package launcher.serialize.config;

import java.io.IOException;
import java.io.Writer;
import java.util.List;
import java.util.Map;

import launcher.LauncherAPI;
import launcher.serialize.config.entry.BlockConfigEntry;
import launcher.serialize.config.entry.BooleanConfigEntry;
import launcher.serialize.config.entry.ConfigEntry;
import launcher.serialize.config.entry.IntegerConfigEntry;
import launcher.serialize.config.entry.ListConfigEntry;
import launcher.serialize.config.entry.StringConfigEntry;

public final class TextConfigWriter {
	private final Writer writer;
	private final boolean comments;

	private TextConfigWriter(Writer writer, boolean comments) {
		this.writer = writer;
		this.comments = comments;
	}

	private void writeBlock(BlockConfigEntry block, boolean brackets) throws IOException {
		// Write start bracket
		if (brackets) {
			writer.write('{');
		}

		// Write block entries
		Map<String, ConfigEntry<?>> map = block.getValue();
		for (Map.Entry<String, ConfigEntry<?>> mapEntry : map.entrySet()) {
			String name = mapEntry.getKey();
			ConfigEntry<?> entry = mapEntry.getValue();

			// Write entry name
			writeComment(entry.getComment(0));
			writer.write(name);
			writeComment(entry.getComment(1));
			writer.write(':');

			// Write entry value
			writeComment(entry.getComment(2));
			writeEntry(entry);
			writeComment(entry.getComment(3));
			writer.write(';');
		}
		writeComment(block.getComment(-1));

		// Write end bracket
		if (brackets) {
			writer.write('}');
		}
	}

	private void writeBoolean(BooleanConfigEntry entry) throws IOException {
		writer.write(entry.getValue().toString());
	}

	private void writeComment(String comment) throws IOException {
		if (comments && comment != null) {
			writer.write(comment);
		}
	}

	private void writeEntry(ConfigEntry<?> entry) throws IOException {
		ConfigEntry.Type type = entry.getType();
		switch (type) {
			case BLOCK:
				writeBlock((BlockConfigEntry) entry, true);
				break;
			case STRING:
				writeString((StringConfigEntry) entry);
				break;
			case INTEGER:
				writeInteger((IntegerConfigEntry) entry);
				break;
			case BOOLEAN:
				writeBoolean((BooleanConfigEntry) entry);
				break;
			case LIST:
				writeList((ListConfigEntry) entry);
				break;
			default:
				throw new AssertionError("Unsupported config entry type: " + type.name());
		}
	}

	private void writeInteger(IntegerConfigEntry entry) throws IOException {
		writer.write(Integer.toString(entry.getValue()));
	}

	private void writeList(ListConfigEntry entry) throws IOException {
		writer.write('[');

		// Write list elements
		List<ConfigEntry<?>> value = entry.getValue();
		for (int i = 0; i < value.size(); i++) {
			if (i > 0) {
				writer.write(',');
			}

			// Write element
			ConfigEntry<?> element = value.get(i);
			writeComment(element.getComment(0));
			writeEntry(element);
			writeComment(element.getComment(1));
		}
		writeComment(entry.getComment(-1));

		// Write end bracket
		writer.write(']');
	}

	private void writeString(StringConfigEntry entry) throws IOException {
		writer.write('"');

		// Quote string
		String s = entry.getValue();
		for (int i = 0; i < s.length(); i++) {
			char ch = s.charAt(i);
			switch (ch) {
				case '\t':
					writer.write("\\t");
					break;
				case '\b':
					writer.write("\\b");
					break;
				case '\n':
					writer.write("\\n");
					break;
				case '\r':
					writer.write("\\r");
					break;
				case '\f':
					writer.write("\\f");
					break;
				case '"':
				case '\\':
					writer.write('\\');
					writer.write(ch);
					break;
				default:
					writer.write(ch);
					break;
			}
		}

		// Write end quote
		writer.write('"');
	}

	@LauncherAPI
	public static void write(BlockConfigEntry block, Writer writer, boolean comments) throws IOException {
		new TextConfigWriter(writer, comments).writeBlock(block, false);
	}
}