From d2ffde8469f54254278fde4ce73243f3b174a846 Mon Sep 17 00:00:00 2001
From: LittleSheep <littlesheep.code@hotmail.com>
Date: Mon, 9 Dec 2024 22:14:30 +0800
Subject: [PATCH] :sparkles: Featured posts

---
 pkg/internal/http/api/index.go              |  2 +-
 pkg/internal/http/api/recommendation_api.go | 55 +++++++++------------
 pkg/internal/services/featured.go           | 40 +++++++++++++++
 3 files changed, 63 insertions(+), 34 deletions(-)
 create mode 100644 pkg/internal/services/featured.go

diff --git a/pkg/internal/http/api/index.go b/pkg/internal/http/api/index.go
index 10d40ad..3613b20 100644
--- a/pkg/internal/http/api/index.go
+++ b/pkg/internal/http/api/index.go
@@ -20,7 +20,7 @@ func MapAPIs(app *fiber.App, baseURL string) {
 
 		recommendations := api.Group("/recommendations").Name("Recommendations API")
 		{
-			recommendations.Get("/", listRecommendationNews)
+			recommendations.Get("/", listRecommendation)
 			recommendations.Get("/friends", listRecommendationFriends)
 			recommendations.Get("/shuffle", listRecommendationShuffle)
 		}
diff --git a/pkg/internal/http/api/recommendation_api.go b/pkg/internal/http/api/recommendation_api.go
index 908a6c6..741f5f6 100644
--- a/pkg/internal/http/api/recommendation_api.go
+++ b/pkg/internal/http/api/recommendation_api.go
@@ -3,6 +3,7 @@ package api
 import (
 	"git.solsynth.dev/hypernet/interactive/pkg/internal/database"
 	"git.solsynth.dev/hypernet/interactive/pkg/internal/gap"
+	"git.solsynth.dev/hypernet/interactive/pkg/internal/models"
 	"git.solsynth.dev/hypernet/interactive/pkg/internal/services"
 	"git.solsynth.dev/hypernet/nexus/pkg/nex/sec"
 	"git.solsynth.dev/hypernet/nexus/pkg/proto"
@@ -12,45 +13,33 @@ import (
 	"github.com/samber/lo"
 )
 
-func listRecommendationNews(c *fiber.Ctx) error {
-	take := c.QueryInt("take", 0)
-	offset := c.QueryInt("offset", 0)
+func listRecommendation(c *fiber.Ctx) error {
+	const featuredMax = 3
 
-	tx := database.C
-
-	var err error
-	if tx, err = universalPostFilter(c, tx); err != nil {
-		return err
-	}
-
-	countTx := tx
-	count, err := services.CountPost(countTx)
+	posts, err := services.GetFeaturedPosts(featuredMax)
 	if err != nil {
 		return fiber.NewError(fiber.StatusInternalServerError, err.Error())
 	}
 
-	order := "published_at DESC"
-	if c.QueryBool("featured", false) {
-		order = "published_at DESC, (COALESCE(total_upvote, 0) - COALESCE(total_downvote, 0)) DESC"
-	}
-
-	items, err := services.ListPost(tx, take, offset, order)
-	if err != nil {
-		return fiber.NewError(fiber.StatusBadRequest, err.Error())
-	}
-
-	if c.QueryBool("truncate", true) {
-		for _, item := range items {
-			if item != nil {
-				item = lo.ToPtr(services.TruncatePostContent(*item))
-			}
-		}
-	}
-
-	return c.JSON(fiber.Map{
-		"count": count,
-		"data":  items,
+	postIdx := lo.Map(posts, func(item models.Post, index int) uint {
+		return item.ID
 	})
+
+	tx := database.C.Where("id IN ?", postIdx)
+	newPosts, err := services.ListPost(tx, featuredMax, 0, " DESC")
+	if err != nil {
+		return fiber.NewError(fiber.StatusInternalServerError, err.Error())
+	}
+	newPostMap := lo.SliceToMap(newPosts, func(item *models.Post) (uint, models.Post) {
+		return item.ID, *item
+	})
+
+	// Revert the position
+	for idx, item := range posts {
+		posts[idx] = newPostMap[item.ID]
+	}
+
+	return c.JSON(posts)
 }
 
 func listRecommendationFriends(c *fiber.Ctx) error {
diff --git a/pkg/internal/services/featured.go b/pkg/internal/services/featured.go
new file mode 100644
index 0000000..4a221ab
--- /dev/null
+++ b/pkg/internal/services/featured.go
@@ -0,0 +1,40 @@
+package services
+
+import (
+	"git.solsynth.dev/hypernet/interactive/pkg/internal/database"
+	"git.solsynth.dev/hypernet/interactive/pkg/internal/models"
+	"time"
+)
+
+// GetFeaturedPosts How to determine featured posts?
+// Get the most upvoted posts in the last 7 days
+// And then how to get the upvote count of each post in the last 7 days?
+// We will get the reactions that attitude equals to 1 and created within the last 7 days
+// By the way, the upvote count will subtract the downvote count
+// Notice, this function is a raw query, it is not recommended to return the result directly
+// Instead, you should get the id and query it again via the ListPost function
+func GetFeaturedPosts(count int) ([]models.Post, error) {
+	deadline := time.Now().Add(-7 * 24 * time.Hour)
+
+	var posts []models.Post
+	if err := database.C.Raw(`
+		SELECT p.*
+        FROM posts p
+        JOIN (
+            SELECT
+                post_id,
+                SUM(CASE WHEN attitude = 1 THEN 1 ELSE 0 END) -
+                SUM(CASE WHEN attitude = 2 THEN 1 ELSE 0 END) AS social_points
+            FROM reactions
+            WHERE created_at >= ?
+            GROUP BY post_id
+            ORDER BY social_points DESC
+            LIMIT ?
+        ) t ON p.id = t.post_id
+        ORDER BY t.social_points DESC, p.published_at DESC
+    `, deadline, count).Scan(&posts).Error; err != nil {
+		return posts, err
+	}
+
+	return posts, nil
+}