#![allow(unused_variables)]

use std::ops::Range;

#[derive(Clone, Debug)]
pub struct Api;
pub struct Context;
#[derive(Debug)]
pub struct Encoder;
#[derive(Debug)]
pub struct Resource;

type DeviceResult<T> = Result<T, crate::DeviceError>;

impl crate::Api for Api {
    type Instance = Context;
    type Surface = Context;
    type Adapter = Context;
    type Device = Context;

    type Queue = Context;
    type CommandEncoder = Encoder;
    type CommandBuffer = Resource;

    type Buffer = Resource;
    type Texture = Resource;
    type SurfaceTexture = Resource;
    type TextureView = Resource;
    type Sampler = Resource;
    type QuerySet = Resource;
    type Fence = Resource;
    type AccelerationStructure = Resource;

    type BindGroupLayout = Resource;
    type BindGroup = Resource;
    type PipelineLayout = Resource;
    type ShaderModule = Resource;
    type RenderPipeline = Resource;
    type ComputePipeline = Resource;
}

impl crate::Instance for Context {
    type A = Api;

    unsafe fn init(desc: &crate::InstanceDescriptor) -> Result<Self, crate::InstanceError> {
        Ok(Context)
    }
    unsafe fn create_surface(
        &self,
        _display_handle: raw_window_handle::RawDisplayHandle,
        _window_handle: raw_window_handle::RawWindowHandle,
    ) -> Result<Context, crate::InstanceError> {
        Ok(Context)
    }
    unsafe fn destroy_surface(&self, surface: Context) {}
    unsafe fn enumerate_adapters(&self) -> Vec<crate::ExposedAdapter<Api>> {
        Vec::new()
    }
}

impl crate::Surface for Context {
    type A = Api;

    unsafe fn configure(
        &self,
        device: &Context,
        config: &crate::SurfaceConfiguration,
    ) -> Result<(), crate::SurfaceError> {
        Ok(())
    }

    unsafe fn unconfigure(&self, device: &Context) {}

    unsafe fn acquire_texture(
        &self,
        timeout: Option<std::time::Duration>,
        fence: &Resource,
    ) -> Result<Option<crate::AcquiredSurfaceTexture<Api>>, crate::SurfaceError> {
        Ok(None)
    }
    unsafe fn discard_texture(&self, texture: Resource) {}
}

impl crate::Adapter for Context {
    type A = Api;

    unsafe fn open(
        &self,
        features: wgt::Features,
        _limits: &wgt::Limits,
    ) -> DeviceResult<crate::OpenDevice<Api>> {
        Err(crate::DeviceError::Lost)
    }
    unsafe fn texture_format_capabilities(
        &self,
        format: wgt::TextureFormat,
    ) -> crate::TextureFormatCapabilities {
        crate::TextureFormatCapabilities::empty()
    }

    unsafe fn surface_capabilities(&self, surface: &Context) -> Option<crate::SurfaceCapabilities> {
        None
    }

    unsafe fn get_presentation_timestamp(&self) -> wgt::PresentationTimestamp {
        wgt::PresentationTimestamp::INVALID_TIMESTAMP
    }
}

impl crate::Queue for Context {
    type A = Api;

    unsafe fn submit(
        &self,
        command_buffers: &[&Resource],
        surface_textures: &[&Resource],
        signal_fence: (&mut Resource, crate::FenceValue),
    ) -> DeviceResult<()> {
        Ok(())
    }
    unsafe fn present(
        &self,
        surface: &Context,
        texture: Resource,
    ) -> Result<(), crate::SurfaceError> {
        Ok(())
    }

    unsafe fn get_timestamp_period(&self) -> f32 {
        1.0
    }
}

impl crate::Device for Context {
    type A = Api;

    unsafe fn exit(self, queue: Context) {}
    unsafe fn create_buffer(&self, desc: &crate::BufferDescriptor) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn destroy_buffer(&self, buffer: Resource) {}
    unsafe fn map_buffer(
        &self,
        buffer: &Resource,
        range: crate::MemoryRange,
    ) -> DeviceResult<crate::BufferMapping> {
        Err(crate::DeviceError::Lost)
    }
    unsafe fn unmap_buffer(&self, buffer: &Resource) -> DeviceResult<()> {
        Ok(())
    }
    unsafe fn flush_mapped_ranges<I>(&self, buffer: &Resource, ranges: I) {}
    unsafe fn invalidate_mapped_ranges<I>(&self, buffer: &Resource, ranges: I) {}

    unsafe fn create_texture(&self, desc: &crate::TextureDescriptor) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn destroy_texture(&self, texture: Resource) {}
    unsafe fn create_texture_view(
        &self,
        texture: &Resource,
        desc: &crate::TextureViewDescriptor,
    ) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn destroy_texture_view(&self, view: Resource) {}
    unsafe fn create_sampler(&self, desc: &crate::SamplerDescriptor) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn destroy_sampler(&self, sampler: Resource) {}

    unsafe fn create_command_encoder(
        &self,
        desc: &crate::CommandEncoderDescriptor<Api>,
    ) -> DeviceResult<Encoder> {
        Ok(Encoder)
    }
    unsafe fn destroy_command_encoder(&self, encoder: Encoder) {}

    unsafe fn create_bind_group_layout(
        &self,
        desc: &crate::BindGroupLayoutDescriptor,
    ) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn destroy_bind_group_layout(&self, bg_layout: Resource) {}
    unsafe fn create_pipeline_layout(
        &self,
        desc: &crate::PipelineLayoutDescriptor<Api>,
    ) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn destroy_pipeline_layout(&self, pipeline_layout: Resource) {}
    unsafe fn create_bind_group(
        &self,
        desc: &crate::BindGroupDescriptor<Api>,
    ) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn destroy_bind_group(&self, group: Resource) {}

    unsafe fn create_shader_module(
        &self,
        desc: &crate::ShaderModuleDescriptor,
        shader: crate::ShaderInput,
    ) -> Result<Resource, crate::ShaderError> {
        Ok(Resource)
    }
    unsafe fn destroy_shader_module(&self, module: Resource) {}
    unsafe fn create_render_pipeline(
        &self,
        desc: &crate::RenderPipelineDescriptor<Api>,
    ) -> Result<Resource, crate::PipelineError> {
        Ok(Resource)
    }
    unsafe fn destroy_render_pipeline(&self, pipeline: Resource) {}
    unsafe fn create_compute_pipeline(
        &self,
        desc: &crate::ComputePipelineDescriptor<Api>,
    ) -> Result<Resource, crate::PipelineError> {
        Ok(Resource)
    }
    unsafe fn destroy_compute_pipeline(&self, pipeline: Resource) {}

    unsafe fn create_query_set(
        &self,
        desc: &wgt::QuerySetDescriptor<crate::Label>,
    ) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn destroy_query_set(&self, set: Resource) {}
    unsafe fn create_fence(&self) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn destroy_fence(&self, fence: Resource) {}
    unsafe fn get_fence_value(&self, fence: &Resource) -> DeviceResult<crate::FenceValue> {
        Ok(0)
    }
    unsafe fn wait(
        &self,
        fence: &Resource,
        value: crate::FenceValue,
        timeout_ms: u32,
    ) -> DeviceResult<bool> {
        Ok(true)
    }

    unsafe fn start_capture(&self) -> bool {
        false
    }
    unsafe fn stop_capture(&self) {}
    unsafe fn create_acceleration_structure(
        &self,
        desc: &crate::AccelerationStructureDescriptor,
    ) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn get_acceleration_structure_build_sizes<'a>(
        &self,
        _desc: &crate::GetAccelerationStructureBuildSizesDescriptor<'a, Api>,
    ) -> crate::AccelerationStructureBuildSizes {
        Default::default()
    }
    unsafe fn get_acceleration_structure_device_address(
        &self,
        _acceleration_structure: &Resource,
    ) -> wgt::BufferAddress {
        Default::default()
    }
    unsafe fn destroy_acceleration_structure(&self, _acceleration_structure: Resource) {}
}

impl crate::CommandEncoder for Encoder {
    type A = Api;

    unsafe fn begin_encoding(&mut self, label: crate::Label) -> DeviceResult<()> {
        Ok(())
    }
    unsafe fn discard_encoding(&mut self) {}
    unsafe fn end_encoding(&mut self) -> DeviceResult<Resource> {
        Ok(Resource)
    }
    unsafe fn reset_all<I>(&mut self, command_buffers: I) {}

    unsafe fn transition_buffers<'a, T>(&mut self, barriers: T)
    where
        T: Iterator<Item = crate::BufferBarrier<'a, Api>>,
    {
    }

    unsafe fn transition_textures<'a, T>(&mut self, barriers: T)
    where
        T: Iterator<Item = crate::TextureBarrier<'a, Api>>,
    {
    }

    unsafe fn clear_buffer(&mut self, buffer: &Resource, range: crate::MemoryRange) {}

    unsafe fn copy_buffer_to_buffer<T>(&mut self, src: &Resource, dst: &Resource, regions: T) {}

    #[cfg(webgl)]
    unsafe fn copy_external_image_to_texture<T>(
        &mut self,
        src: &wgt::ImageCopyExternalImage,
        dst: &Resource,
        dst_premultiplication: bool,
        regions: T,
    ) where
        T: Iterator<Item = crate::TextureCopy>,
    {
    }

    unsafe fn copy_texture_to_texture<T>(
        &mut self,
        src: &Resource,
        src_usage: crate::TextureUses,
        dst: &Resource,
        regions: T,
    ) {
    }

    unsafe fn copy_buffer_to_texture<T>(&mut self, src: &Resource, dst: &Resource, regions: T) {}

    unsafe fn copy_texture_to_buffer<T>(
        &mut self,
        src: &Resource,
        src_usage: crate::TextureUses,
        dst: &Resource,
        regions: T,
    ) {
    }

    unsafe fn begin_query(&mut self, set: &Resource, index: u32) {}
    unsafe fn end_query(&mut self, set: &Resource, index: u32) {}
    unsafe fn write_timestamp(&mut self, set: &Resource, index: u32) {}
    unsafe fn reset_queries(&mut self, set: &Resource, range: Range<u32>) {}
    unsafe fn copy_query_results(
        &mut self,
        set: &Resource,
        range: Range<u32>,
        buffer: &Resource,
        offset: wgt::BufferAddress,
        stride: wgt::BufferSize,
    ) {
    }

    // render

    unsafe fn begin_render_pass(&mut self, desc: &crate::RenderPassDescriptor<Api>) {}
    unsafe fn end_render_pass(&mut self) {}

    unsafe fn set_bind_group(
        &mut self,
        layout: &Resource,
        index: u32,
        group: &Resource,
        dynamic_offsets: &[wgt::DynamicOffset],
    ) {
    }
    unsafe fn set_push_constants(
        &mut self,
        layout: &Resource,
        stages: wgt::ShaderStages,
        offset_bytes: u32,
        data: &[u32],
    ) {
    }

    unsafe fn insert_debug_marker(&mut self, label: &str) {}
    unsafe fn begin_debug_marker(&mut self, group_label: &str) {}
    unsafe fn end_debug_marker(&mut self) {}

    unsafe fn set_render_pipeline(&mut self, pipeline: &Resource) {}

    unsafe fn set_index_buffer<'a>(
        &mut self,
        binding: crate::BufferBinding<'a, Api>,
        format: wgt::IndexFormat,
    ) {
    }
    unsafe fn set_vertex_buffer<'a>(&mut self, index: u32, binding: crate::BufferBinding<'a, Api>) {
    }
    unsafe fn set_viewport(&mut self, rect: &crate::Rect<f32>, depth_range: Range<f32>) {}
    unsafe fn set_scissor_rect(&mut self, rect: &crate::Rect<u32>) {}
    unsafe fn set_stencil_reference(&mut self, value: u32) {}
    unsafe fn set_blend_constants(&mut self, color: &[f32; 4]) {}

    unsafe fn draw(
        &mut self,
        first_vertex: u32,
        vertex_count: u32,
        first_instance: u32,
        instance_count: u32,
    ) {
    }
    unsafe fn draw_indexed(
        &mut self,
        first_index: u32,
        index_count: u32,
        base_vertex: i32,
        first_instance: u32,
        instance_count: u32,
    ) {
    }
    unsafe fn draw_indirect(
        &mut self,
        buffer: &Resource,
        offset: wgt::BufferAddress,
        draw_count: u32,
    ) {
    }
    unsafe fn draw_indexed_indirect(
        &mut self,
        buffer: &Resource,
        offset: wgt::BufferAddress,
        draw_count: u32,
    ) {
    }
    unsafe fn draw_indirect_count(
        &mut self,
        buffer: &Resource,
        offset: wgt::BufferAddress,
        count_buffer: &Resource,
        count_offset: wgt::BufferAddress,
        max_count: u32,
    ) {
    }
    unsafe fn draw_indexed_indirect_count(
        &mut self,
        buffer: &Resource,
        offset: wgt::BufferAddress,
        count_buffer: &Resource,
        count_offset: wgt::BufferAddress,
        max_count: u32,
    ) {
    }

    // compute

    unsafe fn begin_compute_pass(&mut self, desc: &crate::ComputePassDescriptor<Api>) {}
    unsafe fn end_compute_pass(&mut self) {}

    unsafe fn set_compute_pipeline(&mut self, pipeline: &Resource) {}

    unsafe fn dispatch(&mut self, count: [u32; 3]) {}
    unsafe fn dispatch_indirect(&mut self, buffer: &Resource, offset: wgt::BufferAddress) {}

    unsafe fn build_acceleration_structures<'a, T>(
        &mut self,
        _descriptor_count: u32,
        descriptors: T,
    ) where
        Api: 'a,
        T: IntoIterator<Item = crate::BuildAccelerationStructureDescriptor<'a, Api>>,
    {
    }

    unsafe fn place_acceleration_structure_barrier(
        &mut self,
        _barriers: crate::AccelerationStructureBarrier,
    ) {
    }
}