feat(ai): add streaming SSE support and new prompt templates

- Stream AI responses token-by-token via SSE for instant feedback - Add EXPLAIN, REVIEW, CHANGELOG, SUGGEST system prompts - Add buildExplainPrompt, buildReviewPrompt, buildChangelogPrompt, buildSuggestBranchPrompt, buildSuggestTypePrompt functions - Review prompt supports strict/lenient/normal modes
2026-06-16 02:00:56 +08:00
parent 8b21ab8d4a
commit c0c3dfce7d
2 changed files with 227 additions and 77 deletions
@@ -1,5 +1,7 @@
 import type { PRContext, ProjectContext } from "./types";

+// ── Commit System Prompt ──────────────────────────────────────────────
+
 export const SYSTEM_PROMPT = `You are an expert at writing concise, meaningful git commit messages following the Conventional Commits specification.

 Format: <type>(<scope>): <description>
@@ -19,29 +21,17 @@ Rules:
 export function buildPrompt(context: ProjectContext): string {
  const parts: string[] = [];

-  if (
-    context.packageDescription ||
-    context.readme ||
-    context.structure
-  ) {
+  if (context.packageDescription || context.readme || context.structure) {
    parts.push("## Project Context");
-    if (context.packageDescription) {
-      parts.push(`Description: ${context.packageDescription}`);
-    }
-    if (context.structure) {
-      parts.push(`Structure: ${context.structure}`);
-    }
-    if (context.readme) {
-      parts.push(`README:\n${context.readme}`);
-    }
+    if (context.packageDescription) parts.push(`Description: ${context.packageDescription}`);
+    if (context.structure) parts.push(`Structure: ${context.structure}`);
+    if (context.readme) parts.push(`README:\n${context.readme}`);
    parts.push("");
  }

  if (context.recentCommits.length > 0) {
    parts.push("## Recent Commits (for style reference)");
-    for (const c of context.recentCommits) {
-      parts.push(c);
-    }
+    for (const c of context.recentCommits) parts.push(c);
    parts.push("");
  }

@@ -55,6 +45,8 @@ export function buildPrompt(context: ProjectContext): string {
  return parts.join("\n");
 }

+// ── PR System Prompt ───────────────────────────────────────────────────
+
 export const PR_SYSTEM_PROMPT = `You are an expert at writing clear, concise pull request titles and descriptions.

 Format:
@@ -74,21 +66,11 @@ Rules:
 export function buildPRPrompt(context: PRContext): string {
  const parts: string[] = [];

-  if (
-    context.packageDescription ||
-    context.readme ||
-    context.structure
-  ) {
+  if (context.packageDescription || context.readme || context.structure) {
    parts.push("## Project Context");
-    if (context.packageDescription) {
-      parts.push(`Description: ${context.packageDescription}`);
-    }
-    if (context.structure) {
-      parts.push(`Structure: ${context.structure}`);
-    }
-    if (context.readme) {
-      parts.push(`README:\n${context.readme}`);
-    }
+    if (context.packageDescription) parts.push(`Description: ${context.packageDescription}`);
+    if (context.structure) parts.push(`Structure: ${context.structure}`);
+    if (context.readme) parts.push(`README:\n${context.readme}`);
    parts.push("");
  }

@@ -99,9 +81,7 @@ export function buildPRPrompt(context: PRContext): string {

  if (context.branchCommits.length > 0) {
    parts.push("## Commits on This Branch");
-    for (const c of context.branchCommits) {
-      parts.push(c);
-    }
+    for (const c of context.branchCommits) parts.push(c);
    parts.push("");
  }

@@ -110,9 +90,141 @@ export function buildPRPrompt(context: PRContext): string {
  parts.push(context.diff);
  parts.push("```");
  parts.push("");
-  parts.push(
-    "Generate a pull request title and brief body for the above changes.",
-  );
+  parts.push("Generate a pull request title and brief body for the above changes.");

  return parts.join("\n");
 }
+
+// ── Explain Prompt ─────────────────────────────────────────────────────
+
+export const EXPLAIN_SYSTEM_PROMPT = `You are an expert software engineer explaining code changes in plain, accessible language.
+
+Given a git diff, explain:
+1. WHAT changed at a high level (1 sentence summary)
+2. WHY these changes matter (what problem they solve or what they enable)
+3. A brief breakdown of the key changes (bullet points, one per file/module)
+
+Rules:
+- Be concise but thorough
+- Use plain language suitable for both junior and senior engineers
+- Focus on the intent and impact, not just restating the diff
+- Do NOT use markdown headings (no ##, ###). Use bold text markers like **Section:** instead.
+- Keep each bullet point to 1-2 lines
+- If the diff is trivial, say so and keep the explanation short`;
+
+export function buildExplainPrompt(diff: string): string {
+  const parts: string[] = [];
+  parts.push("## Changes to Explain");
+  parts.push("```diff");
+  parts.push(diff);
+  parts.push("```");
+  parts.push("");
+  parts.push("Explain these changes in plain language as described.");
+  return parts.join("\n");
+}
+
+// ── Review Prompt ──────────────────────────────────────────────────────
+
+export const REVIEW_SYSTEM_PROMPT = `You are a senior software engineer performing a thorough but friendly code review.
+
+Review the following code changes and provide feedback in these categories:
+1. **Bugs & Logic Errors** — actual bugs, off-by-one errors, null safety, edge cases
+2. **Code Quality** — readability, naming, duplication, complexity
+3. **Performance** — inefficient patterns, unnecessary allocations, N+1 queries
+4. **Security** — injection risks, exposed secrets, unsafe operations
+5. **Suggestions** — concrete improvements with code snippets where helpful
+
+Rules:
+- Be constructive, not harsh. Use "consider" and "suggest" instead of "you should".
+- Prioritize by severity. Mention critical issues first.
+- If the code looks great, say so! Don't fabricate issues.
+- Keep feedback actionable — every issue should have a clear suggestion.
+- Use **bold** for section headers and \`code\` for code references.
+- Do NOT output a concluding summary paragraph. End with the last suggestion.`;
+
+export function buildReviewPrompt(diff: string, strictness: "lenient" | "normal" | "strict"): string {
+  const strictnessHints: Record<string, string> = {
+    lenient: "Focus only on major issues. Skip minor style nits.",
+    normal: "Provide balanced feedback covering all categories.",
+    strict: "Be thorough. Flag even minor issues and style inconsistencies.",
+  };
+
+  const parts: string[] = [];
+  parts.push(`Review strictness: ${strictnessHints[strictness]}`);
+  parts.push("");
+  parts.push("## Code Changes to Review");
+  parts.push("```diff");
+  parts.push(diff);
+  parts.push("```");
+  parts.push("");
+  parts.push("Please review the above changes.");
+  return parts.join("\n");
+}
+
+// ── Changelog Prompt ───────────────────────────────────────────────────
+
+export const CHANGELOG_SYSTEM_PROMPT = `You are an expert at writing clear, user-facing changelogs from git commit history.
+
+Given a list of commits, generate a changelog organized by type:
+- **Features** (feat commits)
+- **Bug Fixes** (fix commits)
+- **Improvements** (refactor, perf, style commits)
+- **Documentation** (docs commits)
+- **Chores & Maintenance** (chore, build, ci, test commits)
+
+Rules:
+- Group by type, with the heading in **bold**
+- Each entry should be a single line describing the change in user-friendly language
+- Translate technical commit messages into language a user would understand
+- Skip merge commits and trivial chore commits if they don't add value
+- If a type has no entries, omit that section
+- Output ONLY the changelog text, no preamble or markdown code blocks`;
+
+export function buildChangelogPrompt(commits: string[], from?: string, to?: string): string {
+  const parts: string[] = [];
+  const range = from ? `from ${from}${to ? ` to ${to}` : " to HEAD"}` : "";
+  parts.push(range ? `Generate a changelog for commits ${range}.` : "Generate a changelog from the following commits.");
+  parts.push("");
+  parts.push("## Commits");
+  for (const c of commits) parts.push(c);
+  parts.push("");
+  parts.push("Generate a changelog from these commits.");
+  return parts.join("\n");
+}
+
+// ── Suggest Prompt ─────────────────────────────────────────────────────
+
+export const SUGGEST_SYSTEM_PROMPT = `You are an expert at suggesting git branch names and commit types based on code changes.
+
+For branch name suggestions:
+- Use format: <type>/<short-description>
+- Types: feat, fix, refactor, docs, chore, perf, test
+- Description should be 2-4 hyphenated words
+- Provide exactly 3 suggestions, one per line
+
+For commit type suggestions:
+- Return exactly one Conventional Commit type that best matches the changes
+- Valid types: feat, fix, docs, style, refactor, perf, test, build, ci, chore, revert
+- Output ONLY the type name`;
+
+export function buildSuggestBranchPrompt(diff: string): string {
+  const parts: string[] = [];
+  parts.push("## Changes");
+  parts.push("```diff");
+  parts.push(diff);
+  parts.push("```");
+  parts.push("");
+  parts.push("Suggest 3 branch names for these changes. Output one per line, no numbering.");
+  return parts.join("\n");
+}
+
+export function buildSuggestTypePrompt(diff: string): string {
+  const parts: string[] = [];
+  parts.push("## Changes");
+  parts.push("```diff");
+  parts.push(diff);
+  parts.push("```");
+  parts.push("");
+  parts.push("What Conventional Commit type best describes these changes? Output ONLY the type name.");
+  return parts.join("\n");
+}