import os
import sys
import subprocess

arguments = sys.argv[2]
vdso_usr  = arguments
vdso_path = os.path.join(vdso_usr, '..', '..', '..')

EXEC_PATH = os.getenv('RTT_EXEC_PATH') or '/usr/bin'
PREFIX    = os.getenv('RTT_CC_PREFIX') or 'riscv64-none-elf-'

def get_riscv64_default_arch_abi(gcc_bin):
    try:
        result = subprocess.check_output(
            [gcc_bin, '-Q', '--help=target'],
            universal_newlines=True
        )
        arch = None
        abi = None
        for line in result.splitlines():
            if '-march=' in line:
                arch = line.strip().split()[1]
                arch = arch.split('_')[0]  # Get the base architecture, e.g., rv64imafdc
            if '-mabi=' in line and 'option' not in line:
                abi = line.strip().split()[1]
        return arch, abi
    except Exception as e:
        print("Error getting arch/abi:", e)
        return None, None

# get the gcc path
CC_BIN = PREFIX + 'gcc'
arch, abi = get_riscv64_default_arch_abi(CC_BIN)
if arch and abi:
    DEVICE = f' -march={arch} -mabi={abi} '
else:
    DEVICE = ' -march=rv64imafdc -mabi=lp64'  # fallback

CC      = PREFIX + 'gcc'
CPP     = PREFIX + 'cpp'
AS      = PREFIX + 'gcc'
AR      = PREFIX + 'ar'
LINK    = PREFIX + 'gcc'

AFLAGS  = ' -x assembler-with-cpp'
CFLAGS  = DEVICE + ' -Wall -Wno-cpp -std=gnu99 -fdiagnostics-color=always -fPIC -O2'
LFLAGS  = DEVICE + ' -Bsymbolic -Wl,--gc-sections -T {path}/vdso.lds'.format(path=vdso_usr)
CFLAGS += " -I . -I {vdso_path} ".format(vdso_path=vdso_path)

src = Glob('*.c')
env = Environment(tools=['gcc', 'link'],
    AS   = AS,   ASFLAGS = AFLAGS,
    CC   = CC,   CFLAGS  = CFLAGS,
    CPP  = CPP,  AR      = AR,
    LINK = LINK, LINKFLAGS = LFLAGS)
env.PrependENVPath('PATH', EXEC_PATH)

target = os.path.join(vdso_path, 'user', 'build', 'libvdso.so')
shared_lib = env.SharedLibrary(target=target, source=src)
Clean(shared_lib, '{vdso_usr}/vdso.lds'.format(vdso_usr=vdso_usr))
Clean(shared_lib, '.sconsign.dblite')
env.Default(shared_lib)