# Copyright 2017 The Fuchsia Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Recipe for building Clang toolchain."""

from recipe_engine.config import Enum, ReturnSchema, Single
from recipe_engine.recipe_api import Property

import re


DEPS = [
  'infra/cipd',
  'infra/git',
  'infra/gitiles',
  'infra/goma',
  'infra/gsutil',
  'infra/hash',
  'infra/jiri',
  'recipe_engine/context',
  'recipe_engine/file',
  'recipe_engine/json',
  'recipe_engine/path',
  'recipe_engine/platform',
  'recipe_engine/properties',
  'recipe_engine/python',
  'recipe_engine/raw_io',
  'recipe_engine/step',
  'recipe_engine/tempfile',
]

TARGETS = [
  ('aarch64', 'arm64'),
  ('x86_64', 'x64'),
]

LLVM_PROJECT_GIT = 'https://fuchsia.googlesource.com/third_party/llvm-project'
LIBXML2_GIT = 'https://fuchsia.googlesource.com/third_party/libxml2'
ZLIB_GIT = 'https://fuchsia.googlesource.com/third_party/zlib'

PROPERTIES = {
  'url': Property(kind=str, help='Git repository URL', default=LLVM_PROJECT_GIT),
  'ref': Property(kind=str, help='Git reference', default='refs/heads/master'),
  'revision': Property(kind=str, help='Revision', default=None),
}


def RunSteps(api, url, ref, revision):
  api.gitiles.ensure_gitiles()
  api.goma.ensure_goma()
  api.gsutil.ensure_gsutil()
  api.jiri.ensure_jiri()

  if not revision:
    revision = api.gitiles.refs(url).get(ref, None)
  cipd_pkg_name = 'fuchsia/clang/' + api.cipd.platform_suffix()
  step = api.cipd.search(cipd_pkg_name, 'git_revision:' + revision)
  if step.json.output['result']:
    api.step('Package is up-to-date', cmd=None)
    return

  with api.step.nest('ensure_packages'):
    with api.context(infra_steps=True):
      cipd_dir = api.path['start_dir'].join('cipd')
      packages = {
        'infra/cmake/${platform}': 'version:3.9.2',
        'infra/ninja/${platform}': 'version:1.8.2',
        'fuchsia/clang/${platform}': 'goma',
      }
      if api.platform.name == 'linux':
        packages.update({
          'fuchsia/sysroot/${platform}': 'latest'
        })
      api.cipd.ensure(cipd_dir, packages)

  with api.step.nest('ensure_sdk'):
    with api.context(infra_steps=True):
      sdk_dir = api.path['start_dir'].join('sdk')
      packages = {
        'fuchsia/sdk/${platform}': 'latest',
      }
      api.cipd.ensure(sdk_dir, packages)

  staging_dir = api.path.mkdtemp('clang')
  pkg_name = 'clang-%s' % api.platform.name.replace('mac', 'darwin')
  pkg_dir = staging_dir.join(pkg_name)
  api.file.ensure_directory('create pkg dir', pkg_dir)

  with api.context(infra_steps=True):
    llvm_dir = api.path['start_dir'].join('llvm-project')
    api.git.checkout(url, llvm_dir, ref=revision, submodules=True)

    zlib_dir = api.path['start_dir'].join('zlib')
    api.git.checkout(ZLIB_GIT, zlib_dir, ref='refs/tags/v1.2.9')

    libxml2_dir = api.path['start_dir'].join('libxml2')
    api.git.checkout(LIBXML2_GIT, libxml2_dir, ref='refs/tags/v2.9.8')

  lib_install_dir = staging_dir.join('lib_install')
  api.file.ensure_directory('create lib_install_dir', lib_install_dir)

  if api.platform.name == 'linux':
    host_sysroot = cipd_dir
  elif api.platform.name == 'mac':
    # TODO(IN-148): Eventually use our own hermetic sysroot as for Linux.
    step_result = api.step(
        'xcrun', ['xcrun', '--show-sdk-path'],
        stdout=api.raw_io.output(name='sdk-path', add_output_log=True),
        step_test_data=lambda: api.raw_io.test_api.stream_output(
            '/some/xcode/path'))
    host_sysroot = step_result.stdout.strip()
  else: # pragma: no cover
    assert false, "unsupported platform"

  with api.goma.build_with_goma():
    vars = {
      'CC': '%s %s' % (api.goma.goma_dir.join('gomacc'), cipd_dir.join('bin', 'clang')),
      'CFLAGS': '-O3 -fPIC --sysroot=%s' % host_sysroot,
      'AR': cipd_dir.join('bin', 'llvm-ar'),
      'NM': cipd_dir.join('bin', 'llvm-nm'),
      'RANLIB': cipd_dir.join('bin', 'llvm-ranlib'),
    }

    # build zlib
    build_dir = staging_dir.join('zlib_build_dir')
    api.file.ensure_directory('create zlib build dir', build_dir)

    with api.step.nest('zlib'), api.context(cwd=build_dir, env=vars):
      api.step('configure', [
        zlib_dir.join('configure'),
        '--prefix=',
        '--static',
      ])
      api.step('build', ['make', '-j%d' % api.goma.recommended_goma_jobs])
      api.step('install', ['make', 'install', 'DESTDIR=%s' % lib_install_dir])

    # build libxml2
    build_dir = staging_dir.join('libxml2_build_dir')
    api.file.ensure_directory('create libxml2 build dir', build_dir)

    with api.step.nest('libxml2'), api.context(cwd=build_dir):
      with api.context(cwd=libxml2_dir):
        api.step('autoconf', ['autoreconf', '-i', '-f'])
      api.step('configure', [
        libxml2_dir.join('configure'),
        '--prefix=',
        '--enable-static',
        '--disable-shared',
        '--with-zlib=%s' % lib_install_dir,
        '--without-icu',
        '--without-lzma',
        '--without-python',
      ] + ['%s=%s' % (k, v) for k, v in vars.iteritems()])
      api.step('build', ['make', '-j%d' % api.goma.recommended_goma_jobs])
      api.step('install', ['make', 'install', 'DESTDIR=%s' % lib_install_dir])

    # build clang+llvm
    build_dir = staging_dir.join('llvm_build_dir')
    api.file.ensure_directory('create llvm build dir', build_dir)

    extra_options = {
      'linux': [
        # BOOTSTRAP_ prefixed flags are passed to the second stage compiler.
        '-DBOOTSTRAP_CMAKE_C_FLAGS=-I%s -I%s' % (lib_install_dir.join('include'), lib_install_dir.join('include', 'libxml2')),
        '-DBOOTSTRAP_CMAKE_CXX_FLAGS=-I%s -I%s' % (lib_install_dir.join('include'), lib_install_dir.join('include', 'libxml2')),
        '-DBOOTSTRAP_CMAKE_SHARED_LINKER_FLAGS=-static-libstdc++ -ldl -lpthread -L%s -L%s' % (cipd_dir.join('lib'), lib_install_dir.join('lib')),
        '-DBOOTSTRAP_CMAKE_MODULE_LINKER_FLAGS=-static-libstdc++ -ldl -lpthread -L%s -L%s' % (cipd_dir.join('lib'), lib_install_dir.join('lib')),
        '-DBOOTSTRAP_CMAKE_EXE_LINKER_FLAGS=-static-libstdc++ -ldl -lpthread -L%s -L%s' % (cipd_dir.join('lib'), lib_install_dir.join('lib')),
        '-DBOOTSTRAP_CMAKE_SYSROOT=%s' % cipd_dir,
        # Unprefixed flags are only used by the first stage compiler.
        '-DCMAKE_EXE_LINKER_FLAGS=-static-libstdc++ -ldl -lpthread -L%s' % cipd_dir.join('lib'),
        '-DCMAKE_EXE_SHARED_FLAGS=-static-libstdc++ -ldl -lpthread -L%s' % cipd_dir.join('lib'),
        '-DCMAKE_SYSROOT=%s' % cipd_dir,
      ],
      'mac': [],
    }[api.platform.name]

    for tc_arch, gn_arch in TARGETS:
      extra_options.extend([
        '-DSTAGE2_FUCHSIA_%s_SYSROOT=%s' % (tc_arch, sdk_dir.join('arch', gn_arch, 'sysroot')),
        '-DSTAGE2_FUCHSIA_%s_C_FLAGS=-I%s' % (tc_arch, sdk_dir.join('pkg', 'fdio', 'include')),
        '-DSTAGE2_FUCHSIA_%s_CXX_FLAGS=-I%s' % (tc_arch, sdk_dir.join('pkg', 'fdio', 'include')),
        '-DSTAGE2_FUCHSIA_%s_LINKER_FLAGS=-L%s' % (tc_arch, sdk_dir.join('arch', gn_arch, 'lib')),
      ])

    with api.step.nest('clang'), api.context(cwd=build_dir):
      api.step('configure', [
        cipd_dir.join('bin', 'cmake'),
        '-GNinja',
        '-DCMAKE_C_COMPILER_LAUNCHER=%s' % api.goma.goma_dir.join('gomacc'),
        '-DCMAKE_CXX_COMPILER_LAUNCHER=%s' % api.goma.goma_dir.join('gomacc'),
        '-DCMAKE_ASM_COMPILER_LAUNCHER=%s' % api.goma.goma_dir.join('gomacc'),
        '-DCMAKE_C_COMPILER=%s' % cipd_dir.join('bin', 'clang'),
        '-DCMAKE_CXX_COMPILER=%s' % cipd_dir.join('bin', 'clang++'),
        '-DCMAKE_ASM_COMPILER=%s' % cipd_dir.join('bin', 'clang'),
        '-DCMAKE_MAKE_PROGRAM=%s' % cipd_dir.join('ninja'),
        '-DCMAKE_INSTALL_PREFIX=',
        '-DLLVM_ENABLE_PROJECTS=clang;lld',
        '-DLLVM_ENABLE_RUNTIMES=compiler-rt;libcxx;libcxxabi;libunwind',
      ] + extra_options + [
        '-C', llvm_dir.join('clang', 'cmake', 'caches', 'Fuchsia.cmake'),
        llvm_dir.join('llvm'),
      ])
      api.step('build', [cipd_dir.join('ninja'), 'stage2-distribution'])
      # TODO: we should be running stage2-check-all
      api.step('check-llvm', [cipd_dir.join('ninja'), 'stage2-check-llvm'])
      api.step('check-clang', [cipd_dir.join('ninja'), 'stage2-check-clang'])
      with api.context(env={'DESTDIR': pkg_dir}):
        api.step('install',
                 [cipd_dir.join('ninja'), 'stage2-install-distribution'])

  # use first rather than second stage clang just in case we're cross-compiling
  step_result = api.step('clang version',
      [build_dir.join('bin', 'clang'), '--version'],
      stdout=api.raw_io.output())
  m = re.search(r'version ([0-9.-]+)', step_result.stdout)
  assert m, 'Cannot determine Clang version'
  clang_version = m.group(1)

  # TODO(TO-471): Ideally this would be done by the cmake build itself.
  manifest_format = ''
  for soname in [
      'libclang_rt.asan-{arch}.so',
      'libclang_rt.ubsan_standalone-{arch}.so',
      'libclang_rt.scudo-{arch}.so',
  ]:
    manifest_format += ('lib/%s=clang/{clang_version}/lib/fuchsia/%s\n' %
                        (soname, soname))
  for prefix in ('', 'asan/'):
    for soname in [
        'libc++.so.2',
        'libc++abi.so.1',
        'libunwind.so.1',
    ]:
      manifest_format += ('lib/%s={arch}-fuchsia/lib/%s\n' %
                         (prefix + soname, prefix + soname))
  for tc_arch, gn_arch in TARGETS:
    manifest_file = '%s-fuchsia.manifest' % tc_arch
    api.file.write_text('write %s' % manifest_file,
                        pkg_dir.join('lib', manifest_file),
                        manifest_format.format(arch=tc_arch,
                                               clang_version=clang_version))

  pkg_def = api.cipd.PackageDefinition(
      package_name=cipd_pkg_name,
      package_root=pkg_dir,
      install_mode='copy')
  pkg_def.add_dir(pkg_dir)
  pkg_def.add_version_file('.versions/clang.cipd_version')

  cipd_pkg_file = api.path['cleanup'].join('clang.cipd')

  api.cipd.build_from_pkg(
      pkg_def=pkg_def,
      output_package=cipd_pkg_file,
  )
  step_result = api.cipd.register(
      package_name=cipd_pkg_name,
      package_path=cipd_pkg_file,
      refs=['latest'],
      tags={
        'version': clang_version,
        'git_repository': LLVM_PROJECT_GIT,
        'git_revision': revision,
      },
  )

  api.gsutil.upload(
      'fuchsia',
      cipd_pkg_file,
      api.gsutil.join('clang', api.cipd.platform_suffix(), step_result.json.output['result']['instance_id']),
      unauthenticated_url=True
  )


def GenTests(api):
  revision = '75b05681239cb309a23fcb4f8864f177e5aa62da'
  version = 'clang version 5.0.0 (trunk 302207) (llvm/trunk 302209)'
  for platform in ('linux', 'mac'):
    yield (api.test(platform) +
           api.platform.name(platform) +
           api.gitiles.refs('refs', ('refs/heads/master', revision)))
    yield (api.test(platform + '_new') +
           api.platform.name(platform) +
           api.gitiles.refs('refs', ('refs/heads/master', revision)) +
           api.step_data('clang version', api.raw_io.stream_output(version)) +
           api.step_data('cipd search fuchsia/clang/' + platform + '-amd64 ' +
                         'git_revision:' + revision,
                         api.json.output({'result': []})))