#include <memory>
#include <getopt.h>
#include <iostream>
#include <sstream>

#include <qrcodegen.hpp>

#include "util.hpp"
#include "QR.hpp"

// Version is injected through cmake
constexpr const char* VERSION = "@qr_VERSION@";

void printHelp() {
	std::string helpText = R"EOF(

qr is a tool for generating QR codes from the commandline

Usage: qr [OPTION]... --input "data to encapsulate"

*Caveats*
  With no `--input` parameter defined, read STDIN

  In pixel based renderers (i.e. PNG), the output code may not be exactly
  centered, as the amount of segment may not correspond to the specified
  output size.

Options:
  -f --format     output file format. can be one of "cli, png, svg, jpg, bmp"
  -h --help       show this help
  -i --input      take data from this argument instead of stdin
  -o --output     output file name without extension
  -s --size       desired output file size in pixels
  -t --type       output QR code type. can be one of "small, medium, large"
  -v --version    shows version info

Examples:
  qr -i "this is from parameter" -f png -s 512 -o my_qrcode_file

  echo "this is from stdin" | qr -t small -f png -s 512 -o my_qrcode_file_with_low_ecc

Copyright:
  (C) 2023, MikO <miko@massivedynamic.eu>

*License*
  Released under MIT license

Report bugs and issues at out issue tracker:
  https://git.mike-ochmann.de/MassiveDynamic/qr/issues
	)EOF";
	std::cout << "qr " << VERSION;
	std::cout << helpText << std::endl;
}

int main(int argc, char* argv[]) {
	if (argc < 1) {
		printHelp();
		exit(1);
	}
	const option options[] = {
		{"help",    no_argument,       nullptr, 'h'},
		{"input",   required_argument, nullptr, 'i'},
		{"output",  required_argument, nullptr, 'o'},
		{"size",    required_argument, nullptr, 's'},
		{"type",    required_argument, nullptr, 't'},
		{"format",  required_argument, nullptr, 'f'},
		{"version", no_argument,       nullptr, 'v'},
		{nullptr}
	};

	std::string outputFile;
	std::string paramData;
	size_t segmentSize            = 0;
	bool fromStdin                = true;
	bool anyParameterSet          = false;
	qrcodegen::QrCode::Ecc type   = qrcodegen::QrCode::Ecc::LOW;
	massivedynamic::Format format = massivedynamic::Format::CONSOLE;

	for(;;) {
		int index  = -1;
		int result = getopt_long(argc, argv, "vho:s:t:f:i:", options, &index);
		
		if (result == -1)
			break;

		anyParameterSet = true;
		const option* opt = &options[index];
		UNUSED(opt);
		switch(result) {
			case 'o': {
				if (strlen(optarg) > 0)
					outputFile = optarg;
				break;
			}
			case 's': {
				segmentSize = std::atoi(optarg);
				break;
			}
			case 't': {
				std::string value = optarg;
				if (value == "small")
					type = qrcodegen::QrCode::Ecc::LOW;
				else if (value == "medium")
					type = qrcodegen::QrCode::Ecc::MEDIUM;
				else if (value == "large")
					type = qrcodegen::QrCode::Ecc::HIGH;
				else {
					std::cerr << "ERROR: type (-t, --type) has to be one of 'small', 'medium' or 'large'" << std::endl;
					printHelp();
					return 1;
				}
				break;
			}
			case 'f': {
				std::string value = optarg;
				static_assert(massivedynamic::FormatLength == 5, "exhaustive formats: did you miss to add something here?");
				if (value == "cli")
					format = massivedynamic::Format::CONSOLE;
				else if (value == "svg")
					format = massivedynamic::Format::SVG;
				else if (value == "png")
					format = massivedynamic::Format::PNG;
				else if (value == "jpg")
					format = massivedynamic::Format::JPG;
				else if (value == "bmp")
					format = massivedynamic::Format::BMP;
				else {
					printHelp();
					return 1;
				}
				break;
			}
			case 'i': {
				fromStdin = false;
				paramData = optarg;
				break;
			}
			case 'v': {
				std::cout << "qr " << VERSION << std::endl;
				exit(0);
			}
			case 'h':
			default:
				printHelp();
				return 0;
		}
	}

 	std::string line;
	std::stringstream data;
 
	if (fromStdin) {
		if (!isatty(fileno(stdin))) {
			while (std::getline(std::cin, line)) {
				if (std::cin.eof() || line.empty()) {
					std::cin.clear();
					break;
				}
				data << line;
			}
		}

		if (isatty(fileno(stdin)) || data.str().empty()) {
			std::cerr << "ERROR: no data from stdinput." << std::endl;
			if(!anyParameterSet)
				printHelp();
			exit(1);
		}
	} else
		data << paramData;

	if (data.str().empty()) {
		std::cerr << "ERROR: input data is empty" << std::endl;
		exit(1);
	}

	if ((format == massivedynamic::Format::PNG || format == massivedynamic::Format::SVG) && outputFile.empty()) {
		std::cerr << "ERROR: output file name (-o, --output) can not be empty" << std::endl;
		return 1;
	}

	std::unique_ptr<massivedynamic::QR> qr = std::make_unique<massivedynamic::QR>(data.str(), outputFile, segmentSize, type);
	qr->render(format);

	return 0;
}