refactor: 模块化重构并优化输出

- 将原本的 main.go 拆分为 命令 网络请求 下载三个单独职责的文件
- 优化输出, 添加用户友好的Emoji

4 files changed, 277 insertions, 221 deletions

diff --git a/cmd/bvd/main.go b/cmd/bvd/main.go
new file mode 100644
index 0000000..3a537b4
--- /dev/null
+++ b/cmd/bvd/main.go
@@ -0,0 +1,42 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+
+	"bvd/internal/api"
+	downloader "bvd/internal/download"
+
+	"github.com/urfave/cli/v2"
+)
+
+func main() {
+	app := &cli.App{
+		Name:  "bvd",
+		Usage: "快速、高效、易用的下载B站视频 CLI 工具",
+		Commands: []*cli.Command{
+			{
+				Name:  "download",
+				Usage: "下载指定 BV 号的视频",
+				Action: func(c *cli.Context) error {
+					bvid := c.Args().First()
+					if bvid == "" {
+						return fmt.Errorf("请提供视频 BV 号")
+					}
+
+					biliAPI := api.NewBiliAPI()
+					downloader := downloader.NewDownloader()
+
+					return downloader.Start(bvid, biliAPI)
+				},
+				ArgsUsage: "<BVID> 欲下载视频的 BV 号",
+			},
+		},
+		Version: "1.0.1",
+	}
+
+	if err := app.Run(os.Args); err != nil {
+		log.Fatal(err)
+	}
+}
diff --git a/internal/api/biliapi.go b/internal/api/biliapi.go
new file mode 100644
index 0000000..efd2499
--- /dev/null
+++ b/internal/api/biliapi.go
@@ -0,0 +1,94 @@
+package api
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"time"
+)
+
+type VideoBaseInfo struct {
+	Data []struct {
+		Cid        int    `json:"cid"`         // 每一个视频的 CID
+		Part       string `json:"part"`        // 分 P 标题
+		Page       int    `json:"page"`        // 分 P 编号
+		FirstFrame string `json:"first_frame"` // 封面图
+	} `json:"data"`
+}
+
+type BiliAPI struct {
+	Client *http.Client
+}
+
+func NewBiliAPI() *BiliAPI {
+	return &BiliAPI{
+		Client: &http.Client{Timeout: 30 * time.Second},
+	}
+}
+
+// func getInfo(bvid string) (VideoBaseInfo, error) {
+// 	var APIUrl string = "https://api.bilibili.com/x/player/pagelist?bvid="
+// 	APIUrl += bvid
+// 	client := &http.Client{
+// 		Timeout: 30 * time.Second,
+// 	}
+
+// 	// 发送 GET 请求
+// 	resp, err := client.Get(APIUrl)
+// 	if err != nil {
+// 		return VideoBaseInfo{}, fmt.Errorf("发送请求失败: %w", err)
+// 	}
+// 	defer resp.Body.Close()
+
+// 	body, err := io.ReadAll(resp.Body)
+// 	if err != nil {
+// 		return VideoBaseInfo{}, fmt.Errorf("读取响应失败: %w", err)
+// 	}
+
+// 	var result VideoBaseInfo
+// 	if err := json.Unmarshal(body, &result); err != nil {
+// 		return VideoBaseInfo{}, fmt.Errorf("JSON 解析失败： %w", err)
+// 	}
+
+// 	return VideoBaseInfo{}, err
+// }
+
+func (a *BiliAPI) GetVideoInfo(bvid string) (*VideoBaseInfo, error) {
+	var APIUrl string = "https://api.bilibili.com/x/player/pagelist?bvid="
+	APIUrl += bvid
+	client := a.Client
+	if client == nil {
+		client = &http.Client{
+			Timeout: 30 * time.Second,
+		}
+	}
+
+	// 发送 GET 请求
+	resp, err := client.Get(APIUrl)
+	if err != nil {
+		return &VideoBaseInfo{}, fmt.Errorf("❌ 发送请求失败: %w", err)
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return &VideoBaseInfo{}, fmt.Errorf("❌ 读取响应失败: %w", err)
+	}
+
+	if len(body) > 0 && body[0] == '<' {
+		snippet := string(body)
+		if len(snippet) > 512 {
+			snippet = snippet[:512]
+		}
+		return nil, fmt.Errorf("❌ 服务器返回 HTML 而非 JSON: %s", snippet)
+	}
+
+	var result VideoBaseInfo
+	if err := json.Unmarshal(body, &result); err != nil {
+		return &VideoBaseInfo{}, fmt.Errorf("❌ JSON 解析失败： %w", err)
+	}
+
+	return &result, nil
+
+}
diff --git a/internal/download/downloader.go b/internal/download/downloader.go
new file mode 100644
index 0000000..24a91db
--- /dev/null
+++ b/internal/download/downloader.go
@@ -0,0 +1,141 @@
+package downloader
+
+import (
+	"bvd/internal/api"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path/filepath"
+)
+
+type Downloader struct{}
+
+func NewDownloader() *Downloader {
+	return &Downloader{}
+}
+
+func requestSend(urls []string, video *api.VideoBaseInfo) error {
+	downloadDir := "./downloads/"
+	if err := os.MkdirAll(downloadDir, 0755); err != nil {
+		return fmt.Errorf("❌ 创建下载目录失败：%w", err)
+	}
+
+	for i := 0; i < len(urls); i++ {
+		fmt.Printf("✅ 开始下载第 %d 个文件\n", i+1)
+
+		// 创建支持重定向的 HTTP 客户端
+		client := &http.Client{
+			CheckRedirect: func(req *http.Request, via []*http.Request) error {
+				return nil
+			},
+		}
+
+		req, err := http.NewRequest("GET", urls[i], nil)
+		if err != nil {
+			return err
+		}
+
+		req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36")
+		req.Header.Set("referer", "https://www.bilibili.com")
+
+		// 发送请求
+		resp, err := client.Do(req)
+		if err != nil {
+			return fmt.Errorf("❌ HTTP请求失败：%w", err)
+		}
+		defer resp.Body.Close()
+
+		// 检查响应状态
+		if resp.StatusCode != http.StatusOK {
+			return fmt.Errorf("❌ 服务器返回错误状态码: %d", resp.StatusCode)
+		}
+
+		// 构建文件名
+		filename := filepath.Join(downloadDir, video.Data[i].Part+".mp4")
+		fmt.Printf("✅ 保存到: %s\n", filename)
+
+		// 创建文件
+		out, err := os.Create(filename)
+		if err != nil {
+			return fmt.Errorf("❌ 创建文件失败：%w", err)
+		}
+
+		// 下载文件
+		_, err = io.Copy(out, resp.Body)
+		if err != nil {
+			out.Close()
+			return fmt.Errorf("❌ 下载失败：%w", err)
+		}
+
+		// 关闭文件
+		if err := out.Close(); err != nil {
+			return fmt.Errorf("❌ 关闭文件失败：%w", err)
+		}
+
+		fmt.Printf("✅ 文件下载成功: %s\n", filename)
+
+	}
+
+	return nil
+}
+
+func (d *Downloader) Start(bvid string, apiClient *api.BiliAPI) error {
+	fmt.Println("✅ 获取到 BV 号:", bvid)
+
+	videoInfo, err := apiClient.GetVideoInfo(bvid)
+	if err != nil {
+		return err
+	}
+
+	// 2. 提取 提取所有 CID
+	cids := make([]int, len(videoInfo.Data))
+	for i, page := range videoInfo.Data {
+		cids[i] = page.Cid
+	}
+
+	fmt.Println("✅ 获取到 CID 列表", cids)
+
+	// 3. 为每个CID获取下载链接
+	downloadUrls := make([]string, len(cids))
+
+	for j, cid := range cids {
+		apiUrl := fmt.Sprintf("https://api.bilibili.com/x/player/playurl?&cid=%d&bvid=%s&qn=80", cid, bvid)
+
+		resp, err := apiClient.Client.Get(apiUrl)
+		if err != nil {
+			return fmt.Errorf("❌ CID %d 请求 请求失败: %w", cid, err)
+		}
+
+		body, err := io.ReadAll(resp.Body)
+		resp.Body.Close()
+		if err != nil {
+			return fmt.Errorf("❌ CID %d 读取响应失败: %w", cid, err)
+		}
+
+		var result struct {
+			Data struct {
+				Durl []struct {
+					Url string `json:"url"`
+				} `json:"durl"`
+			} `json:"data"`
+		}
+
+		if err := json.Unmarshal(body, &result); err != nil {
+			return fmt.Errorf("❌ CID %d JSON解析失败: %w", cid, err)
+		}
+
+		if len(result.Data.Durl) == 0 {
+			return fmt.Errorf("❌ CID %d 没有 没有获取到下载链接", cid)
+		}
+
+		downloadUrls[j] = result.Data.Durl[0].Url
+	}
+
+	fmt.Println("✅ 获取到所有下载链接")
+
+	requestSend(downloadUrls, videoInfo)
+
+	return nil
+}
diff --git a/main.go b/main.go
deleted file mode 100644
index 4c296f3..0000000
--- a/main.go
+++ /dev/null
@@ -1,221 +0,0 @@
-package main
-
-import (
-	"encoding/json"
-	"fmt"
-	"github.com/urfave/cli/v2"
-	"io"
-	"log"
-	"net/http"
-	"os"
-	"path/filepath"
-	"time"
-)
-
-const AppVersion = "0.1.0"
-
-type VideoBaseInfo struct {
-	Data []struct {
-		Cid        int    `json:"cid"`         // 每一个视频的 CID
-		Part       string `json:"part"`        // 分 P 标题
-		Page       int    `json:"page"`        // 分 P 编号
-		FirstFrame string `json:"first_frame"` // 封面图
-	} `json:"data"`
-}
-
-// getDownloadUrl函数得到的JSON的匹配结构体
-type getDownloadUrlJson struct {
-	Data struct {
-		Durl []struct {
-			Url string `json: "durl"`
-		} `json:"durl"`
-	} `json: "data"`
-}
-
-func main() {
-	app := &cli.App{
-		Name:  "bvd",
-		Usage: "快速、高效、易用的下载B站视频 CLI 工具",
-		Commands: []*cli.Command{
-			{
-				Name:      "download",
-				Usage:     "下载指定 BV 号的视频",
-				Action:    downloadAction,
-				ArgsUsage: "<BVID> 欲下载视频的 BV 号",
-			},
-		},
-
-		Action: func(c *cli.Context) error {
-			args := c.Args()
-			if args.Len() == 0 {
-				cli.ShowAppHelp(c)
-			}
-			return nil
-		},
-	}
-
-	err := app.Run(os.Args)
-	if err != nil {
-		log.Fatal(err)
-	}
-}
-
-func downloadAction(c *cli.Context) error {
-	// 从命令行获取 BVID 参数
-	bvid := c.Args().First()
-
-	if bvid == "" {
-		return fmt.Errorf("请提供 BV 号")
-	}
-
-	return startDownload(bvid)
-}
-
-func startDownload(bvid string) error {
-	video, err := getVideoBaseInfo(bvid)
-	if err != nil {
-		return fmt.Errorf("获取视频信息失败：%w", err)
-	}
-
-	err = downloadVideo(video, bvid)
-	if err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func getVideoBaseInfo(bvid string) (VideoBaseInfo, error) {
-	var APIUrl string = "https://api.bilibili.com/x/player/pagelist?bvid="
-	APIUrl += bvid
-	client := &http.Client{
-		Timeout: 30 * time.Second,
-	}
-
-	// 发送 GET 请求
-	resp, err := client.Get(APIUrl)
-	if err != nil {
-		return VideoBaseInfo{}, fmt.Errorf("发送请求失败: %w", err)
-	}
-	defer resp.Body.Close()
-
-	body, err := io.ReadAll(resp.Body)
-	if err != nil {
-		return VideoBaseInfo{}, fmt.Errorf("读取响应失败: %w", err)
-	}
-
-	var result VideoBaseInfo
-	if err := json.Unmarshal(body, &result); err != nil {
-		return VideoBaseInfo{}, fmt.Errorf("JSON 解析失败： %w", err)
-	}
-
-	return result, nil
-}
-
-func getDownloadUrl(video VideoBaseInfo, bvid string) ([]string, error) {
-	cid := make([]int, len(video.Data))
-	for i := 0; i < len(video.Data); i++ {
-		cid[i] = video.Data[i].Cid
-	}
-
-	var downloadUrls = make([]string, len(video.Data))
-	var result getDownloadUrlJson
-	client := &http.Client{Timeout: 30 * time.Second}
-
-	for j := 0; j < len(cid); j++ {
-		apiUrl := fmt.Sprintf("https://api.bilibili.com/x/player/playurl?&cid=%d&bvid=%s&qn=80", cid[j], bvid)
-
-		resp, err := client.Get(apiUrl)
-		if err != nil {
-			return nil, fmt.Errorf("CID %d 请求失败: %w", cid[j], err)
-		}
-
-		body, err := io.ReadAll(resp.Body)
-		if err != nil {
-			resp.Body.Close()
-			return nil, fmt.Errorf("CID %d 读取响应失败: %w", cid[j], err)
-		}
-
-		if err := json.Unmarshal(body, &result); err != nil {
-			return nil, fmt.Errorf("CID %d JSON解析失败: %w", cid[j], err)
-		}
-
-		downloadUrls[j] = result.Data.Durl[0].Url
-	}
-
-	return downloadUrls, nil
-}
-
-func downloadVideo(video VideoBaseInfo, bvid string) error {
-	var urls []string
-	urls, err := getDownloadUrl(video, bvid)
-	if err != nil {
-		return fmt.Errorf("获取视频下载链接失败：%w", err)
-	}
-
-	// 创建下载目录
-	downloadDir := "./downloads/"
-	if err := os.MkdirAll(downloadDir, 0755); err != nil {
-		return fmt.Errorf("创建下载目录失败：%w", err)
-	}
-
-	fmt.Printf("成功获取 %d 个下载链接\n", len(urls))
-
-	for i := 0; i < len(urls); i++ {
-		fmt.Printf("开始下载第 %d 个文件\n", i+1)
-
-		// 创建支持重定向的 HTTP 客户端
-		client := &http.Client{
-			CheckRedirect: func(req *http.Request, via []*http.Request) error {
-				return nil
-			},
-		}
-
-		req, err := http.NewRequest("GET", urls[i], nil)
-		if err != nil {
-			return err
-		}
-
-		req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36")
-		req.Header.Set("referer", "https://www.bilibili.com")
-
-		// 发送请求
-		resp, err := client.Do(req)
-		if err != nil {
-			return fmt.Errorf("HTTP请求失败：%w", err)
-		}
-		defer resp.Body.Close()
-
-		// 检查响应状态
-		if resp.StatusCode != http.StatusOK {
-			return fmt.Errorf("服务器返回错误状态码: %d", resp.StatusCode)
-		}
-
-		// 构建文件名
-		filename := filepath.Join(downloadDir, video.Data[i].Part+".mp4")
-		fmt.Printf("保存到: %s\n", filename)
-
-		// 创建文件
-		out, err := os.Create(filename)
-		if err != nil {
-			return fmt.Errorf("创建文件失败：%w", err)
-		}
-
-		// 下载文件
-		_, err = io.Copy(out, resp.Body)
-		if err != nil {
-			out.Close()
-			return fmt.Errorf("下载失败：%w", err)
-		}
-
-		// 关闭文件
-		if err := out.Close(); err != nil {
-			return fmt.Errorf("关闭文件失败：%w", err)
-		}
-
-		fmt.Printf("文件下载成功: %s\n", filename)
-
-	}
-
-	return nil
-}