package gitea

import (
	"crypto/tls"
	"encoding/base64"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"model-repository/domain"
	"net/http"
	"regexp"
	"strconv"
	"time"

	"github.com/go-resty/resty/v2"
	"gopkg.in/yaml.v2"
)

const (
	DEFALUT_REVISION  = "main"
	TIME_FORMAT       = "2006-01-02T15:04:05.000Z"
	REF_VERSION_LIMIT = 20
)

var (
	TagList = []string{
		"audio-classification",
		"automatic-speech-recognition",
		"conversational",
		"depth-estimation",
		"document-question-answering",
		"feature-extraction",
		"fill-mask",
		"image-classification",
		"image-feature-extraction",
		"image-segmentation",
		"image-to-image",
		"image-to-text",
		"mask-generation",
		"ner",
		"object-detection",
		"question-answering",
		"sentiment-analysis",
		"summarization",
		"table-question-answering",
		"text-classification",
		"text-generation",
		"text-to-audio",
		"text-to-speech",
		"text2text-generation",
		"token-classification",
		"translation",
		"video-classification",
		"visual-question-answering",
		"vqa",
		"zero-shot-audio-classification",
		"zero-shot-classification",
		"zero-shot-image-classification",
		"zero-shot-object-detection",
		"translation_XX_to_YY",
	}
)

type GiteaStorage struct {
	client *resty.Client
}

func NewGiteaStorage(baseUrl string) *GiteaStorage {
	client := resty.New().SetTLSClientConfig(&tls.Config{InsecureSkipVerify: true}).SetBaseURL(baseUrl).SetTimeout(5 * time.Minute)
	return &GiteaStorage{
		client: client,
	}
}

func (gs *GiteaStorage) GetPipelineTag(hfModel *domain.HuggingFaceModelRequest) (*Metadata, error) {
	url := fmt.Sprintf("/api/v1/repos/%s/%s/raw/README.md", hfModel.Project, hfModel.Name)
	resp, err := gs.client.R().
		SetHeader("Accept", "application/json").
		SetHeader("access_token", hfModel.AccessToken).
		SetQueryParams(map[string]string{
			"ref": safeSubstring(hfModel.Version, REF_VERSION_LIMIT),
		}).
		Get(url)
	if err != nil {
		return nil, err
	}
	var metadata Metadata
	err = yaml.Unmarshal(resp.Body(), &metadata)
	if err != nil {
		fmt.Println("Error parsing YAML:", err)
		return nil, err
	}
	return &metadata, nil
}

func (gs *GiteaStorage) GetModelInfo(hfModel *domain.HuggingFaceModelRequest) (*domain.HuggingFaceModelInfo, error) {
	url := ""
	mir := &ModelInfoResp{}
	hfmi := &domain.HuggingFaceModelInfo{}

	if hfModel.Version == "" {
		url = fmt.Sprintf("/api/v1/repos/%s/%s/git/trees/%s", hfModel.Project, hfModel.Name, DEFALUT_REVISION)
	} else {
		url = fmt.Sprintf("/api/v1/repos/%s/%s/git/trees/%s", hfModel.Project, hfModel.Name, hfModel.Version)
	}
	resp, err := gs.client.R().
		SetHeader("Accept", "application/json").
		SetHeader("access_token", hfModel.AccessToken).
		SetQueryParams(map[string]string{
			"recursive": "true",
		}).
		SetResult(mir).
		Get(url)
	defer resp.RawBody().Close()

	if err != nil {
		return nil, err
	}
	if resp.StatusCode() == 404 {
		return nil, fmt.Errorf(domain.HUGGINGFACE_HEADER_X_Error_Code_REPO_NotFound)
	}
	for _, file := range mir.Tree {
		hfmi.Siblings = append(hfmi.Siblings, domain.Sibling{Rfilename: file.Path})
	}
	hfmi.LastModified = time.Now().Format(TIME_FORMAT)
	hfmi.CreatedAt = time.Now().Format(TIME_FORMAT)
	hfmi.ModelInfoID = hfModel.Project + "/" + hfModel.Name
	hfmi.ModelID = hfModel.Project + "/" + hfModel.Name
	hfmi.SHA = mir.SHA
	hfmi.LibraryName = "transformers"
	readmeMeta, err := gs.GetPipelineTag(hfModel)
	if err != nil {
		return nil, err
	}
	hfmi.Tags = readmeMeta.Tags
	if readmeMeta.PipLinetag == "" {
		for _, rtag := range readmeMeta.Tags {
			for _, tag := range TagList {
				if rtag == tag {
					hfmi.PipelineTag = tag
					break
				}
			}
		}
	} else {
		hfmi.PipelineTag = readmeMeta.PipLinetag
	}
	return hfmi, nil
}

func (gs *GiteaStorage) GetModelFileTree(hfModel *domain.HuggingFaceModelRequest) ([]domain.HuggingFaceModelFileInfo, error) {
	url := ""
	mir := &ModelInfoResp{}
	var tree []domain.HuggingFaceModelFileInfo

	if hfModel.Version == "" {
		url = fmt.Sprintf("/api/v1/repos/%s/%s/git/trees/%s", hfModel.Project, hfModel.Name, DEFALUT_REVISION)
	} else {
		url = fmt.Sprintf("/api/v1/repos/%s/%s/git/trees/%s", hfModel.Project, hfModel.Name, hfModel.Version)
	}
	resp, err := gs.client.R().
		SetHeader("Accept", "application/json").
		SetHeader("access_token", hfModel.AccessToken).
		SetQueryParams(map[string]string{
			"recursive": "true",
		}).
		SetResult(mir).
		Get(url)
	if err != nil {
		return nil, err
	}
	defer resp.RawBody().Close()
	for _, file := range mir.Tree {
		if domain.IsLfsFile(file.Path) {
			content, err := gs.GetFileContent(&domain.HuggingFaceFileRequest{
				Project:     hfModel.Project,
				Name:        hfModel.Name,
				File:        file.Path,
				Version:     hfModel.Version,
				AccessToken: hfModel.AccessToken,
			})
			if err != nil {
				return nil, err
			}
			size, hash := gs.ExtractLfsMetadata(content)
			tree = append(tree, domain.HuggingFaceModelFileInfo{
				Type: string(file.Type),
				Oid:  file.SHA,
				Size: size,
				Path: file.Path,
				Lfs: &domain.HuggingFaceModelLfsFileInfo{
					Oid:         hash,
					Size:        size,
					PointerSize: file.Size,
				},
			})
		} else {
			tree = append(tree, domain.HuggingFaceModelFileInfo{
				Type: string(file.Type),
				Oid:  file.SHA,
				Size: file.Size,
				Path: file.Path,
			})
		}
	}
	return tree, nil
}

func (gs *GiteaStorage) GetFileContent(hfi *domain.HuggingFaceFileRequest) (string, error) {
	url := fmt.Sprintf("/api/v1/repos/%s/%s/raw/%s", hfi.Project, hfi.Name, hfi.File)
	resp, err := gs.client.R().
		SetHeader("access_token", hfi.AccessToken).
		SetQueryParams(map[string]string{
			"ref": safeSubstring(hfi.Version, REF_VERSION_LIMIT),
		}).
		Get(url)
	if err != nil {
		return "", err
	}
	return string(resp.Body()), nil
}

func (gs *GiteaStorage) GetFileMetadata(hfFile *domain.HuggingFaceFileRequest) (*domain.GitFileMetadata, error) {
	// TODO Implement me
	gfd := &domain.GitFileMetadata{}
	metaresp := &FileMetaResp{}
	url := fmt.Sprintf("/api/v1/repos/%s/%s/contents/%s", hfFile.Project, hfFile.Name, hfFile.File)
	resp, err := gs.client.R().
		SetHeader("Accept", "application/json").
		SetHeader("access_token", hfFile.AccessToken).
		SetQueryParams(map[string]string{
			// 支持commitId(前10位)，branch，tag
			"ref": safeSubstring(hfFile.Version, REF_VERSION_LIMIT),
		}).
		SetResult(metaresp).
		Get(url)
	if err != nil {
		return nil, err
	}
	defer resp.RawBody().Close()

	if domain.IsLfsFile(hfFile.File) {
		decodeContent, err := base64.StdEncoding.DecodeString(metaresp.Content)
		if err != nil {
			return nil, err
		}
		match := Regexp(`size (\d+)`, string(decodeContent))
		if len(match) < 2 {
			return nil, errors.New("size not found")
		}
		size, err := strconv.Atoi(match[1])
		if err != nil {
			return nil, err
		}
		sha256 := Regexp("sha256:([a-f0-9]+)", string(decodeContent))
		gfd.Size = int64(size)
		gfd.SHA256 = sha256[1]

	} else {
		gfd.Size = int64(metaresp.Size)
	}
	gfd.LastCommitID = metaresp.LastCommitSHA
	gfd.BlobID = metaresp.SHA
	gfd.FileName = metaresp.Name
	return gfd, nil

}

func safeSubstring(s string, n int) string {
	runes := []rune(s)
	if len(runes) > n {
		return string(runes[:n])
	}
	return s
}

func (gs *GiteaStorage) ExtractLfsMetadata(content string) (int64, string) {
	match := Regexp(`size (\d+)`, content)
	if len(match) < 2 {
		return 0, ""
	}
	size, err := strconv.Atoi(match[1])
	if err != nil {
		return 0, ""
	}
	sha256 := Regexp("sha256:([a-f0-9]+)", content)
	return int64(size), sha256[1]
}

func (gs *GiteaStorage) GetLfsRawFile(hfFile *domain.HuggingFaceFileRequest, writer io.Writer) error {
	url := fmt.Sprintf("/api/v1/repos/%s/%s/media/%s", hfFile.Project, hfFile.Name, hfFile.File)
	resp, _ := gs.client.R().SetDoNotParseResponse(true).
		SetHeader("Accept", "application/json").
		SetHeader("access_token", hfFile.AccessToken).
		SetQueryParams(map[string]string{
			"ref": safeSubstring(hfFile.Version, REF_VERSION_LIMIT),
		}).
		Get(url)
	defer resp.RawBody().Close() // 确保关闭流

	// 使用 buffer 进行流式读写，提高性能
	buffer := make([]byte, 4096*1024) // 4M buffer
	_, err := io.CopyBuffer(writer, resp.RawBody(), buffer)
	return err
}

func (gs *GiteaStorage) CreateRepo(repo *domain.CreateRepoInput, token string) (*domain.CreateRepoOutput, error) {
	url := fmt.Sprintf("/api/v1/user/repos")

	// 构建请求体
	requestBody := map[string]interface{}{
		"auto_init":      false,
		"default_branch": DEFALUT_REVISION,
		"name":           repo.Name,
		"private":        true,
		"template":       false,
		"trust_model":    "default",
	}
	requestBodyBytes, _ := json.Marshal(requestBody)

	resp, err := gs.client.R().
		SetHeader("Authorization", fmt.Sprintf("token %s", token)).
		SetHeader("Content-Type", "application/json").
		SetBody(requestBodyBytes).
		Post(url)

	if err != nil {
		return nil, err
	}
	defer resp.RawBody().Close() // 确保关闭流

	if resp.StatusCode() == http.StatusConflict {
		output := &domain.CreateRepoOutput{
			URL: domain.HUGGINGFACE_ENDPOINT + "/" + repo.Organization + "/" + repo.Name,
		}
		return output, fmt.Errorf(domain.HUGGINGFACE_HEADER_X_Error_Code_REPO_EXIST)
	}

	if resp.StatusCode() != http.StatusCreated {
		return nil, fmt.Errorf("failed to create repository, status code: %d", resp.StatusCode())
	}
	// 解析响应体
	var responseMap map[string]interface{}
	if err := json.Unmarshal(resp.Body(), &responseMap); err != nil {
		return nil, fmt.Errorf("failed to parse response body: %w", err)
	}

	// 提取 id 字段
	id, ok := responseMap["id"].(float64)
	if !ok {
		return nil, fmt.Errorf("id field not found or not a float64 in response")
	}
	output := &domain.CreateRepoOutput{
		URL:  domain.HUGGINGFACE_ENDPOINT + "/" + repo.Organization + "/" + repo.Name,
		Name: repo.Organization + "/" + repo.Name,
		//从 resp id中获取
		ID: fmt.Sprintf("%f", id),
	}
	return output, nil
}

func Regexp(reg string, input string) []string {
	re := regexp.MustCompile(reg)
	return re.FindStringSubmatch(input)
}

type FileMetaResp struct {
	Name            string `json:"name"`
	Path            string `json:"path"`
	SHA             string `json:"sha"`
	LastCommitSHA   string `json:"last_commit_sha"`
	Type            string `json:"type"`
	Size            int64  `json:"size"`
	Encoding        string `json:"encoding"`
	Content         string `json:"content"`
	Target          string `json:"target"`
	URL             string `json:"url"`
	HTMLURL         string `json:"html_url"`
	GitURL          string `json:"git_url"`
	DownloadURL     string `json:"download_url"`
	SubmoduleGitURL string `json:"submodule_git_url"`
	Links           Links  `json:"_links"`
}

type Links struct {
	Self string `json:"self"`
	Git  string `json:"git"`
	HTML string `json:"html"`
}

type ModelInfoResp struct {
	SHA        string `json:"sha"`
	URL        string `json:"url"`
	Tree       []Tree `json:"tree"`
	Truncated  bool   `json:"truncated"`
	Page       int64  `json:"page"`
	TotalCount int64  `json:"total_count"`
}

type Tree struct {
	Path string `json:"path"`
	Mode string `json:"mode"`
	Type Type   `json:"type"`
	Size int64  `json:"size"`
	SHA  string `json:"sha"`
	URL  string `json:"url"`
}

type Type string

const (
	Blob Type = "blob"
)

type Metadata struct {
	License     string   `yaml:"license"`
	LicenseName string   `yaml:"license_name"`
	LicenseLink string   `yaml:"license_link"`
	Tags        []string `yaml:"tags"`
	Datasets    []string `yaml:"datasets"`
	PipLinetag  string   `yaml:"pipeline_tag"`
	Language    []string `yaml:"language"`
}