From e0deaec695650d22c92512cc2672ba3aade96eed Mon Sep 17 00:00:00 2001
From: syuilo <syuilotan@yahoo.co.jp>
Date: Fri, 7 Sep 2018 19:23:39 +0900
Subject: [PATCH] Implement new endpoint

---
 .../api/endpoints/aggregation/hashtags.ts     | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 src/server/api/endpoints/aggregation/hashtags.ts

diff --git a/src/server/api/endpoints/aggregation/hashtags.ts b/src/server/api/endpoints/aggregation/hashtags.ts
new file mode 100644
index 0000000000..0daf42427b
--- /dev/null
+++ b/src/server/api/endpoints/aggregation/hashtags.ts
@@ -0,0 +1,64 @@
+import Note from '../../../../models/note';
+import Meta from '../../../../models/meta';
+
+export default () => new Promise(async (res, rej) => {
+	const meta = await Meta.findOne({});
+	const hidedTags = (meta.hidedTags || []).map(t => t.toLowerCase());
+
+	const span = 1000 * 60 * 60 * 24 * 7; // 1週間
+
+	//#region 1. 指定期間の内に投稿されたハッシュタグ(とユーザーのペア)を集計
+	const data = await Note.aggregate([{
+		$match: {
+			createdAt: {
+				$gt: new Date(Date.now() - span)
+			},
+			tagsLower: {
+				$exists: true,
+				$ne: []
+			}
+		}
+	}, {
+		$unwind: '$tagsLower'
+	}, {
+		$group: {
+			_id: { tag: '$tagsLower', userId: '$userId' }
+		}
+	}]) as Array<{
+		_id: {
+			tag: string;
+			userId: any;
+		}
+	}>;
+	//#endregion
+
+	if (data.length == 0) {
+		return res([]);
+	}
+
+	let tags: Array<{
+		name: string;
+		count: number;
+	}> = [];
+
+	// カウント
+	data.map(x => x._id).forEach(x => {
+		// ブラックリストに登録されているタグなら弾く
+		if (hidedTags.includes(x.tag)) return;
+
+		const i = tags.findIndex(tag => tag.name == x.tag);
+		if (i != -1) {
+			tags[i].count++;
+		} else {
+			tags.push({
+				name: x.tag,
+				count: 1
+			});
+		}
+	});
+
+	// タグを人気順に並べ替え
+	tags = tags.sort((a, b) => b.count - a.count);
+
+	res(tags);
+});