merge(abstraction): abstract extension to components (#21)

- Add new preview command abstraction (not yet implemented)
- Abstract single file extension.ts to class-based components to separate growing concerns
- Add git extension type to git.d.ts from [VSCode API repo](https://github.com/microsoft/vscode/blob/main/extensions/git/src/api/git.d.ts)
- Refactor all new files:
  - Replace wildcard import with specific named imports
  - Add explicit type imports for ExtensionContext and TextDocument etc
  - Improve error message formatting with newlines for better readability
  - Remove redundant string concatenation in error logging
- Update all tests to accomodate the updated formatting of errors

Author: tsdevau

src/apiKeyManager.ts

@@ -0,0 +1,65 @@
+import { type ExtensionContext, window } from "vscode"
+
+export class APIKeyManager {
+  constructor(private context: ExtensionContext) {}
+
+  async setAPIKey(): Promise<string | undefined> {
+    try {
+      const apiKey = await window.showInputBox({
+        prompt: "Enter your Anthropic API Key",
+        password: true,
+        placeHolder: "sk-ant-api...",
+      })
+
+      if (!apiKey) {
+        window.showErrorMessage("API Key is required")
+        return undefined
+      }
+
+      if (!apiKey.startsWith("sk-ant-api")) {
+        window.showErrorMessage("Invalid Anthropic API Key format. Should start with sk-ant-api")
+        return undefined
+      }
+
+      await this.context.secrets.store("anthropic-api-key", apiKey)
+      window.showInformationMessage("API Key updated successfully")
+
+      return apiKey
+    } catch (error) {
+      console.error("Secrets storage error:", error)
+      window.showErrorMessage(
+        `Failed to update API key in secure storage: ${error instanceof Error ? error.message : String(error)}`,
+      )
+      return undefined
+    }
+  }
+
+  async getAPIKey(): Promise<string | undefined> {
+    try {
+      return await this.context.secrets.get("anthropic-api-key")
+    } catch (error) {
+      console.error("Secrets storage error:", error)
+      window.showErrorMessage(
+        `Failed to access secure storage: ${error instanceof Error ? error.message : String(error)}`,
+      )
+      return undefined
+    }
+  }
+
+  async deleteAPIKey(): Promise<void> {
+    try {
+      const apiKey = await this.context.secrets.get("anthropic-api-key")
+      if (!apiKey) {
+        window.showWarningMessage("No API Key found to remove")
+        return
+      }
+      await this.context.secrets.delete("anthropic-api-key")
+      window.showInformationMessage("API Key deleted successfully")
+    } catch (error) {
+      console.error("Secrets storage error:", error)
+      window.showErrorMessage(
+        `Failed to delete API key from secure storage: ${error instanceof Error ? error.message : String(error)}`,
+      )
+    }
+  }
+}

src/cmdPreview.ts

@@ -0,0 +1,82 @@
+import * as vscode from "vscode"
+
+export function activate(context: vscode.ExtensionContext) {
+  // Keep track of document content in memory
+  const documentContent = new Map<string, string>()
+  const originalContent = new Map<string, string>()
+
+  // Create event emitter for content changes
+  const onDidChangeEmitter = new vscode.EventEmitter<vscode.Uri>()
+
+  // Register the content provider
+  const provider = {
+    onDidChange: onDidChangeEmitter.event,
+    provideTextDocumentContent: (uri: vscode.Uri) => documentContent.get(uri.path) || "",
+  }
+
+  const registration = vscode.workspace.registerTextDocumentContentProvider("commit-preview", provider)
+
+  const disposable = vscode.commands.registerCommand(
+    "extension.previewCommitMessage",
+    async (aiGeneratedMessage: string) => {
+      // Create URI for this preview
+      const uri = vscode.Uri.parse("commit-preview:Commit Message Preview")
+
+      // Store initial content
+      documentContent.set(uri.path, aiGeneratedMessage)
+      originalContent.set(uri.path, aiGeneratedMessage)
+
+      // Open the document
+      const doc = await vscode.workspace.openTextDocument(uri)
+      await vscode.window.showTextDocument(doc, {
+        preview: true,
+        preserveFocus: false,
+      })
+
+      // Handle saves
+      const saveListener = vscode.workspace.onDidSaveTextDocument((savedDoc) => {
+        if (savedDoc === doc) {
+          const content = documentContent.get(uri.path)
+          if (content) {
+            vscode.scm.inputBox.value = content
+            vscode.window.setStatusBarMessage("Commit message updated", 2000)
+          }
+        }
+      })
+
+      // Handle document changes
+      const changeListener = vscode.workspace.onDidChangeTextDocument((e) => {
+        if (e.document === doc) {
+          documentContent.set(uri.path, e.document.getText())
+          onDidChangeEmitter.fire(uri)
+        }
+      })
+
+      // Handle closing
+      const closeListener = vscode.workspace.onDidCloseTextDocument((closedDoc) => {
+        if (closedDoc === doc) {
+          const current = documentContent.get(uri.path)
+          const original = originalContent.get(uri.path)
+
+          // Only update SCM if content was modified
+          if (current && original && current !== original) {
+            vscode.scm.inputBox.value = current
+          }
+
+          // Cleanup
+          documentContent.delete(uri.path)
+          originalContent.delete(uri.path)
+          saveListener.dispose()
+          changeListener.dispose()
+          closeListener.dispose()
+        }
+      })
+
+      context.subscriptions.push(saveListener, changeListener, closeListener)
+    },
+  )
+
+  context.subscriptions.push(disposable, registration)
+}
+
+export function deactivate() {}

src/commitMessageGenerator.ts

@@ -0,0 +1,104 @@
+import Anthropic from "@anthropic-ai/sdk"
+import { window } from "vscode"
+import type { CommitConfig } from "./configManager"
+
+export class CommitMessageGenerator {
+  constructor(private apiKey: string) {}
+
+  async generateMessage(diff: string, config: CommitConfig): Promise<string | undefined> {
+    const anthropic = new Anthropic({
+      apiKey: this.apiKey,
+    })
+
+    const systemPrompt =
+      "You are a seasoned software developer with an extraordinary ability for writing detailed conventional commit messages and following 'instructions' and 'customInstructions' when generating them."
+
+    const prompt = `
+      <task>
+      Generate a detailed conventional commit message for the following Git diff:
+
+      ${diff}
+      </task>
+      <instructions>
+      - Use ONLY ${config.allowedTypes.map((val) => `'${val}'`).join(" | ")} as appropriate for the type of change.
+      - Always include a scope.
+      - Never use '!' or 'BREAKING CHANGE' in the commit message.
+      - Output will use markdown formatting for lists etc.
+      - Output will ONLY contain the commit message.
+      - Do not explain the output.
+      </instructions>
+      ${config.customInstructions ? `<customInstructions>\n${config.customInstructions}\n</customInstructions>` : ""}
+      `.trim()
+
+    let message: Anthropic.Message | undefined = undefined
+    try {
+      message = await anthropic.messages.create({
+        model: config.model,
+        max_tokens: config.maxTokens,
+        temperature: config.temperature,
+        system: systemPrompt,
+        messages: [
+          {
+            role: "user",
+            content: prompt,
+          },
+        ],
+      })
+
+      let commitMessage = message.content
+        .filter((msg) => msg.type === "text" && "text" in msg)
+        .map((msg) => msg.text)
+        .join("\n")
+        .replace(/\n{3,}/g, "\n\n") // Replace 3 or more newlines with 2 newlines
+        .replace(/(?<![\\\w])\*+[ \t]+/g, "- ") // Replace bullets occasionally output by the model with hyphens
+        .trim()
+
+      if (!commitMessage) {
+        window.showWarningMessage("No commit message was generated")
+        return undefined
+      }
+
+      // Replace bullets occasionally output by the model with hyphens
+      return commitMessage
+    } catch (error) {
+      this.handleError(error)
+      return undefined
+    } finally {
+      console.log("[DiffCommit] Stop Reason: ", message?.stop_reason)
+      console.log("[DiffCommit] Usage: ", message?.usage)
+    }
+  }
+
+  private handleError(error: unknown): void {
+    if (error instanceof Anthropic.APIError) {
+      const errorMessage = error.message || "Unknown Anthropic API error"
+      console.error(`Anthropic API Error (${error.status}):\n\n${errorMessage}`)
+
+      switch (error.status) {
+        case 400:
+          window.showErrorMessage("Bad request. Review your prompt and try again.")
+          break
+        case 401:
+          window.showErrorMessage("Invalid API key. Please update your API key and try again.")
+          break
+        case 403:
+          window.showErrorMessage("Permission Denied. Review your prompt or API key and try again.")
+          break
+        case 429:
+          window.showErrorMessage(`Rate limit exceeded. Please try again later:\n\n${errorMessage}`)
+          break
+        case 500:
+          window.showErrorMessage("Anthropic API server error. Please try again later.")
+          break
+        default:
+          window.showErrorMessage(`Failed to generate commit message:\n\n${errorMessage}`)
+          break
+      }
+    } else {
+      console.error(`Unknown error: ${error instanceof Error ? error.message : String(error)}`)
+      window.showErrorMessage(
+        `Unknown error generating commit message: ${error instanceof Error ? error.message : String(error)}`,
+      )
+    }
+  }
+}

src/configManager.ts

@@ -0,0 +1,38 @@
+import { workspace } from "vscode"
+
+export interface CommitConfig {
+  allowedTypes: string[]
+  customInstructions?: string
+  maxTokens: number
+  model: string
+  temperature: number
+}
+
+export class ConfigManager {
+  private static readonly defaultAllowedTypes = [
+    "feat",
+    "fix",
+    "refactor",
+    "chore",
+    "docs",
+    "style",
+    "test",
+    "perf",
+    "ci",
+  ]
+  private static readonly defaultMaxTokens = 1024
+  private static readonly defaultModel = "claude-3-5-sonnet-latest"
+  private static readonly defaultTemperature = 0.4
+
+  getConfig(): CommitConfig {
+    const config = workspace.getConfiguration("diffCommit")
+
+    return {
+      allowedTypes: config.get<string[]>("allowedTypes") || ConfigManager.defaultAllowedTypes,
+      customInstructions: config.get<string>("customInstructions"),
+      maxTokens: config.get<number>("maxTokens") || ConfigManager.defaultMaxTokens,
+      model: config.get<string>("model") || ConfigManager.defaultModel,
+      temperature: config.get<number>("temperature") || ConfigManager.defaultTemperature,
+    }
+  }
+}