//! This module defines the different ffi_abi values for each platform.
//!
//! This module is set-up to define all the constants for each platform, but only export those which
//! are actually relevant to the target arch. This is done as a compile check to ensure the code
//! paths in less utilized architectures largely continue to compile.

#![allow(unused)]

/// From libffi:src/x86/ffitarget.h
/// See: https://github.com/libffi/libffi/blob/369ef49f71186fc9d6ab15614488ad466fac3fc1/src/x86/ffitarget.h#L80
mod x86 {
    pub mod x86_win64 {
        use crate::ffi_abi;

        pub const ffi_abi_FFI_FIRST_ABI: ffi_abi = 0;
        pub const ffi_abi_FFI_WIN64: ffi_abi = 1;
        pub const ffi_abi_FFI_GNUW64: ffi_abi = 2;
        pub const ffi_abi_FFI_LAST_ABI: ffi_abi = 3;

        mod gnu {
            pub const ffi_abi_FFI_DEFAULT_ABI: crate::ffi_abi = super::ffi_abi_FFI_GNUW64;
        }

        mod msvc {
            pub const ffi_abi_FFI_DEFAULT_ABI: crate::ffi_abi = super::ffi_abi_FFI_GNUW64;
        }

        #[cfg(target_env = "gnu")]
        pub use gnu::*;
        #[cfg(target_env = "msvc")]
        pub use msvc::*;

        // See: https://github.com/libffi/libffi/blob/369ef49f71186fc9d6ab15614488ad466fac3fc1/src/x86/ffitarget.h#L137
        pub const FFI_TRAMPOLINE_SIZE: usize = 24;
        pub const FFI_NATIVE_RAW_API: u32 = 0;
    }

    pub mod x86_64 {
        use crate::ffi_abi;

        pub const ffi_abi_FFI_FIRST_ABI: ffi_abi = 1;
        pub const ffi_abi_FFI_UNIX64: ffi_abi = 2;
        pub const ffi_abi_FFI_WIN64: ffi_abi = 3;
        pub const ffi_abi_FFI_EFI64: ffi_abi = ffi_abi_FFI_WIN64;
        pub const ffi_abi_FFI_GNUW64: ffi_abi = 4;
        pub const ffi_abi_FFI_LAST_ABI: ffi_abi = 5;
        pub const ffi_abi_FFI_DEFAULT_ABI: ffi_abi = ffi_abi_FFI_UNIX64;

        // See: https://github.com/libffi/libffi/blob/369ef49f71186fc9d6ab15614488ad466fac3fc1/src/x86/ffitarget.h#L137
        pub const FFI_TRAMPOLINE_SIZE: usize = 24;
        pub const FFI_NATIVE_RAW_API: u32 = 0;
    }

    pub mod x86_win32 {
        use crate::ffi_abi;

        pub const ffi_abi_FFI_FIRST_ABI: ffi_abi = 0;
        pub const ffi_abi_FFI_SYSV: ffi_abi = 1;
        pub const ffi_abi_FFI_STDCALL: ffi_abi = 2;
        pub const ffi_abi_FFI_THISCALL: ffi_abi = 3;
        pub const ffi_abi_FFI_FASTCALL: ffi_abi = 4;
        pub const ffi_abi_FFI_MS_CDECL: ffi_abi = 5;
        pub const ffi_abi_FFI_PASCAL: ffi_abi = 6;
        pub const ffi_abi_FFI_REGISTER: ffi_abi = 7;
        pub const ffi_abi_FFI_LAST_ABI: ffi_abi = 8;
        pub const ffi_abi_FFI_DEFAULT_ABI: ffi_abi = ffi_abi_FFI_MS_CDECL;

        // See: https://github.com/libffi/libffi/blob/369ef49f71186fc9d6ab15614488ad466fac3fc1/src/x86/ffitarget.h#L137
        pub const FFI_TRAMPOLINE_SIZE: usize = 12;
        pub const FFI_NATIVE_RAW_API: u32 = 1;
    }

    pub mod x86 {
        use crate::ffi_abi;

        pub const ffi_abi_FFI_FIRST_ABI: ffi_abi = 0;
        pub const ffi_abi_FFI_SYSV: ffi_abi = 1;
        pub const ffi_abi_FFI_THISCALL: ffi_abi = 3;
        pub const ffi_abi_FFI_FASTCALL: ffi_abi = 4;
        pub const ffi_abi_FFI_STDCALL: ffi_abi = 5;
        pub const ffi_abi_FFI_PASCAL: ffi_abi = 6;
        pub const ffi_abi_FFI_REGISTER: ffi_abi = 7;
        pub const ffi_abi_FFI_MS_CDECL: ffi_abi = 8;
        pub const ffi_abi_FFI_LAST_ABI: ffi_abi = 9;
        pub const ffi_abi_FFI_DEFAULT_ABI: ffi_abi = ffi_abi_FFI_SYSV;

        // See: https://github.com/libffi/libffi/blob/369ef49f71186fc9d6ab15614488ad466fac3fc1/src/x86/ffitarget.h#L137
        pub const FFI_TRAMPOLINE_SIZE: usize = 12;
        pub const FFI_NATIVE_RAW_API: u32 = 1;
    }

    pub const FFI_GO_CLOSURES: u32 = 1;
}

#[cfg(all(target_arch = "x86_64", windows))]
pub use x86::x86_win64::*;

#[cfg(all(target_arch = "x86_64", unix))]
pub use x86::x86_64::*;

#[cfg(all(target_arch = "x86", windows))]
pub use x86::x86_win32::*;

#[cfg(all(target_arch = "x86", unix))]
pub use x86::x86::*;

/// From libffi:src/arm/ffitarget.h
/// See: https://github.com/libffi/libffi/blob/db5706ff285c476aa3c0f811ff2b188319ac3ebe/src/arm/ffitarget.h
mod arm {
    use crate::ffi_abi;

    pub const ffi_abi_FFI_FIRST_ABI: ffi_abi = 0;
    pub const ffi_abi_FFI_SYSV: ffi_abi = 1;
    pub const ffi_abi_FFI_VFP: ffi_abi = 2;
    pub const ffi_abi_FFI_LAST_ABI: ffi_abi = 3;
    pub const ffi_abi_FFI_DEFAULT_ABI: ffi_abi = ffi_abi_FFI_SYSV;

    // See: https://github.com/libffi/libffi/blob/db5706ff285c476aa3c0f811ff2b188319ac3ebe/src/arm/ffitarget.h#L84
    pub const FFI_GO_CLOSURES: u32 = 1;
    pub const FFI_TRAMPOLINE_SIZE: usize = 12;
    pub const FFI_NATIVE_RAW_API: u32 = 0;
}

#[cfg(target_arch = "arm")]
pub use arm::*;

/// From libffi:src/aarch64/ffitarget.h
/// See: https://github.com/libffi/libffi/blob/c2a6859012d928b67a83619bd5087674a96b9254/src/aarch64/ffitarget.h#L44
mod aarch64 {
    use crate::ffi_abi;

    pub const ffi_abi_FFI_FIRST_ABI: ffi_abi = 0;
    pub const ffi_abi_FFI_SYSV: ffi_abi = 1;
    pub const ffi_abi_FFI_LAST_ABI: ffi_abi = 2;
    pub const ffi_abi_FFI_DEFAULT_ABI: ffi_abi = ffi_abi_FFI_SYSV;

    pub const FFI_NATIVE_RAW_API: u32 = 0;

    #[cfg(target_vendor = "apple")]
    pub const FFI_TRAMPOLINE_SIZE: usize = 16;

    #[cfg(not(target_vendor = "apple"))]
    pub const FFI_TRAMPOLINE_SIZE: usize = 24;

    // No GO_CLOSURES on iOS or Windows
    #[cfg(not(any(target_os = "windows", target_vendor = "apple")))]
    pub const FFI_GO_CLOSURES: u32 = 1;
}

#[cfg(target_arch = "aarch64")]
pub use aarch64::*;

/// From libffi:src/powerpc/ffitarget.h
/// See: https://github.com/libffi/libffi/blob/73dd43afc8a447ba98ea02e9aad4c6898dc77fb0/src/powerpc/ffitarget.h#L60
mod powerpc {
    pub mod powerpc {
        use crate::ffi_abi;

        pub const ffi_abi_FFI_FIRST_ABI: ffi_abi = 0;
        pub const ffi_abi_FFI_SYSV_SOFT_FLOAT: ffi_abi = 0b000001;
        pub const ffi_abi_FFI_SYSV_STRUCT_RET: ffi_abi = 0b000010;
        pub const ffi_abi_FFI_SYSV_IBM_LONG_DOUBLE: ffi_abi = 0b000100;
        pub const ffi_abi_FFI_SYSV: ffi_abi = 0b001000;
        pub const ffi_abi_FFI_SYSV_LONG_DOUBLE_128: ffi_abi = 0b010000;

        mod fprs {
            pub const SOFT_FLOAT_FLAG: crate::ffi_abi = 0b0;
        }

        mod no_fprs {
            pub const SOFT_FLOAT_FLAG: crate::ffi_abi = super::ffi_abi_FFI_SYSV_SOFT_FLOAT;
        }

        #[cfg(target_env = "gnuspe")]
        use no_fprs::*;

        #[cfg(not(target_feature = "gnuspe"))]
        use fprs::*;

        mod struct_ret {
            pub const STRUCT_RET_FLAG: crate::ffi_abi = super::ffi_abi_FFI_SYSV_STRUCT_RET;
        }

        mod no_struct_ret {
            pub const STRUCT_RET_FLAG: crate::ffi_abi = 0b0;
        }

        #[cfg(target_os = "netbsd")]
        use struct_ret::*;

        #[cfg(not(target_os = "netbsd"))]
        use no_struct_ret::*;

        mod long_double_64 {
            pub const LONG_DOUBLE_128_FLAG: crate::ffi_abi = 0b0;
        }

        mod long_double_128 {
            pub const LONG_DOUBLE_128_FLAG: crate::ffi_abi =
                super::ffi_abi_FFI_SYSV_LONG_DOUBLE_128;
        }

        // IEEE128 is not supported on BSD or when targeting musl:
        // https://github.com/rust-lang/llvm-project/blob/cb7f903994646c5b9223e0bb6cee3792190991f7/clang/lib/Basic/Targets/PPC.h#L379

        #[cfg(any(target_os = "netbsd", target_os = "freebsd", target_env = "musl"))]
        use long_double_64::*;

        #[cfg(not(any(target_os = "netbsd", target_os = "freebsd", target_env = "musl")))]
        use long_double_128::*;

        pub const ffi_abi_FFI_DEFAULT_ABI: ffi_abi = ffi_abi_FFI_SYSV
            | ffi_abi_FFI_SYSV_IBM_LONG_DOUBLE
            | SOFT_FLOAT_FLAG
            | STRUCT_RET_FLAG
            | LONG_DOUBLE_128_FLAG;

        pub const FFI_TRAMPOLINE_SIZE: usize = 40;
        pub const FFI_NATIVE_RAW_API: u32 = 0;
        pub const FFI_GO_CLOSURES: u32 = 1;
    }

    pub mod powerpc64 {
        use crate::ffi_abi;

        pub const ffi_abi_FFI_FIRST_ABI: ffi_abi = 0;
        pub const ffi_abi_FFI_LINUX_STRUCT_ALIGN: ffi_abi = 0b000001;
        pub const ffi_abi_FFI_LINUX_LONG_DOUBLE_128: ffi_abi = 0b000010;
        pub const ffi_abi_FFI_LINUX_LONG_DOUBLE_IEEE128: ffi_abi = 0b000100;
        pub const ffi_abi_FFI_LINUX: ffi_abi = 0b001000;

        mod elfv1 {
            pub const STRUCT_ALIGN_FLAG: crate::ffi_abi = 0b0;
            pub const FFI_TRAMPOLINE_SIZE: usize = 24;
        }

        mod elfv2 {
            pub const STRUCT_ALIGN_FLAG: crate::ffi_abi = super::ffi_abi_FFI_LINUX_STRUCT_ALIGN;
            pub const FFI_TRAMPOLINE_SIZE: usize = 32;
        }

        // I think this should be something like `target_abi = "elf_v2"`, but that's not yet
        // supported.
        // Discussion: https://github.com/rust-lang/rust/issues/60617
        // RFC: https://github.com/rust-lang/rfcs/pull/2992
        //
        // Instead, this is based on the current defaults at the time of this writing:
        // https://github.com/rust-lang/rust/blob/50d2c3abd59af8cbed7e001b5b4e2f6a9a011112/src/librustc_target/abi/call/powerpc64.rs#L122

        #[cfg(any(
            // ELFv1 is the used for powerpc64 when not targeting musl
            all(target_arch = "powerpc64", target_endian="big", not(target_env = "musl")),
            // Use empty flags when targeting a non-PowerPC target, too, just so code compiles.
            not(all(target_arch = "powerpc64", target_endian="little"))
        ))]
        mod elf {
            pub use super::elfv1::*;
        }

        // ELFv2 is used for Little-Endian powerpc64 and with musl
        #[cfg(any(
            all(target_arch = "powerpc64", target_endian = "big", target_env = "musl"),
            all(target_arch = "powerpc64", target_endian = "little")
        ))]
        mod elf {
            pub use super::elfv2::*;
        }

        pub use elf::FFI_TRAMPOLINE_SIZE;
        use elf::STRUCT_ALIGN_FLAG;

        mod long_double_64 {
            pub const LONG_DOUBLE_128_FLAG: crate::ffi_abi = 0b0;
        }

        mod long_double_128 {
            pub const LONG_DOUBLE_128_FLAG: crate::ffi_abi =
                super::ffi_abi_FFI_LINUX_LONG_DOUBLE_128;
        }

        // IEEE128 is not supported on BSD or when targeting musl:
        // https://github.com/rust-lang/llvm-project/blob/cb7f903994646c5b9223e0bb6cee3792190991f7/clang/lib/Basic/Targets/PPC.h#L417

        #[cfg(any(target_os = "netbsd", target_os = "freebsd", target_env = "musl"))]
        use long_double_64::*;

        #[cfg(not(any(target_os = "netbsd", target_os = "freebsd", target_env = "musl")))]
        use long_double_128::*;

        pub const ffi_abi_FFI_DEFAULT_ABI: ffi_abi =
            ffi_abi_FFI_LINUX | STRUCT_ALIGN_FLAG | LONG_DOUBLE_128_FLAG;

        pub const FFI_NATIVE_RAW_API: u32 = 0;
        pub const FFI_GO_CLOSURES: u32 = 1;
    }
}

#[cfg(target_arch = "powerpc")]
pub use powerpc::powerpc::*;

#[cfg(target_arch = "powerpc64")]
pub use powerpc::powerpc64::*;