core-foundation-rs/src/image.rs

use core_foundation::base::{CFRetain, CFTypeID, CFTypeRef, TCFType};
use core_foundation::data::CFData;
use color_space::{CGColorSpace, CGColorSpaceRef};
use data_provider::{CGDataProvider, CGDataProviderRef};
use libc::size_t;
use std::ops::Deref;
use std::mem;

#[repr(C)]
pub enum CGImageAlphaInfo {
    CGImageAlphaNone, /* For example, RGB. */
    CGImageAlphaPremultipliedLast, /* For example, premultiplied RGBA */ 
    CGImageAlphaPremultipliedFirst, /* For example, premultiplied ARGB */
    CGImageAlphaLast, /* For example, non-premultiplied RGBA */
    CGImageAlphaFirst, /* For example, non-premultiplied ARGB */
    CGImageAlphaNoneSkipLast, /* For example, RBGX. */
    CGImageAlphaNoneSkipFirst, /* For example, XRBG. */
    CGImageAlphaOnly /* No color data, alpha data only */
}

#[repr(C)]
pub enum CGImageByteOrderInfo {
    CGImageByteOrderMask = 0x7000,
    CGImageByteOrder16Little = (1 << 12),
    CGImageByteOrder32Little = (2 << 12),
    CGImageByteOrder16Big = (3 << 12),
    CGImageByteOrder32Big = (4 << 12)
}

#[repr(C)]
pub struct __CGImage;

pub type CGImageRef = *const __CGImage;

pub struct CGImage {
    obj: CGImageRef,
}

impl Drop for CGImage {
    fn drop(&mut self) {
        unsafe {
            CGImageRelease(self.as_concrete_TypeRef())
        }
    }
}

impl Clone for CGImage {
    fn clone(&self) -> CGImage {
        unsafe {
            TCFType::wrap_under_get_rule(self.as_concrete_TypeRef())
        }
    }
}

// TODO: Replace all this stuff by simply using:
// impl_TCFType!(CGImage, CGImageRef, CGImageGetTypeID);
impl TCFType<CGImageRef> for CGImage {
    #[inline]
    fn as_concrete_TypeRef(&self) -> CGImageRef {
        self.obj
    }

    #[inline]
    unsafe fn wrap_under_get_rule(reference: CGImageRef) -> CGImage {
        let reference: CGImageRef = mem::transmute(CFRetain(mem::transmute(reference)));
        TCFType::wrap_under_create_rule(reference)
    }

    #[inline]
    fn as_CFTypeRef(&self) -> CFTypeRef {
        unsafe {
            mem::transmute(self.as_concrete_TypeRef())
        }
    }

    #[inline]
    unsafe fn wrap_under_create_rule(obj: CGImageRef) -> CGImage {
        CGImage {
            obj: obj,
        }
    }

    #[inline]
    fn type_id() -> CFTypeID {
        unsafe {
            CGImageGetTypeID()
        }
    }
}

impl CGImage {
    pub fn width(&self) -> size_t {
        unsafe {
            CGImageGetWidth(self.as_concrete_TypeRef())
        }
    }

    pub fn height(&self) -> size_t {
        unsafe {
            CGImageGetHeight(self.as_concrete_TypeRef())
        }
    }

    pub fn bits_per_component(&self) -> size_t {
        unsafe {
            CGImageGetBitsPerComponent(self.as_concrete_TypeRef())
        }
    }

    pub fn bits_per_pixel(&self) -> size_t {
        unsafe {
            CGImageGetBitsPerPixel(self.as_concrete_TypeRef())
        }
    }

    pub fn bytes_per_row(&self) -> size_t {
        unsafe {
            CGImageGetBytesPerRow(self.as_concrete_TypeRef())
        }
    }

    pub fn color_space(&self) -> CGColorSpace {
        unsafe {
            TCFType::wrap_under_get_rule(CGImageGetColorSpace(self.as_concrete_TypeRef()))
        }
    }

    /// Returns the raw image bytes wrapped in `CFData`. Note, the returned `CFData` owns the
    /// underlying buffer.
    pub fn data(&self) -> CFData {
        let data_provider = unsafe {
            CGDataProvider::wrap_under_get_rule(CGImageGetDataProvider(self.as_concrete_TypeRef()))
        };
        data_provider.copy_data()
    }
}

impl Deref for CGImage {
    type Target = CGImageRef;

    #[inline]
    fn deref(&self) -> &CGImageRef {
        &self.obj
    }
}

#[link(name = "ApplicationServices", kind = "framework")]
extern {
    fn CGImageGetTypeID() -> CFTypeID;
    fn CGImageGetWidth(image: CGImageRef) -> size_t;
    fn CGImageGetHeight(image: CGImageRef) -> size_t;
    fn CGImageGetBitsPerComponent(image: CGImageRef) -> size_t;
    fn CGImageGetBitsPerPixel(image: CGImageRef) -> size_t;
    fn CGImageGetBytesPerRow(image: CGImageRef) -> size_t;
    fn CGImageGetColorSpace(image: CGImageRef) -> CGColorSpaceRef;
    fn CGImageGetDataProvider(image: CGImageRef) -> CGDataProviderRef;
    fn CGImageRelease(image: CGImageRef);

    //fn CGImageGetAlphaInfo(image: CGImageRef) -> CGImageAlphaInfo;
    //fn CGImageCreateCopyWithColorSpace(image: CGImageRef, space: CGColorSpaceRef) -> CGImageRef
}