Feature/video download

apps/web/src/app/api/download-videos/route.ts

@@ -0,0 +1,355 @@
+// apps/web/src/app/api/download-videos/route.ts
+
+import { NextRequest, NextResponse } from "next/server";
+import { z } from "zod";
+import { spawn } from "child_process";
+
+/**
+ * Validates the request body for video URL.
+ */
+const infoRequestSchema = z.object({
+  url: z.string().url("Invalid URL provided"),
+});
+
+/**
+ * Validates the request body for search keyword.
+ */
+const searchRequestSchema = z.object({
+  keyword: z.string().min(1, "Keyword is required"),
+  page: z.number().int().positive().optional().default(1),
+  pageSize: z.number().int().min(1).max(50).optional().default(20),
+});
+
+/**
+ * Handles POST requests to /api/download-videos with action parameter.
+ * Supports: search, info, download
+ */
+export async function POST(request: NextRequest) {
+  try {
+    const { searchParams } = new URL(request.url);
+    const action = searchParams.get("action");
+
+    switch (action) {
+      case "search":
+        return await handleSearch(request);
+      case "info":
+        return await handleVideoInfo(request);
+      case "download":
+        return await handleDownload(request);
+      default:
+        return NextResponse.json(
+          { error: "Invalid action. Use 'search', 'info', or 'download'." },
+          { status: 400 }
+        );
+    }
+  } catch (error) {
+    console.error("Video API error:", error);
+    return NextResponse.json(
+      {
+        error: "Internal server error",
+        message: "An unexpected error occurred",
+      },
+      { status: 500 }
+    );
+  }
+}
+
+/**
+ * Handles video search using yt-dlp.
+ * Searches videos based on keyword and pagination.
+ */
+async function handleSearch(request: NextRequest) {
+  try {
+    const rawBody = await request.json().catch(() => null);
+    if (!rawBody) {
+      return NextResponse.json(
+        { error: "Invalid JSON in request body" },
+        { status: 400 }
+      );
+    }
+
+    const validationResult = searchRequestSchema.safeParse(rawBody);
+    if (!validationResult.success) {
+      return NextResponse.json(
+        {
+          error: "Invalid request parameters",
+          details: validationResult.error.flatten().fieldErrors,
+        },
+        { status: 400 }
+      );
+    }
+
+    const { keyword, page, pageSize } = validationResult.data;
+    const startIndex = (page - 1) * pageSize + 1;
+    const endIndex = page * pageSize;
+
+    return new Promise((resolve) => {
+      const ytDlp = spawn("yt-dlp", [
+        "--dump-single-json",
+        "--flat-playlist",
+        "--no-warnings",
+        "--playlist-start",
+        startIndex.toString(),
+        "--playlist-end",
+        endIndex.toString(),
+        `ytsearch${pageSize}:${keyword}`,
+      ]);
+
+      let stdoutData = "";
+      let stderrData = "";
+
+      ytDlp.stdout.on("data", (data) => {
+        stdoutData += data.toString();
+      });
+
+      ytDlp.stderr.on("data", (data) => {
+        stderrData += data.toString();
+      });
+
+      ytDlp.on("close", (code) => {
+        try {
+          if (code !== 0) {
+            return resolve(
+              NextResponse.json(
+                {
+                  success: false,
+                  error: `yt-dlp process exited with code ${code}`,
+                  details: stderrData,
+                },
+                { status: 500 }
+              )
+            );
+          }
+
+          if (!stdoutData.trim()) {
+            return resolve(
+              NextResponse.json(
+                {
+                  success: false,
+                  error: "No output from yt-dlp",
+                  details: stderrData || "Process completed with no output",
+                },
+                { status: 500 }
+              )
+            );
+          }
+
+          const result = JSON.parse(stdoutData);
+          resolve(
+            NextResponse.json({
+              success: true,
+              data: Array.isArray(result) ? result : [result],
+            })
+          );
+        } catch (parseError) {
+          resolve(
+            NextResponse.json(
+              {
+                success: false,
+                error: "Error parsing yt-dlp output",
+                details: parseError instanceof Error ? parseError.message : "Unknown error",
+                rawOutput: stdoutData,
+              },
+              { status: 500 }
+            )
+          );
+        }
+      });
+
+      ytDlp.on("error", (error) => {
+        resolve(
+          NextResponse.json(
+            {
+              success: false,
+              error: "Failed to start yt-dlp process",
+              details: error.message,
+            },
+            { status: 500 }
+          )
+        );
+      });
+    });
+  } catch (error) {
+    return NextResponse.json(
+      {
+        success: false,
+        error: error instanceof Error ? error.message : "Unknown error occurred",
+      },
+      { status: 500 }
+    );
+  }
+}
+
+/**
+ * Fetches video metadata using yt-dlp.
+ * Returns title, duration, formats, thumbnails, etc.
+ */
+async function handleVideoInfo(request: NextRequest) {
+  try {
+    const rawBody = await request.json().catch(() => null);
+    if (!rawBody) {
+      return NextResponse.json(
+        { error: "Invalid JSON in request body" },
+        { status: 400 }
+      );
+    }
+
+    const validationResult = infoRequestSchema.safeParse(rawBody);
+    if (!validationResult.success) {
+      return NextResponse.json(
+        {
+          error: "Invalid request parameters",
+          details: validationResult.error.flatten().fieldErrors,
+        },
+        { status: 400 }
+      );
+    }
+
+    const { url } = validationResult.data;
+
+    return new Promise((resolve) => {
+      const ytDlp = spawn("yt-dlp", [
+        "--dump-single-json",
+        "--no-warnings",
+        "--compat-options",
+        "no-youtube-channel-redirect",
+        url,
+      ]);
+
+      let stdoutData = "";
+      let stderrData = "";
+
+      ytDlp.stdout.on("data", (data) => {
+        stdoutData += data.toString();
+      });
+
+      ytDlp.stderr.on("data", (data) => {
+        stderrData += data.toString();
+      });
+
+      ytDlp.on("close", (code) => {
+        try {
+          if (code !== 0) {
+            return resolve(
+              NextResponse.json(
+                {
+                  success: false,
+                  error: `yt-dlp process exited with code ${code}`,
+                  details: stderrData,
+                },
+                { status: 500 }
+              )
+            );
+          }
+
+          if (!stdoutData.trim()) {
+            return resolve(
+              NextResponse.json(
+                {
+                  success: false,
+                  error: "No output from yt-dlp",
+                  details: stderrData || "Process completed with no output",
+                },
+                { status: 500 }
+              )
+            );
+          }
+
+          const result = JSON.parse(stdoutData);
+          resolve(
+            NextResponse.json({
+              success: true,
+              data: result,
+            })
+          );
+        } catch (parseError) {
+          resolve(
+            NextResponse.json(
+              {
+                success: false,
+                error: "Error parsing yt-dlp output",
+                details: parseError instanceof Error ? parseError.message : "Unknown error",
+                rawOutput: stdoutData,
+              },
+              { status: 500 }
+            )
+          );
+        }
+      });
+
+      ytDlp.on("error", (error) => {
+        resolve(
+          NextResponse.json(
+            {
+              success: false,
+              error: "Failed to start yt-dlp process",
+              details: error.message,
+            },
+            { status: 500 }
+          )
+        );
+      });
+    });
+  } catch (error) {
+    return NextResponse.json(
+      {
+        success: false,
+        error: error instanceof Error ? error.message : "Unknown error occurred",
+      },
+      { status: 500 }
+    );
+  }
+}
+
+/**
+ * Initiates video download process (placeholder).
+ * In the future, this will spawn yt-dlp to download the video.
+ *
+ * @param request - Incoming NextRequest
+ * @returns NextResponse with download status
+ */
+async function handleDownload(request: NextRequest) {
+  try {
+    const rawBody = await request.json().catch(() => null);
+    if (!rawBody) {
+      return NextResponse.json(
+        { error: "Invalid JSON in request body" },
+        { status: 400 }
+      );
+    }
+
+    const validationResult = infoRequestSchema.safeParse(rawBody);
+    if (!validationResult.success) {
+      return NextResponse.json(
+        {
+          error: "Invalid request parameters",
+          details: validationResult.error.flatten().fieldErrors,
+        },
+        { status: 400 }
+      );
+    }
+
+    const { url } = validationResult.data;
+
+    // TODO: 实际调用 yt-dlp 下载视频文件
+    // 当前返回模拟响应
+    return NextResponse.json({
+      success: true,
+      message: "Download started (placeholder)",
+      data: {
+        url,
+        status: "queued",
+        downloadId: crypto.randomUUID(),
+        startedAt: new Date().toISOString(),
+      },
+    });
+  } catch (error) {
+    return NextResponse.json(
+      {
+        success: false,
+        error: error instanceof Error ? error.message : "Unknown error occurred",
+      },
+      { status: 500 }
+    );
+  }
+}