#![allow(dead_code)]

mod buffers;
mod node_bundle;
mod pipeline;

use inox2d::math::camera::Camera;
use inox2d::model::Model;
use inox2d::nodes::node_data::{InoxData, MaskMode};
use inox2d::puppet::Puppet;
use inox2d::render::RenderCtxKind;

use encase::ShaderType;
use glam::{vec3, Mat4, UVec2, Vec2, Vec3};
use inox2d::texture::decode_model_textures;
use tracing::warn;
use wgpu::util::TextureDataOrder;
use wgpu::{util::DeviceExt, *};

use self::node_bundle::{CompositeData, PartData};
use self::{
	buffers::buffers_for_puppet,
	node_bundle::{node_bundles_for_model, NodeBundle},
	pipeline::{InoxPipeline, Uniform},
};

pub struct Renderer {
	setup: InoxPipeline,
	model_texture_binds: Vec<BindGroup>,
	buffers: buffers::InoxBuffers,
	bundles: Vec<node_bundle::NodeBundle>,
	pub camera: Camera,

	viewport: UVec2,
	// Cached, must change when viewport does
	composite_texture: Option<Texture>,
	mask_texture: Option<Texture>,
}

impl Renderer {
	pub fn new(device: &Device, queue: &Queue, texture_format: TextureFormat, model: &Model, viewport: UVec2) -> Self {
		let setup = InoxPipeline::create(device, texture_format);

		let mut model_texture_binds = Vec::new();

		let sampler = device.create_sampler(&SamplerDescriptor {
			min_filter: FilterMode::Linear,
			mag_filter: FilterMode::Linear,
			mipmap_filter: FilterMode::Linear,
			address_mode_u: AddressMode::ClampToBorder,
			address_mode_v: AddressMode::ClampToBorder,
			border_color: Some(SamplerBorderColor::TransparentBlack),
			..SamplerDescriptor::default()
		});

		let shalltexs = decode_model_textures(model.textures.iter());
		for shalltex in &shalltexs {
			let texture_size = wgpu::Extent3d {
				width: shalltex.width(),
				height: shalltex.height(),
				depth_or_array_layers: 1,
			};

			let texture = device.create_texture_with_data(
				queue,
				&wgpu::TextureDescriptor {
					size: texture_size,
					mip_level_count: 1,
					sample_count: 1,
					dimension: wgpu::TextureDimension::D2,
					format: wgpu::TextureFormat::Rgba8Unorm,
					usage: wgpu::TextureUsages::TEXTURE_BINDING,
					label: Some("texture"),
					view_formats: &[],
				},
				TextureDataOrder::LayerMajor,
				shalltex.pixels(),
			);

			let texture_view = texture.create_view(&wgpu::TextureViewDescriptor::default());

			let texture_bind = device.create_bind_group(&wgpu::BindGroupDescriptor {
				layout: &setup.texture_layout,
				entries: &[
					wgpu::BindGroupEntry {
						binding: 0,
						resource: wgpu::BindingResource::TextureView(&texture_view),
					},
					wgpu::BindGroupEntry {
						binding: 1,
						resource: wgpu::BindingResource::Sampler(&sampler),
					},
				],
				label: Some("texture bind group"),
			});
			model_texture_binds.push(texture_bind);
		}

		let buffers = buffers_for_puppet(device, &model.puppet, setup.uniform_alignment_needed);
		let bundles = node_bundles_for_model(device, &setup, &buffers, &model_texture_binds, &model.puppet);

		Self {
			setup,
			buffers,
			bundles,

			model_texture_binds,
			camera: Camera::default(),

			viewport,
			composite_texture: None,
			mask_texture: None,
		}
	}

	pub fn resize(&mut self, viewport: UVec2) {
		self.viewport = viewport;
		self.composite_texture = None;
		self.mask_texture = None;
	}

	#[allow(clippy::too_many_arguments)]
	fn render_part(
		&self,
		puppet: &Puppet,

		view: &TextureView,
		mask_view: &TextureView,
		uniform_group: &BindGroup,

		op: LoadOp<Color>,
		encoder: &mut CommandEncoder,

		PartData(bundle, masks): &PartData,
	) {
		let mut render_pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
			label: Some("Part Render Pass"),
			color_attachments: &[Some(wgpu::RenderPassColorAttachment {
				view,
				resolve_target: None,
				ops: wgpu::Operations {
					load: op,
					store: StoreOp::Store,
				},
			})],
			depth_stencil_attachment: Some(wgpu::RenderPassDepthStencilAttachment {
				view: mask_view,
				depth_ops: None,
				stencil_ops: Some(Operations {
					load: wgpu::LoadOp::Clear(u32::from(!masks.is_empty())),
					store: StoreOp::Store,
				}),
			}),
			timestamp_writes: None,    // todo!(),
			occlusion_query_set: None, // todo!(),
		});

		render_pass.set_vertex_buffer(0, self.buffers.vertex_buffer.slice(..));
		render_pass.set_vertex_buffer(1, self.buffers.uv_buffer.slice(..));
		render_pass.set_vertex_buffer(2, self.buffers.deform_buffer.slice(..));
		render_pass.set_index_buffer(self.buffers.index_buffer.slice(..), wgpu::IndexFormat::Uint16);
		render_pass.set_pipeline(&self.setup.mask_pipeline);

		for mask in masks {
			let node = puppet.nodes.get_node(mask.source).unwrap();
			let part = if let InoxData::Part(part) = &node.data {
				part
			} else {
				todo!()
			};

			render_pass.set_bind_group(1, &self.model_texture_binds[part.tex_albedo.raw()], &[]);
			render_pass.set_bind_group(2, &self.model_texture_binds[part.tex_emissive.raw()], &[]);
			render_pass.set_bind_group(3, &self.model_texture_binds[part.tex_bumpmap.raw()], &[]);

			render_pass.set_bind_group(
				0,
				uniform_group,
				&[(self.setup.uniform_alignment_needed * self.buffers.uniform_index_map[&mask.source]) as u32],
			);

			match mask.mode {
				MaskMode::Mask => {
					render_pass.set_stencil_reference(0);
				}
				MaskMode::Dodge => {
					render_pass.set_stencil_reference(1);
				}
			}

			let node_rinf = &puppet.render_ctx.node_render_ctxs[&mask.source];
			if let RenderCtxKind::Part(pinf) = &node_rinf.kind {
				let range = (pinf.index_offset as u32)..(pinf.index_offset as u32 + pinf.index_len as u32);
				render_pass.draw_indexed(range, 0, 0..1);
			} else {
				warn!(
					"Node mask {:?} is not a part but is trying to get rendered as one",
					mask.source
				);
			}
		}

		render_pass.set_stencil_reference(0);
		render_pass.execute_bundles(std::iter::once(bundle));

		drop(render_pass);
	}

	#[allow(clippy::too_many_arguments)]
	fn render_composite(
		&self,
		puppet: &Puppet,

		view: &TextureView,
		mask_view: &TextureView,
		uniform_group: &BindGroup,

		op: LoadOp<Color>,
		encoder: &mut CommandEncoder,

		composite_view: &TextureView,
		composite_bind: &BindGroup,
		CompositeData(parts, uuid): &CompositeData,
	) {
		for (i, data) in parts.iter().enumerate() {
			self.render_part(
				puppet,
				composite_view,
				mask_view,
				uniform_group,
				if i == 0 {
					LoadOp::Clear(Color::TRANSPARENT)
				} else {
					LoadOp::Load
				},
				encoder,
				data,
			);
		}

		let mut render_pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
			label: Some("Render Pass"),
			color_attachments: &[Some(wgpu::RenderPassColorAttachment {
				view,
				resolve_target: None,
				ops: wgpu::Operations {
					load: op,
					store: StoreOp::Store,
				},
			})],
			depth_stencil_attachment: Some(wgpu::RenderPassDepthStencilAttachment {
				view: mask_view,
				depth_ops: None,
				stencil_ops: None,
			}),
			timestamp_writes: None,    // todo!(),
			occlusion_query_set: None, //todo!(),
		});

		render_pass.set_vertex_buffer(0, self.buffers.vertex_buffer.slice(..));
		render_pass.set_vertex_buffer(1, self.buffers.uv_buffer.slice(..));
		render_pass.set_vertex_buffer(2, self.buffers.deform_buffer.slice(..));
		render_pass.set_index_buffer(self.buffers.index_buffer.slice(..), wgpu::IndexFormat::Uint16);

		let child = puppet.nodes.get_node(*uuid).unwrap();
		let child = if let InoxData::Composite(comp) = &child.data {
			comp
		} else {
			todo!()
		};

		render_pass.set_pipeline(&self.setup.composite_pipelines[&child.draw_state.blend_mode]);

		render_pass.set_bind_group(
			0,
			uniform_group,
			&[(self.setup.uniform_alignment_needed * self.buffers.uniform_index_map[uuid]) as u32],
		);
		render_pass.set_bind_group(1, composite_bind, &[]);
		render_pass.set_bind_group(2, composite_bind, &[]);
		render_pass.set_bind_group(3, composite_bind, &[]);
		render_pass.draw_indexed(0..6, 0, 0..1);

		drop(render_pass);
	}

	/// It is a logical error to pass in a different puppet than the one passed to create.
	pub fn render(&mut self, queue: &Queue, device: &Device, puppet: &Puppet, view: &TextureView) {
		let uniform_group = device.create_bind_group(&wgpu::BindGroupDescriptor {
			label: Some("inox2d uniform bind group"),
			layout: &self.setup.uniform_layout,
			entries: &[wgpu::BindGroupEntry {
				binding: 1,
				resource: wgpu::BindingResource::Buffer(wgpu::BufferBinding {
					buffer: &self.buffers.uniform_buffer,
					offset: 0,
					size: wgpu::BufferSize::new(Uniform::min_size().into()),
				}),
			}],
		});

		let composite_texture = self.composite_texture.get_or_insert_with(|| {
			device.create_texture(&wgpu::TextureDescriptor {
				size: wgpu::Extent3d {
					width: self.viewport.x,
					height: self.viewport.y,
					depth_or_array_layers: 1,
				},
				mip_level_count: 1,
				sample_count: 1,
				dimension: wgpu::TextureDimension::D2,
				format: wgpu::TextureFormat::Bgra8Unorm,
				usage: wgpu::TextureUsages::TEXTURE_BINDING | wgpu::TextureUsages::RENDER_ATTACHMENT,
				label: Some("texture"),
				view_formats: &[],
			})
		});

		let composite_view = composite_texture.create_view(&wgpu::TextureViewDescriptor::default());

		let mask_texture = self.mask_texture.get_or_insert_with(|| {
			device.create_texture(&wgpu::TextureDescriptor {
				size: wgpu::Extent3d {
					width: self.viewport.x,
					height: self.viewport.y,
					depth_or_array_layers: 1,
				},
				mip_level_count: 1,
				sample_count: 1,
				dimension: wgpu::TextureDimension::D2,
				format: wgpu::TextureFormat::Depth24PlusStencil8,
				usage: wgpu::TextureUsages::TEXTURE_BINDING | wgpu::TextureUsages::RENDER_ATTACHMENT,
				label: Some("texture"),
				view_formats: &[],
			})
		});

		let mask_view = mask_texture.create_view(&wgpu::TextureViewDescriptor::default());

		let sampler = device.create_sampler(&SamplerDescriptor {
			min_filter: FilterMode::Linear,
			mag_filter: FilterMode::Linear,
			mipmap_filter: FilterMode::Linear,
			address_mode_u: AddressMode::ClampToBorder,
			address_mode_v: AddressMode::ClampToBorder,
			border_color: Some(SamplerBorderColor::TransparentBlack),
			..SamplerDescriptor::default()
		});

		let composite_bind = device.create_bind_group(&wgpu::BindGroupDescriptor {
			layout: &self.setup.texture_layout,
			entries: &[
				wgpu::BindGroupEntry {
					binding: 0,
					resource: wgpu::BindingResource::TextureView(&composite_view),
				},
				wgpu::BindGroupEntry {
					binding: 1,
					resource: wgpu::BindingResource::Sampler(&sampler),
				},
			],
			label: Some("texture bind group"),
		});

		for uuid in puppet.nodes.all_node_ids() {
			let node = puppet.nodes.get_node(uuid).unwrap();

			let unif = match &node.data {
				InoxData::Part(_) => {
					let mvp = Mat4::from_scale(vec3(1.0, 1.0, 0.0))
						* self.camera.matrix(self.viewport.as_vec2())
						* puppet.render_ctx.node_render_ctxs[&uuid].trans;

					Uniform {
						opacity: 1.0,
						mult_color: Vec3::ONE,
						screen_color: Vec3::ZERO,
						emission_strength: 0.0,
						offset: Vec2::ZERO,
						mvp,
					}
				}
				InoxData::Composite(_) => Uniform {
					opacity: 1.0,
					mult_color: Vec3::ONE,
					screen_color: Vec3::ZERO,
					emission_strength: 0.0,
					offset: Vec2::ZERO,
					mvp: Mat4::IDENTITY,
				},
				_ => continue,
			};

			let offset = self.setup.uniform_alignment_needed * self.buffers.uniform_index_map[&uuid];

			let mut buffer = encase::UniformBuffer::new(Vec::new());
			buffer.write(&unif).unwrap();
			queue.write_buffer(&self.buffers.uniform_buffer, offset as u64, buffer.as_ref());
		}

		// Upload deform buffers
		let mut buffer = encase::DynamicStorageBuffer::new(Vec::new());
		(buffer.write(&puppet.render_ctx.vertex_buffers.deforms)).unwrap();
		queue.write_buffer(&self.buffers.deform_buffer, 0, buffer.as_ref());

		let mut first = true;

		let mut encoder = device.create_command_encoder(&wgpu::CommandEncoderDescriptor {
			label: Some("Part Render Encoder"),
		});

		for bundle in &self.bundles {
			let op = if first {
				first = false;

				wgpu::LoadOp::Clear(wgpu::Color::TRANSPARENT)
			} else {
				wgpu::LoadOp::Load
			};

			match bundle {
				NodeBundle::Part(data) => {
					self.render_part(puppet, view, &mask_view, &uniform_group, op, &mut encoder, data);
				}
				NodeBundle::Composite(data) => {
					self.render_composite(
						puppet,
						view,
						&mask_view,
						&uniform_group,
						op,
						&mut encoder,
						&composite_view,
						&composite_bind,
						data,
					);
				}
			}
		}
		queue.submit(std::iter::once(encoder.finish()));
	}
}