdfPages = async (pdfFile: File) => {
//     setLoading(true);
//     setPages([]); // Reset halaman lama

//     try {
//       // 1. Load Library dari CDN
//       const pdfjsLib = await loadPdfJs();

//       // 2. Baca File
//       const arrayBuffer = await pdfFile.arrayBuffer();
//       const pdf = await pdfjsLib.getDocument({ data: arrayBuffer }).promise;
//       const totalPages = pdf.numPages;
//       const pageImages = [];

//       // 3. Render Setiap Halaman ke Canvas -> Image URL
//       for (let pageNum = 1; pageNum <= totalPages; pageNum++) {
//         const page = await pdf.getPage(pageNum);
//         const viewport = page.getViewport({ scale: 1 }); // Scale 1 cukup untuk thumbnail
        
//         const canvas = document.createElement("canvas");
//         const ctx = canvas.getContext("2d");

//         if (ctx) {
//           canvas.height = viewport.height;
//           canvas.width = viewport.width;
          
//           await page.render({
//             canvasContext: ctx,
//             viewport: viewport,
//           }).promise;
          
//           pageImages.push({
//             pageNum,
//             imageUrl: canvas.toDataURL("image/jpeg", 0.8), // Gunakan JPEG kompresi agar ringan
//           });
//         }
//       }

//       setPages(pageImages);
//     } catch (err) {
//       console.error("PDF Error:", err);
//       toast.error("Gagal memuat halaman PDF. Pastikan file tidak korup.");
//     } finally {
//       setLoading(false);
//     }
//   };

//   const toggleSelectPage = (pageNum: number) => {
//     setLocalSelectedPages((prev) => {
//       if (prev.includes(pageNum)) {
//         return prev.filter((p) => p !== pageNum);
//       } else {
//         if (prev.length >= 20) {
//             toast.warning("Maksimal pilih 20 halaman.");
//             return prev; 
//         }
//         return [...prev, pageNum];
//       }
//     });
//   };

//   const handleProcessPdf = async () => {
//     if (localSelectedPages.length === 0) {
//         toast.warning("Pilih minimal 1 halaman.");
//         return;
//     }

//     setLoading(true);
//     try {
//       // Panggil API dengan halaman yang DIPILIH SAJA
//       const res = await uploadApi.uploadFile(
//         state.file!, 
//         localSelectedPages, 
//         null, 
//         state.fileDesc
//       );
      
//       setState(prev => ({ ...prev, result: res }));

//       // Routing Logic setelah upload PDF selesai
//       if (!res.tables) {
//         goToStep("VALIDATE"); 
//       } else if (res.tables.length > 1) {
//         goToStep("TABLE_PICKER"); 
//         toast.success("Beberapa tabel terdeteksi. Silakan pilih tabel.");
//       } else {
//         goToStep("TABLE_PICKER"); // Atau langsung validate tergantung kebutuhan
//       }
//     } catch (err: any) {
//       toast.error(err.message || "Gagal memproses halaman PDF");
//     } finally {
//       setLoading(false);
//     }
//   };

//   // 🔥 PENTING: Wajib me-return object ini agar tidak "undefined" di component
//   return {
//     pages,
//     loading,
//     localSelectedPages,
//     toggleSelectPage,
//     handleProcessPdf,
//   };
// }







"use client";

import { useState, useEffect } from "react";
import { useUploadContext } from "../_context/upload-context";
// Pastikan path ini sesuai dengan lokasi service API upload Anda
import uploadApi from "@/shared/services/map-upload"; 
import { toast } from "sonner";

// --- HELPER: Load PDF.js via CDN (Bypassing Webpack agar tidak Error) ---
const loadPdfJs = async () => {
  return new Promise<any>((resolve, reject) => {
    // 1. Cek jika library sudah ada di window
    if ((window as any).pdfjsLib) {
      resolve((window as any).pdfjsLib);
      return;
    }

    // 2. Inject Script jika belum ada
    const script = document.createElement("script");
    script.src = "https://cdnjs.cloudflare.com/ajax/libs/pdf.js/3.11.174/pdf.min.js";
    script.async = true;
    
    script.onload = () => {
      const pdfjsLib = (window as any).pdfjsLib;
      // Set worker source ke versi yang sama
      pdfjsLib.GlobalWorkerOptions.workerSrc = 
        "https://cdnjs.cloudflare.com/ajax/libs/pdf.js/3.11.174/pdf.worker.min.js";
      resolve(pdfjsLib);
    };

    script.onerror = (err) => reject(err);
    document.body.appendChild(script);
  });
};

export function usePdfViewer() {
  const { state, setState, goToStep } = useUploadContext();
  const [pages, setPages] = useState<{ pageNum: number; imageUrl: string }[]>([]);
  const [loading, setLoading] = useState(false);
  const [localSelectedPages, setLocalSelectedPages] = useState<number[]>([]);

  const MAX_SELECT = 20;

  // Efek untuk memuat halaman PDF saat komponen dipasang
  useEffect(() => {
    if (state.file && state.step === "PDF_VIEWER") {
      renderPdfPages(state.file);
    }
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [state.file, state.step]);

  // --- FUNGSI RENDER PDF KE GAMBAR ---
  const renderPdfPages = async (pdfFile: File) => {
    setLoading(true);
    setPages([]);
    try {
      const pdfjsLib = await loadPdfJs();
      const arrayBuffer = await pdfFile.arrayBuffer();
      const pdf = await pdfjsLib.getDocument({ data: arrayBuffer }).promise;
      const totalPages = pdf.numPages;
      const pageImages = [];

      for (let pageNum = 1; pageNum <= totalPages; pageNum++) {
        const page = await pdf.getPage(pageNum);
        const viewport = page.getViewport({ scale: 1 });
        const canvas = document.createElement("canvas");
        const ctx = canvas.getContext("2d");
        if (ctx) {
          canvas.height = viewport.height;
          canvas.width = viewport.width;
          await page.render({ canvasContext: ctx, viewport }).promise;
          pageImages.push({
            pageNum,
            imageUrl: canvas.toDataURL("image/jpeg", 0.7),
          });
        }
      }
      setPages(pageImages);
    } catch (err) {
      console.error("PDF Render Error:", err);
      toast.error("Gagal memuat visualisasi PDF.");
    } finally {
      setLoading(false);
    }
  };

  // --- FUNGSI PILIH HALAMAN ---
  const toggleSelectPage = (pageNum: number) => {
    setLocalSelectedPages((prev) => {
      if (prev.includes(pageNum)) {
        return prev.filter((p) => p !== pageNum);
      } else {
        if (prev.length >= MAX_SELECT) {
            toast.warning(`Maksimal ${MAX_SELECT} halaman yang dapat dipilih.`);
            return prev; 
        }
        return [...prev, pageNum];
      }
    });
  };

  // 🔥 SELECT ALL
  const isAllSelected = pages.length > 0 && localSelectedPages.length === Math.min(pages.length, MAX_SELECT);

  const handleSelectAll = () => {
    if (isAllSelected) {
      // Jika sudah terpilih semua (atau max), batalkan semua
      setLocalSelectedPages([]);
    } else {
      // Pilih semua (tapi batasi sesuai MAX_SELECT)
      const allPageNums = pages.map(p => p.pageNum).slice(0, MAX_SELECT);
      setLocalSelectedPages(allPageNums);
      
      if (pages.length > MAX_SELECT) {
          toast.info(`Otomatis memilih ${MAX_SELECT} halaman pertama (Batas Maksimum).`);
      }
    }
  };

  // --- LOGIKA PROSES UPLOAD & ROUTING YANG ANDA MINTA ---
  const handleProcessPdf = async () => {
    if (localSelectedPages.length === 0) {
        toast.warning("Harap pilih minimal 1 halaman untuk diproses.");
        return;
    }
    setLoading(true);
    try {
      const res = await uploadApi.uploadFile(
        state.file!, 
        localSelectedPages, 
        null, 
        state.fileDesc
      );
      setState(prev => ({ ...prev, result: res }));
      if (res.tables && res.tables.length > 0) {
        goToStep("TABLE_PICKER"); 
        toast.success(`Ditemukan ${res.tables.length} tabel. Silakan pilih tabel.`);
      } else {
        goToStep("VALIDATE"); 
        toast.info("Tabel tidak terdeteksi spesifik, lanjut ke validasi.");
      }
    } catch (err: any) {
      console.error(err);
      toast.error(err.message || "Gagal memproses halaman PDF terpilih.");
    } finally {
      setLoading(false);
    }
  };

  // 🔥 Return wajib agar tidak error destructuring undefined
  return {
    pages,
    loading,
    localSelectedPages,
    toggleSelectPage,
    handleProcessPdf,
    handleSelectAll,
    isAllSelected,
    MAX_SELECT
  };
}