package com.lemenzo.gallery.privacy;

import android.content.ContentProvider;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.net.Uri;
import android.os.ParcelFileDescriptor;
import android.provider.OpenableColumns;

import java.io.File;
import java.io.FileNotFoundException;

/** Read-only provider for short-lived sanitized share copies in app cache. */
public final class PrivateShareProvider extends ContentProvider {
    public static final String AUTHORITY = "com.lemenzo.gallery.private-share";

    @Override public boolean onCreate() { return true; }

    private File resolve(Uri uri) throws FileNotFoundException {
        if (uri == null || uri.getPathSegments().size() != 1) throw new FileNotFoundException();
        String name = uri.getLastPathSegment();
        if (name == null || name.contains("/") || name.contains("..")) throw new FileNotFoundException();
        File root = new File(getContext().getCacheDir(), "private_share");
        File file = new File(root, name);
        try {
            if (!file.getCanonicalPath().startsWith(root.getCanonicalPath() + File.separator)) throw new FileNotFoundException();
        } catch (Exception e) { throw new FileNotFoundException(); }
        if (!file.isFile()) throw new FileNotFoundException();
        return file;
    }

    @Override public ParcelFileDescriptor openFile(Uri uri, String mode) throws FileNotFoundException {
        if (!"r".equals(mode)) throw new FileNotFoundException("Read only");
        return ParcelFileDescriptor.open(resolve(uri), ParcelFileDescriptor.MODE_READ_ONLY);
    }

    @Override public String getType(Uri uri) {
        String name = uri == null ? null : uri.getLastPathSegment();
        if (name == null) return "application/octet-stream";
        String lower = name.toLowerCase();
        if (lower.endsWith(".png")) return "image/png";
        if (lower.endsWith(".webp")) return "image/webp";
        return "image/jpeg";
    }

    @Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
        try {
            File file = resolve(uri);
            String[] columns = projection == null ? new String[] {OpenableColumns.DISPLAY_NAME, OpenableColumns.SIZE} : projection;
            MatrixCursor cursor = new MatrixCursor(columns, 1);
            MatrixCursor.RowBuilder row = cursor.newRow();
            for (String column : columns) {
                if (OpenableColumns.DISPLAY_NAME.equals(column)) row.add(file.getName());
                else if (OpenableColumns.SIZE.equals(column)) row.add(file.length());
                else row.add(null);
            }
            return cursor;
        } catch (FileNotFoundException e) { return null; }
    }

    @Override public int delete(Uri uri, String selection, String[] selectionArgs) { return 0; }
    @Override public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) { return 0; }
    @Override public Uri insert(Uri uri, ContentValues values) { return null; }
}