From 82412ace20834c311fc8a08cb595092ebc33f14d Mon Sep 17 00:00:00 2001
From: hptruong93 <hptruong93@gmail.com>
Date: Mon, 23 May 2022 15:15:53 -0400
Subject: [PATCH] Add logic to handle task source history. Starting without any
 storage yet.

---
 .../userDefinedTask/TaskSourceManager.java    |  4 +-
 .../userDefinedTask/UserDefinedAction.java    | 14 +++++
 .../internals/TaskSourceHistory.java          | 46 ++++++++++++++++
 .../internals/TaskSourceHistoryEntry.java     | 26 +++++++++
 src/core/webui/server/UIServer.java           |  2 +
 .../internals/tasks/GetTaskSourceHandler.java | 53 +++++++++++++++++++
 .../RenderedDetailedUserDefinedAction.java    | 14 +++++
 .../RenderedTaskSourceHistory.java            | 21 ++++++++
 .../RenderedTaskSourceHistoryEntry.java       | 28 ++++++++++
 src/frontEnd/MainBackEndHolder.java           | 11 ++++
 .../fragments/task_source_history.ftlh        | 16 ++++++
 .../webui/templates/task_details.ftlh         |  2 +
 12 files changed, 236 insertions(+), 1 deletion(-)
 create mode 100644 src/core/userDefinedTask/internals/TaskSourceHistory.java
 create mode 100644 src/core/userDefinedTask/internals/TaskSourceHistoryEntry.java
 create mode 100644 src/core/webui/server/handlers/internals/tasks/GetTaskSourceHandler.java
 create mode 100644 src/core/webui/server/handlers/renderedobjects/RenderedTaskSourceHistory.java
 create mode 100644 src/core/webui/server/handlers/renderedobjects/RenderedTaskSourceHistoryEntry.java
 create mode 100644 src/staticContent/webui/templates/fragments/task_source_history.ftlh

diff --git a/src/core/userDefinedTask/TaskSourceManager.java b/src/core/userDefinedTask/TaskSourceManager.java
index 4da2a501..d20e71b5 100644
--- a/src/core/userDefinedTask/TaskSourceManager.java
+++ b/src/core/userDefinedTask/TaskSourceManager.java
@@ -26,7 +26,9 @@ public static boolean submitTask(UserDefinedAction task, String source) {
 			return false;
 		}
 
-		task.setSourcePath(FileUtility.getRelativePwdPath(sourceFile));
+		String relativePath = FileUtility.getRelativePwdPath(sourceFile);
+		task.setSourcePath(relativePath);
+		task.recordSourceHistory(relativePath);
 		return true;
 	}
 
diff --git a/src/core/userDefinedTask/UserDefinedAction.java b/src/core/userDefinedTask/UserDefinedAction.java
index e5957e09..d2624a61 100644
--- a/src/core/userDefinedTask/UserDefinedAction.java
+++ b/src/core/userDefinedTask/UserDefinedAction.java
@@ -18,6 +18,8 @@
 import core.languageHandler.compiler.AbstractNativeCompiler;
 import core.languageHandler.compiler.DynamicCompilerManager;
 import core.languageHandler.compiler.RemoteRepeatsCompiler;
+import core.userDefinedTask.internals.TaskSourceHistory;
+import core.userDefinedTask.internals.TaskSourceHistoryEntry;
 import utilities.FileUtility;
 import utilities.ILoggable;
 import utilities.json.IJsonable;
@@ -39,7 +41,9 @@ public abstract class UserDefinedAction implements IJsonable, ILoggable {
 
 	// This is to enable invoking task programmatically.
 	protected TaskInvoker taskInvoker;
+
 	protected UsageStatistics statistics;
+	protected TaskSourceHistory sourceHistory;
 
 	public UserDefinedAction() {
 		this(UUID.randomUUID().toString());
@@ -51,6 +55,7 @@ protected UserDefinedAction(String actionId) {
 		invoker = TaskActivation.newBuilder().build();
 		invokingKeyChain = new KeyChain();
 		statistics = new UsageStatistics();
+		sourceHistory = new TaskSourceHistory();
 		enabled = true;
 	}
 
@@ -123,6 +128,10 @@ public final void setSourcePath(String sourcePath) {
 		this.sourcePath = sourcePath;
 	}
 
+	public final void recordSourceHistory(String sourcePath) {
+		sourceHistory.addEntry(TaskSourceHistoryEntry.of(sourcePath));
+	}
+
 	public final Language getCompiler() {
 		return compiler;
 	}
@@ -151,10 +160,15 @@ public final UsageStatistics getStatistics() {
 		return statistics;
 	}
 
+	public final TaskSourceHistory getTaskSourceHistory() {
+		return sourceHistory;
+	}
+
 	public final void override(UserDefinedAction other) {
 		setName(other.getName());
 		activation.copy(other.activation);
 		statistics = other.statistics;
+		sourceHistory.addHistory(other.sourceHistory);
 	}
 
 	/**
diff --git a/src/core/userDefinedTask/internals/TaskSourceHistory.java b/src/core/userDefinedTask/internals/TaskSourceHistory.java
new file mode 100644
index 00000000..2594e5b7
--- /dev/null
+++ b/src/core/userDefinedTask/internals/TaskSourceHistory.java
@@ -0,0 +1,46 @@
+package core.userDefinedTask.internals;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+/** Contains information about the source history of a task. */
+public class TaskSourceHistory {
+
+	private List<TaskSourceHistoryEntry> entries;
+
+	public TaskSourceHistory() {
+		this.entries = new ArrayList<>();
+	}
+
+	/**
+	 * Finds a particular entry given the timestamp.
+	 *
+	 * @param timestamp the timestamp to find the entry for.
+	 * @return the found entry, or null if no entry was found.
+	 */
+	public TaskSourceHistoryEntry findEntry(long timestamp) {
+		for (TaskSourceHistoryEntry entry : entries) {
+			if (entry.getCreated().getTimeInMillis() == timestamp) {
+				return entry;
+			}
+		}
+		return null;
+	}
+
+	// Adds a single entry to the history.
+	public void addEntry(TaskSourceHistoryEntry entry) {
+		this.entries.add(entry);
+	}
+
+	/// Adds all history to this history.
+	public void addHistory(TaskSourceHistory history) {
+		entries.addAll(history.entries);
+		entries.sort((e1, e2) -> e2.getCreated().compareTo(e1.getCreated()));
+	}
+
+	// Returns the list of entries sorted in reverse chronological order.
+	public List<TaskSourceHistoryEntry> getEntries() {
+		return entries.stream().sorted((e1, e2) -> e2.getCreated().compareTo(e1.getCreated())).collect(Collectors.toList());
+	}
+}
diff --git a/src/core/userDefinedTask/internals/TaskSourceHistoryEntry.java b/src/core/userDefinedTask/internals/TaskSourceHistoryEntry.java
new file mode 100644
index 00000000..e86b6532
--- /dev/null
+++ b/src/core/userDefinedTask/internals/TaskSourceHistoryEntry.java
@@ -0,0 +1,26 @@
+package core.userDefinedTask.internals;
+
+import java.util.Calendar;
+
+/** Holds a single entry of source history. */
+public class TaskSourceHistoryEntry {
+	private String sourcePath;
+	private Calendar created;
+
+	private TaskSourceHistoryEntry(String sourcePath, Calendar created) {
+		this.sourcePath = sourcePath;
+		this.created = created;
+	}
+
+	public static TaskSourceHistoryEntry of(String path) {
+		return new TaskSourceHistoryEntry(path, Calendar.getInstance());
+	}
+
+	public String getSourcePath() {
+		return sourcePath;
+	}
+
+	public Calendar getCreated() {
+		return created;
+	}
+}
diff --git a/src/core/webui/server/UIServer.java b/src/core/webui/server/UIServer.java
index 4345042d..5a89d129 100644
--- a/src/core/webui/server/UIServer.java
+++ b/src/core/webui/server/UIServer.java
@@ -111,6 +111,7 @@
 import core.webui.server.handlers.internals.taskmanagement.GetRenderedTaskGroupsSelectModalHandler;
 import core.webui.server.handlers.internals.tasks.ActionSaveTaskActivationHandler;
 import core.webui.server.handlers.internals.tasks.GetRunTaskConfigHandler;
+import core.webui.server.handlers.internals.tasks.GetTaskSourceHandler;
 import core.webui.server.handlers.internals.tasks.ModifyTaskNameHandler;
 import core.webui.server.handlers.internals.tasks.RunTaskHandler;
 import core.webui.server.handlers.internals.tasks.SaveRunTaskConfigHandler;
@@ -277,6 +278,7 @@ private Map<String, HttpHandlerWithBackend> createHandlers() {
 		output.put("/internals/get/mouse-position", new GetMousePositionHandler());
 		output.put("/internals/get/path-suggestion", new GetPathSuggestionHandler());
 		output.put("/internals/get/source-templates", new GetSourceTemplateHandler());
+		output.put("/internals/get/task-source", new GetTaskSourceHandler());
 		output.put("/internals/get/rendered-task-groups-dropdown", new GetRenderedTaskGroupsDropdown(objectRenderer));
 		output.put("/internals/get/rendered-task-groups-select-modal", new GetRenderedTaskGroupsSelectModalHandler(objectRenderer));
 
diff --git a/src/core/webui/server/handlers/internals/tasks/GetTaskSourceHandler.java b/src/core/webui/server/handlers/internals/tasks/GetTaskSourceHandler.java
new file mode 100644
index 00000000..355e9681
--- /dev/null
+++ b/src/core/webui/server/handlers/internals/tasks/GetTaskSourceHandler.java
@@ -0,0 +1,53 @@
+package core.webui.server.handlers.internals.tasks;
+
+import java.io.IOException;
+import java.util.Map;
+
+import org.apache.http.HttpException;
+import org.apache.http.HttpRequest;
+import org.apache.http.nio.protocol.HttpAsyncExchange;
+import org.apache.http.protocol.HttpContext;
+
+import core.userDefinedTask.UserDefinedAction;
+import core.webui.server.handlers.AbstractSingleMethodHttpHandler;
+import core.webui.webcommon.HttpServerUtilities;
+
+public class GetTaskSourceHandler extends AbstractSingleMethodHttpHandler {
+
+	public GetTaskSourceHandler() {
+		super(AbstractSingleMethodHttpHandler.GET_METHOD);
+	}
+
+	@Override
+	protected Void handleAllowedRequestWithBackend(HttpRequest request, HttpAsyncExchange exchange, HttpContext context)
+			throws HttpException, IOException {
+		String uriString = request.getRequestLine().getUri();
+		Map<String, String>  params = HttpServerUtilities.parseGetParameters(uriString);
+		if (params == null) {
+			return HttpServerUtilities.prepareHttpResponse(exchange, 500, "Failed to parse URL " + uriString);
+		}
+
+		String id = params.get("id");
+		if (id == null || id.isEmpty()) {
+			return HttpServerUtilities.prepareHttpResponse(exchange, 400, "Task ID is empty or not provided.");
+		}
+
+		String timestampString = params.get("timestamp");
+		if (timestampString == null || timestampString.isEmpty()) {
+			return HttpServerUtilities.prepareHttpResponse(exchange, 400, "Timestamp is empty or not provided.");
+		}
+
+		UserDefinedAction action = backEndHolder.getTask(id);
+		if (action == null) {
+			return HttpServerUtilities.prepareHttpResponse(exchange, 404, "No action for ID " + id + ".");
+		}
+
+		Long timestamp = Long.parseLong(timestampString);
+		String sourceCode = backEndHolder.getSourceForTask(action, timestamp);
+		if (sourceCode == null) {
+			return HttpServerUtilities.prepareHttpResponse(exchange, 500, "No source code found for task " + id + ".");
+		}
+
+		return HttpServerUtilities.prepareTextResponse(exchange, 200, sourceCode);
+	}
+}
diff --git a/src/core/webui/server/handlers/renderedobjects/RenderedDetailedUserDefinedAction.java b/src/core/webui/server/handlers/renderedobjects/RenderedDetailedUserDefinedAction.java
index 6f7e283d..506049f7 100644
--- a/src/core/webui/server/handlers/renderedobjects/RenderedDetailedUserDefinedAction.java
+++ b/src/core/webui/server/handlers/renderedobjects/RenderedDetailedUserDefinedAction.java
@@ -10,6 +10,8 @@ public class RenderedDetailedUserDefinedAction {
 	private RenderedTaskActivation activation;
 	private String hasStatistics;
 	private RenderedUserDefinedActionStatistics statistics;
+	private String hasSourceHistory;
+	private RenderedTaskSourceHistory sourceHistory;
 
 	private RenderedDetailedUserDefinedAction() {}
 
@@ -21,6 +23,8 @@ public static RenderedDetailedUserDefinedAction withEmptyTaskInfo(TaskActivation
 		result.activation = RenderedTaskActivation.fromActivation(activationConstructor);
 		result.hasStatistics = false + "";
 		result.statistics = null;
+		result.hasSourceHistory = false + "";
+		result.sourceHistory = null;
 		return result;
 	}
 
@@ -32,6 +36,8 @@ public static RenderedDetailedUserDefinedAction fromHotkey(String id, String nam
 		result.activation = RenderedTaskActivation.fromActivation(activationConstructor);
 		result.hasStatistics = false + "";
 		result.statistics = null;
+		result.hasSourceHistory = false + "";
+		result.sourceHistory = null;
 		return result;
 	}
 
@@ -43,6 +49,8 @@ public static RenderedDetailedUserDefinedAction fromUserDefinedAction(UserDefine
 		result.activation = RenderedTaskActivation.fromActivation(activationConstructor);
 		result.hasStatistics = true + "";
 		result.statistics = RenderedUserDefinedActionStatistics.fromUserDefinedActionStatistics(action.getStatistics());
+		result.hasSourceHistory = true + "";
+		result.sourceHistory = RenderedTaskSourceHistory.of(action.getActionId(), action.getTaskSourceHistory());
 		return result;
 	}
 
@@ -76,6 +84,12 @@ public RenderedUserDefinedActionStatistics getStatistics() {
 	public void setStatistics(RenderedUserDefinedActionStatistics statistics) {
 		this.statistics = statistics;
 	}
+	public String getHasSourceHistory() {
+		return hasSourceHistory;
+	}
+	public RenderedTaskSourceHistory getSourceHistory() {
+		return sourceHistory;
+	}
 	public String getIsEnabled() {
 		return isEnabled;
 	}
diff --git a/src/core/webui/server/handlers/renderedobjects/RenderedTaskSourceHistory.java b/src/core/webui/server/handlers/renderedobjects/RenderedTaskSourceHistory.java
new file mode 100644
index 00000000..c91b32c7
--- /dev/null
+++ b/src/core/webui/server/handlers/renderedobjects/RenderedTaskSourceHistory.java
@@ -0,0 +1,21 @@
+package core.webui.server.handlers.renderedobjects;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+import core.userDefinedTask.internals.TaskSourceHistory;
+
+public class RenderedTaskSourceHistory {
+
+	private List<RenderedTaskSourceHistoryEntry> entries;
+
+	public static RenderedTaskSourceHistory of(String taskId, TaskSourceHistory history) {
+		RenderedTaskSourceHistory result = new RenderedTaskSourceHistory();
+		result.entries = history.getEntries().stream().map(e -> RenderedTaskSourceHistoryEntry.of(taskId, e)).collect(Collectors.toList());
+		return result;
+	}
+
+	public List<RenderedTaskSourceHistoryEntry> getEntries() {
+		return entries;
+	}
+}
diff --git a/src/core/webui/server/handlers/renderedobjects/RenderedTaskSourceHistoryEntry.java b/src/core/webui/server/handlers/renderedobjects/RenderedTaskSourceHistoryEntry.java
new file mode 100644
index 00000000..1a77209f
--- /dev/null
+++ b/src/core/webui/server/handlers/renderedobjects/RenderedTaskSourceHistoryEntry.java
@@ -0,0 +1,28 @@
+package core.webui.server.handlers.renderedobjects;
+
+import core.userDefinedTask.internals.TaskSourceHistoryEntry;
+import utilities.DateUtility;
+
+public class RenderedTaskSourceHistoryEntry {
+	private String taskId;
+	private String createdTime;
+	private String createdTimeMillis;
+
+	public static RenderedTaskSourceHistoryEntry of(String taskId, TaskSourceHistoryEntry entry) {
+		RenderedTaskSourceHistoryEntry result = new RenderedTaskSourceHistoryEntry();
+		result.taskId = taskId;
+		result.createdTime = DateUtility.calendarToTimeString(entry.getCreated());
+		result.createdTimeMillis = entry.getCreated().getTimeInMillis() + "";
+		return result;
+	}
+
+	public String getTaskId() {
+		return taskId;
+	}
+	public String getCreatedTime() {
+		return createdTime;
+	}
+	public String getCreatedTimeMillis() {
+		return createdTimeMillis;
+	}
+}
diff --git a/src/frontEnd/MainBackEndHolder.java b/src/frontEnd/MainBackEndHolder.java
index 47b6823e..021e33cc 100644
--- a/src/frontEnd/MainBackEndHolder.java
+++ b/src/frontEnd/MainBackEndHolder.java
@@ -52,6 +52,7 @@
 import core.userDefinedTask.internals.RemoteRepeatsClientTools;
 import core.userDefinedTask.internals.RunActionConfig;
 import core.userDefinedTask.internals.SharedVariablesPubSubManager;
+import core.userDefinedTask.internals.TaskSourceHistoryEntry;
 import globalListener.GlobalListenerHookController;
 import staticResources.BootStrapResources;
 import utilities.Desktop;
@@ -857,6 +858,16 @@ public void switchEnableTask(UserDefinedAction action) {
 		}
 	}
 
+	public String getSourceForTask(UserDefinedAction action, long timestamp) {
+		TaskSourceHistoryEntry entry = action.getTaskSourceHistory().findEntry(timestamp);
+		if (entry == null) {
+			LOGGER.warning("No source path for action " + action.getName() + " at time " + timestamp + ".");
+			return null;
+		}
+
+		return FileUtility.readFromFile(entry.getSourcePath()).toString();
+	}
+
 	/**
 	 * Populate all tasks with task invoker to dynamically execute other tasks.
 	 */
diff --git a/src/staticContent/webui/templates/fragments/task_source_history.ftlh b/src/staticContent/webui/templates/fragments/task_source_history.ftlh
new file mode 100644
index 00000000..97073fbb
--- /dev/null
+++ b/src/staticContent/webui/templates/fragments/task_source_history.ftlh
@@ -0,0 +1,16 @@
+<#macro fragment>
+<#if task.hasSourceHistory == "true">
+    <h1> Source history </h1>
+    <table>
+        <tbody>
+            <#list task.sourceHistory.entries as entry>
+                <tr>
+                    <td><a href="/internals/get/task-source?id=${entry.taskId}&timestamp=${entry.createdTimeMillis}"> ${entry.createdTime} </a></td>
+                </tr>
+            </#list>
+        </tbody>
+    </table>
+</#if>
+</#macro>
+
+<@fragment/>
\ No newline at end of file
diff --git a/src/staticContent/webui/templates/task_details.ftlh b/src/staticContent/webui/templates/task_details.ftlh
index 4fde1ab5..fc0ddf49 100644
--- a/src/staticContent/webui/templates/task_details.ftlh
+++ b/src/staticContent/webui/templates/task_details.ftlh
@@ -1,5 +1,6 @@
 <#import "/fragments/activations_modals.ftlh" as activations_modals_fragment>
 <#import "/fragments/activations.ftlh" as activations_fragment>
+<#import "/fragments/task_source_history.ftlh" as task_source_history_fragment>
 <#import "/fragments/task_statistics.ftlh" as task_statistics_fragment>
 <#import "/fragments/common_header.ftlh" as common_header_fragment>
 <#import "/fragments/footer.ftlh" as footer_fragment>
@@ -56,6 +57,7 @@
                 <div id="task-activation-constructor-id" style="display:none;">${taskActivationConstructorId}</div>
 
                 <@activations_fragment.fragment/>
+                <@task_source_history_fragment.fragment/>
                 <@task_statistics_fragment.fragment/>
             </div>
         </div>