From 52bc00a5ade94268037d209d673ec03e0349d49b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Hugo=20Beauz=C3=A9e-Luyssen?= <hugo@beauzee.fr>
Date: Mon, 28 Dec 2015 16:08:46 +0100
Subject: [PATCH] Folder: Simplify full path reconstruction

Relying on the fact that we only use a specific set of getters is not
future proof at all.
Also, this is using lazy loading instead of a fairly heavy overhead each
time we fetch all the folders
---
 src/Folder.cpp | 40 ++++++++++++----------------------------
 src/Folder.h   |  7 +++----
 2 files changed, 15 insertions(+), 32 deletions(-)

diff --git a/src/Folder.cpp b/src/Folder.cpp
index 859f4336..7b311faa 100644
--- a/src/Folder.cpp
+++ b/src/Folder.cpp
@@ -100,7 +100,7 @@ std::shared_ptr<Folder> Folder::create( DBConnection connection, const std::stri
         return nullptr;
     self->m_dbConection = connection;
     self->m_deviceMountpoint = deviceFs.mountpoint();
-    self->computeFullPath();
+    self->m_fullPath = self->m_deviceMountpoint.get() + path;
     return self;
 }
 
@@ -146,7 +146,7 @@ std::shared_ptr<Folder> Folder::fromPath( DBConnection conn, const std::string&
     if ( folder == nullptr )
         return nullptr;
     folder->m_deviceMountpoint = deviceFs->mountpoint();
-    folder->computeFullPath();
+    folder->m_fullPath = folder->m_deviceMountpoint.get() + path;
     return folder;
 }
 
@@ -157,6 +157,14 @@ unsigned int Folder::id() const
 
 const std::string& Folder::path() const
 {
+    auto lock = m_deviceMountpoint.lock();
+    if ( m_deviceMountpoint.isCached() == true )
+        return m_fullPath;
+
+    auto device = Device::fetch( m_dbConection, m_deviceId );
+    auto deviceFs = FsFactory->createDevice( device->uuid() );
+    m_deviceMountpoint = deviceFs->mountpoint();
+    m_fullPath = m_deviceMountpoint.get() + m_path;
     return m_fullPath;
 }
 
@@ -202,42 +210,18 @@ bool Folder::isPresent() const
     return m_isPresent;
 }
 
-void Folder::computeFullPath()
-{
-    if ( ( *m_deviceMountpoint.crbegin() ) != '/' )
-        m_deviceMountpoint += '/';
-    m_fullPath = m_deviceMountpoint + m_path;
-}
-
 std::vector<std::shared_ptr<Folder>> Folder::fetchAll( DBConnection dbConn, unsigned int parentFolderId )
 {
-    std::vector<std::shared_ptr<Folder>> res;
     if ( parentFolderId == 0 )
     {
         static const std::string req = "SELECT * FROM " + policy::FolderTable::Name
                 + " WHERE id_parent IS NULL AND is_blacklisted is NULL";
-        res = DatabaseHelpers::fetchAll<Folder>( dbConn, req );
+        return DatabaseHelpers::fetchAll<Folder>( dbConn, req );
     }
     else
     {
         static const std::string req = "SELECT * FROM " + policy::FolderTable::Name
                 + " WHERE id_parent = ? AND is_blacklisted is NULL";
-        res = DatabaseHelpers::fetchAll<Folder>( dbConn, req, parentFolderId );
-    }
-    std::unordered_map<unsigned int, std::string> deviceMountpoints;
-    for ( auto& f : res )
-    {
-        auto it = deviceMountpoints.find( f->deviceId() );
-        if ( it == end( deviceMountpoints ) )
-        {
-            auto device = Device::fetch( dbConn, f->deviceId() );
-            auto deviceFs = FsFactory->createDevice( device->uuid() );
-            deviceMountpoints[f->deviceId()] = deviceFs->mountpoint();
-            f->m_deviceMountpoint = deviceFs->mountpoint();
-        }
-        else
-            f->m_deviceMountpoint = it->second;
-        f->computeFullPath();
+        return DatabaseHelpers::fetchAll<Folder>( dbConn, req, parentFolderId );
     }
-    return res;
 }
diff --git a/src/Folder.h b/src/Folder.h
index 44ca3400..13156bc7 100644
--- a/src/Folder.h
+++ b/src/Folder.h
@@ -24,6 +24,7 @@
 
 #include "database/DatabaseHelpers.h"
 #include "factory/IFileSystem.h"
+#include "utils/Cache.h"
 
 #include <sqlite3.h>
 
@@ -79,8 +80,6 @@ public:
     bool isPresent() const;
 
 private:
-    void computeFullPath();
-
     static std::shared_ptr<factory::IFileSystem> FsFactory;
 
 private:
@@ -95,9 +94,9 @@ private:
     unsigned int m_deviceId;
     bool m_isPresent;
 
-    std::string m_deviceMountpoint;
+    mutable Cache<std::string> m_deviceMountpoint;
     // This contains the full path, including device mountpoint.
-    std::string m_fullPath;
+    mutable std::string m_fullPath;
 
     friend struct policy::FolderTable;
 };
-- 
2.22.0