From b336d942774c55521cb5828a3f4af4b3bd9ba66f Mon Sep 17 00:00:00 2001
From: Buravit Yenjit <buravit.yj@gmail.com>
Date: Tue, 1 Apr 2025 13:40:22 +0700
Subject: [PATCH] feat: add knowledgeHub repository

---
 .../repository/postgres_knowledgeHub.go       | 184 ++++++++++++++++++
 1 file changed, 184 insertions(+)
 create mode 100644 backend/internal/repository/postgres_knowledgeHub.go

diff --git a/backend/internal/repository/postgres_knowledgeHub.go b/backend/internal/repository/postgres_knowledgeHub.go
new file mode 100644
index 0000000..8e4acb9
--- /dev/null
+++ b/backend/internal/repository/postgres_knowledgeHub.go
@@ -0,0 +1,184 @@
+package repository
+
+import (
+	"context"
+	"strings"
+
+	"github.com/forfarm/backend/internal/domain"
+	"github.com/google/uuid"
+)
+
+type postgresKnowledgeHubRepository struct {
+	conn Connection
+}
+
+func NewPostgresKnowledgeHub(conn Connection) domain.KnowledgeHubRepository {
+	return &postgresKnowledgeHubRepository{conn: conn}
+}
+
+func (p *postgresKnowledgeHubRepository) fetchArticles(ctx context.Context, query string, args ...interface{}) ([]domain.KnowledgeArticle, error) {
+	rows, err := p.conn.Query(ctx, query, args...)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var articles []domain.KnowledgeArticle
+	for rows.Next() {
+		var a domain.KnowledgeArticle
+		if err := rows.Scan(
+			&a.UUID,
+			&a.Title,
+			&a.Content,
+			&a.Author,
+			&a.PublishDate,
+			&a.ReadTime,
+			&a.Categories,
+			&a.CreatedAt,
+			&a.UpdatedAt,
+		); err != nil {
+			return nil, err
+		}
+		articles = append(articles, a)
+	}
+	return articles, nil
+}
+
+func (p *postgresKnowledgeHubRepository) GetArticleByID(ctx context.Context, uuid string) (domain.KnowledgeArticle, error) {
+	query := `
+		SELECT uuid, title, content, author, publish_date, read_time, categories, created_at, updated_at
+		FROM knowledge_articles
+		WHERE uuid = $1`
+
+	articles, err := p.fetchArticles(ctx, query, uuid)
+	if err != nil {
+		return domain.KnowledgeArticle{}, err
+	}
+	if len(articles) == 0 {
+		return domain.KnowledgeArticle{}, domain.ErrNotFound
+	}
+	return articles[0], nil
+}
+
+func (p *postgresKnowledgeHubRepository) GetArticlesByCategory(ctx context.Context, category string) ([]domain.KnowledgeArticle, error) {
+	query := `
+		SELECT uuid, title, content, author, publish_date, read_time, categories, created_at, updated_at
+		FROM knowledge_articles
+		WHERE $1 = ANY(categories)`
+
+	return p.fetchArticles(ctx, query, category)
+}
+
+func (p *postgresKnowledgeHubRepository) GetAllArticles(ctx context.Context) ([]domain.KnowledgeArticle, error) {
+	query := `
+		SELECT uuid, title, content, author, publish_date, read_time, categories, created_at, updated_at
+		FROM knowledge_articles`
+
+	return p.fetchArticles(ctx, query)
+}
+
+func (p *postgresKnowledgeHubRepository) CreateOrUpdateArticle(ctx context.Context, article *domain.KnowledgeArticle) error {
+	if strings.TrimSpace(article.UUID) == "" {
+		article.UUID = uuid.New().String()
+	}
+
+	query := `  
+        INSERT INTO knowledge_articles (uuid, title, content, author, publish_date, read_time, categories, created_at, updated_at)  
+        VALUES ($1, $2, $3, $4, $5, $6, $7, NOW(), NOW())
+        ON CONFLICT (uuid) DO UPDATE
+        SET title = EXCLUDED.title,
+            content = EXCLUDED.content,
+            author = EXCLUDED.author,
+            publish_date = EXCLUDED.publish_date,
+            read_time = EXCLUDED.read_time,
+            categories = EXCLUDED.categories,
+            updated_at = NOW()
+        RETURNING uuid, created_at, updated_at`
+
+	return p.conn.QueryRow(
+		ctx,
+		query,
+		article.UUID,
+		article.Title,
+		article.Content,
+		article.Author,
+		article.PublishDate,
+		article.ReadTime,
+		article.Categories,
+	).Scan(&article.UUID, &article.CreatedAt, &article.UpdatedAt)
+}
+
+func (p *postgresKnowledgeHubRepository) DeleteArticle(ctx context.Context, uuid string) error {
+	query := `DELETE FROM knowledge_articles WHERE uuid = $1`
+	_, err := p.conn.Exec(ctx, query, uuid)
+	return err
+}
+
+func (p *postgresKnowledgeHubRepository) fetchTableOfContents(ctx context.Context, query string, args ...interface{}) ([]domain.TableOfContent, error) {
+	rows, err := p.conn.Query(ctx, query, args...)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var tocItems []domain.TableOfContent
+	for rows.Next() {
+		var t domain.TableOfContent
+		if err := rows.Scan(
+			&t.UUID,
+			&t.ArticleID,
+			&t.Title,
+			&t.Order,
+			&t.CreatedAt,
+			&t.UpdatedAt,
+		); err != nil {
+			return nil, err
+		}
+		tocItems = append(tocItems, t)
+	}
+	return tocItems, nil
+}
+
+func (p *postgresKnowledgeHubRepository) GetTableOfContents(ctx context.Context, articleID string) ([]domain.TableOfContent, error) {
+	query := `
+		SELECT uuid, article_id, title, "order", created_at, updated_at
+		FROM table_of_contents
+		WHERE article_id = $1
+		ORDER BY "order" ASC`
+
+	return p.fetchTableOfContents(ctx, query, articleID)
+}
+
+func (p *postgresKnowledgeHubRepository) fetchRelatedArticles(ctx context.Context, query string, args ...interface{}) ([]domain.RelatedArticle, error) {
+	rows, err := p.conn.Query(ctx, query, args...)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var relatedArticles []domain.RelatedArticle
+	for rows.Next() {
+		var r domain.RelatedArticle
+		if err := rows.Scan(
+			&r.UUID,
+			&r.ArticleID,
+			&r.RelatedTitle,
+			&r.RelatedTag,
+			&r.CreatedAt,
+			&r.UpdatedAt,
+		); err != nil {
+			return nil, err
+		}
+		relatedArticles = append(relatedArticles, r)
+	}
+	return relatedArticles, nil
+}
+
+func (p *postgresKnowledgeHubRepository) GetRelatedArticles(ctx context.Context, articleID string) ([]domain.RelatedArticle, error) {
+	query := `
+		SELECT uuid, article_id, related_title, related_tag, created_at, updated_at
+		FROM related_articles
+		WHERE article_id = $1`
+
+	return p.fetchRelatedArticles(ctx, query, articleID)
+}