# Copyright (c) 2016, 2017 ARM Limited.
#
# SPDX-License-Identifier: MIT
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to
# deal in the Software without restriction, including without limitation the
# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
# sell copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
import collections
import os.path
import re
import subprocess
import SCons

VERSION = "v17.04"
SONAME_VERSION="1.0.0"

vars = Variables('scons')
vars.Add(EnumVariable('debug','Debug (default=0)', '0', allowed_values=('0','1')))
vars.Add(EnumVariable('asserts','Enable asserts (This flag is forced to 1 for debug=1) (default=0)', '0', allowed_values=('0','1')))
vars.Add(EnumVariable('arch','Target Architecture (default=armv7a)', 'armv7a', allowed_values=('armv7a','arm64-v8a','arm64-v8.2-a','x86_32','x86_64')))
vars.Add(EnumVariable('os','Target OS (default=linux)', 'linux', allowed_values=('linux','android','bare_metal')))
vars.Add(EnumVariable('build','Build type: (default=cross_compile)', 'cross_compile', allowed_values=('native','cross_compile')))
vars.Add(EnumVariable('Werror','Enable/disable the -Werror compilation flag (Default=1)', '1', allowed_values=('0','1')))
vars.Add(EnumVariable('opencl','Enable OpenCL support(Default=1)', '1', allowed_values=('0','1')))
vars.Add(EnumVariable('neon','Enable Neon support(Default=0)', '0', allowed_values=('0','1')))
vars.Add(EnumVariable('embed_kernels', 'Embed OpenCL kernels in library binary(Default=0)', '0', allowed_values=('0','1')))
vars.Add(BoolVariable('set_soname','Set the library\'s soname and shlibversion (Requires SCons 2.4 or above)', 0))
vars.Add(('extra_cxx_flags','Extra CXX flags to be appended to the build command', ''))

env = Environment(platform='posix', variables = vars, ENV = os.environ)

Help(vars.GenerateHelpText(env))

def version_at_least(version, required):
    end = min(len(version), len(required))

    for i in range(0, end, 2):
        if int(version[i]) < int(required[i]):
            return False
        elif int(version[i]) > int(required[i]):
            return True

    return True

if not GetOption("help"):
    flags = ['-D_GLIBCXX_USE_NANOSLEEP','-Wno-deprecated-declarations','-Wall','-DARCH_ARM',
             '-Wextra','-Wno-unused-parameter','-pedantic','-Wdisabled-optimization','-Wformat=2',
             '-Winit-self','-Wstrict-overflow=2','-Wswitch-default',
             '-fpermissive','-std=c++11','-Wno-vla','-Woverloaded-virtual',
             '-Wctor-dtor-privacy','-Wsign-promo','-Weffc++','-Wno-format-nonliteral','-Wno-overlength-strings','-Wno-strict-overflow']


    if env['neon'] == '1' and 'x86' in env['arch']:
            print "Cannot compile NEON for x86"
            Exit(1)

    if env['set_soname'] and not version_at_least( SCons.__version__, "2.4"):
        print "Setting the library's SONAME / SHLIBVERSION requires SCons 2.4 or above"
        print "Update your version of SCons or use set_soname=0"
        Exit(1)

    if os.environ.get('CXX','g++') == 'clang++':
        flags += ['-Wno-format-nonliteral','-Wno-deprecated-increment-bool','-Wno-vla-extension','-Wno-mismatched-tags']
    else:
        flags += ['-Wlogical-op','-Wnoexcept','-Wstrict-null-sentinel']

    files_to_delete = []

#Generate string with build options library version to embed in the library:
    git_hash="unknown"
    try:
        git_hash = subprocess.check_output(["git", "rev-parse","HEAD"])
    except OSError: # In case git is not present
        pass
    except subprocess.CalledProcessError:
        pass

    version_filename = "%s/arm_compute_version.embed" % os.path.dirname(Glob("src/core/*")[0].rstr())
    build_info = "\"arm_compute_version=%s Build options: %s Git hash=%s\"" % (VERSION, vars.args, git_hash.strip())
    open(version_filename,"w").write(build_info)
    files_to_delete.append( version_filename )

    def build_library(name, sources, libs, static=False):
        if static:
            obj = env.StaticLibrary(name, source = sources, LIBS=libs )
        else:
            if env['set_soname']:
                obj = env.SharedLibrary(name, source = sources, LIBS=libs, SHLIBVERSION=SONAME_VERSION)
                symlinks = []
                # Manually delete symlinks or SCons will get confused:
                directory = os.path.dirname( obj[0].path )
                library_prefix = obj[0].path[:-(1+len(SONAME_VERSION))]
                real_lib="%s.%s" % (library_prefix, SONAME_VERSION)
                for f in Glob( "#%s*" % library_prefix):
                    if str(f) != real_lib:
                        symlinks.append("%s/%s" % (directory,str(f)))
                clean = env.Command('clean-%s' % str(obj[0]), [], Delete(symlinks))
                Default(clean)
                Depends(obj, clean)
            else:
                obj = env.SharedLibrary(name, source = sources, LIBS=libs)

        Default(obj)
        return obj

    def resolve_includes(target, source, env):
        # File collection
        FileEntry = collections.namedtuple('FileEntry', 'target_name file_contents')

        # Include pattern
        pattern = re.compile("#include \"(.*)\"")

        # Get file contents
        files = []
        for s in source:
            name = s.rstr().split("/")[-1]
            contents = s.get_contents().splitlines()
            embed_target_name = s.abspath + "embed"
            entry = FileEntry(target_name=embed_target_name, file_contents=contents)
            files.append((name,entry))

        # Create dictionary of tupled list
        files_dict = dict(files)

        # Check for includes (can only be files in the same folder)
        final_files = []
        for file in files:
            done = False
            tmp_file = file[1].file_contents
            while not(done):
                file_count = 0
                updated_file = []
                for line in tmp_file:
                    found = pattern.search(line)
                    if found:
                        include_file = found.group(1)
                        data = files_dict[include_file].file_contents
                        updated_file.extend(data)
                    else:
                        updated_file.append(line)
                        file_count += 1

                # Check if all include are replaced.
                if file_count == len(tmp_file):
                    done = True

                # Update temp file
                tmp_file = updated_file

            # Append and prepend string literal identifiers and add expanded file to final list
            tmp_file.insert(0, "R\"(\n")
            tmp_file.append("\n)\"")
            entry = FileEntry(target_name=file[1].target_name, file_contents=tmp_file)
            final_files.append((file[0], entry))

        # Write output files
        for file in final_files:
            out_file = open(file[1].target_name, 'w+')
            contents = file[1].file_contents
            for line in contents:
                out_file.write("%s\n" % line)

    core_libs = []
    libs = []

    prefix=""

    if env['arch'] == 'armv7a':
        flags += ['-march=armv7-a','-mthumb','-mfpu=neon']

        if env['os'] in ['linux','bare_metal']:
            prefix = "arm-linux-gnueabihf-"
            flags += ['-mfloat-abi=hard']
        elif env['os'] == 'android':
            prefix = "arm-linux-androideabi-"
            flags += ['-mfloat-abi=softfp']
    elif env['arch'] == 'arm64-v8a':
        flags += ['-march=armv8-a']
        if env['os'] in ['linux','bare_metal']:
            prefix = "aarch64-linux-gnu-"
        elif env['os'] == 'android':
            prefix = "aarch64-linux-android-"
    elif env['arch'] == 'arm64-v8.2-a':
        flags += ['-march=armv8.2-a+fp16+simd']
        flags += ['-DARM_COMPUTE_ENABLE_FP16']
        if env['os'] in ['linux','bare_metal']:
            prefix = "aarch64-linux-gnu-"
        elif env['os'] == 'android':
            prefix = "aarch64-linux-android-"
    elif env['arch'] == 'x86_32':
        flags += ['-m32']
    elif env['arch'] == 'x86_64':
        flags += ['-m64']

    if env['build'] == 'native':
        prefix = ""

    env['CC'] = prefix + os.environ.get('CC','gcc')
    env['CXX'] = prefix + os.environ.get('CXX','g++')
    env['LD'] = prefix + "ld"
    env['AS'] = prefix + "as"
    env['AR'] = prefix + "ar"
    env['RANLIB'] = prefix + "ranlib"

    try:
        compiler_ver = subprocess.check_output( [env['CXX'] , "-dumpversion"] ).strip()
    except OSError:
        print "ERROR: Compiler '%s' not found" % env['CXX']
        Exit(1)

    if os.environ.get('CXX','g++') == 'g++':
        if env['arch'] == 'arm64-v8.2-a' and not version_at_least(compiler_ver, '6.2.1'):
            print "GCC 6.2.1 or newer is required to compile armv8.2-a code"
            Exit(1)

        if env['arch'] == 'arm64-v8a' and not version_at_least(compiler_ver, '4.9'):
            print "GCC 4.9 or newer is required to compile NEON code for AArch64"
            Exit(1)

        if version_at_least(compiler_ver, '6.1'):
            flags += ['-Wno-ignored-attributes']

        if compiler_ver == '4.8.3':
            flags += ['-Wno-array-bounds']

    if env['Werror'] == '1':
        flags += ['-Werror']

    example_libs = []
    if env['os'] == 'android':
        flags += ['-DANDROID']
        env.Append(LINKFLAGS=['-pie','-static-libstdc++'])
        example_libs = ['arm_compute-static']
    elif env['os'] == 'bare_metal':
        env.Append(LINKFLAGS=['-static'])
        flags += ['-fPIC','-DNO_MULTI_THREADING']
        example_libs = ['arm_compute-static']
    else:
        libs += ['pthread']
        example_libs = ['arm_compute']

    if env['opencl'] == '1':
        if env['os'] == 'bare_metal':
            raise Exception("Cannot link OpenCL statically, which is required on bare metal")
        core_libs += ['OpenCL']
        if env['embed_kernels'] == '1':
            flags += ['-DEMBEDDED_KERNELS']

    if env['debug'] == '1':
        env['asserts'] = '1'
        flags += ['-O0','-g','-gdwarf-2']
    else:
        flags += ['-O3','-ftree-vectorize']

    if env['asserts'] == '1':
        flags += ['-DARM_COMPUTE_ASSERTS_ENABLED']

    env.Append(CPPPATH=['.','#include'])
    env.Append(LIBPATH=['#build','.'])
    env.Append(CXXFLAGS=flags)
    env.Append(CXXFLAGS=env['extra_cxx_flags'])

    core_files = Glob('src/core/*.cpp')
    core_files += Glob('src/core/CPP/*.cpp')

    files = Glob('src/runtime/*.cpp')

    embed_files = []
    core_files += Glob('src/core/CPP/kernels/*.cpp')

    files += Glob('src/runtime/CPP/*.cpp')

    if env['opencl'] == '1':
        example_libs += ['OpenCL']
        core_files += Glob('src/core/CL/*.cpp')
        core_files += Glob('src/core/CL/kernels/*.cpp')
        files += Glob('src/runtime/CL/*.cpp')
        files += Glob('src/runtime/CL/functions/*.cpp')
        # Generate embed files
        if env['embed_kernels'] == '1':
            cl_files  = Glob('src/core/CL/cl_kernels/*.cl') + Glob('src/core/CL/cl_kernels/*.h')
            source_list = []
            for file in cl_files:
                source_name = file.rstr()
                source_list.append(source_name)
                embed_files.append(source_name + "embed")
            generate_embed = env.Command(embed_files, source_list, action=resolve_includes)
            Default(generate_embed)
            files_to_delete += embed_files

    if env['neon'] == '1':
        core_files += Glob('src/core/NEON/*.cpp')
        core_files += Glob('src/core/NEON/kernels/*.cpp')
        files += Glob('src/runtime/NEON/*.cpp')
        files += Glob('src/runtime/NEON/functions/*.cpp')

    objects=[]
    static_core_objects = [ env.StaticObject( f ) for f in core_files ]
    shared_core_objects = [ env.SharedObject( f ) for f in core_files ]

    arm_compute_core_a = build_library('arm_compute_core-static', static_core_objects, core_libs, static=True)
    objects.append(arm_compute_core_a)
    Export('arm_compute_core_a')

    if env['os'] != 'bare_metal':
        arm_compute_core_so = build_library('arm_compute_core', shared_core_objects, core_libs, static=False)
        objects.append(arm_compute_core_so)
        Export('arm_compute_core_so')
    shared_objects = [ env.SharedObject( f ) for f in files ]
    static_objects = [ env.StaticObject( f ) for f in files ]

    arm_compute_a = build_library('arm_compute-static', static_core_objects + static_objects, libs, static=True)
    objects.append(arm_compute_a)
    Export('arm_compute_a')
    if env['os'] != 'bare_metal':
        arm_compute_so = build_library('arm_compute', shared_core_objects + shared_objects, libs, static=False)
        objects.append(arm_compute_so)
        Export('arm_compute_so')

# Delete produced embed files
    clean_embed = env.Command('clean-embed', [], Delete(files_to_delete))
    Default(clean_embed)
    env.Depends(clean_embed, objects)
    alias = env.Alias("arm_compute",objects)
    Default(alias)

# Build examples
    test_helpers = env.Object("test_helpers/Utils.cpp")

    if env['opencl'] == '1' and env['neon'] == '1':
        for file in Glob("examples/neoncl_*.cpp"):
            example =  os.path.basename( os.path.splitext(str(file))[0])
            prog = env.Program(example, ['examples/%s.cpp' % example, test_helpers], LIBS=example_libs)
            alias = env.Alias(example, prog)
            Depends(prog, objects)
            Default( alias )

    if env['opencl'] == '1':
        for file in Glob("examples/cl_*.cpp"):
            example =  os.path.basename( os.path.splitext(str(file))[0])
            prog = env.Program(example, ['examples/%s.cpp' % example, test_helpers], LIBS=example_libs)
            alias = env.Alias(example, prog)
            Depends(prog, objects)
            Default( alias )

    if env['neon'] == '1':
        for file in Glob("examples/neon_*.cpp"):
            example =  os.path.basename( os.path.splitext(str(file))[0])
            prog = env.Program(example, ['examples/%s.cpp' % example, test_helpers], LIBS=example_libs)
            alias = env.Alias(example, prog)
            Depends(prog, objects)
            Default( alias )