Fix crash on load entries

- TODO format time properly
- TODO add Purchases table visualization

7 files changed, 305 insertions, 258 deletions

diff --git a/core/src/Model/Project.cpp b/core/src/Model/Project.cpp
index 2a79e3f..e762efb 100644
--- a/core/src/Model/Project.cpp
+++ b/core/src/Model/Project.cpp
@@ -82,11 +82,11 @@ void Project::SetName(std::string name) {
 	mName = std::move(name);
 }
 
-const TransactionDatabase& Project::GetDatabase() const {
+const TransactionModel& Project::GetTransactionsModel() const {
 	return mDb;
 }
 
-TransactionDatabase& Project::GetDatabase() {
+TransactionModel& Project::GetTransactionsModel() {
 	return mDb;
 }
 
diff --git a/core/src/Model/Project.hpp b/core/src/Model/Project.hpp
index dca10d0..748ca82 100644
--- a/core/src/Model/Project.hpp
+++ b/core/src/Model/Project.hpp
@@ -1,7 +1,7 @@
 #pragma once
 
 #include "Model/Items.hpp"
-#include "Model/TransactionDatabase.hpp"
+#include "Model/TransactionsModel.hpp"
 
 #include <json/forwards.h>
 #include <filesystem>
@@ -17,7 +17,7 @@ private:
 	std::filesystem::path mRootPath;
 	std::string mRootPathString;
 	std::string mName;
-	TransactionDatabase mDb;
+	TransactionModel mDb;
 
 public:
 	/// Load the project from a directory containing the cplt_project.json file.
@@ -27,11 +27,6 @@ public:
 	/// This function assumes the given directory will exist and is empty.
 	Project(std::filesystem::path rootPath, std::string name);
 
-	Project(const Project&) = delete;
-	Project& operator=(const Project&) = delete;
-	Project(Project&&) = default;
-	Project& operator=(Project&&) = default;
-
 	/// Path to a *directory* that contains the project file.
 	const std::filesystem::path& GetPath() const;
 	const std::string& GetPathString() const;
@@ -39,8 +34,8 @@ public:
 	const std::string& GetName() const;
 	void SetName(std::string name);
 
-	const TransactionDatabase& GetDatabase() const;
-	TransactionDatabase& GetDatabase();
+	const TransactionModel& GetTransactionsModel() const;
+	TransactionModel& GetTransactionsModel();
 
 	Json::Value Serialize();
 	void WriteToDisk();
diff --git a/core/src/Model/TransactionDatabase.cpp b/core/src/Model/TransactionDatabase.cpp
deleted file mode 100644
index 766727d..0000000
--- a/core/src/Model/TransactionDatabase.cpp
+++ /dev/null
@@ -1,160 +0,0 @@
-#include "TransactionDatabase.hpp"
-
-#include "Model/Project.hpp"
-
-#include <filesystem>
-#include <stdexcept>
-
-namespace fs = std::filesystem;
-
-SalesTable::SalesTable(TransactionDatabase& db)
-	// language=SQLite
-	: GetRowsStatement(db.GetSQLite(), R"""(
-SELECT * FROM Sales WHERE rowid >= ? AND rowid < ?
-)""")
-	// language=SQLite
-	// TODO
-	, FilterRowsStatement(db.GetSQLite(), R"""(
-)""") {
-}
-
-int SalesTable::GetEntryCont() const {
-	// TODO
-	return 0;
-}
-
-DeliveryTable::DeliveryTable(TransactionDatabase& db) {
-}
-
-PurchasesTable::PurchasesTable(TransactionDatabase& db) {
-}
-
-static std::string GetDatabaseFilePath(const Project& project) {
-	auto dbsDir = project.GetPath() / "databases";
-	fs::create_directories(dbsDir);
-
-	auto dbFile = dbsDir / "transactions.sqlite3";
-	return dbFile.string();
-}
-
-TransactionDatabase::TransactionDatabase(Project& project)
-	: mProject{ &project }
-	, mDb(GetDatabaseFilePath(project), SQLite::OPEN_READWRITE)
-	, mSales(*this)
-	, mPurchases(*this)
-	, mDeliveries(*this) {
-	// Schema
-	// - Customer: the customer item ID
-	// - Deadline: unix epoch time of order deadline
-	// - DeliveryTime: the time this order was completed (through a set of deliveries)
-	if (!mDb.tableExists("Sales")) {
-		// language=SQLite
-		mDb.exec(R"""(
-CREATE TABLE Sales(
-	INT PRIMARY KEY,
-	Customer INT,
-	Deadline DATETIME,
-	DeliveryTime DATETIME
-);
-)""");
-	}
-
-	if (!mDb.tableExists("SalesItems")) {
-		// language=SQLite
-		mDb.exec(R"""(
-CREATE TABLE SalesItems(
-	SaleId INT,
-	ItemId INT,
-	Count INT
-);
-)""");
-	}
-
-	// Schema
-	// - Factory: the factory id,
-	// - OrderTime: the time this order was made
-	// - DeliveryTime: the time this order was completed (through a set of deliveries)
-	if (!mDb.tableExists("Purchases")) {
-		// language=SQLite
-		mDb.exec(R"""(
-CREATE TABLE Purchases(
-	INT PRIMARY KEY,
-	Factory INT,
-	OrderTime DATETIME,
-	DeliveryTime DATETIME
-);
-)""");
-	}
-
-	if (!mDb.tableExists("PurchasesItems")) {
-		// language=SQLite
-		mDb.exec(R"""(
-CREATE TABLE PurchasesItems(
-	PurchaseId INT,
-	ItemId INT,
-	Count INT
-);
-)""");
-	}
-
-	// Schema
-	// - SendTime: unix epoch time of sending to delivery
-	// - ArriveTime: unix epoch time of delivery arrived at warehouse; 0 if not arrived yet
-	// - AssociatedOrder: rowid of the order that this delivery is completing (which table: Outgoing=true -> Sales, Outgoing=false -> Purchases)
-	// - Outgoing: true if the delivery is from warehouse to customer; false if the delivery is from factory to warehouse
-	if (!mDb.tableExists("Deliveries")) {
-		// language=SQLite
-		mDb.exec(R"""(
-CREATE TABLE Deliveries(
-	INT PRIMARY KEY,
-	SendTime DATETIME,
-	ArriveTime DATETIME,
-	AssociatedOrder INT,
-	Outgoing BOOLEAN
-);
-)""");
-	}
-
-	if (!mDb.tableExists("DeliveriesItems")) {
-		// language=SQLite
-		mDb.exec(R"""(
-CREATE TABLE DeliveriesItems(
-	DeliveryId INT,
-	ItemId INT,
-	Count INT
-);
-)""");
-	}
-}
-
-const SQLite::Database& TransactionDatabase::GetSQLite() const {
-	return mDb;
-}
-
-SQLite::Database& TransactionDatabase::GetSQLite() {
-	return mDb;
-}
-
-const SalesTable& TransactionDatabase::GetSales() const {
-	return mSales;
-}
-
-SalesTable& TransactionDatabase::GetSales() {
-	return mSales;
-}
-
-const PurchasesTable& TransactionDatabase::GetPurchases() const {
-	return mPurchases;
-}
-
-PurchasesTable& TransactionDatabase::GetPurchases() {
-	return mPurchases;
-}
-
-const DeliveryTable& TransactionDatabase::GetDeliveries() const {
-	return mDeliveries;
-}
-
-DeliveryTable& TransactionDatabase::GetDeliveries() {
-	return mDeliveries;
-}
diff --git a/core/src/Model/TransactionsModel.cpp b/core/src/Model/TransactionsModel.cpp
new file mode 100644
index 0000000..6035528
--- /dev/null
+++ b/core/src/Model/TransactionsModel.cpp
@@ -0,0 +1,139 @@
+#include "TransactionsModel.hpp"
+
+#include "Model/Project.hpp"
+
+#include <filesystem>
+#include <stdexcept>
+
+namespace fs = std::filesystem;
+
+SalesTable::SalesTable(TransactionModel& db)
+	// language=SQLite
+	: GetRowsStatement(db.GetSQLite(), R"""(
+SELECT * FROM Sales WHERE rowid >= ? AND rowid < ?
+)""")
+	// language=SQLite
+	// TODO
+	, FilterRowsStatement(db.GetSQLite(), R"""(
+)""") {
+}
+
+DeliveryTable::DeliveryTable(TransactionModel& db) {
+}
+
+PurchasesTable::PurchasesTable(TransactionModel& db) {
+}
+
+static std::string GetDatabaseFilePath(const Project& project) {
+	auto dbsDir = project.GetPath() / "databases";
+	fs::create_directories(dbsDir);
+
+	auto dbFile = dbsDir / "transactions.sqlite3";
+	return dbFile.string();
+}
+
+/// Wrapper for SQLite::Database that creates the default tables
+TransactionModel::DatabaseWrapper::DatabaseWrapper(TransactionModel& self)
+	: mSqlite(GetDatabaseFilePath(*self.mProject), SQLite::OPEN_READWRITE) {
+
+	// If this table doesn't exist, the database probably just got initialized
+	if (mSqlite.tableExists("Sales")) {
+		return;
+	}
+
+	// 'Sales' schema
+	// - Customer: the customer item ID
+	// - Deadline: unix epoch time of order deadline
+	// - DeliveryTime: the time this order was completed (through a set of deliveries)
+
+	// 'Purchases' schema
+	// - Factory: the factory id,
+	// - OrderTime: the time this order was made
+	// - DeliveryTime: the time this order was completed (through a set of deliveries)
+
+	// 'Deliveries' schema
+	// - SendTime: unix epoch time of sending to delivery
+	// - ArriveTime: unix epoch time of delivery arrived at warehouse; 0 if not arrived yet
+	// - AssociatedOrder: rowid of the order that this delivery is completing (which table: Outgoing=true -> Sales, Outgoing=false -> Purchases)
+	// - Outgoing: true if the delivery is from warehouse to customer; false if the delivery is from factory to warehouse
+
+	// language=SQLite
+	mSqlite.exec(R"""(
+CREATE TABLE IF NOT EXISTS Sales(
+	INT PRIMARY KEY,
+	Customer INT,
+	Deadline DATETIME,
+	DeliveryTime DATETIME
+);
+CREATE TABLE IF NOT EXISTS SalesItems(
+	SaleId INT,
+	ItemId INT,
+	Count INT
+);
+
+CREATE TABLE IF NOT EXISTS Purchases(
+    INT PRIMARY KEY,
+    Factory INT,
+    OrderTime DATETIME,
+    DeliveryTime DATETIME
+);
+CREATE TABLE IF NOT EXISTS PurchasesItems(
+     PurchaseId INT,
+     ItemId INT,
+     Count INT
+);
+
+CREATE TABLE IF NOT EXISTS Deliveries(
+     INT PRIMARY KEY,
+     SendTime DATETIME,
+     ArriveTime DATETIME,
+     AssociatedOrder INT,
+     Outgoing BOOLEAN
+);
+CREATE TABLE IF NOT EXISTS DeliveriesItems(
+      DeliveryId INT,
+      ItemId INT,
+      Count INT
+);
+)""");
+}
+
+TransactionModel::TransactionModel(Project& project)
+	: mProject{ &project }
+	, mDbWrapper(*this)
+	, mSales(*this)
+	, mPurchases(*this)
+	, mDeliveries(*this) {
+}
+
+const SQLite::Database& TransactionModel::GetSQLite() const {
+	return mDbWrapper.mSqlite;
+}
+
+SQLite::Database& TransactionModel::GetSQLite() {
+	return mDbWrapper.mSqlite;
+}
+
+const SalesTable& TransactionModel::GetSales() const {
+	return mSales;
+}
+
+SalesTable& TransactionModel::GetSales() {
+	return mSales;
+}
+
+const PurchasesTable& TransactionModel::GetPurchases() const {
+	return mPurchases;
+}
+
+PurchasesTable& TransactionModel::GetPurchases() {
+	return mPurchases;
+}
+
+const DeliveryTable& TransactionModel::GetDeliveries() const {
+	return mDeliveries;
+}
+
+DeliveryTable& TransactionModel::GetDeliveries() {
+	return mDeliveries;
+}
diff --git a/core/src/Model/TransactionDatabase.hpp b/core/src/Model/TransactionsModel.hpp
index 9c869c4..beed663 100644
--- a/core/src/Model/TransactionDatabase.hpp
+++ b/core/src/Model/TransactionsModel.hpp
@@ -12,31 +12,36 @@ public:
 	SQLite::Statement FilterRowsStatement;
 
 public:
-	SalesTable(TransactionDatabase& db);
-
-	int GetEntryCont() const;
+	SalesTable(TransactionModel& db);
 };
 
 class PurchasesTable {
 public:
-	PurchasesTable(TransactionDatabase& db);
+	PurchasesTable(TransactionModel& db);
 };
 
 class DeliveryTable {
 public:
-	DeliveryTable(TransactionDatabase& db);
+	DeliveryTable(TransactionModel& db);
 };
 
-class TransactionDatabase {
+// TODO fuck SQLite::Statement has move ctor but not move assignment operator
+class TransactionModel {
 private:
+	class DatabaseWrapper {
+	public:
+		SQLite::Database mSqlite;
+		DatabaseWrapper(TransactionModel& self);
+	};
+
 	Project* mProject;
-	SQLite::Database mDb;
+	DatabaseWrapper mDbWrapper;
 	SalesTable mSales;
 	PurchasesTable mPurchases;
 	DeliveryTable mDeliveries;
 
 public:
-	TransactionDatabase(Project& project);
+	TransactionModel(Project& project);
 
 	const SQLite::Database& GetSQLite() const;
 	SQLite::Database& GetSQLite();
@@ -46,5 +51,5 @@ public:
 	const PurchasesTable& GetPurchases() const;
 	PurchasesTable& GetPurchases();
 	const DeliveryTable& GetDeliveries() const;
-	DeliveryTable& GetDeliveries()
+	DeliveryTable& GetDeliveries();
 };
diff --git a/core/src/Model/fwd.hpp b/core/src/Model/fwd.hpp
index e153923..4bd508c 100644
--- a/core/src/Model/fwd.hpp
+++ b/core/src/Model/fwd.hpp
@@ -22,4 +22,4 @@ class Project;
 class SalesTable;
 class PurchasesTable;
 class DeliveryTable;
-class TransactionDatabase;
+class TransactionModel;
diff --git a/core/src/UI/UI_DatabaseView.cpp b/core/src/UI/UI_DatabaseView.cpp
index 2b74918..8791c5b 100644
--- a/core/src/UI/UI_DatabaseView.cpp
+++ b/core/src/UI/UI_DatabaseView.cpp
@@ -1,5 +1,6 @@
 #include "UI.hpp"
 
+#include "Model/Filter.hpp"
 #include "Model/Project.hpp"
 #include "UI/Localization.hpp"
 #include "UI/States.hpp"
@@ -10,6 +11,7 @@
 #include <SQLiteCpp/Statement.h>
 #include <imgui.h>
 #include <cstdint>
+#include <ctime>
 #include <memory>
 #include <vector>
 
@@ -25,6 +27,13 @@ public:
 	std::string DeliveryTime;
 };
 
+class PurchaseEntry {
+public:
+	std::string Factory;
+	std::string OrderTime;
+	std::string DeliveryTime;
+};
+
 class SalesViewTab {
 private:
 	Project* mProject;
@@ -42,38 +51,63 @@ private:
 	/// A cached, contiguous (row id of each entry is monotonically increasing, but not necessarily starts at 0) list ready-to-be-presented entries. May be incomplete.
 	std::vector<SaleEntry> mEntries;
 
-	// TODO this is very impractical (running filter in client code instead of letting SQLite doing it)
-	// Maybe simply cache a list of indices produced by a sql query?
-
-	/// A bitset of all active (should-be-displayed) entries based on current filter, updated whenever \c mActiveFilter is updated.
-	/// Should have the exact same size as \c entries.
-	std::vector<bool> mActiveEntries;
-
-	/// A cached list of index to entries that should be displayed on the current page.
-	std::vector<int> mCurrentPageEntries;
+	/// A vector of row ids of entries (in \c mEntries) that are visible under the current filter. To use these indices, the elements should be mapped to \c mEntries
+	/// index by offsetting by \c mFirstCachedRowId.
+	std::vector<int> mActiveEntries;
 
-	/// The current page the user is on.
-	int mCurrentPage;
 	/// Last possible page for the current set table and filter (inclusive).
 	int mLastPage;
+	/// The current page the user is on.
+	int mCurrentPage;
 
-	/* UI states */
-
-	int mSelectedEntry;
+	int mSelectedEntryRowId;
 
 public:
+	Project* GetProject() const {
+		return mProject;
+	}
+
 	void OnProjectChanged(Project* newProject) {
 		mProject = newProject;
 
+		mFirstCachedRowId = 0;
+		mLastCachedRowId = 0;
+
 		mEntries.clear();
-		mCurrentPage = 0;
-		mLastPage = -1;
+		mActiveEntries.clear();
+
+		UpdateLastPage();
+		SetPage(0);
 
-		mSelectedEntry = -1;
+		mSelectedEntryRowId = -1;
+	}
+
+	TableRowsFilter* GetFilter() const {
+		return mActiveFilter.get();
+	}
+
+	void OnFilterChanged() {
+		auto& stmt = mProject->GetTransactionsModel().GetSales().FilterRowsStatement;
+		DEFER {
+			stmt.reset();
+		};
+
+		// TODO lazy loading when too many results
+		mActiveEntries.clear();
+		int columnIdx = stmt.getColumnIndex("rowid");
+		while (stmt.executeStep()) {
+			mActiveEntries.push_back(stmt.getColumn(columnIdx).getInt());
+		}
+
+		UpdateLastPage();
+		SetPage(0);
+
+		mSelectedEntryRowId = -1;
 	}
 
 	void OnFilterChanged(std::unique_ptr<TableRowsFilter> filter) {
-		// TODO
+		mActiveFilter = std::move(filter);
+		OnFilterChanged();
 	}
 
 	void Draw() {
@@ -94,7 +128,7 @@ public:
 		}
 
 		ImGui::SameLine();
-		if (ImGui::Button(ls->Edit.Get(), mSelectedEntry == -1)) {
+		if (ImGui::Button(ls->Edit.Get(), mSelectedEntryRowId == -1)) {
 			ImGui::OpenPopup(ls->EditSaleEntryDialogTitle.Get());
 		}
 		if (ImGui::BeginPopupModal(ls->EditSaleEntryDialogTitle.Get(), &dummy, ImGuiWindowFlags_AlwaysAutoResize)) {
@@ -109,22 +143,17 @@ public:
 			ImGui::TableSetupColumn(ls->DatabaseDeliveryTimeColumn.Get());
 			ImGui::TableHeadersRow();
 
-			for (int i : mCurrentPageEntries) {
-				auto& entry = mEntries[i];
-
-				ImGui::TableNextColumn();
-				if (ImGui::Selectable(entry.Customer.c_str(), mSelectedEntry == i)) {
-					mSelectedEntry = i;
+			auto [begin, end] = CalcRangeForPage(mCurrentPage);
+			if (mActiveFilter) {
+				end = std::min(end, (int64_t)mActiveEntries.size() - 1);
+				for (int i = begin; i < end; ++i) {
+					int rowId = mActiveEntries[i];
+					DrawEntry(GetEntry(rowId), rowId);
 				}
-
-				ImGui::NextColumn();
-				ImGui::Text("%s", entry.Deadline.c_str());
-
-				ImGui::NextColumn();
-				if (entry.DeliveryTime.empty()) {
-					ImGui::Text("%s", ls->NotDeliveredMessage.Get());
-				} else {
-					ImGui::Text("%s", entry.DeliveryTime.c_str());
+			} else {
+				end = std::min(end, mLastCachedRowId);
+				for (int rowId = begin; rowId < end; ++rowId) {
+					DrawEntry(GetEntry(rowId), rowId);
 				}
 			}
 
@@ -132,23 +161,43 @@ public:
 		}
 	}
 
+	void DrawEntry(const SaleEntry& entry, int rowId) {
+		auto ls = LocaleStrings::Instance.get();
+
+		ImGui::TableNextColumn();
+		if (ImGui::Selectable(entry.Customer.c_str(), mSelectedEntryRowId == rowId, ImGuiSelectableFlags_SpanAllColumns)) {
+			mSelectedEntryRowId = rowId;
+		}
+
+		ImGui::TableNextColumn();
+		ImGui::Text("%s", entry.Deadline.c_str());
+
+		ImGui::TableNextColumn();
+		if (entry.DeliveryTime.empty()) {
+			ImGui::Text("%s", ls->NotDeliveredMessage.Get());
+		} else {
+			ImGui::Text("%s", entry.DeliveryTime.c_str());
+		}
+	}
+
+	const SaleEntry& GetEntry(int64_t rowId) const {
+		return mEntries[RowIdToIndex(rowId)];
+	}
+
+	SaleEntry& GetEntry(int64_t rowId) {
+		return mEntries[RowIdToIndex(rowId)];
+	}
+
 private:
 	void SetPage(int page) {
-		if (mCurrentPage != page) return;
-
 		mCurrentPage = page;
 		EnsureCacheCoversPage(page);
+	}
 
-		auto [begin, end] = CalcRangeForPage(page);
-		begin -= mFirstCachedRowId;
-		end -= mFirstCachedRowId;
-
-		mCurrentPageEntries.clear();
-		for (auto i = begin; i < end; ++i) {
-			if (mActiveEntries[i]) {
-				mCurrentPageEntries.push_back(i);
-			}
-		}
+	void UpdateLastPage() {
+		mLastPage = mActiveEntries.empty()
+			? 0
+			: CalcPageForRowId(mActiveEntries.back());
 	}
 
 	void EnsureCacheCoversPage(int page) {
@@ -166,11 +215,11 @@ private:
 
 		bool doRebuild = false;
 		if (firstRow < mFirstCachedRowId) {
-			newFirst = CalcPageForRowId(firstRow) * kMaxEntriesPerPage;
+			newFirst = (CalcPageForRowId(firstRow) + 1) * kMaxEntriesPerPage;
 			doRebuild = true;
 		}
 		if (lastRow > mLastCachedRowId) {
-			newLast = CalcPageForRowId(lastRow) * kMaxEntriesPerPage;
+			newLast = (CalcPageForRowId(lastRow) + 1) * kMaxEntriesPerPage;
 			doRebuild = true;
 		}
 		if (!doRebuild) return;
@@ -178,12 +227,12 @@ private:
 		auto front = LoadRange(newFirst, mFirstCachedRowId);
 		auto back = LoadRange(mLastCachedRowId + 1, newLast + 1);
 
-		mEntries.insert(mEntries.begin(), front.begin(), front.end());
-		mEntries.insert(mEntries.end(), back.begin(), back.end());
-		// TODO update mActiveEntries
+		mFirstCachedRowId -= front.size();
+		mLastCachedRowId += back.size();
 
-		mFirstCachedRowId = newFirst;
-		mLastCachedRowId = newLast;
+		// TODO don't reallocate buffer/move elements around all the time. Maybe use a linked list of buckets?
+		mEntries.insert(mEntries.begin(), std::make_move_iterator(front.begin()), std::make_move_iterator(front.end()));
+		mEntries.insert(mEntries.end(), std::make_move_iterator(back.begin()), std::make_move_iterator(back.end()));
 	}
 
 	std::vector<SaleEntry> LoadRange(int64_t begin, int64_t end) {
@@ -196,7 +245,7 @@ private:
 
 		result.reserve(size);
 
-		auto& stmt = mProject->GetDatabase().GetSales().GetRowsStatement;
+		auto& stmt = mProject->GetTransactionsModel().GetSales().GetRowsStatement;
 		DEFER {
 			stmt.reset();
 		};
@@ -204,34 +253,54 @@ private:
 		stmt.bind(1, begin);
 		stmt.bind(2, end);
 
-		while (true) {
-			bool hasResult = stmt.executeStep();
-			if (hasResult) {
-				result.push_back(stmt.getColumns<SaleEntry, 3>());
-			} else {
-				return result;
+		auto StringifyEpochTime = [](int64_t epoch) -> std::string {
+			if (epoch == 0) {
+				return "";
 			}
+
+			auto t = static_cast<time_t>(epoch);
+			std::string str(29, '\0');
+			std::strftime(str.data(), 21, "%Y-%m-%dT%H:%M:%S.", std::localtime(&t));
+			return str;
+		};
+
+		int customerCol = stmt.getColumnIndex("Customer");
+		int deadlineCol = stmt.getColumnIndex("Deadline");
+		int deliveryTimeCol = stmt.getColumnIndex("DeliveryTime");
+
+		while (stmt.executeStep()) {
+			auto customer = stmt.getColumn(customerCol).getInt();
+			auto deadline = stmt.getColumn(deadlineCol).getInt64();
+			auto deliveryTime = stmt.getColumn(deliveryTimeCol).getInt64();
+			result.push_back(SaleEntry{
+				.Customer = mProject->Customers.Find(customer)->GetName(),
+				.Deadline = StringifyEpochTime(deadline),
+				.DeliveryTime = StringifyEpochTime(deliveryTime),
+			});
 		}
+		return result;
+	}
+
+	int RowIdToIndex(int64_t rowId) const {
+		return rowId - mFirstCachedRowId;
+	}
+
+	int64_t IndexToRowId(int index) const {
+		return index + mFirstCachedRowId;
 	}
 
 	static int CalcPageForRowId(int64_t rowId) {
 		return rowId / kMaxEntriesPerPage;
 	}
 
-	/// Calculate range [begin, end) of row ids that the path-th page would show.
+	/// Calculate range [begin, end) of index for the list of entries that are currently visible that the path-th page would show.
+	/// i.e. when there is a filter, look into \c mActiveEntryIndices; when there is no filter, use directly.
 	static std::pair<int64_t, int64_t> CalcRangeForPage(int page) {
 		int begin = page * kMaxEntriesPerPage;
 		return { begin, begin + kMaxEntriesPerPage };
 	}
 };
 
-class PurchaseEntry {
-public:
-	std::string Factory;
-	std::string OrderTime;
-	std::string DeliveryTime;
-};
-
 class PurchasesViewTab {
 private:
 	std::vector<PurchaseEntry> mEntries;
@@ -256,26 +325,25 @@ void UI::DatabaseViewTab() {
 	auto& uis = UIState::GetInstance();
 
 	static Project* currentProject = nullptr;
-	static auto salesView = std::make_unique<SalesViewTab>();
-	static auto purchasesView = std::make_unique<PurchasesViewTab>();
+	static SalesViewTab salesView;
+	static PurchasesViewTab purchasesView;
 
 	if (currentProject != uis.CurrentProject.get()) {
 		currentProject = uis.CurrentProject.get();
-		salesView->OnProjectChanged(currentProject);
-		purchasesView->OnProjectChanged(currentProject);
+		salesView.OnProjectChanged(currentProject);
+		purchasesView.OnProjectChanged(currentProject);
 	}
 
 	if (ImGui::BeginTabBar("##DatabaseViewTabs")) {
 		if (ImGui::BeginTabItem(ls->SalesViewTab.Get())) {
-			salesView->Draw();
+			salesView.Draw();
 			ImGui::EndTabItem();
 		}
 		if (ImGui::BeginTabItem(ls->PurchasesViewTab.Get())) {
-			purchasesView->Draw();
+			purchasesView.Draw();
 			ImGui::EndTabItem();
 		}
-		//		if (ImGui::BeginTabItem(ls->DeliveriesTableTab.Get())) {
-		//			ImGui::EndTabItem();
-		//		}
+
+		ImGui::EndTabBar();
 	}
 }