From 595bdb241aec2c568b2103dcbdfa79dcd2b9eebf Mon Sep 17 00:00:00 2001
From: Kailash Nadh <kailash@nadh.in>
Date: Fri, 2 Nov 2018 00:07:02 +0530
Subject: [PATCH] Set all campaign templates to default when a used template is
 deleted

---
 queries.sql  | 13 +++++++++++--
 templates.go | 10 ++++++++--
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/queries.sql b/queries.sql
index acf8996..e93da46 100644
--- a/queries.sql
+++ b/queries.sql
@@ -335,8 +335,17 @@ WITH u AS (
 UPDATE templates SET is_default=false WHERE id != $1;
 
 -- name: delete-template
--- Delete a template as long as there's more than one.
-DELETE FROM templates WHERE id=$1 AND (SELECT COUNT(id) FROM templates) > 1 AND is_default = false;
+-- Delete a template as long as there's more than one. One deletion, set all campaigns
+-- with that template to the default template instead.
+WITH tpl AS (
+    DELETE FROM templates WHERE id = $1 AND (SELECT COUNT(id) FROM templates) > 1 AND is_default = false RETURNING id
+),
+def AS (
+    SELECT id FROM templates WHERE is_default = true LIMIT 1
+)
+UPDATE campaigns SET template_id = (SELECT id FROM def) WHERE (SELECT id FROM tpl) > 0 AND template_id = $1
+    RETURNING (SELECT id FROM tpl);
+
 
 -- media
 -- name: insert-media
diff --git a/templates.go b/templates.go
index 664f4c0..c9b71e6 100644
--- a/templates.go
+++ b/templates.go
@@ -1,6 +1,7 @@
 package main
 
 import (
+	"database/sql"
 	"errors"
 	"fmt"
 	"net/http"
@@ -209,13 +210,18 @@ func handleDeleteTemplate(c echo.Context) error {
 		return echo.NewHTTPError(http.StatusBadRequest, "Cannot delete the primordial template.")
 	}
 
-	res, err := app.Queries.DeleteTemplate.Exec(id)
+	var delID int
+	err := app.Queries.DeleteTemplate.Get(&delID, id)
 	if err != nil {
+		if err == sql.ErrNoRows {
+			return c.JSON(http.StatusOK, okResp{true})
+		}
+
 		return echo.NewHTTPError(http.StatusBadRequest,
 			fmt.Sprintf("Error deleting template: %v", err))
 	}
 
-	if n, _ := res.RowsAffected(); n == 0 {
+	if delID == 0 {
 		return echo.NewHTTPError(http.StatusBadRequest,
 			"Cannot delete the last, default, or non-existent template.")
 	}