# This Source Code Form is subject to the terms of the Mozilla Public License,
# v. 2.0. If a copy of the MPL was not distributed with this file, You can
# obtain one at https://mozilla.org/MPL/2.0/.
# frozen_string_literal: true

require 'pathname'
require 'rake/clean'

CLEAN.include 'build/boot', 'build/valid'

file 'build/build.ninja' => ['build'] do |t|
  File.open t.name, 'w' do |f|
    f << <<~NINJA
      builddir = build
      cflags = -fpie -g

      rule cc
        command = gcc $cflags -nostdlib -o $out $in

      rule as
        command = gcc $cflags -c -o $out $in

      rule link1
        command = ld -o $out $in

      rule link2
        command = ld -o $out --dynamic-linker /lib32/ld-linux-riscv32-ilp32d.so.1 /usr/lib/crt1.o /usr/lib/crti.o -lc $in /usr/lib/crtn.o

      rule bootstrap
        command = $bootstrap < \$in > \$out
    NINJA
    f << <<~NINJA

      build build/boot/stage1/cl: cc boot/stage1.s
      build build/valid/stage1/cl.s: bootstrap boot/stage1.s | build/boot/stage1/cl
        bootstrap = build/boot/stage1/cl

      build build/valid/stage1/cl.o: as build/valid/stage1/cl.s
      build build/valid/stage1/cl: link1 build/valid/stage1/cl.o
    NINJA
    STAGES.each do |stage|
      stage_number = stage.delete_prefix('stage').to_i

      arguments_path = Pathname.new('boot') + stage + 'linker.arg'
      if arguments_path.exist?
        link = 'link2'
      else
        link = 'link1'
      end
      boot_stage = "build/boot/stage#{stage_number}"
      valid_stage = "build/valid/stage#{stage_number}"
      f << <<~NINJA

        build #{boot_stage}/cl.s: bootstrap boot/stage#{stage_number}/cl.elna | build/valid/stage#{stage_number.pred}/cl
          bootstrap = build/valid/stage#{stage_number.pred}/cl

        build #{boot_stage}/cl.o: as #{boot_stage}/cl.s
        build #{boot_stage}/cl: #{link} #{boot_stage}/cl.o

        build #{valid_stage}/cl.s: bootstrap boot/stage#{stage_number}/cl.elna | #{boot_stage}/cl
          bootstrap = build/boot/stage#{stage_number}/cl

        build #{valid_stage}/cl.o: as #{valid_stage}/cl.s
        build #{valid_stage}/cl: #{link} #{valid_stage}/cl.o
      NINJA
    end
    f << <<~NINJA

      default build/valid/#{STAGES.last}/cl
    NINJA
  end
end

file "build/valid/#{STAGES.last}/cl" => 'build/build.ninja' do |t|
  sh 'ninja', '-f', t.prerequisites.first
end