Enforce discord embed size limits

Signed-off-by: Joshua Castle <26531652+Kas-tle@users.noreply.github.com>

Author: Kas-tle

package.json

@@ -1,6 +1,6 @@
 {
     "name": "base-release-action",
-    "version": "1.5.2",
+    "version": "1.5.3",
     "description": "An action to create incremented releases in a similar style to Jenkins",
     "repository": "https://github.com/Kas-tle/base-release-action.git",
     "author": "Joshua Castle <packages@kastle.dev>",

src/action/hook.ts

@@ -24,37 +24,91 @@ export async function sendWebhook(inp: {inputs: Inputs, api: OctokitApi, repoDat
 
     const thumbnail= `https://opengraph.githubassets.com/1/${owner}/${repo}/releases/tag/${tag}`;
 
-    let assets = '';
+    // Prepare Asset Fields (Split if > 1024)
+    let assetLines: string[] = [];
     for (const asset of updatedRelease.data.assets) {
-        assets += `- :page_facing_up: [${asset.name}](${asset.browser_download_url})\n`;
+        assetLines.push(`- :page_facing_up: [${asset.name}](${asset.browser_download_url})`);
     }
-    assets += `- :package: [Source code (zip)](${updatedRelease.data.zipball_url})\n`;
-    assets += `- :package: [Source code (tar.gz)](${updatedRelease.data.tarball_url})\n`;
+    assetLines.push(`- :package: [Source code (zip)](${updatedRelease.data.zipball_url})`);
+    assetLines.push(`- :package: [Source code (tar.gz)](${updatedRelease.data.tarball_url})`);
 
+    const assetFields: { name: string; value: string; inline: boolean }[] = [];
+    let currentAssetChunk = '';
+    
+    for (const line of assetLines) {
+        if (currentAssetChunk.length + line.length + 1 > 1024) {
+            assetFields.push({ name: 'Assets', value: currentAssetChunk, inline: false });
+            currentAssetChunk = '';
+        }
+        currentAssetChunk += line + '\n';
+    }
+    if (currentAssetChunk) {
+        assetFields.push({ name: 'Assets', value: currentAssetChunk, inline: false });
+    }
+
+    // Prepare Static Fields
     const time = Math.floor(new Date(updatedRelease.data.created_at).getTime() / 1000);
-    const author = updatedRelease.data.author.type === 'User' ? updatedRelease.data.author.login : updatedRelease.data.author.login.replace('[bot]', '');
     const sha = inputs.changes[inputs.changes.length - 1].commit.slice(0, 7);
     const statusEmoji = failed ? ':red_circle:' : ':green_circle:';
     const status = failed ? 'Failed' : 'Success';
     const runID = process.env.GITHUB_RUN_ID!;
 
+    const staticFields = [
+        { name: '', value: `:watch: <t:${time}:R>`, inline: true },
+        { name: '', value: `:label: [${tag}](${url}/${owner}/${repo}/tree/${tag})`, inline: true },
+        { name: '', value: `:lock_with_ink_pen: [${sha}](${url}/${owner}/${repo}/commit/${sha})`, inline: true },
+        { name: '', value: `${statusEmoji} [${status}](${url}/${owner}/${repo}/actions/runs/${runID})`, inline: true }
+    ];
+
+    // Enforce Field Count Limit (Max 25)
+    // We have 4 static fields, leaving 21 slots for assets
+    if (assetFields.length > 21) {
+        assetFields.length = 21;
+    }
+    const allFields = [...assetFields, ...staticFields];
+
+    // Truncate & Calculate Sizes
+    // Author Name: Max 256
+    const embedAuthorName = `${owner}/${repo}`.substring(0, 256);
+    
+    // Title: Max 256
+    const embedTitle = inputs.release.name.substring(0, 256);
+
+    // Footer: Max 2048
+    let author = updatedRelease.data.author.type === 'User' ? updatedRelease.data.author.login : updatedRelease.data.author.login.replace('[bot]', '');
+    const embedFooterText = `Released by ${author}`.substring(0, 2048);
+
+    // Calculate current used size (excluding description)
+    let currentTotalSize = 0;
+    currentTotalSize += embedAuthorName.length;
+    currentTotalSize += embedTitle.length;
+    currentTotalSize += embedFooterText.length;
+    
+    for (const f of allFields) {
+        currentTotalSize += (f.name.length || 0) + (f.value.length || 0);
+    }
+
+    // Description: Max 4096, but Total Embed must be <= 6000
+    const availableForDesc = 6000 - currentTotalSize;
+    const maxDesc = Math.min(4096, availableForDesc);
+    const description = (inputs.release.body || '').substring(0, Math.max(0, maxDesc));
+
     const embed = new Embed()
         .setTimestamp()
         .setAuthor({
-            name: `${owner}/${repo}`,
+            name: embedAuthorName,
             url: `${url}/${owner}/${repo}`,
             icon_url: `${url}/${owner}.png`
         })
         .setColor(color)
-        .setTitle(inputs.release.name)
+        .setTitle(embedTitle)
         .setUrl(updatedRelease.data.html_url)
-        .setDescription(inputs.release.body.substring(0, 4000))
-        .addField({ name: 'Assets', value: assets, inline: false })
-        .addField({ name: '', value: `:watch: <t:${time}:R>`, inline: true })
-        .addField({ name: '', value: `:label: [${tag}](${url}/${owner}/${repo}/tree/${tag})`, inline: true })
-        .addField({ name: '', value: `:lock_with_ink_pen: [${sha}](${url}/${owner}/${repo}/commit/${sha})`, inline: true })
-        .addField({ name: '', value: `${statusEmoji} [${status}](${url}/${owner}/${repo}/actions/runs/${runID})`, inline: true })
-        .setFooter({ text: `Released by ${author}`, icon_url: updatedRelease.data.author.avatar_url })
+        .setDescription(description)
+        .setFooter({ text: embedFooterText, icon_url: updatedRelease.data.author.avatar_url })
+
+    for (const field of allFields) {
+        embed.addField(field);
+    }
 
     if (thumbnail) {
         embed.setImage({ url: thumbnail });