var fs = require('fs');
var path = require('path');

// parameters
var inputFolder = "notes";
var outputFolder = "result";
var includeheaders = true;

var files = fs.readdirSync(inputFolder);

for (var i in files)
{
	var file = files[i];
	if (file.indexOf(".uecd") === -1)
	{
		fs.copyFileSync(path.join(inputFolder, file), path.join(outputFolder, file));
	}
	else
	{

		var data = fs.readFileSync(path.join(inputFolder, file), 'utf8');
		var md = mdify(JSON.parse(data), file);
		fs.writeFileSync(path.join(outputFolder, file).replace(".uecd", ".md"), md);
	}
}

function mdify(data, file)
{
	var result = "";
	var tags = [];

	for (var i in data.ops)
	{
		var op = data.ops[i];

		if (op.insert.image)
		{
			// inline base64
			//result += "![](" + op.insert.image + ")";

			//external
			var alt = op.attributes && op.attributes.alt ? op.attributes.alt : "";
			if (op.insert.image.indexOf("data:image") !== -1)
			{
				var buffer = Buffer.from(op.insert.image.replace(/^data:image\/jpeg;base64,/, ""), "base64");
				var imageFileName = file.replace(".uecd", i + ".jpeg");
				fs.writeFileSync(path.join(outputFolder, imageFileName), buffer);
				result += "![" + alt + "](" + imageFileName + ")";
			}
			else
			{
				result += "![" + alt + "](" + op.insert.image + ")";
			}
		}
		else if (!op.attributes)
		{
			if (op.insert.divider)
			{
				result += "---\n";
			}
			else
			{
				result += op.insert;
			}
		}
		else if (op.attributes.italic)
		{
			result += "*" + op.insert + "*";
		}
		else if (op.attributes.bold)
		{
			result += "**" + op.insert + "**";
		}
		else if (op.attributes.underline)
		{
			result += "__" + op.insert + "__";
		}
		else if (op.attributes.strike)
		{
			result += "~~" + op.insert + "~~";
		}
		else if (op.attributes.tag)
		{
			//result += "#" + op.insert;
			tags.push(op.insert);
		}
		else if (op.attributes.header)
		{
			var result = result.split("\n");
			result[result.length - 1] = "#".repeat(op.attributes.header) + " " + result[result.length - 1];
			result = result.join("\n");
			result += op.insert;
		}
		else if (op.attributes.link)
		{
			if (op.insert == op.attributes.link)
			{
				result += op.insert;
			}
			else
			{
				result += "[" + op.insert + "](" + op.attributes.link + ")";
			}
		}
		else if (op.attributes.code)
		{
			result += "`" + op.insert + "`";
		}
		else if (op.attributes.list == "bullet")
		{
			var result = result.split("\n");
			result[result.length - 1] = "\t".repeat(op.attributes.indent) + "* " + result[result.length - 1];
			result = result.join("\n");
			result += op.insert;
		}
		else if (op.attributes.list == "unchecked")
		{
			var result = result.split("\n");
			result[result.length - 1] = "\t".repeat(op.attributes.indent) + "[ ] " + result[result.length - 1];
			result = result.join("\n");
			result += op.insert;
		}
		else if (op.attributes.list == "checked")
		{
			var result = result.split("\n");
			result[result.length - 1] = "\t".repeat(op.attributes.indent) + "[x] " + result[result.length - 1];
			result = result.join("\n");
			result += op.insert;
		}
		else if (op.attributes.list == "ordered")
		{
			var result = result.split("\n");
			result[result.length - 1] = "\t".repeat(op.attributes.indent) + "1. " + result[result.length - 1];
			result = result.join("\n");
			result += op.insert;
		}
		else if (op.attributes.file)
		{
		   result += "[[" + op.attributes.file.filetitle + "]]";

		   // traditional link
		   //result += "[" + op.attributes.file.filetitle + "](" + op.attributes.file.filetitle + ".md)";
		}
		else if (op.attributes["code-block"])
		{
			var result = result.split("\n");
			result[result.length - 1] = "```" + result[result.length - 1] + "```";
			result = result.join("\n");
			result += op.insert.replace(/\n\n/g, "\n``````\n");;
		}
		else if (op.attributes.blockquote)
		{
			var result = result.split("\n");
			result[result.length - 1] = "> " + result[result.length - 1];
			result = result.join("\n");
			result += op.insert.replace(/\n\n/g, "\n> \n");
		}
		else
		{
		  result += op.insert;
		}
	}

	// Post processing

	// remove nbsp, indent and trailing
	result = result.replace(/ /g, " ");
	result = result.replace(/\n[ ]*/g, "\n");
	result = result.replace(/[ ]*\n/g, "\n");

	// insert line endings
	result = result.split('\n');
	var blockMarkers = ["* ", "1. ", "> ", "```", "["];
	for (var i = 0; i < result.length; i++)
	{
		var inBlock = false;
		for (var j in blockMarkers)
		{
			var block = blockMarkers[j];
			if (result[i].replace(/\t/g, "").startsWith(block) && result[i + 1].replace(/\t/g, "").startsWith(block))
			{
				inBlock = true;
				break;
			}
		}
		if (!inBlock && Boolean(result[i + 1]))
		{
			result.splice(i + 1, 0, "");
			i++;
		}
	}
	result = result.join("\n");

	// merge code blocks
	result = result.replace(/```\n```/g, "\n");
	result = result.replace(/```/g, "\n```\n");

	// escape ~ in unix path
	result = result.replace(/~\//g, "\\~/");

	// headers
	if (includeheaders)
	{
		var headers =
		{
			title: file.replace(".uecd", ""),
			tags: tags.join(", ")
		};

		if (/[.|mars|mai|juin|août] 202\d /.test(file))
		{
			var index = file.indexOf("202");
			headers.title = headers.title.substring(index + 5);
			headers.date = file.substring(0, index + 4);
		}

		var headersmd = "---\n";
		for (var i in headers)
		{
			headersmd += i + ": " + headers[i] + "\n";
		}
		headersmd += "---";

		if (result[0] != "\n") headersmd += "\n";
		if (result[1] != "\n") headersmd += "\n";

		result = headersmd + result;
	}

	return result;
}