module settings;

import std.stdio;
import ddhx;
import utils : unformat;
import core.stdc.stdlib : exit;
import std.format : format;

private enum
	ENOPARSE = "Could not parse number",
	ETRANGE = "Number %d out of range (1-%d)";

/**
 * Handles the Width setting from getopt.
 * Params:
 *   opt = Usually "w|width"
 *   val = Value to assign
 */
void HandleWCLI(string opt, string val) {
	HandleWidth(val, true);
}

/**
 * Handles the Width setting.
 * Params:
 *   val = Value to assign
 *   cli = From CLI (Assumes false by default)
 */
void HandleWidth(string val, bool cli = false) {
	switch (val[0]) {
	case 'a': // Automatic
		version (Windows) {
//TODO: Fix with CLI, returns 65535 (why can't Windows work?)
		if (!cli) BytesPerRow = getBytesPerRow;
		} else {
		BytesPerRow = getBytesPerRow;
		}
		break;

	case 'd': // Default
		BytesPerRow = 16;
		break;
	
	default:
		long l;
		if (unformat(val, l)) {
			if (l < 1 || l > ushort.max) {
				if (cli) {
					writefln(ETRANGE, l, ushort.max);
					exit(1);
				} else
					msgalt("Number out of range");
					return;
			}
			BytesPerRow = l & 0xFFFF;
		} else {
			if (cli) {
				writeln(ENOPARSE);
				exit(1);
			} else 
				msgalt(ENOPARSE);
		}
	}
}

/**
 * Handle offset CLI option.
 * Params:
 *   opt = Option
 *   val = Option value
 */
void HandleOCLI(string opt, string val) {
	HandleOffset(val, true);
}

/**
 * Handle offset setting.
 * Params:
 *   val = Value
 *   cli = From CLI?
 */
void HandleOffset(string val, bool cli = false) {
	switch (val[0]) {
	case 'o','O': CurrentOffsetType = OffsetType.Octal; break;
	case 'd','D': CurrentOffsetType = OffsetType.Decimal; break;
	case 'h','H': CurrentOffsetType = OffsetType.Hexadecimal; break;
	default:
		if (cli) {
			writef("Unknown mode parameter: %s", val);
			exit(1);
		} else {
			msgalt(format(" Invalid offset type: %s", val));
		}
		break;
	}
}

private ushort getBytesPerRow() {
	import ddcon : screenwidth;
	final switch (CurrentDisplayMode)
	{
		case DisplayMode.Default:
			return cast(ushort)((screenwidth - 11) / 4);
		case DisplayMode.Text, DisplayMode.Data:
			return cast(ushort)((screenwidth - 11) / 3);
	}
}