From 0713b4be87d15382804abfac20cf058846369657 Mon Sep 17 00:00:00 2001
From: oppiliappan <me@oppi.li>
Date: Tue, 30 Sep 2025 23:59:38 +0100
Subject: [PATCH] appview/languages: fix logic bug in updating language
 breakdowns
Change-Id: zomkuzmzokvlnmwvrmrqwqkkqqsxoxwk

Signed-off-by: oppiliappan <me@oppi.li>
---
 appview/db/language.go      | 35 +++++++++++++++++++++++++++++++++++
 appview/repo/index.go       | 13 ++++++++++++-
 appview/state/knotstream.go | 16 ++++++++++++++++
 3 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/appview/db/language.go b/appview/db/language.go
index ea3a2b33..7e2b9e27 100644
--- a/appview/db/language.go
+++ b/appview/db/language.go
@@ -1,9 +1,12 @@
 package db
 
 import (
+	"database/sql"
 	"fmt"
 	"strings"
 
+	"github.com/bluesky-social/indigo/atproto/syntax"
+	"tangled.org/core/appview/db"
 	"tangled.org/core/appview/models"
 )
 
@@ -82,3 +85,35 @@ func InsertRepoLanguages(e Execer, langs []models.RepoLanguage) error {
 
 	return nil
 }
+
+func DeleteRepoLanguages(e Execer, filters ...filter) error {
+	var conditions []string
+	var args []any
+	for _, filter := range filters {
+		conditions = append(conditions, filter.Condition())
+		args = append(args, filter.Arg()...)
+	}
+
+	whereClause := ""
+	if conditions != nil {
+		whereClause = " where " + strings.Join(conditions, " and ")
+	}
+
+	query := fmt.Sprintf(`delete from repo_languages %s`, whereClause)
+
+	_, err := e.Exec(query, args...)
+	return err
+}
+
+func UpdateRepoLanguages(tx *sql.Tx, repoAt syntax.ATURI, ref string, langs []models.RepoLanguage) error {
+	err := DeleteRepoLanguages(
+		tx,
+		FilterEq("repo_at", repoAt),
+		FilterEq("ref", ref),
+	)
+	if err != nil {
+		return fmt.Errorf("failed to delete existing languages: %w", err)
+	}
+
+	return InsertRepoLanguages(tx, langs)
+}
diff --git a/appview/repo/index.go b/appview/repo/index.go
index db4bfcd7..179f3646 100644
--- a/appview/repo/index.go
+++ b/appview/repo/index.go
@@ -200,12 +200,23 @@ func (rp *Repo) getLanguageInfo(
 			})
 		}
 
+		tx, err := rp.db.Begin()
+		if err != nil {
+			return nil, err
+		}
+		defer tx.Rollback()
+
 		// update appview's cache
-		err = db.InsertRepoLanguages(rp.db, langs)
+		err = db.UpdateRepoLanguages(tx, f.RepoAt(), currentRef, langs)
 		if err != nil {
 			// non-fatal
 			log.Println("failed to cache lang results", err)
 		}
+
+		err = tx.Commit()
+		if err != nil {
+			return nil, err
+		}
 	}
 
 	var total int64
diff --git a/appview/state/knotstream.go b/appview/state/knotstream.go
index 8a64fbe6..3ce16006 100644
--- a/appview/state/knotstream.go
+++ b/appview/state/knotstream.go
@@ -172,6 +172,22 @@ func updateRepoLanguages(d *db.DB, record tangled.GitRefUpdate) error {
 		})
 	}
 
+	tx, err := d.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	// update appview's cache
+	err = db.UpdateRepoLanguages(tx, repo.RepoAt(), ref.Short(), langs)
+	if err != nil {
+		// non-fatal
+	}
+
+	err = tx.Commit()
+	if err != nil {
+		return err
+	}
 	return db.InsertRepoLanguages(d, langs)
 }
 
-- 
2.43.0