// Copyright 2021-2022 Vector 35 Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! Contains all information related to the execution environment of the binary, mainly the calling conventions used

use std::{borrow::Borrow, collections::HashMap, os::raw, path::Path, ptr, slice};

use binaryninjacore_sys::*;

use crate::{
    architecture::{Architecture, CoreArchitecture},
    callingconvention::CallingConvention,
    rc::*,
    string::*,
    types::{QualifiedName, QualifiedNameAndType, Type},
};

#[derive(PartialEq, Eq, Hash)]
pub struct Platform {
    pub(crate) handle: *mut BNPlatform,
}

unsafe impl Send for Platform {}
unsafe impl Sync for Platform {}

macro_rules! cc_func {
    ($get_name:ident, $get_api:ident, $set_name:ident, $set_api:ident) => {
        pub fn $get_name(&self) -> Option<Ref<CallingConvention<CoreArchitecture>>> {
            let arch = self.arch();

            unsafe {
                let cc = $get_api(self.handle);

                if cc.is_null() {
                    None
                } else {
                    Some(CallingConvention::ref_from_raw(cc, arch))
                }
            }
        }

        pub fn $set_name<A: Architecture>(&self, cc: &CallingConvention<A>) {
            let arch = self.arch();

            assert!(
                cc.arch_handle.borrow().as_ref().0 == arch.0,
                "use of calling convention with non-matching Platform architecture!"
            );

            unsafe {
                $set_api(self.handle, cc.handle);
            }
        }
    };
}

impl Platform {
    pub(crate) unsafe fn ref_from_raw(handle: *mut BNPlatform) -> Ref<Self> {
        debug_assert!(!handle.is_null());

        Ref::new(Self { handle })
    }

    pub fn by_name<S: BnStrCompatible>(name: S) -> Option<Ref<Self>> {
        let raw_name = name.into_bytes_with_nul();
        unsafe {
            let res = BNGetPlatformByName(raw_name.as_ref().as_ptr() as *mut _);

            if res.is_null() {
                None
            } else {
                Some(Ref::new(Self { handle: res }))
            }
        }
    }

    pub fn list_all() -> Array<Platform> {
        unsafe {
            let mut count = 0;
            let handles = BNGetPlatformList(&mut count);

            Array::new(handles, count, ())
        }
    }

    pub fn list_by_arch(arch: &CoreArchitecture) -> Array<Platform> {
        unsafe {
            let mut count = 0;
            let handles = BNGetPlatformListByArchitecture(arch.0, &mut count);

            Array::new(handles, count, ())
        }
    }

    pub fn list_by_os<S: BnStrCompatible>(name: S) -> Array<Platform> {
        let raw_name = name.into_bytes_with_nul();

        unsafe {
            let mut count = 0;
            let handles = BNGetPlatformListByOS(raw_name.as_ref().as_ptr() as *mut _, &mut count);

            Array::new(handles, count, ())
        }
    }

    pub fn list_by_os_and_arch<S: BnStrCompatible>(
        name: S,
        arch: &CoreArchitecture,
    ) -> Array<Platform> {
        let raw_name = name.into_bytes_with_nul();

        unsafe {
            let mut count = 0;
            let handles = BNGetPlatformListByOSAndArchitecture(
                raw_name.as_ref().as_ptr() as *mut _,
                arch.0,
                &mut count,
            );

            Array::new(handles, count, ())
        }
    }

    pub fn list_available_os() -> Array<BnString> {
        unsafe {
            let mut count = 0;
            let list = BNGetPlatformOSList(&mut count);

            Array::new(list, count, ())
        }
    }

    pub fn new<A: Architecture, S: BnStrCompatible>(arch: &A, name: S) -> Ref<Self> {
        let name = name.into_bytes_with_nul();
        unsafe {
            let handle = BNCreatePlatform(arch.as_ref().0, name.as_ref().as_ptr() as *mut _);

            assert!(!handle.is_null());

            Ref::new(Self { handle })
        }
    }

    pub fn name(&self) -> BnString {
        unsafe {
            let raw_name = BNGetPlatformName(self.handle);
            BnString::from_raw(raw_name)
        }
    }

    pub fn arch(&self) -> CoreArchitecture {
        unsafe { CoreArchitecture::from_raw(BNGetPlatformArchitecture(self.handle)) }
    }

    pub fn register_os<S: BnStrCompatible>(&self, os: S) {
        let os = os.into_bytes_with_nul();

        unsafe {
            BNRegisterPlatform(os.as_ref().as_ptr() as *mut _, self.handle);
        }
    }

    cc_func!(
        get_default_calling_convention,
        BNGetPlatformDefaultCallingConvention,
        set_default_calling_convention,
        BNRegisterPlatformDefaultCallingConvention
    );

    cc_func!(
        get_cdecl_calling_convention,
        BNGetPlatformCdeclCallingConvention,
        set_cdecl_calling_convention,
        BNRegisterPlatformCdeclCallingConvention
    );

    cc_func!(
        get_stdcall_calling_convention,
        BNGetPlatformStdcallCallingConvention,
        set_stdcall_calling_convention,
        BNRegisterPlatformStdcallCallingConvention
    );

    cc_func!(
        get_fastcall_calling_convention,
        BNGetPlatformFastcallCallingConvention,
        set_fastcall_calling_convention,
        BNRegisterPlatformFastcallCallingConvention
    );

    cc_func!(
        get_syscall_convention,
        BNGetPlatformSystemCallConvention,
        set_syscall_convention,
        BNSetPlatformSystemCallConvention
    );

    pub fn calling_conventions(&self) -> Array<CallingConvention<CoreArchitecture>> {
        unsafe {
            let mut count = 0;
            let handles = BNGetPlatformCallingConventions(self.handle, &mut count);

            Array::new(handles, count, self.arch())
        }
    }

    pub fn types(&self) -> Array<QualifiedNameAndType> {
        unsafe {
            let mut count = 0;
            let handles = BNGetPlatformTypes(self.handle, &mut count);

            Array::new(handles, count, ())
        }
    }

    pub fn variables(&self) -> Array<QualifiedNameAndType> {
        unsafe {
            let mut count = 0;
            let handles = BNGetPlatformVariables(self.handle, &mut count);

            Array::new(handles, count, ())
        }
    }

    pub fn functions(&self) -> Array<QualifiedNameAndType> {
        unsafe {
            let mut count = 0;
            let handles = BNGetPlatformFunctions(self.handle, &mut count);

            Array::new(handles, count, ())
        }
    }
}

pub trait TypeParser {
    fn parse_types_from_source<S: BnStrCompatible, P: AsRef<Path>>(
        &self,
        _source: S,
        _filename: S,
        _include_directories: &[P],
        _auto_type_source: S,
    ) -> Result<TypeParserResult, String> {
        Err(String::new())
    }
}

#[derive(Clone, Default)]
pub struct TypeParserResult {
    pub types: HashMap<String, Ref<Type>>,
    pub variables: HashMap<String, Ref<Type>>,
    pub functions: HashMap<String, Ref<Type>>,
}

impl TypeParser for Platform {
    fn parse_types_from_source<S: BnStrCompatible, P: AsRef<Path>>(
        &self,
        source: S,
        filename: S,
        include_directories: &[P],
        auto_type_source: S,
    ) -> Result<TypeParserResult, String> {
        let mut result = BNTypeParserResult {
            functionCount: 0,
            typeCount: 0,
            variableCount: 0,
            functions: ptr::null_mut(),
            types: ptr::null_mut(),
            variables: ptr::null_mut(),
        };

        let mut type_parser_result = TypeParserResult::default();

        let mut error_string: *mut raw::c_char = ptr::null_mut();

        let src = source.into_bytes_with_nul();
        let filename = filename.into_bytes_with_nul();
        let auto_type_source = auto_type_source.into_bytes_with_nul();

        let mut include_dirs = vec![];

        for dir in include_directories.iter() {
            let d = dir
                .as_ref()
                .to_string_lossy()
                .to_string()
                .into_bytes_with_nul();
            include_dirs.push(d.as_ptr() as _);
        }

        unsafe {
            let success = BNParseTypesFromSource(
                self.handle,
                src.as_ref().as_ptr() as _,
                filename.as_ref().as_ptr() as _,
                &mut result,
                &mut error_string,
                include_dirs.as_mut_ptr(),
                include_dirs.len(),
                auto_type_source.as_ref().as_ptr() as _,
            );

            let error_msg = BnString::from_raw(error_string);

            if !success {
                return Err(error_msg.to_string());
            }

            for i in slice::from_raw_parts(result.types, result.typeCount) {
                let name = QualifiedName(i.name);
                type_parser_result
                    .types
                    .insert(name.string(), Type::ref_from_raw(i.type_));
            }

            for i in slice::from_raw_parts(result.functions, result.functionCount) {
                let name = QualifiedName(i.name);
                type_parser_result
                    .functions
                    .insert(name.string(), Type::ref_from_raw(i.type_));
            }

            for i in slice::from_raw_parts(result.variables, result.variableCount) {
                let name = QualifiedName(i.name);
                type_parser_result
                    .variables
                    .insert(name.string(), Type::ref_from_raw(i.type_));
            }
        }

        Ok(type_parser_result)
    }
}

impl ToOwned for Platform {
    type Owned = Ref<Self>;

    fn to_owned(&self) -> Self::Owned {
        unsafe { RefCountable::inc_ref(self) }
    }
}

unsafe impl RefCountable for Platform {
    unsafe fn inc_ref(handle: &Self) -> Ref<Self> {
        Ref::new(Self {
            handle: BNNewPlatformReference(handle.handle),
        })
    }

    unsafe fn dec_ref(handle: &Self) {
        BNFreePlatform(handle.handle);
    }
}

impl CoreArrayProvider for Platform {
    type Raw = *mut BNPlatform;
    type Context = ();
}

unsafe impl CoreOwnedArrayProvider for Platform {
    unsafe fn free(raw: *mut *mut BNPlatform, count: usize, _context: &()) {
        BNFreePlatformList(raw, count);
    }
}

unsafe impl<'a> CoreArrayWrapper<'a> for Platform {
    type Wrapped = Guard<'a, Platform>;

    unsafe fn wrap_raw(raw: &'a *mut BNPlatform, context: &'a ()) -> Guard<'a, Platform> {
        debug_assert!(!raw.is_null());
        Guard::new(Platform { handle: *raw }, context)
    }
}