using ArkhamPnP.Data;
using iText.IO.Image;
using iText.Kernel.Pdf;
using iText.Layout;
using iText.Layout.Element;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Resources;
using System.Security.Cryptography.Xml;
using System.Text;
using System.Threading.Tasks;

namespace ArkhamPnP
{
	internal class PDFComposer
	{
		const float PAGE_WIDTH = 210; // mm
		const float PAGE_HEIGHT = 297; // mm
		const float CARD_WIDTH = 63; // mm
		const float CARD_HEIGHT = 89; // mm
		const float FRONT_PADDING = 3; // mm
		const float MARGIN_SIDE = 5; // mm
		const float MARGIN_TOP_BOTTOM = 5; // mm

		private ArkhamDBApi api;

		public PDFComposer()
		{
			api = new ArkhamDBApi();
		}

		public async Task PrintCards(List<Card> cards, string destinationPath)
		{
			var pdfDoc = new PdfDocument(new PdfWriter(destinationPath));
			var doc = new Document(pdfDoc, new iText.Kernel.Geom.PageSize(PAGE_WIDTH, PAGE_HEIGHT));
			// compute card amount on page
			int grid_width = 0;
			while (CARD_WIDTH * (grid_width + 1) + FRONT_PADDING * (grid_width + 1 - 1) +
				2 * MARGIN_SIDE <= PAGE_WIDTH) grid_width++;
			int grid_height = 0;
			while (CARD_HEIGHT * (grid_height + 1) + FRONT_PADDING * (grid_height + 1 - 1) +
				2 * MARGIN_TOP_BOTTOM <= PAGE_HEIGHT) grid_height++;
			Console.WriteLine("Will produce grid of cards " + grid_height + "x" + grid_width);
			// compute position of left-top card in page
			float left = (PAGE_WIDTH - grid_width * CARD_WIDTH - (grid_width - 1) * FRONT_PADDING) / 2;
			float top = (PAGE_HEIGHT - grid_height * CARD_HEIGHT - (grid_height - 1) * FRONT_PADDING) / 2;
			//
			ResourceManager rm = new ResourceManager("ArkhamPnP.Resources", Assembly.GetExecutingAssembly());
			byte[] playerBytes = rm.GetObject("player") as byte[];
			//
			int pos = 0;
			int current_page = 1;
			while (pos < cards.Count)
			{
				while (pdfDoc.GetNumberOfPages() < current_page + 1)
				{
					pdfDoc.AddNewPage(new iText.Kernel.Geom.PageSize(PAGE_WIDTH, PAGE_HEIGHT));
				}
				float front_left = left;
				float front_top = top;
				float rear_left = left - FRONT_PADDING / 2;
				float rear_top = top - FRONT_PADDING / 2;
				for (int i = 0; i < grid_height; i++)
				{
					for (int j = 0; j < grid_width; j++)
					{
						if (pos >= cards.Count) break;
						Console.WriteLine("Adding card " + (pos + 1) + " of " + cards.Count);
						var current_card = cards[pos];
						var front_image = await LoadImage(current_card);
						Image image = new Image(ImageDataFactory.Create(front_image)); 
						image.SetFixedPosition(current_page, front_left, front_top, CARD_WIDTH);
						pos++;
						doc.Add(image);
						front_left += CARD_WIDTH + FRONT_PADDING;
						// 
						Image backImage = new Image(ImageDataFactory.Create(playerBytes));
						backImage.SetFixedPosition(current_page + 1, PAGE_WIDTH - rear_left - (CARD_WIDTH + FRONT_PADDING), rear_top, CARD_WIDTH + FRONT_PADDING);
						doc.Add(backImage);
						rear_left += CARD_WIDTH + FRONT_PADDING;
					}
					front_left = left;
					front_top += CARD_HEIGHT + FRONT_PADDING;
					rear_left = left - FRONT_PADDING / 2;
					rear_top += CARD_HEIGHT + FRONT_PADDING;
					if (pos >= cards.Count) break;
				}
				current_page += 2;
			}
			doc.Close();
		}

		private async Task<string> LoadImage(Card card)
		{
			string assembly_folder = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
			var parts = card.image_src.Split('/');
			var destination_path = assembly_folder;
			for (int i = 0; i <  parts.Length; i++) destination_path = Path.Combine(destination_path, parts[i]);
			var directory = Path.GetDirectoryName(destination_path);
			if (!Directory.Exists(directory)) Directory.CreateDirectory(directory);
			if (File.Exists(destination_path)) return destination_path;
			var stream = await api.GetImage(card.image_src);
			var file_stream = File.Create(destination_path);
			await stream.CopyToAsync(file_stream);
			file_stream.Close();
			return destination_path;
		}
	}
}