//! Contains architecture-specific types and modules

use capstone::Capstone;
use constants::Endian;
use error::CsResult;
use std::marker::PhantomData;

macro_rules! define_subset_enum {
    ( [
        $subset_enum:ident = $base_enum:ident
      ]
      $( $variant:ident, )*
    ) => {
        #[derive(Copy, Clone, Debug, Eq, Hash, PartialEq)]
        pub enum $subset_enum {
            $(
                $variant,
            )*
        }

        impl From<$subset_enum> for $base_enum {
            fn from(other: $subset_enum) -> $base_enum {
                match other {
                    $(
                        $subset_enum::$variant => $base_enum::$variant,
                    )*
                }
            }
        }
    };
}

macro_rules! define_arch_builder {
    // ExtraMode rules
    ( @extra_modes () ) => {};
    ( @extra_modes ( $( $extra_mode:ident, )+ ) ) => {
        impl super::BuildsCapstoneExtraMode<ArchMode, ArchExtraMode> for ArchCapstoneBuilder {
            fn extra_mode<T: Iterator<Item=ArchExtraMode>>(&mut self, extra_mode: T) -> & mut Self {
                // self.extra_mode = extra_mode.fold(0usize, |acc, x|
                //     acc | cs_mode::from(x) as usize);
                self.extra_mode.clear();
                self.extra_mode.extend(extra_mode);
                self
            }
        }
    };

    // Syntax rules
    ( @syntax () ) => {};
    ( @syntax ( $( $syntax:ident, )+ ) ) => {
        impl super::BuildsCapstoneSyntax<ArchMode, ArchSyntax> for ArchCapstoneBuilder {
            fn syntax(& mut self, syntax: ArchSyntax) -> &mut Self {
                self.syntax = Some(syntax);
                self
            }
        }
    };

    // Endian rules
    ( @endian ( false) ) => {};
    ( @endian ( true ) ) => {
        impl super::BuildsCapstoneEndian<ArchMode> for ArchCapstoneBuilder {
            fn endian(&mut self, endian: Endian) -> &mut Self {
                self.endian = Some(endian);
                self
            }
        }
    };

    // Entrance rule
    (
        $( [
            ( $arch:ident, $arch_variant:ident )
            ( mode: $( $mode:ident, )+ )
            ( extra_modes: $( $extra_mode:ident, )* )
            ( syntax: $( $syntax:ident, )* )
            ( both_endian: $( $endian:ident )* )
        ] )+
    ) => {
        $(
            pub mod $arch {
                use capstone::Capstone;
                use constants::{Arch, Endian, ExtraMode, Mode, Syntax};
                use error::{CsResult, Error};

                define_arch_builder!( @syntax ( $( $syntax, )* ) );
                define_arch_builder!( @endian ( $( $endian )* ) );
                define_arch_builder!( @extra_modes ( $( $extra_mode, )* ) );

                define_subset_enum!(
                    [ ArchMode = Mode ]
                    $( $mode, )*
                );

                define_subset_enum!(
                    [ ArchExtraMode = ExtraMode ]
                    $( $extra_mode, )*
                );

                define_subset_enum!(
                    [ ArchSyntax = Syntax ]
                    $( $syntax, )*
                );

                pub struct ArchCapstoneBuilder {
                    pub(crate) mode: Option<ArchMode>,
                    pub(crate) is_detail: bool,
                    pub(crate) extra_mode: Vec<ArchExtraMode>,
                    pub(crate) syntax: Option<ArchSyntax>,
                    pub(crate) endian: Option<Endian>,
                }

                impl super::BuildsCapstone<ArchMode> for ArchCapstoneBuilder {
                    fn mode(&mut self, mode: ArchMode) -> &mut Self {
                        self.mode = Some(mode);
                        self
                    }

                    fn detail(&mut self, enable_detail: bool) -> &mut Self {
                        self.is_detail = enable_detail;
                        self
                    }

                    fn build(&mut self) -> CsResult<Capstone> {
                        let mode = match self.mode {
                            Some(mode) => mode,
                            None => {
                                let msg: &'static str = concat!(
                                    "Must specify mode for ",
                                    stringify!($arch),
                                    "::ArchCapstoneBuilder with `mode()` method",
                                );
                                return Err(Error::CustomError(msg));
                            }
                        };
                        let extra_mode = self.extra_mode.iter().map(|x| ExtraMode::from(*x));
                        let mut capstone = Capstone::new_raw(Arch::$arch_variant,
                                                             mode.into(),
                                                             extra_mode,
                                                             self.endian)?;

                        if let Some(syntax) = self.syntax {
                            capstone.set_syntax(Syntax::from(syntax))?;
                        }
                        if self.is_detail {
                            capstone.set_detail(self.is_detail)?;
                        }

                        Ok(capstone)
                    }
                }

                impl Default for ArchCapstoneBuilder {
                    fn default() -> Self {
                        ArchCapstoneBuilder {
                            mode: None,
                            is_detail: false,
                            extra_mode: vec![],
                            endian: None,
                            syntax: None,
                        }
                    }
                }
            }
        )+


        impl CapstoneBuilder {
            pub(crate) fn new() -> Self {
                CapstoneBuilder(PhantomData)
            }

            $(
                pub fn $arch(self) -> $arch::ArchCapstoneBuilder {
                    Default::default()
                }
            )*
        }
    }
}

/// Builds a `Capstone` struct
pub trait BuildsCapstone<ArchMode> {
    /// Set the disassembly mode
    fn mode(&mut self, mode: ArchMode) -> &mut Self;

    /// Enable detailed output
    fn detail(&mut self, enable_detail: bool) -> &mut Self;

    /// Get final `Capstone`
    fn build(&mut self) -> CsResult<Capstone>;
}

/// Implies that a `CapstoneBuilder` architecture has extra modes
pub trait BuildsCapstoneExtraMode<ArchMode, ArchExtraMode>
    : BuildsCapstone<ArchMode> {
    /// Set architecture endianness
    fn extra_mode<T: Iterator<Item = ArchExtraMode>>(&mut self, extra_mode: T) -> &mut Self;
}

/// Implies that a `CapstoneBuilder` has different syntax options
pub trait BuildsCapstoneSyntax<ArchMode, ArchSyntax>: BuildsCapstone<ArchMode> {
    /// Set the disassembly syntax
    fn syntax(&mut self, syntax: ArchSyntax) -> &mut Self;
}

/// Implies that a `CapstoneBuilder` architecture has a configurable endianness
pub trait BuildsCapstoneEndian<ArchMode>: BuildsCapstone<ArchMode> {
    /// Set architecture endianness
    fn endian(&mut self, endian: Endian) -> &mut Self;
}

define_arch_builder!(
    [
        ( arm, ARM )
        ( mode:
            Arm,
            Thumb,
            )
        ( extra_modes:
            MClass,
            V8,
            )
        ( syntax:
            NoRegName,
            )
        ( both_endian: true )
    ]
    [
        ( arm64, ARM64 )
        ( mode:
            Arm,
            )
        ( extra_modes: )
        ( syntax: )
        ( both_endian: true )
    ]
    [
        ( mips, MIPS )
        ( mode:
            Mode32,
            Mode64,
            Mips32R6,
            MipsGP64,
            )
        ( extra_modes:
            Micro,
            )
        ( syntax: )
        ( both_endian: true )
    ]
    [
        ( ppc, PPC )
        ( mode:
            Mode32,
            Mode64,
            )
        ( extra_modes: )
        ( syntax:
            NoRegName,
            )
        ( both_endian: true )
    ]
    [
        ( sparc, SPARC )
        ( mode:
            Default,
            V9,
            )
        ( extra_modes: )
        ( syntax: )
        ( both_endian: false )
    ]
    [
        ( sysz, SYSZ )
        ( mode:
            Default,
            )
        ( extra_modes: )
        ( syntax: )
        ( both_endian: false )
    ]
    [
        ( x86, X86 )
        ( mode:
            Mode16,
            Mode32,
            Mode64,
            )
        ( extra_modes: )
        ( syntax:
            Intel,
            Att,
            )
        ( both_endian: false )
    ]
    [
        ( xcore, XCORE )
        ( mode:
            Default,
            )
        ( extra_modes: )
        ( syntax: )
        ( both_endian: false  )
    ]
);

/// Builds `Capstone` object
pub struct CapstoneBuilder(
    /// Hidden field to prevent users from instantiating `CapstoneBuilder`
    PhantomData<()>
);