sources/format.h

/*
	Copyright 2014 Teemu Piippo
	All rights reserved.

	Redistribution and use in source and binary forms, with or without
	modification, are permitted provided that the following conditions
	are met:

	1. Redistributions of source code must retain the above copyright
	   notice, this list of conditions and the following disclaimer.
	2. Redistributions in binary form must reproduce the above copyright
	   notice, this list of conditions and the following disclaimer in the
	   documentation and/or other materials provided with the distribution.
	3. Neither the name of the copyright holder nor the names of its
	   contributors may be used to endorse or promote products derived from
	   this software without specific prior written permission.

	THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
	TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
	PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER
	OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
	EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
	PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
	LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
	NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
	SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#pragma once
#include "mystring.h"
#include "basics.h"
#include "geometry.h"

#define FORMAT_OVERLOAD(T) \
	inline FUNCTION make_format_argument (T a) -> String

//
// -------------------------------------------------------------------------------------------------
//

FORMAT_OVERLOAD (String) { return a; }
FORMAT_OVERLOAD (char) { return String (a); }
FORMAT_OVERLOAD (int) { return String::from_number (a); }
FORMAT_OVERLOAD (long int) { return String::from_number (a); }
FORMAT_OVERLOAD (double) { return String::from_number (a); }
FORMAT_OVERLOAD (size_t) { return String::from_number (a); }
FORMAT_OVERLOAD (const char*) { return a; }
FORMAT_OVERLOAD (std::nullptr_t) { (void) a; return "<null pointer>"; }
FORMAT_OVERLOAD (bool) { return a ? "true" : "false"; }

FORMAT_OVERLOAD (const void*)
{
	String result;
	result.sprintf ("%p", a);
	return result;
}

template<typename T>
FORMAT_OVERLOAD (const List<T>&)
{
	String result;

	if (a.is_empty())
		return "{}";

	result = "{";

	for (auto it = a.begin(); it != a.end(); ++it)
	{
		if (it != a.begin())
			result += ", ";

		result += make_format_argument (*it);
	}

	result += "}";
	return result;
}

FORMAT_OVERLOAD (Color)
{
	static const char* colorstrings[] =
	{
		"BLACK", "RED", "GREEN", "YELLOW",
		"BLUE", "MAGENTA", "CYAN", "WHITE", "DEFAULT"
	};

	static_assert (sizeof colorstrings / sizeof *colorstrings == NUM_COLORS,
		"colostrings[] has an incorrect amount of elements");

	if (int (a) >= 0 and int (a) < NUM_COLORS)
		return colorstrings[int (a)];

	return "???";
}

FORMAT_OVERLOAD (Position) { return String ("(") + a.x + ", " + a.y + ")"; }
FORMAT_OVERLOAD (Size) { return String ("(") + a.width + "x" + a.height + ")"; }

FORMAT_OVERLOAD (Rectangle)
{
	String result;
	result.sprintf ("{(%d, %d), (%dx%d)}", a.x, a.y, a.width, a.height);
	return result;
}

// -------------------------------------------------------------------------------------------------
// Formats the given string with the given args.
//
FUNCTION format_args (const String& fmtstr, const Vector<String>& args) -> String;

// -------------------------------------------------------------------------------------------------
// Expands the given arguments into a vector of strings.
//
template<typename T, typename... RestTypes> FUNCTION
expand_format_arguments (Vector<String>& data, const T& arg, const RestTypes& ... rest) -> void
{
	data.append (make_format_argument (arg));
	expand_format_arguments (data, rest...);
}

static void expand_format_arguments (Vector<String>&) __attribute__((unused));
static void expand_format_arguments (Vector<String>&) {}

// -------------------------------------------------------------------------------------------------
//
// Formats the given formatter string and args and returns the string.
// This is essentially a modernized sprintf.
//
// Args in the format string take the form %n where n is a digit. The argument
// will be expanded to the nth argument passed. This is essentially Qt's
// QString::arg() syntax. Note: %0 is invalid.
//
// Arguments can be passed a modifier which takes the form of a character
// just before the digit. Currently supported modifiers are s, d and x.
//
// - s: The argument will expand into "s" if it would've not expanded into "1"
//      otherwise. If it would have expanded into "1" it will expand into an
//      empty string.
//
// - d: The argument expands into the numeric form of the first character of
//      its previous expansion. Use this to get numeric forms of @c char
//      arguments.
//
// - x: The numeric argument will be represented in hexadecimal notation. This
//      will work if the argument is a string representing a number. If the
//      argument did not expand into a number in the first place, 0 is used
//      and 0x0 is printed.
//
template<typename... argtypes> FUNCTION
format (const String& fmtstr, const argtypes&... raw_args) -> String
{
	Vector<String> args;
	expand_format_arguments (args, raw_args...);
	return format_args (fmtstr, args);
}

// -------------------------------------------------------------------------------------------------
// This is an overload of format() where no arguments are supplied.
// It returns the formatter string as-is.
//
static String format (const String& fmtstr) __attribute__ ((unused));
static String // FUNCTION
format (const String& fmtstr) // -> String
{
	return fmtstr;
}

// -------------------------------------------------------------------------------------------------
// Prints the formatting result to the given file handle
//
template<typename... Args> FUNCTION
print_to (FILE* fp, const String& fmtstr, Args const& ...args) -> void
{
	std::fprintf (fp, "%s", format (fmtstr, args...).chars());
}

// -------------------------------------------------------------------------------------------------
// Appends the formatting result to the given filename, if opening it succeeds
//
template<typename... argtypes>
void print_to (const String& filename, const String& fmtstr, const argtypes&... args)
{
	FILE* handle;

	if ((handle = fopen (filename, "w+")))
	{
		print_to (handle, fmtstr, args...);
		fclose (handle);
	}
}

// -------------------------------------------------------------------------------------------------
// Prints the formatting result to stdout
//
template<typename... argtypes>
void print (const String& fmtstr, const argtypes&... args)
{
	print_to (stdout, fmtstr, args...);
}