#include <compiler.h>

fn void compile(Arena* arena, Options options)
{
    auto base_allocation_type_count = i128_offset + // 64 * 2 for basic integer types
        2 + // u128, s128
        2; // void, noreturn
    auto base_type_allocation = arena_allocate<Type>(arena, base_allocation_type_count);

    auto* type_it = base_type_allocation.pointer;

    bool signs[] = {false, true};
    Type* previous = 0;

    for (bool sign: signs)
    {
        for (u32 bit_index = 0; bit_index < 64; bit_index += 1)
        {
            auto bit_count = bit_index + 1;
            auto first_digit = (u8)(bit_count < 10 ? bit_count % 10 + '0' : bit_count / 10 + '0');
            auto second_digit = (u8)(bit_count > 9 ? bit_count % 10 + '0' : 0);
            u8 name_buffer[] = { u8(sign ? 's' : 'u'), first_digit, second_digit };
            u64 name_length = 2 + (bit_count > 9);
            auto name_stack = String{name_buffer, name_length};

            auto name = arena_duplicate_string(arena, name_stack);

            *type_it = {
                .integer = {
                    .bit_count = bit_count,
                    .is_signed = sign,
                },
                .id = TypeId::integer,
                .name = name,
            };
            if (previous) previous->next = type_it;
            previous = type_it;
            type_it += 1;
        }
    }

    for (bool sign: signs)
    {
        auto name = sign ? string_literal("s128") : string_literal("u128");
        *type_it = {
            .integer = {
                .bit_count = 128,
                .is_signed = sign,
            },
            .id = TypeId::integer,
            .name = name,
            .next = previous,
        };
        if (previous) previous->next = type_it;
        previous = type_it;
        type_it += 1;
    }

    auto void_type = type_it;
    type_it += 1;
    auto noreturn_type = type_it;
    type_it += 1;
    assert((u64)(type_it - base_type_allocation.pointer) == base_allocation_type_count);

    previous->next = void_type;
    *void_type = {
        .id = TypeId::void_type,
        .name = string_literal("void"),
        .next = noreturn_type,
    };
    *noreturn_type = {
        .id = TypeId::noreturn,
        .name = string_literal("noreturn"),
    };

    auto module = Module{
        .arena = arena,
        .content = options.content,
        .first_type = base_type_allocation.pointer,
        .last_type = noreturn_type,
        .scope = {
            .kind = ScopeKind::global,
        },
        .name = options.name,
        .path = options.path,
        .executable = options.executable,
        .objects = options.objects,
        .target = options.target,
        .build_mode = options.build_mode,
        .has_debug_info = options.has_debug_info,
        .silent = options.silent,
    };
    module.void_value = new_value(&module);
    *module.void_value = {
        .type = void_type,
        .id = ValueId::infer_or_ignore,
    };

    parse(&module);
    emit(&module);
}

fn void compile_file(Arena* arena, Compile options)
{
    auto relative_file_path = options.relative_file_path;
    if (relative_file_path.length < 5)
    {
        fail();
    }

    auto extension_start = string_last_character(relative_file_path, '.');
    if (extension_start == string_no_match)
    {
        fail();
    }

    if (!relative_file_path(extension_start).equal(string_literal(".bbb")))
    {
        fail();
    }

    auto separator_index = string_last_character(relative_file_path, '/');
    separator_index = separator_index == string_no_match ? 0 : separator_index;

    auto base_start = separator_index + (separator_index != 0 || relative_file_path[separator_index] == '/');
    auto base_name = relative_file_path(base_start, extension_start);

    auto is_compiler = relative_file_path.equal(string_literal("src/compiler.bbb"));

    String output_path_dir_parts[] = {
        string_literal(base_cache_dir),
        is_compiler ? string_literal("/compiler") : string_literal("/"),
        build_mode_to_string(options.build_mode),
        string_literal("_"),
        options.has_debug_info ? string_literal("di") : string_literal("nodi"),
    };
    auto output_path_dir = arena_join_string(arena, array_to_slice(output_path_dir_parts));

    make_directory(base_cache_dir);

    if (is_compiler)
    {
        make_directory(base_cache_dir "/compiler");
    }

    make_directory(cstr(output_path_dir));
    
    String output_path_base_parts[] = {
        output_path_dir,
        string_literal("/"),
        base_name,
    };
    auto output_path_base = arena_join_string(arena, array_to_slice(output_path_base_parts));
    String output_object_path_parts[] = {
        output_path_base,
        string_literal(".o"),
    };
    auto output_object_path = arena_join_string(arena, array_to_slice(output_object_path_parts));
    auto output_executable_path = output_path_base;

    auto file_content = file_read(arena, relative_file_path);
    auto file_path = path_absolute(arena, relative_file_path);
    auto c_abi_object_path = string_literal("build/c_abi.o");

    String objects[] = {
        c_abi_object_path,
        output_object_path,
    };
    Slice<String> object_slice = array_to_slice(objects);
    object_slice = object_slice(!base_name.equal(string_literal("c_abi")));

    compile(arena, {
            .content = file_content,
            .path = file_path,
            .executable = output_executable_path,
            .name = base_name,
            .objects = object_slice,
            .target = {
            .cpu = CPUArchitecture::x86_64,
            .os = OperatingSystem::linux_,
            },
            .build_mode = options.build_mode,
            .has_debug_info = options.has_debug_info,
            .silent = options.silent,
            });
}

global_variable String names[] = {
    string_literal("minimal"),
    string_literal("comments"),
    string_literal("constant_add"),
    string_literal("constant_and"),
    string_literal("constant_div"),
    string_literal("constant_mul"),
    string_literal("constant_rem"),
    string_literal("constant_or"),
    string_literal("constant_sub"),
    string_literal("constant_xor"),
    string_literal("constant_shift_left"),
    string_literal("constant_shift_right"),
    string_literal("minimal_stack"),
    string_literal("minimal_stack_arithmetic"),
    string_literal("minimal_stack_arithmetic2"),
    string_literal("minimal_stack_arithmetic3"),
    string_literal("stack_negation"),
    string_literal("stack_add"),
    string_literal("stack_sub"),
    string_literal("extend"),
    string_literal("integer_max"),
    string_literal("integer_hex"),
    string_literal("basic_pointer"),
    string_literal("basic_call"),
    string_literal("basic_branch"),
    string_literal("basic_array"),
    string_literal("basic_enum"),
    string_literal("basic_slice"),
    string_literal("basic_string"),
    string_literal("basic_varargs"),
    string_literal("basic_while"),
    string_literal("pointer"),
    string_literal("pointer_cast"),
    string_literal("u1_return"),
    string_literal("local_type_inference"),
    string_literal("global"),
    string_literal("function_pointer"),
    string_literal("extern"),
    string_literal("byte_size"),
    string_literal("argv"),
    string_literal("assignment_operators"),
    string_literal("not_pointer"),
    string_literal("bits"),
    string_literal("bits_no_backing_type"),
    string_literal("bits_return_u1"),
    string_literal("bits_zero"),
    string_literal("comparison"),
    string_literal("global_struct"),
    string_literal("if_no_else"),
    string_literal("if_no_else_void"),
    string_literal("indirect"),
    string_literal("indirect_struct"),
    string_literal("indirect_varargs"),
    string_literal("ret_c_bool"),
    string_literal("return_type_builtin"),
    string_literal("return_u64_u64"),
    string_literal("select"),
    string_literal("slice"),
    string_literal("small_struct_ints"),
    string_literal("struct_assignment"),
    string_literal("struct"),
    string_literal("struct_u64_u64"),
    string_literal("struct_varargs"),
    string_literal("struct_zero"),
    string_literal("unreachable"),
    string_literal("varargs"),
    string_literal("c_abi0"),
    string_literal("c_abi1"),
    string_literal("c_med_struct_ints"),
    string_literal("c_ret_struct_array"),
    string_literal("c_split_struct_ints"),
    string_literal("c_string_to_slice"),
    string_literal("c_struct_with_array"),
    string_literal("c_function_pointer"),
    string_literal("basic_bool_call"),
    string_literal("c_abi"),
    string_literal("string_to_enum"),
    string_literal("abi_enum_bool"),
    string_literal("empty_if"),
    string_literal("else_if"),
    string_literal("else_if_complicated"),
    string_literal("basic_shortcircuiting_if"),
    string_literal("shortcircuiting_if"),
    string_literal("field_access_left_assign"),
    string_literal("for_each"),
    string_literal("pointer_decay"),
    string_literal("enum_name"),
    string_literal("slice_of_slices"),
    string_literal("type_alias"),
    string_literal("integer_formats"),
    string_literal("return_small_struct"),
    string_literal("for_each_int"),
    string_literal("bool_array"),
    string_literal("basic_union"),
    string_literal("break_continue"),
    string_literal("constant_global_reference"),
    string_literal("self_referential_struct"),
    string_literal("forward_declared_type"),
    string_literal("basic_macro"),
    string_literal("generic_macro"),
    string_literal("generic_pointer_macro"),
    string_literal("noreturn_macro"),
    string_literal("generic_pointer_array"),
};

void entry_point(Slice<const char*> arguments, Slice<const char*> environment)
{
    unused(environment);
    Arena* arena = arena_initialize_default(8 * mb);

    if (arguments.length < 2)
    {
        fail_with_message(string_literal("error: Not enough arguments\n"));
    }

    String command_string = c_string_to_slice(arguments[1]);
    String command_strings[] = {
        string_literal("compile"),
        string_literal("test"),
    };
    static_assert(array_length(command_strings) == (u64)Command::count);

    backing_type(Command) i;
    for (i = 0; i < (backing_type(Command))Command::count; i += 1)
    {
        String candidate = command_strings[i];
        if (candidate.equal(command_string))
        {
            break;
        }
    }

    auto command = (Command)i;

    switch (command)
    {
    case Command::compile:
        {
            if (arguments.length < 3)
            {
                fail_with_message(string_literal("Not enough arguments for command 'compile'\n"));
            }

            auto build_mode = BuildMode::debug_none;
            auto has_debug_info = true;

            if (arguments.length >= 4)
            {
                auto build_mode_string = c_string_to_slice(arguments[3]);
                String build_mode_strings[] = {
                    string_literal("debug_none"),
                    string_literal("debug"),
                    string_literal("soft_optimize"),
                    string_literal("optimize_for_speed"),
                    string_literal("optimize_for_size"),
                    string_literal("aggressively_optimize_for_speed"),
                    string_literal("aggressively_optimize_for_size"),
                };

                backing_type(BuildMode) i;
                for (i = 0; i < (backing_type(BuildMode))BuildMode::count; i += 1)
                {
                    String candidate = build_mode_strings[i];
                    if (build_mode_string.equal(candidate))
                    {
                        break;
                    }
                }

                build_mode = (BuildMode)i;
                if (build_mode == BuildMode::count)
                {
                    fail_with_message(string_literal("Invalid build mode\n"));
                }
            }

            if (arguments.length >= 5)
            {
                auto has_debug_info_string = c_string_to_slice(arguments[3]);
                if (has_debug_info_string.equal(string_literal("true")))
                {
                    has_debug_info = true;
                }
                else if (has_debug_info_string.equal(string_literal("false")))
                {
                    has_debug_info = false;
                }
                else
                {
                    fail_with_message(string_literal("Wrong value for has_debug_info\n"));
                }
            }

            auto relative_file_path = c_string_to_slice(arguments[2]);

            compile_file(arena, {
                .relative_file_path = relative_file_path,
                .build_mode = build_mode,
                .has_debug_info = has_debug_info,
                .silent = false,
            });
        } break;
    case Command::test:
        {
            // TODO: provide more arguments
            if (arguments.length != 2)
            {
                fail_with_message(string_literal("error: 'test' command takes no arguments"));
            }

            // TODO: introduce build mode, debug info switch, etc

            for (auto name: names)
            {
                auto position = arena->position;

                String relative_file_path_parts[] = { string_literal("tests/"), name, string_literal(".bbb") };
                auto relative_file_path = arena_join_string(arena, array_to_slice(relative_file_path_parts));
                auto build_mode = BuildMode::debug_none; 
                bool has_debug_info = true;
                compile_file(arena, {
                        .relative_file_path = relative_file_path,
                        .build_mode = build_mode,
                        .has_debug_info = has_debug_info,
                        .silent = true,
                });

                // TODO: introduce test

                arena_restore(arena, position);
            }
        } break;
    case Command::count:
        {
            fail_with_message(string_literal("error: Invalid command\n"));
        } break;
    }
}