package exporter

import (
	"errors"
	"fmt"
	_ "image/png"
	"os"
	"path"
	"path/filepath"
	"strings"

	_ "github.com/ftrvxmtrx/tga"
	"github.com/qmuntal/gltf"

	"git.influ.su/artmares/digglestool/internal/pkg/logger"
	"git.influ.su/artmares/digglestool/pkg/threedb"
)

type Exporter struct {
	onlyBaseMesh     bool
	animation        bool
	texturesBasePath *string
	cache            *Cache[*CacheItem]
}

type Option func(*Exporter)

func WithOnlyBaseMesh() Option {
	return func(e *Exporter) {
		e.onlyBaseMesh = true
	}
}

func WithTexturesBasePath(basePath string) Option {
	return func(e *Exporter) {
		if basePath != "" {
			e.texturesBasePath = &basePath
		}
	}
}

func WithAnimation() Option {
	return func(e *Exporter) {
		e.animation = true
	}
}

func NewExporter(options ...Option) *Exporter {
	e := &Exporter{
		cache: NewCache[*CacheItem](),
	}
	for _, option := range options {
		option(e)
	}
	return e
}

func (e *Exporter) Export(basePath string, model *threedb.Model) error {
	if model == nil {
		return errors.New("model is nil")
	}
	meshesLen := len(model.Meshes)
	if meshesLen == 0 {
		return errors.New("no meshes to export")
	}
	if err := e.prepareTextures(); err != nil {
		return err
	}
	if e.onlyBaseMesh {
		logger.Infof("Export Base Model: %s", model.Name)
		doc, err := e.generate(model, 0)
		if err != nil {
			return err
		}
		if err = gltf.Save(doc, path.Join(basePath, fmt.Sprintf("%s-base-model.gltf", model.Name))); err != nil {
			return err
		}
	}
	if e.animation {
		dirPath := path.Join(basePath, "animation", model.Name)
		if _, err := os.Stat(dirPath); os.IsNotExist(err) {
			if err = os.MkdirAll(dirPath, os.ModeDir); err != nil {
				return err
			}
		}
		logger.Infof("Export Animation to %s", dirPath)
		length := len(model.Animations)
		for index, animation := range model.Animations {
			logger.Infof("Export progress: %d/%d\r", index+1, length)
			indexes := make([]int, len(animation.MeshIndexes))
			for _, index := range animation.MeshIndexes {
				indexes = append(indexes, int(index))
			}
			doc, err := e.generate(model, indexes...)
			if err != nil {
				return err
			}
			if err = gltf.Save(doc, path.Join(dirPath, fmt.Sprintf("%s-%s.gltf", model.Name, animation.Name))); err != nil {
				return err
			}
		}
	}

	return nil
}

func (e *Exporter) generate(model *threedb.Model, meshIndexes ...int) (*gltf.Document, error) {
	return new(Model).Generate(model, e.cache, meshIndexes...)
	//var err error
	//doc := gltf.NewDocument()
	//log.Println("Generate", meshIndexes)
	//materialsMap := make(map[uint16]int)
	//for _, meshIndex := range meshIndexes {
	//	mesh := model.Meshes[meshIndex]
	//	var nodeIndexes []int
	//	for index, meshLink := range mesh.Links {
	//		points := model.Points[meshLink.Points]
	//		var vertices [][3]float32
	//		for _, point := range points {
	//			vec := point.Transform(100)
	//			vec = vec.Normalize()
	//			vertices = append(vertices, vec)
	//		}
	//		verticesIndex := modeler.WriteAccessor(doc, gltf.TargetElementArrayBuffer, vertices)
	//		textureCoordinates := model.TextureCoordinates[meshLink.TextureCoordinates]
	//		var textureCoord [][2]float32
	//		for _, txc := range textureCoordinates {
	//			textureCoord = append(textureCoord, txc)
	//		}
	//		textureCoordIndex := modeler.WriteAccessor(doc, gltf.TargetArrayBuffer, textureCoord)
	//		trianglesIndex := modeler.WriteAccessor(doc, gltf.TargetArrayBuffer, model.Triangles[meshLink.Triangles])
	//		materialIndex, ok := materialsMap[meshLink.Material]
	//		if !ok {
	//			material := model.Materials[meshLink.Material]
	//			log.Println("Material", material.Name)
	//			data := e.cache.Bytes(material.Name)
	//			if data == nil {
	//				var f *os.File
	//				if f, err = os.Open(e.cache.Path(material.Name)); err != nil {
	//					return nil, err
	//				}
	//				img, _, err := image.Decode(f)
	//				if err != nil {
	//					return nil, err
	//				}
	//				buff, putter := helpers.NewBuffer()
	//				if err = png.Encode(buff, img); err != nil {
	//					return nil, err
	//				}
	//				data = buff.Bytes()
	//				log.Println(material.Name, len(data))
	//				putter(buff)
	//				e.cache.AddBytes(material.Name, data)
	//			}
	//			log.Println(material.Name, len(data))
	//			var imageIndex int
	//			if imageIndex, err = modeler.WriteImage(doc, material.Name, "image/png", bytes.NewBuffer(data)); err != nil {
	//				return nil, err
	//			}
	//			doc.Textures = append(doc.Textures, &gltf.Texture{
	//				Name:    material.Name,
	//				Sampler: gltf.Index(0),
	//				Source:  gltf.Index(imageIndex),
	//			})
	//			materialIndex = len(doc.Materials)
	//			doc.Materials = append(doc.Materials, &gltf.Material{
	//				Name:        material.Name,
	//				AlphaMode:   gltf.AlphaOpaque,
	//				AlphaCutoff: gltf.Float(0.5),
	//				PBRMetallicRoughness: &gltf.PBRMetallicRoughness{
	//					BaseColorTexture: &gltf.TextureInfo{Index: imageIndex},
	//					BaseColorFactor:  &[4]float64{0.8, 0.8, 0.8, 1},
	//					MetallicFactor:   gltf.Float(0.1),
	//					RoughnessFactor:  gltf.Float(0.99),
	//				},
	//			})
	//			materialsMap[meshLink.Material] = materialIndex
	//		}
	//		log.Println("materialIndex", materialIndex)
	//		doc.Meshes = append(doc.Meshes, &gltf.Mesh{
	//			Name: fmt.Sprintf("%s-%d", model.Name, index),
	//			Primitives: []*gltf.Primitive{{
	//				Attributes: gltf.PrimitiveAttributes{
	//					gltf.POSITION:   verticesIndex,
	//					gltf.TEXCOORD_0: textureCoordIndex,
	//				},
	//				Indices:  gltf.Index(trianglesIndex),
	//				Material: gltf.Index(materialIndex),
	//			}},
	//		})
	//		nodeIndexes = append(nodeIndexes, len(doc.Nodes))
	//		doc.Nodes = append(doc.Nodes, &gltf.Node{
	//			Mesh: gltf.Index(len(doc.Meshes) - 1),
	//		})
	//	}
	//	doc.Scenes = []*gltf.Scene{{
	//		Name:  "Root Scene",
	//		Nodes: nodeIndexes,
	//	}}
	//	doc.Samplers = []*gltf.Sampler{{}}
	//}
	//return doc, nil
}

func (e *Exporter) prepareTextures() error {
	if e.texturesBasePath == nil {
		return nil
	}
	if err := filepath.Walk(*e.texturesBasePath, func(pathFile string, info os.FileInfo, err error) error {
		if err != nil {
			return err
		}
		if strings.HasSuffix(info.Name(), ".tga") {
			key := strings.TrimSuffix(info.Name(), ".tga")
			item, ok := e.cache.Get(key)
			if !ok {
				item = &CacheItem{}
			}
			if info.Size() > item.Size {
				item.Path = pathFile
			}
			e.cache.Set(key, item)
		}
		return nil
	}); err != nil {
		return err
	}
	return nil
}