1 files changed, 155 insertions, 0 deletions
diff --git a/packages/cli/src/ui/commands/restoreCommand.ts b/packages/cli/src/ui/commands/restoreCommand.ts
new file mode 100644
index 00000000..3d744189
--- /dev/null
+++ b/packages/cli/src/ui/commands/restoreCommand.ts
@@ -0,0 +1,155 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import * as fs from 'fs/promises';
+import path from 'path';
+import {
+  type CommandContext,
+  type SlashCommand,
+  type SlashCommandActionReturn,
+} from './types.js';
+import { Config } from '@google/gemini-cli-core';
+
+async function restoreAction(
+  context: CommandContext,
+  args: string,
+): Promise<void | SlashCommandActionReturn> {
+  const { services, ui } = context;
+  const { config, git: gitService } = services;
+  const { addItem, loadHistory } = ui;
+
+  const checkpointDir = config?.getProjectTempDir()
+    ? path.join(config.getProjectTempDir(), 'checkpoints')
+    : undefined;
+
+  if (!checkpointDir) {
+    return {
+      type: 'message',
+      messageType: 'error',
+      content: 'Could not determine the .gemini directory path.',
+    };
+  }
+
+  try {
+    // Ensure the directory exists before trying to read it.
+    await fs.mkdir(checkpointDir, { recursive: true });
+    const files = await fs.readdir(checkpointDir);
+    const jsonFiles = files.filter((file) => file.endsWith('.json'));
+
+    if (!args) {
+      if (jsonFiles.length === 0) {
+        return {
+          type: 'message',
+          messageType: 'info',
+          content: 'No restorable tool calls found.',
+        };
+      }
+      const truncatedFiles = jsonFiles.map((file) => {
+        const components = file.split('.');
+        if (components.length <= 1) {
+          return file;
+        }
+        components.pop();
+        return components.join('.');
+      });
+      const fileList = truncatedFiles.join('\n');
+      return {
+        type: 'message',
+        messageType: 'info',
+        content: `Available tool calls to restore:\n\n${fileList}`,
+      };
+    }
+
+    const selectedFile = args.endsWith('.json') ? args : `${args}.json`;
+
+    if (!jsonFiles.includes(selectedFile)) {
+      return {
+        type: 'message',
+        messageType: 'error',
+        content: `File not found: ${selectedFile}`,
+      };
+    }
+
+    const filePath = path.join(checkpointDir, selectedFile);
+    const data = await fs.readFile(filePath, 'utf-8');
+    const toolCallData = JSON.parse(data);
+
+    if (toolCallData.history) {
+      if (!loadHistory) {
+        // This should not happen
+        return {
+          type: 'message',
+          messageType: 'error',
+          content: 'loadHistory function is not available.',
+        };
+      }
+      loadHistory(toolCallData.history);
+    }
+
+    if (toolCallData.clientHistory) {
+      await config?.getGeminiClient()?.setHistory(toolCallData.clientHistory);
+    }
+
+    if (toolCallData.commitHash) {
+      await gitService?.restoreProjectFromSnapshot(toolCallData.commitHash);
+      addItem(
+        {
+          type: 'info',
+          text: 'Restored project to the state before the tool call.',
+        },
+        Date.now(),
+      );
+    }
+
+    return {
+      type: 'tool',
+      toolName: toolCallData.toolCall.name,
+      toolArgs: toolCallData.toolCall.args,
+    };
+  } catch (error) {
+    return {
+      type: 'message',
+      messageType: 'error',
+      content: `Could not read restorable tool calls. This is the error: ${error}`,
+    };
+  }
+}
+
+async function completion(
+  context: CommandContext,
+  _partialArg: string,
+): Promise<string[]> {
+  const { services } = context;
+  const { config } = services;
+  const checkpointDir = config?.getProjectTempDir()
+    ? path.join(config.getProjectTempDir(), 'checkpoints')
+    : undefined;
+  if (!checkpointDir) {
+    return [];
+  }
+  try {
+    const files = await fs.readdir(checkpointDir);
+    return files
+      .filter((file) => file.endsWith('.json'))
+      .map((file) => file.replace('.json', ''));
+  } catch (_err) {
+    return [];
+  }
+}
+
+export const restoreCommand = (config: Config | null): SlashCommand | null => {
+  if (!config?.getCheckpointingEnabled()) {
+    return null;
+  }
+
+  return {
+    name: 'restore',
+    description:
+      'Restore a tool call. This will reset the conversation and file history to the state it was in when the tool call was suggested',
+    action: restoreAction,
+    completion,
+  };
+};