From f2c3c2b1a4f0d7cb8dbdaef0f891c60a828daf02 Mon Sep 17 00:00:00 2001
From: Martin Kleusberg <mkleusberg@gmail.com>
Date: Thu, 6 Nov 2014 18:28:28 +0100
Subject: [PATCH] Parse and save foreign key constraints

When parsing a CREATE TABLE statement read and try to parse any foreign
key constraints and save that information.
---
 src/sqlitetypes.cpp | 27 +++++++++++++++++++++++++++
 src/sqlitetypes.h   |  3 +++
 2 files changed, 30 insertions(+)

diff --git a/src/sqlitetypes.cpp b/src/sqlitetypes.cpp
index 67329672..e99159f8 100644
--- a/src/sqlitetypes.cpp
+++ b/src/sqlitetypes.cpp
@@ -190,6 +190,14 @@ QString Table::sql() const
         if(pks_found)
             sql += pk + ")";
     }
+
+    // foreign keys
+    foreach(FieldPtr f, m_fields)
+    {
+        if(!f->foreignKey().isEmpty())
+            sql += QString(",\n\tFOREIGN KEY(`%1`) REFERENCES %2").arg(f->name()).arg(f->foreignKey());
+    }
+
     sql += "\n)";
 
     // without rowid
@@ -345,6 +353,25 @@ Table CreateTableWalker::table()
                     }
                 }
                 break;
+                case sqlite3TokenTypes::FOREIGN:
+                {
+                    tc = tc->getNextSibling();  // FOREIGN
+                    tc = tc->getNextSibling();  // KEY
+                    tc = tc->getNextSibling();  // LPAREN
+                    QString column_name = identifier(tc);
+                    tc = tc->getNextSibling();  // identifier
+                    if(tc->getType() == sqlite3TokenTypes::COMMA)
+                    {
+                        // No support for composite foreign keys
+                        m_bModifySupported = false;
+                        break;
+                    }
+                    tc = tc->getNextSibling();  // RPAREN
+                    tc = tc->getNextSibling();  // REFERENCES
+
+                    tab.fields().at(tab.findField(column_name))->setForeignKey(concatTextAST(tc, true));
+                }
+                break;
                 default:
                 {
                     m_bModifySupported = false;
diff --git a/src/sqlitetypes.h b/src/sqlitetypes.h
index 80299ea4..6eff3516 100644
--- a/src/sqlitetypes.h
+++ b/src/sqlitetypes.h
@@ -42,6 +42,7 @@ public:
     void setAutoIncrement(bool autoinc) { m_autoincrement = autoinc; }
     void setPrimaryKey(bool pk) { m_primaryKey = pk; }
     void setUnique(bool u) { m_unique = u; }
+    void setForeignKey(const QString& key) { m_foreignKey = key; }
 
     bool isText() const;
     bool isInteger() const;
@@ -54,6 +55,7 @@ public:
     bool autoIncrement() const { return m_autoincrement; }
     bool primaryKey() const { return m_primaryKey; }
     bool unique() const { return m_unique; }
+    const QString& foreignKey() const { return m_foreignKey; }
 
     static QStringList Datatypes;
 private:
@@ -62,6 +64,7 @@ private:
     bool m_notnull;
     QString m_check;
     QString m_defaultvalue;
+    QString m_foreignKey;   // Even though this information is a table constraint easier for accessing and processing to store it here
     bool m_autoincrement; //! this is stored here for simplification
     bool m_primaryKey;
     bool m_unique;