From 0f3a9a8d02f638a1af862269236bbd1f8d4ade1f Mon Sep 17 00:00:00 2001
From: Jinzhu <wosmvp@gmail.com>
Date: Mon, 8 Sep 2014 11:19:05 +0800
Subject: [PATCH] Support include struct type in the foreign key to avoid
 ambiguous

---
 scope_private.go | 60 +++++++++++++++++++++++++++++-------------------
 1 file changed, 36 insertions(+), 24 deletions(-)

diff --git a/scope_private.go b/scope_private.go
index b6949db3..209db5bb 100644
--- a/scope_private.go
+++ b/scope_private.go
@@ -419,38 +419,50 @@ func (scope *Scope) typeName() string {
 
 func (scope *Scope) related(value interface{}, foreignKeys ...string) *Scope {
 	toScope := scope.db.NewScope(value)
+	fromScopeType := scope.typeName()
+	toScopeType := toScope.typeName()
+	scopeType := ""
 
 	for _, foreignKey := range append(foreignKeys, toScope.typeName()+"Id", scope.typeName()+"Id") {
-		if field, ok := scope.FieldByName(foreignKey); ok {
-			relationship := field.Relationship
-			if relationship != nil && relationship.ForeignKey != "" {
-				foreignKey = relationship.ForeignKey
+		if keys := strings.Split(foreignKey, "."); len(keys) > 1 {
+			scopeType = keys[0]
+			foreignKey = keys[1]
+		}
 
-				if relationship.Kind == "many_to_many" {
-					joinSql := fmt.Sprintf(
-						"INNER JOIN %v ON %v.%v = %v.%v",
-						scope.Quote(relationship.JoinTable),
-						scope.Quote(relationship.JoinTable),
-						scope.Quote(ToSnake(relationship.AssociationForeignKey)),
-						toScope.QuotedTableName(),
-						scope.Quote(toScope.PrimaryKey()))
-					whereSql := fmt.Sprintf("%v.%v = ?", scope.Quote(relationship.JoinTable), scope.Quote(ToSnake(relationship.ForeignKey)))
-					toScope.db.Joins(joinSql).Where(whereSql, scope.PrimaryKeyValue()).Find(value)
+		if scopeType == "" || scopeType == fromScopeType {
+			if field, ok := scope.FieldByName(foreignKey); ok {
+				relationship := field.Relationship
+				if relationship != nil && relationship.ForeignKey != "" {
+					foreignKey = relationship.ForeignKey
+
+					if relationship.Kind == "many_to_many" {
+						joinSql := fmt.Sprintf(
+							"INNER JOIN %v ON %v.%v = %v.%v",
+							scope.Quote(relationship.JoinTable),
+							scope.Quote(relationship.JoinTable),
+							scope.Quote(ToSnake(relationship.AssociationForeignKey)),
+							toScope.QuotedTableName(),
+							scope.Quote(toScope.PrimaryKey()))
+						whereSql := fmt.Sprintf("%v.%v = ?", scope.Quote(relationship.JoinTable), scope.Quote(ToSnake(relationship.ForeignKey)))
+						toScope.db.Joins(joinSql).Where(whereSql, scope.PrimaryKeyValue()).Find(value)
+						return scope
+					}
+				}
+
+				// has one
+				if foreignValue, ok := scope.FieldValueByName(foreignKey); ok {
+					toScope.inlineCondition(foreignValue).callCallbacks(scope.db.parent.callback.queries)
 					return scope
 				}
 			}
-
-			// has one
-			if foreignValue, ok := scope.FieldValueByName(foreignKey); ok {
-				toScope.inlineCondition(foreignValue).callCallbacks(scope.db.parent.callback.queries)
-				return scope
-			}
 		}
 
-		// has many
-		if toScope.HasColumn(foreignKey) {
-			sql := fmt.Sprintf("%v = ?", scope.Quote(ToSnake(foreignKey)))
-			return toScope.inlineCondition(sql, scope.PrimaryKeyValue()).callCallbacks(scope.db.parent.callback.queries)
+		if scopeType == "" || scopeType == toScopeType {
+			// has many
+			if toScope.HasColumn(foreignKey) {
+				sql := fmt.Sprintf("%v = ?", scope.Quote(ToSnake(foreignKey)))
+				return toScope.inlineCondition(sql, scope.PrimaryKeyValue()).callCallbacks(scope.db.parent.callback.queries)
+			}
 		}
 	}
 	scope.Err(fmt.Errorf("invalid association %v", foreignKeys))