# -*- python -*-

from pathlib import Path
from dataclasses import dataclass

#
# File lists
#

PROGRAM_SOURCES = ["src/main.c"]
LIB_SRCS = [
    "src/arena.c",
    "src/builtins.c",
    "src/evaluate.c",
    "src/memory.c",
    "src/special.c",
    "src/scope.c",
    "src/utility.c",
    "src/parse.c",
]
LIB_INCLUDES = ["src/"]


TEST_SRCS = [
    "test/test_arena.c",
    "test/test_e2e.c",
    "test/test_parse.c",
    "test/test_scope.c",
    "test/test_utility.c",
]
TEST_LIB_SRCS = ["third-party/unity/src/unity.c"]
TEST_LIB_INCLUDES = ["third-party/unity/src/"]


def with_suffix(path, suffix):
    return str(Path(path).with_suffix(suffix))


@dataclass
class BuildVariant:
    variant_name: str
    cc: str
    ccflags: list[str]
    libs: list[str]
    linkflags: list[str]
    enable_compile_commands_db: bool = False

    def built(self, path):
        return self.variant_dir + path

    def enable_compile_commands(self):
        self.env.Tool("compilation_db")
        self.env.CompilationDatabase()

    def configure_lib(self):
        self.lib_objs = [
            self.env.Object(target=self.built(with_suffix(p, ".o")), source=p)
            for p in LIB_SRCS
        ]
        self.static_lib = self.env.StaticLibrary(self.built("uclisp"), self.lib_objs)

    def configure_repl(self):
        pgm_objs = [
            self.env.Object(target=self.built(with_suffix(p, ".o")), source=p)
            for p in PROGRAM_SOURCES
        ]
        repl_env = self.env.Clone()
        repl_env.Append(LIBS=[self.static_lib])
        self.repl_program = repl_env.Program(
            self.built("uclisp"), pgm_objs,
        )

    def configure_tests(self):
        test_lib_objs = [
            self.test_env.Object(target=self.built(with_suffix(p, ".o")), source=p)
            for p in TEST_LIB_SRCS
        ]

        self.test_env.Append(LIBS=[self.static_lib])

        test_deps = test_lib_objs
        test_objs = [
            self.test_env.Object(target=self.built(with_suffix(p, ".o")), source=p)
            for p in TEST_SRCS
        ]

        self.tests = [
            self.test_env.Program(
                self.built(with_suffix(p, "")),
                test_deps + [self.built(with_suffix(p, ".o"))],
            )
            for p in TEST_SRCS
        ]

    def configure(self):
        self.variant_dir = f"build/{self.variant_name}/"

        #
        # Construct Environments
        #

        self.env = Environment(
            CC=self.cc,
            CPPPATH=LIB_INCLUDES,
            COMPILATIONDB_USE_ABSPATH=True,
            CCFLAGS=self.ccflags,
            LINKFLAGS=self.linkflags,
            LIBS=self.libs,
        )

        if self.enable_compile_commands_db:
            self.enable_compile_commands()

        self.test_env = self.env.Clone()
        self.test_env.Append(CPPPATH=TEST_LIB_INCLUDES)

        self.configure_lib()
        self.configure_repl()
        self.configure_tests()

        self.env.Substfile(
            target=self.built("run_tests.sh"),
            source="run_tests.sh.in",
            SUBST_DICT={
                "@tests@": " ".join(
                    str(Path(str(test[0])).resolve()) for test in self.tests
                )
            },
        )

        self.env.Command(
            self.built("run_tests"),
            self.built("run_tests.sh"),
            Chmod(self.built("run_tests.sh"), 0o755),
        )

        # Copy default build compile commands to root, which is where tools seem to want
        # it.
        if self.enable_compile_commands_db:
            Copy("compile_commands.json", self.built("compile_commands.json"))

        self.env.Alias(self.variant_name, self.variant_dir)


base_ccflags = ["-Werror", "-Wall", "-Wextra", "-Wno-unused-parameter"]
debug_ccflags = ["-ggdb", "-O0"]
release_ccflags = [
    "-Oz",
    "-flto",
    "-ffunction-sections",
    "-fdata-sections",
    "-Wl,--gc-sections",
]

variants = [
    BuildVariant(
        variant_name="debug",
        cc="gcc",
        ccflags=debug_ccflags + base_ccflags,
        libs=["readline"],
        linkflags=[],
        enable_compile_commands_db=True,
    ),
    BuildVariant(
        variant_name="release",
        cc="gcc",
        ccflags=release_ccflags + base_ccflags,
        linkflags=[],
        libs=["readline"],
    ),
    BuildVariant(
        variant_name="arm-debug",
        cc="arm-none-eabi-gcc",
        ccflags=["-DNO_READLINE"] + debug_ccflags + base_ccflags,
        libs=[],
        linkflags=["--specs=nosys.specs"],
    ),
]

for variant in variants:
    variant.configure()