require 'fileutils'

describe Rscons do
  FileUtils.rm_rf('build_test')

  def setup_testdir(files, &blk)
    FileUtils.mkdir_p('build_test')
    files.each do |fname|
      src = "spec/build_items/#{fname}"
      dst = "build_test/#{fname}"
      FileUtils.mkdir_p(File.dirname(dst))
      FileUtils.cp_r(src, dst)
    end
    Dir.chdir('build_test', &blk)
    FileUtils.rm_rf('build_test')
  end

  def clear_cache
    Rscons::Cache.open.clear
  end

  before do
    $stdout.stub(:puts) { nil }
    clear_cache
  end

  ###########################################################################
  # Build Tests
  ###########################################################################

  it 'builds a C program with one source file' do
    setup_testdir(['simple.c']) do
      env = Rscons::Environment.new
      env.Program('simple', 'simple.c')
      File.exist?('simple.o').should be_true
      `./simple`.should =~ /This is a simple C program/
    end
  end

  it 'supports short echo mode' do
    $stdout.should_receive(:puts).once.with('CC simple.o')
    $stdout.should_receive(:puts).once.with('LD simple')
    setup_testdir(['simple.c']) do
      env = Rscons::Environment.new(echo: :short)
      env.Program('simple', 'simple.c')
      File.exist?('simple.o').should be_true
      `./simple`.should =~ /This is a simple C program/
    end
  end

  it 'does not rebuild the program if no sources changed' do
    $stdout.should_receive(:puts).once.with("gcc -c -o simple.o -MMD -MF simple.mf simple.c")
    $stdout.should_receive(:puts).once.with('gcc -o simple simple.o')
    setup_testdir(['simple.c']) do
      env = Rscons::Environment.new
      env.Program('simple', 'simple.c')
      env.Program('simple', 'simple.c')
    end
  end

  it 'rebuilds the application when the source file changes' do
    setup_testdir(['simple.c']) do
      env = Rscons::Environment.new
      env.Program('simple', 'simple.c')
      `./simple`.should =~ /This is a simple C program/
      c = File.read('simple.c')
      File.open('simple.c', 'w') do |fh|
        fh.puts c.sub('simple', 'modified')
      end
      clear_cache
      env.Program('simple', 'simple.c')
      `./simple`.should =~ /This is a modified C program/
    end
  end

  it 'builds a C program with a header file' do
    setup_testdir(['header.c', 'header.h']) do
      env = Rscons::Environment.new
      env.Program('header', 'header.c')
      File.exist?('header.o').should be_true
      `./header`.should =~ /The value is 33/
    end
  end

  it 'rebuilds a C source when a header it uses changes' do
    setup_testdir(['header.c', 'header.h']) do
      env = Rscons::Environment.new
      env.Program('header', 'header.c')
      File.exist?('header.o').should be_true
      `./header`.should =~ /The value is 33/
      h = File.read('header.h')
      File.open('header.h', 'w') do |fh|
        fh.puts h.sub('33', '42')
      end
      clear_cache
      env.Program('header', 'header.c')
      `./header`.should =~ /The value is 42/
    end
  end
end