Rack/include/string.hpp

#pragma once
#include <stdarg.h>
#include <vector>

#include <common.hpp>


namespace rack {
/** Supplemental `std::string` functions */
namespace string {


/** Converts a `printf()` format string and optional arguments into a std::string.
Remember that "%s" must reference a `char *`, so use `.c_str()` for `std::string`s, otherwise you will get binary garbage.
*/
__attribute__((format(printf, 1, 2)))
std::string f(const char* format, ...);
std::string fV(const char* format, va_list args);
/** Replaces all characters to lowercase letters */
std::string lowercase(const std::string& s);
/** Replaces all characters to uppercase letters */
std::string uppercase(const std::string& s);
/** Removes whitespace from beginning and end of string. */
std::string trim(const std::string& s);
/** Truncates and adds "..." to the end of a string, not exceeding `len` characters. */
std::string ellipsize(const std::string& s, size_t len);
/** Truncates and adds "..." to the beginning of a string, not exceeding `len` characters. */
std::string ellipsizePrefix(const std::string& s, size_t len);
/** Returns whether a string starts with the given substring. */
bool startsWith(const std::string& str, const std::string& prefix);
/** Returns whether a string ends with the given substring. */
bool endsWith(const std::string& str, const std::string& suffix);

/** Converts a byte array to a Base64-encoded string.
https://en.wikipedia.org/wiki/Base64
*/
std::string toBase64(const uint8_t* data, size_t dataLen);
std::string toBase64(const std::vector<uint8_t>& data);
/** Converts a Base64-encoded string to a byte array.
Throws std::runtime_error if string is invalid.
*/
std::vector<uint8_t> fromBase64(const std::string& str);

struct CaseInsensitiveCompare {
	/** Returns whether `a < b` using case-insensitive lexical comparison. */
	bool operator()(const std::string& a, const std::string& b) const;
};

/** Joins an container (vector, list, etc) of std::strings with an optional separator string.
*/
template <typename TContainer>
std::string join(const TContainer& container, std::string seperator = "") {
	std::string s;
	bool first = true;
	for (const auto& c : container) {
		if (!first)
			s += seperator;
		first = false;
		s += c;
	}
	return s;
}

/** Splits a string into a vector of tokens.
If `maxTokens > 0`, limits the number of tokens.
Tokens do not include the separator string.
Examples:
	split("a+b+c", "+") // {"a", "b", "c"}
	split("abc", "+") // {"abc"}
	split("a++c", "+") // {"a", "", "c"}
	split("", "+") // {}
	split("abc", "") // throws rack::Exception
*/
std::vector<std::string> split(const std::string& s, const std::string& seperator, size_t maxTokens = 0);

/** Formats a UNIX timestamp with a strftime() string. */
std::string formatTime(const char* format, double timestamp);
std::string formatTimeISO(double timestamp);


#if defined ARCH_WIN
/** Performs a Unicode string conversion from UTF-16 to UTF-8.
These are only defined on Windows because the implementation uses Windows' API, and conversion is not needed on other OS's (since everything on Mac and Linux is UTF-8).

std::string and char* variables are considered UTF-8, anywhere in the program.
See https://utf8everywhere.org/ for more information about VCV Rack's philosophy on string encoding, especially section 10 for rules VCV follows for handling text on Windows.
*/
std::string UTF16toUTF8(const std::wstring& w);
std::wstring UTF8toUTF16(const std::string& s);
#endif


} // namespace string
} // namespace rack