// -*- c++ -*-
// Distributed under the BSD 2-Clause License.
// See accompanying file LICENSE for details.
#include "configure.h"

#include <iostream>
#include <filesystem>
#include <fstream>

#include <getoptpp/getoptpp.hpp>

#include "settings.h"
#include "execute.h"
#include "libcppbuild.h"
#include "tasks.h"

std::filesystem::path configurationFile("configuration.cc");
std::filesystem::path configHeaderFile("config.h");

const std::map<std::string, std::string> default_configuration{};
const std::map<std::string, std::string>& __attribute__((weak)) configuration()
{
	return default_configuration;
}

bool hasConfiguration(const std::string& key)
{
	const auto& c = configuration();
	return c.find(key) != c.end();
}

const std::string& getConfiguration(const std::string& key,
                                    const std::string& defaultValue)
{
	const auto& c = configuration();
	if(hasConfiguration(key))
	{
		return c.at(key);
	}

	return defaultValue;
}


/*
Configuration:
  -h, --help              display this help and exit
      --help=short        display options specific to this package
      --help=recursive    display the short help of all the included packages
  -V, --version           display version information and exit
  -q, --quiet, --silent   do not print `checking ...' messages
      --cache-file=FILE   cache test results in FILE [disabled]
  -C, --config-cache      alias for `--cache-file=config.cache'
  -n, --no-create         do not create output files
      --srcdir=DIR        find the sources in DIR [configure dir or `..']

Installation directories:
  --prefix=PREFIX         install architecture-independent files in PREFIX
                          [/usr/local]
  --exec-prefix=EPREFIX   install architecture-dependent files in EPREFIX
                          [PREFIX]

By default, `make install' will install all the files in
`/usr/local/bin', `/usr/local/lib' etc.  You can specify
an installation prefix other than `/usr/local' using `--prefix',
for instance `--prefix=$HOME'.

For better control, use the options below.

Fine tuning of the installation directories:
  --bindir=DIR            user executables [EPREFIX/bin]
  --sbindir=DIR           system admin executables [EPREFIX/sbin]
  --libexecdir=DIR        program executables [EPREFIX/libexec]
  --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
  --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
  --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
  --libdir=DIR            object code libraries [EPREFIX/lib]
  --includedir=DIR        C header files [PREFIX/include]
  --oldincludedir=DIR     C header files for non-gcc [/usr/include]
  --datarootdir=DIR       read-only arch.-independent data root [PREFIX/share]
  --datadir=DIR           read-only architecture-independent data [DATAROOTDIR]
  --infodir=DIR           info documentation [DATAROOTDIR/info]
  --localedir=DIR         locale-dependent data [DATAROOTDIR/locale]
  --mandir=DIR            man documentation [DATAROOTDIR/man]
  --docdir=DIR            documentation root [DATAROOTDIR/doc/drumgizmo]
  --htmldir=DIR           html documentation [DOCDIR]
  --dvidir=DIR            dvi documentation [DOCDIR]
  --pdfdir=DIR            pdf documentation [DOCDIR]
  --psdir=DIR             ps documentation [DOCDIR]

Program names:
  --program-prefix=PREFIX            prepend PREFIX to installed program names
  --program-suffix=SUFFIX            append SUFFIX to installed program names
  --program-transform-name=PROGRAM   run sed PROGRAM on installed program names

System types:
  --build=BUILD     configure for building on BUILD [guessed]
  --host=HOST       cross-compile to build programs to run on HOST [BUILD]

Optional Features:
  --disable-option-checking  ignore unrecognized --enable/--with options
  --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
  --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]
  --enable-silent-rules   less verbose build output (undo: "make V=1")
  --disable-silent-rules  verbose build output (undo: "make V=0")
  --enable-dependency-tracking
                          do not reject slow dependency extractors
  --disable-dependency-tracking
                          speeds up one-time build
  --enable-shared[=PKGS]  build shared libraries [default=yes]
  --enable-static[=PKGS]  build static libraries [default=yes]
  --enable-fast-install[=PKGS]
                          optimize for fast installation [default=yes]
  --disable-libtool-lock  avoid locking (might break parallel builds)
  --disable-largefile     omit support for large files
  --enable-gui=backend    Use specified gui backend. Can be x11, win32, cocoa,
                          pugl-x11, pugl-win32, pugl-cocoa or auto
                          [default=auto]
  --enable-custom-channel-count=count
                          Compile with specified number of output channels
                          [default=16]
  --enable-lv2            Compile the LV2 plugin [default=no]
  --enable-vst            Compile the VST plugin [default=no]
  --enable-cli            Compile the command line interface [default=yes]
  --disable-input-dummy   Disable input dummy plugin [default=enabled]
  --disable-input-test    Disable input test plugin [default=enabled]
  --disable-input-jackmidi
                          Disable input jackmidi plugin [default=enabled]
  --disable-input-alsamidi
                          Disable input alsamidi plugin [default=enabled]
  --disable-input-midifile
                          Disable input midifile plugin [default=enabled]
  --disable-input-oss     Disable input oss plugin [enabled by default on
                          FreeBSD, disabled otherwise]
  --disable-output-dummy  Disable output dummy plugin [default=enabled]
  --disable-output-jackaudio
                          Disable output jack plugin [default=enabled]
  --disable-output-alsa   Disable output alsa plugin [default=enabled]
  --disable-output-wavfile
                          Disable output wavfile plugin [default=enabled]
  --disable-output-oss    Disable output oss plugin [enabled by default on
                          FreeBSD, disabled otherwise]
  --enable-sse=level      Enable SSE Level 1, 2, 3 or auto [default=auto]

Optional Packages:
  --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
  --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no)
  --with-pic[=PKGS]       try to use only PIC/non-PIC objects [default=use
                          both]
  --with-aix-soname=aix|svr4|both
                          shared library versioning (aka "SONAME") variant to
                          provide on AIX, [default=aix].
  --with-gnu-ld           assume the C compiler uses GNU ld [default=no]
  --with-sysroot[=DIR]    Search for dependent libraries within DIR (or the
                          compiler's sysroot if not specified).
  --with-debug            Build with debug support
  --with-nls              Build with nls support (default nls enabled)
  --with-test             Build unit tests
  --with-lv2dir=DIR       Use DIR as the lv2 plugin directory
                          [default=LIBDIR/lv2]
  --with-vst-sources      Point this to the vstsdk24 directory

Some influential environment variables:
  CXX         C++ compiler command
  CXXFLAGS    C++ compiler flags
  LDFLAGS     linker flags, e.g. -L<lib dir> if you have libraries in a
              nonstandard directory <lib dir>
  LIBS        libraries to pass to the linker, e.g. -l<library>
  CPPFLAGS    (Objective) C/C++ preprocessor flags, e.g. -I<include dir> if
              you have headers in a nonstandard directory <include dir>
  OBJC        Objective C compiler command
  OBJCFLAGS   Objective C compiler flags
  OBJCXX      Objective C++ compiler command
  OBJCXXFLAGS Objective C++ compiler flags
  CC          C compiler command
  CFLAGS      C compiler flags
  LT_SYS_LIBRARY_PATH
              User-defined run-time library search path.
  CPP         C preprocessor
  CXXCPP      C++ preprocessor
  PKG_CONFIG  path to pkg-config utility
  PKG_CONFIG_PATH
              directories to add to pkg-config's search path
  PKG_CONFIG_LIBDIR
              path overriding pkg-config's built-in search path
  X11_CFLAGS  C compiler flags for X11, overriding pkg-config
  X11_LIBS    linker flags for X11, overriding pkg-config
  XEXT_CFLAGS C compiler flags for XEXT, overriding pkg-config
  XEXT_LIBS   linker flags for XEXT, overriding pkg-config
  LV2_CFLAGS  C compiler flags for LV2, overriding pkg-config
  LV2_LIBS    linker flags for LV2, overriding pkg-config
  SMF_CFLAGS  C compiler flags for SMF, overriding pkg-config
  SMF_LIBS    linker flags for SMF, overriding pkg-config
  SNDFILE_CFLAGS
              C compiler flags for SNDFILE, overriding pkg-config
  SNDFILE_LIBS
              linker flags for SNDFILE, overriding pkg-config
  JACK_CFLAGS C compiler flags for JACK, overriding pkg-config
  JACK_LIBS   linker flags for JACK, overriding pkg-config
  ALSA_CFLAGS C compiler flags for ALSA, overriding pkg-config
  ALSA_LIBS   linker flags for ALSA, overriding pkg-config

Use these variables to override the choices made by `configure' or to help
it to find libraries and programs with nonstandard names/locations.

Report bugs to the package provider.
*/
int configure(int argc, char* argv[])
{
	Settings settings;

	settings.builddir = "build";

	std::string cmd_str;
	for(int i = 0; i < argc; ++i)
	{
		if(i > 0)
		{
			cmd_str += " ";
		}
		cmd_str += argv[i];
	}

	dg::Options opt;
	int key{256};

	std::string build_arch;
	std::string build_path;
	std::string host_arch;
	std::string host_path;

	opt.add("build-dir", required_argument, 'b',
	        "Set output directory for build files (default: '" +
	        settings.builddir + "').",
	        [&]() {
		        settings.builddir = optarg;
		        return 0;
	        });

	opt.add("verbose", no_argument, 'v',
	        "Be verbose. Add multiple times for more verbosity.",
	        [&]() {
		        settings.verbose++;
		        return 0;
	        });

	opt.add("build", required_argument, key++,
	        "Configure for building on specified architecture.",
	        [&]() {
		        build_arch = optarg;
		        return 0;
	        });

	opt.add("build-path", required_argument, key++,
	        "Set path to build tool-chain.",
	        [&]() {
		        build_path = optarg;
		        return 0;
	        });

	opt.add("host", required_argument, key++,
	        "Cross-compile to build programs to run on specified architecture.",
	        [&]() {
		        host_arch = optarg;
		        return 0;
	        });

	opt.add("host-path", required_argument, key++,
	        "Set path to cross-compile tool-chain.",
	        [&]() {
		        host_path = optarg;
		        return 0;
	        });

	opt.add("help", no_argument, 'h',
	        "Print this help text.",
	        [&]() {
		        std::cout << "configure usage stuff\n";
		        opt.help();
		        exit(0);
		        return 0;
	        });

	opt.process(argc, argv);

	if(host_arch.empty())
	{
		host_arch = build_arch;
	}

	auto tasks = getTasks(settings);

	bool needs_cpp{false};
	bool needs_c{false};
	bool needs_ar{false};
	bool needs_asm{false};
	for(const auto& task :tasks)
	{
		switch(task->sourceLanguage())
		{
		case Language::Auto:
			std::cerr << "TargetLanguage not deduced!\n";
			exit(1);
			break;
		case Language::C:
			needs_cpp = false;
			break;
		case Language::Cpp:
			needs_c = true;
			break;
		case Language::Asm:
			needs_asm = true;
			break;
		}
	}

	// CC=clang
	// CXX=clang++

	std::string path_env = std::getenv("PATH");
	std::cout << path_env << "\n";

	std::vector<std::string> paths;

	{
		std::stringstream ss(path_env);
		std::string path;
		while (std::getline(ss, path, ':'))
		{
			paths.push_back(path);
		}
	}
	for(const auto& path_str : paths)
	{
		std::filesystem::path path(path_str);
		auto gcc = path / "gcc";
		if(std::filesystem::exists(gcc))
		{
			std::cout << "Found file gcc in path: " << path << "\n";
			auto perms = std::filesystem::status(gcc).permissions();
			if((perms & std::filesystem::perms::owner_exec) != std::filesystem::perms::none)
			{
				std::cout << " - executable by owner\n";
			}
			if((perms & std::filesystem::perms::group_exec) != std::filesystem::perms::none)
			{
				std::cout << " - executable by group\n";
			}
			if((perms & std::filesystem::perms::others_exec) != std::filesystem::perms::none)
			{
				std::cout << " - executable by others\n";
			}
		}
	}
	exit(0);

	{
		std::ofstream istr(configurationFile);
		istr << "#include \"libcppbuild.h\"\n\n";
		istr << "const std::map<std::string, std::string>& configuration()\n";
		istr << "{\n";
		istr << "	static std::map<std::string, std::string> c =\n";
		istr << "	{\n";
		istr << "		{ \"cmd\", \"" << cmd_str << "\" },\n";
		istr << "		{ \"" << cfg::builddir << "\", \"" << settings.builddir << "\" },\n";
		istr << "		{ \"" << cfg::target_cc << "\", \"/usr/bin/gcc\" },\n";
		istr << "		{ \"" << cfg::target_cpp << "\", \"/usr/bin/g++\" },\n";
		istr << "		{ \"" << cfg::target_ar << "\", \"/usr/bin/ar\" },\n";
		istr << "		{ \"" << cfg::target_ld << "\", \"/usr/bin/ld\" },\n";
		istr << "		{ \"" << cfg::host_cc << "\", \"/usr/bin/gcc\" },\n";
		istr << "		{ \"" << cfg::host_cpp << "\", \"/usr/bin/g++\" },\n";
		istr << "		{ \"" << cfg::host_ar << "\", \"/usr/bin/ar\" },\n";
		istr << "		{ \"" << cfg::host_ld << "\", \"/usr/bin/ld\" },\n";
		istr << "	};\n";
		istr << "	return c;\n";
		istr << "}\n";
	}

	{
		std::ofstream istr(configHeaderFile);
		istr << "#pragma once\n\n";
		istr << "#define HAS_FOO 1\n";
		istr << "//#define HAS_BAR 1\n";
	}

	return 0;
}