class MiniPortileCMake

def cmake_build_type
  (ENV["CMAKE_BUILD_TYPE"] || @cmake_build_type || "Release").dup
end

def cmake_cmd
  (ENV["CMAKE"] || @cmake_command || "cmake").dup
end

def cmake_compile_flags
  # RbConfig::CONFIG['CC'] and RbConfig::CONFIG['CXX'] can contain additional flags, for example
  # "clang++ -std=gnu++11" or "clang -fdeclspec". CMake is just looking for the command name.
  cc_compiler = cc_cmd.split.first
  cxx_compiler = cxx_cmd.split.first
  # needed to ensure cross-compilation with CMake targets the right CPU and compilers
  [
    "-DCMAKE_SYSTEM_NAME=#{cmake_system_name}",
    "-DCMAKE_SYSTEM_PROCESSOR=#{cpu_type}",
    "-DCMAKE_C_COMPILER=#{cc_compiler}",
    "-DCMAKE_CXX_COMPILER=#{cxx_compiler}",
    "-DCMAKE_BUILD_TYPE=#{cmake_build_type}",
  ]
end

def cmake_system_name
  return system_name if system_name
  if MiniPortile.linux?
    'Linux'
  elsif MiniPortile.darwin?
    'Darwin'
  elsif MiniPortile.windows?
    'Windows'
  elsif MiniPortile.freebsd?
    'FreeBSD'
  elsif MiniPortile.openbsd?
    'OpenBSD'
  elsif MiniPortile.solaris?
    'SunOS'
  else
    raise "Unable to set CMAKE_SYSTEM_NAME for #{MiniPortile.target_os}"
  end
end

def configure
  return if configured?
  cache_file = File.join(tmp_path, 'configure.options_cache')
  File.open(cache_file, "w") { |f| f.write computed_options.to_s }
  execute('configure', [cmake_cmd] + computed_options + ["."])
end

def configure_defaults
  [
    generator_defaults,
    cmake_compile_flags,
  ].flatten
end

def configure_prefix
  "-DCMAKE_INSTALL_PREFIX=#{File.expand_path(port_path)}"
end

def configured?
  configure = File.join(work_path, 'configure')
  makefile  = File.join(work_path, 'CMakefile')
  cache_file  = File.join(tmp_path, 'configure.options_cache')
  stored_options  = File.exist?(cache_file) ? File.read(cache_file) : ""
  current_options = computed_options.to_s
  (current_options == stored_options) && newer?(makefile, configure)
end

def cpu_type
  return 'x86_64' if MiniPortile.target_cpu == 'x64'
  MiniPortile.target_cpu
end

def generator_available?(generator_type)
  stdout_str, status = Open3.capture2("#{cmake_cmd} --help")
  raise 'Unable to determine whether CMake supports #{generator_type} Makefile generator' unless status.success?
  stdout_str.include?("#{generator_type} Makefiles")
end

def generator_defaults
  if MiniPortile.mswin? && generator_available?('NMake')
    ['-G', 'NMake Makefiles']
  elsif MiniPortile.mingw? && generator_available?('MSYS')
    ['-G', 'MSYS Makefiles']
  else
    []
  end
end

def initialize(name, version, **kwargs)
  super(name, version, **kwargs)
  @cmake_command = kwargs[:cmake_command]
  @cmake_build_type = kwargs[:cmake_build_type]
end

def make_cmd
  return "nmake" if MiniPortile.mswin?
  super
end