// Copyright 2020 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

//! rutabaga_utils: Utility enums, structs, and implementations needed by the rest of the crate.

use std::fmt::{self, Display};
use std::io::Error as IoError;
use std::num::TryFromIntError;
use std::os::raw::c_void;
use std::path::PathBuf;
use std::str::Utf8Error;

use base::{Error as SysError, ExternalMappingError, SafeDescriptor};
use data_model::VolatileMemoryError;

#[cfg(feature = "vulkano")]
use vulkano::device::DeviceCreationError;
#[cfg(feature = "vulkano")]
use vulkano::image::ImageCreationError;
#[cfg(feature = "vulkano")]
use vulkano::instance::InstanceCreationError;
#[cfg(feature = "vulkano")]
use vulkano::memory::DeviceMemoryAllocError;

/// Represents a buffer.  `base` contains the address of a buffer, while `len` contains the length
/// of the buffer.
#[derive(Copy, Clone)]
pub struct RutabagaIovec {
    pub base: *mut c_void,
    pub len: usize,
}

/// 3D resource creation parameters.  Also used to create 2D resource.  Constants based on Mesa's
/// (internal) Gallium interface.  Not in the virtio-gpu spec, but should be since dumb resources
/// can't work with gfxstream/virglrenderer without this.
pub const RUTABAGA_PIPE_TEXTURE_2D: u32 = 2;
pub const RUTABAGA_PIPE_BIND_RENDER_TARGET: u32 = 2;
#[derive(Copy, Clone, Debug)]
pub struct ResourceCreate3D {
    pub target: u32,
    pub format: u32,
    pub bind: u32,
    pub width: u32,
    pub height: u32,
    pub depth: u32,
    pub array_size: u32,
    pub last_level: u32,
    pub nr_samples: u32,
    pub flags: u32,
}

/// Blob resource creation parameters.
pub const RUTABAGA_BLOB_MEM_GUEST: u32 = 0x0001;
pub const RUTABAGA_BLOB_MEM_HOST3D: u32 = 0x0002;
pub const RUTABAGA_BLOB_MEM_HOST3D_GUEST: u32 = 0x0003;

pub const RUTABAGA_BLOB_FLAG_USE_MAPPABLE: u32 = 0x0001;
pub const RUTABAGA_BLOB_FLAG_USE_SHAREABLE: u32 = 0x0002;
pub const RUTABAGA_BLOB_FLAG_USE_CROSS_DEVICE: u32 = 0x0004;
#[derive(Copy, Clone, Debug)]
pub struct ResourceCreateBlob {
    pub blob_mem: u32,
    pub blob_flags: u32,
    pub blob_id: u64,
    pub size: u64,
}

/// Metadata associated with a swapchain, video or camera image.
#[derive(Default, Copy, Clone, Debug)]
pub struct Resource3DInfo {
    pub width: u32,
    pub height: u32,
    pub drm_fourcc: u32,
    pub strides: [u32; 4],
    pub offsets: [u32; 4],
    pub modifier: u64,
}

/// Memory index and physical device index of the associated VkDeviceMemory.
#[derive(Copy, Clone, Default)]
pub struct VulkanInfo {
    pub memory_idx: u32,
    pub physical_device_idx: u32,
}

/// Rutabaga context init capset id mask (not upstreamed).
pub const RUTABAGA_CONTEXT_INIT_CAPSET_ID_MASK: u32 = 0x00ff;

/// Rutabaga flags for creating fences (fence ctx idx info not upstreamed).
pub const RUTABAGA_FLAG_FENCE: u32 = 1 << 0;
pub const RUTABAGA_FLAG_INFO_FENCE_CTX_IDX: u32 = 1 << 1;

/// Convenience struct for Rutabaga fences
pub struct RutabagaFenceData {
    pub flags: u32,
    pub fence_id: u64,
    pub ctx_id: u32,
    pub fence_ctx_idx: u32,
}

/// Mapped memory caching flags (see virtio_gpu spec)
pub const RUTABAGA_MAP_CACHE_CACHED: u32 = 0x01;
pub const RUTABAGA_MAP_CACHE_UNCACHED: u32 = 0x02;
pub const RUTABAGA_MAP_CACHE_WC: u32 = 0x03;

/// Rutabaga capsets.
pub const RUTABAGA_CAPSET_VIRGL: u32 = 1;
pub const RUTABAGA_CAPSET_VIRGL2: u32 = 2;
/// The following capsets are not upstreamed.
pub const RUTABAGA_CAPSET_GFXSTREAM: u32 = 3;
pub const RUTABAGA_CAPSET_VENUS: u32 = 4;
pub const RUTABAGA_CAPSET_CROSS_DOMAIN: u32 = 5;

/// An error generated while using this crate.
#[derive(Debug)]
pub enum RutabagaError {
    /// Indicates `Rutabaga` was already initialized since only one Rutabaga instance per process
    /// is allowed.
    AlreadyInUse,
    /// Checked Arithmetic error
    CheckedArithmetic {
        field1: (&'static str, usize),
        field2: (&'static str, usize),
        op: &'static str,
    },
    /// Checked Range error
    CheckedRange {
        field1: (&'static str, usize),
        field2: (&'static str, usize),
    },
    /// The Rutabaga component failed to export a RutabagaHandle.
    ExportedRutabagaHandle,
    /// Invalid Capset
    InvalidCapset,
    /// A command size was submitted that was invalid.
    InvalidCommandSize(usize),
    /// Invalid RutabagaComponent
    InvalidComponent,
    /// Invalid Context ID
    InvalidContextId,
    /// The indicated region of guest memory is invalid.
    InvalidIovec,
    /// Invalid Resource ID.
    InvalidResourceId,
    /// Indicates an error in the RutabagaBuilder.
    InvalidRutabagaBuild,
    /// An input/output error occured.
    IoError(IoError),
    /// The mapping failed.
    MappingFailed(ExternalMappingError),
    /// An internal Rutabaga component error was returned.
    ComponentError(i32),
    /// Violation of the Rutabaga spec occured.
    SpecViolation,
    /// System error returned as a result of rutabaga library operation.
    SysError(SysError),
    /// An attempted integer conversion failed.
    TryFromIntError(TryFromIntError),
    /// The command is unsupported.
    Unsupported,
    /// Utf8 error.
    Utf8Error(Utf8Error),
    /// Volatile memory error
    VolatileMemoryError(VolatileMemoryError),
    /// Image creation error
    #[cfg(feature = "vulkano")]
    VkImageCreationError(ImageCreationError),
    /// Instance creation error
    #[cfg(feature = "vulkano")]
    VkInstanceCreationError(InstanceCreationError),
    /// Device creation error
    #[cfg(feature = "vulkano")]
    VkDeviceCreationError(DeviceCreationError),
    /// Device memory allocation error
    #[cfg(feature = "vulkano")]
    VkDeviceMemoryAllocError(DeviceMemoryAllocError),
}

impl Display for RutabagaError {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        use self::RutabagaError::*;
        match self {
            AlreadyInUse => write!(f, "attempted to use a rutabaga asset already in use"),
            CheckedArithmetic {
                field1: (label1, value1),
                field2: (label2, value2),
                op,
            } => write!(
                f,
                "arithmetic failed: {}({}) {} {}({})",
                label1, value1, op, label2, value2
            ),
            CheckedRange {
                field1: (label1, value1),
                field2: (label2, value2),
            } => write!(
                f,
                "range check failed: {}({}) vs {}({})",
                label1, value1, label2, value2
            ),
            ExportedRutabagaHandle => write!(f, "failed to export Rutabaga handle"),
            InvalidCapset => write!(f, "invalid capset"),
            InvalidCommandSize(s) => write!(f, "command buffer submitted with invalid size: {}", s),
            InvalidComponent => write!(f, "invalid rutabaga component"),
            InvalidContextId => write!(f, "invalid context id"),
            InvalidIovec => write!(f, "an iovec is outside of guest memory's range"),
            InvalidResourceId => write!(f, "invalid resource id"),
            InvalidRutabagaBuild => write!(f, "invalid rutabaga build parameters"),
            IoError(e) => write!(f, "an input/output error occur: {}", e),
            MappingFailed(s) => write!(f, "The mapping failed for the following reason: {}", s),
            ComponentError(ret) => write!(f, "rutabaga component failed with error {}", ret),
            SpecViolation => write!(f, "violation of the rutabaga spec"),
            SysError(e) => write!(f, "rutabaga received a system error: {}", e),
            TryFromIntError(e) => write!(f, "int conversion failed: {}", e),
            Unsupported => write!(f, "feature or function unsupported"),
            Utf8Error(e) => write!(f, "an utf8 error occured: {}", e),
            VolatileMemoryError(e) => write!(f, "noticed a volatile memory error {}", e),
            #[cfg(feature = "vulkano")]
            VkDeviceCreationError(e) => write!(f, "vulkano device creation failure {}", e),
            #[cfg(feature = "vulkano")]
            VkDeviceMemoryAllocError(e) => {
                write!(f, "vulkano device memory allocation failure {}", e)
            }
            #[cfg(feature = "vulkano")]
            VkImageCreationError(e) => write!(f, "vulkano image creation failure {}", e),
            #[cfg(feature = "vulkano")]
            VkInstanceCreationError(e) => write!(f, "vulkano instance creation failure {}", e),
        }
    }
}

impl From<IoError> for RutabagaError {
    fn from(e: IoError) -> RutabagaError {
        RutabagaError::IoError(e)
    }
}

impl From<SysError> for RutabagaError {
    fn from(e: SysError) -> RutabagaError {
        RutabagaError::SysError(e)
    }
}

impl From<TryFromIntError> for RutabagaError {
    fn from(e: TryFromIntError) -> RutabagaError {
        RutabagaError::TryFromIntError(e)
    }
}

impl From<Utf8Error> for RutabagaError {
    fn from(e: Utf8Error) -> RutabagaError {
        RutabagaError::Utf8Error(e)
    }
}

impl From<VolatileMemoryError> for RutabagaError {
    fn from(e: VolatileMemoryError) -> RutabagaError {
        RutabagaError::VolatileMemoryError(e)
    }
}

/// The result of an operation in this crate.
pub type RutabagaResult<T> = std::result::Result<T, RutabagaError>;

/// Flags for virglrenderer.  Copied from virglrenderer bindings.
const VIRGLRENDERER_USE_EGL: u32 = 1 << 0;
#[allow(dead_code)]
const VIRGLRENDERER_THREAD_SYNC: u32 = 1 << 1;
const VIRGLRENDERER_USE_GLX: u32 = 1 << 2;
const VIRGLRENDERER_USE_SURFACELESS: u32 = 1 << 3;
const VIRGLRENDERER_USE_GLES: u32 = 1 << 4;
const VIRGLRENDERER_USE_EXTERNAL_BLOB: u32 = 1 << 5;
const VIRGLRENDERER_VENUS: u32 = 1 << 6;
const VIRGLRENDERER_NO_VIRGL: u32 = 1 << 7;

/// virglrenderer flag struct.
#[derive(Copy, Clone)]
pub struct VirglRendererFlags(u32);

impl Default for VirglRendererFlags {
    fn default() -> VirglRendererFlags {
        VirglRendererFlags::new()
            .use_virgl(true)
            .use_venus(false)
            .use_egl(true)
            .use_surfaceless(true)
            .use_gles(true)
    }
}

impl From<VirglRendererFlags> for i32 {
    fn from(flags: VirglRendererFlags) -> i32 {
        flags.0 as i32
    }
}

impl VirglRendererFlags {
    /// Create new virglrenderer flags.
    pub fn new() -> VirglRendererFlags {
        VirglRendererFlags(0)
    }

    fn set_flag(self, bitmask: u32, set: bool) -> VirglRendererFlags {
        if set {
            VirglRendererFlags(self.0 | bitmask)
        } else {
            VirglRendererFlags(self.0 & (!bitmask))
        }
    }

    /// Enable virgl support
    pub fn use_virgl(self, v: bool) -> VirglRendererFlags {
        self.set_flag(VIRGLRENDERER_NO_VIRGL, !v)
    }

    /// Enable venus support
    pub fn use_venus(self, v: bool) -> VirglRendererFlags {
        self.set_flag(VIRGLRENDERER_VENUS, v)
    }

    /// Use EGL for context creation.
    pub fn use_egl(self, v: bool) -> VirglRendererFlags {
        self.set_flag(VIRGLRENDERER_USE_EGL, v)
    }

    /// Use GLX for context creation.
    pub fn use_glx(self, v: bool) -> VirglRendererFlags {
        self.set_flag(VIRGLRENDERER_USE_GLX, v)
    }

    /// No surfaces required when creating context.
    pub fn use_surfaceless(self, v: bool) -> VirglRendererFlags {
        self.set_flag(VIRGLRENDERER_USE_SURFACELESS, v)
    }

    /// Use GLES drivers.
    pub fn use_gles(self, v: bool) -> VirglRendererFlags {
        self.set_flag(VIRGLRENDERER_USE_GLES, v)
    }

    /// Use external memory when creating blob resources.
    pub fn use_external_blob(self, v: bool) -> VirglRendererFlags {
        self.set_flag(VIRGLRENDERER_USE_EXTERNAL_BLOB, v)
    }
}

/// Flags for the gfxstream renderer.
const GFXSTREAM_RENDERER_FLAGS_USE_EGL: u32 = 1 << 0;
#[allow(dead_code)]
const GFXSTREAM_RENDERER_FLAGS_THREAD_SYNC: u32 = 1 << 1;
const GFXSTREAM_RENDERER_FLAGS_USE_GLX: u32 = 1 << 2;
const GFXSTREAM_RENDERER_FLAGS_USE_SURFACELESS: u32 = 1 << 3;
const GFXSTREAM_RENDERER_FLAGS_USE_GLES: u32 = 1 << 4;
const GFXSTREAM_RENDERER_FLAGS_NO_VK_BIT: u32 = 1 << 5;
const GFXSTREAM_RENDERER_FLAGS_NO_SYNCFD_BIT: u32 = 1 << 20;
const GFXSTREAM_RENDERER_FLAGS_GUEST_USES_ANGLE: u32 = 1 << 21;

/// gfxstream flag struct.
#[derive(Copy, Clone, Default)]
pub struct GfxstreamFlags(u32);

impl GfxstreamFlags {
    /// Create new gfxstream flags.
    pub fn new() -> GfxstreamFlags {
        GfxstreamFlags(0)
    }

    fn set_flag(self, bitmask: u32, set: bool) -> GfxstreamFlags {
        if set {
            GfxstreamFlags(self.0 | bitmask)
        } else {
            GfxstreamFlags(self.0 & (!bitmask))
        }
    }

    /// Use EGL for context creation.
    pub fn use_egl(self, v: bool) -> GfxstreamFlags {
        self.set_flag(GFXSTREAM_RENDERER_FLAGS_USE_EGL, v)
    }

    /// Use GLX for context creation.
    pub fn use_glx(self, v: bool) -> GfxstreamFlags {
        self.set_flag(GFXSTREAM_RENDERER_FLAGS_USE_GLX, v)
    }

    /// No surfaces required when creating context.
    pub fn use_surfaceless(self, v: bool) -> GfxstreamFlags {
        self.set_flag(GFXSTREAM_RENDERER_FLAGS_USE_SURFACELESS, v)
    }

    /// Use GLES drivers.
    pub fn use_gles(self, v: bool) -> GfxstreamFlags {
        self.set_flag(GFXSTREAM_RENDERER_FLAGS_USE_GLES, v)
    }

    /// Use external synchronization.
    pub fn use_syncfd(self, v: bool) -> GfxstreamFlags {
        self.set_flag(GFXSTREAM_RENDERER_FLAGS_NO_SYNCFD_BIT, !v)
    }

    /// Support using Vulkan.
    pub fn use_vulkan(self, v: bool) -> GfxstreamFlags {
        self.set_flag(GFXSTREAM_RENDERER_FLAGS_NO_VK_BIT, !v)
    }

    /// Use ANGLE as the guest GLES driver.
    pub fn use_guest_angle(self, v: bool) -> GfxstreamFlags {
        self.set_flag(GFXSTREAM_RENDERER_FLAGS_GUEST_USES_ANGLE, v)
    }
}

impl From<GfxstreamFlags> for i32 {
    fn from(flags: GfxstreamFlags) -> i32 {
        flags.0 as i32
    }
}

/// Transfers {to, from} 1D buffers, 2D textures, 3D textures, and cubemaps.
#[derive(Debug)]
pub struct Transfer3D {
    pub x: u32,
    pub y: u32,
    pub z: u32,
    pub w: u32,
    pub h: u32,
    pub d: u32,
    pub level: u32,
    pub stride: u32,
    pub layer_stride: u32,
    pub offset: u64,
}

impl Transfer3D {
    /// Constructs a 2 dimensional XY box in 3 dimensional space with unit depth and zero
    /// displacement on the Z axis.
    pub fn new_2d(x: u32, y: u32, w: u32, h: u32) -> Transfer3D {
        Transfer3D {
            x,
            y,
            z: 0,
            w,
            h,
            d: 1,
            level: 0,
            stride: 0,
            layer_stride: 0,
            offset: 0,
        }
    }

    /// Returns true if this box represents a volume of zero.
    pub fn is_empty(&self) -> bool {
        self.w == 0 || self.h == 0 || self.d == 0
    }
}

/// Rutabaga channel types
pub const RUTABAGA_CHANNEL_TYPE_WAYLAND: u32 = 0x0001;
pub const RUTABAGA_CHANNEL_TYPE_CAMERA: u32 = 0x0002;

/// Information needed to open an OS-specific RutabagaConnection (TBD).  Only Linux hosts are
/// considered at the moment.
#[derive(Clone)]
pub struct RutabagaChannel {
    pub base_channel: PathBuf,
    pub channel_type: u32,
}

/// Enumeration of possible rutabaga components.
#[derive(Copy, Clone, Eq, PartialEq, PartialOrd, Ord)]
pub enum RutabagaComponentType {
    Rutabaga2D,
    VirglRenderer,
    Gfxstream,
    CrossDomain,
}

/// Rutabaga handle types (memory and sync in same namespace)
pub const RUTABAGA_MEM_HANDLE_TYPE_OPAQUE_FD: u32 = 0x0001;
pub const RUTABAGA_MEM_HANDLE_TYPE_DMABUF: u32 = 0x0002;
pub const RUTABAGE_MEM_HANDLE_TYPE_OPAQUE_WIN32: u32 = 0x0003;
pub const RUTABAGA_FENCE_HANDLE_TYPE_OPAQUE_FD: u32 = 0x0004;
pub const RUTABAGA_FENCE_HANDLE_TYPE_SYNC_FD: u32 = 0x0005;
pub const RUTABAGE_FENCE_HANDLE_TYPE_OPAQUE_WIN32: u32 = 0x0006;

/// Handle to OS-specific memory or synchronization objects.
pub struct RutabagaHandle {
    pub os_handle: SafeDescriptor,
    pub handle_type: u32,
}

impl RutabagaHandle {
    /// Clones an existing rutabaga handle, by using OS specific mechanisms.
    pub fn try_clone(&self) -> RutabagaResult<RutabagaHandle> {
        let clone = self
            .os_handle
            .try_clone()
            .map_err(|_| RutabagaError::Unsupported)?;
        Ok(RutabagaHandle {
            os_handle: clone,
            handle_type: self.handle_type,
        })
    }
}