feat(config): add Config class for centralized configuration management

- Introduce Config class to handle tool configuration
- Add support for output directory, exclusions, diff format, and dark mode
- Refactor CLI and SDK to use new Config class
- Update documentation with new configuration options

Author: bayuagpr-xaltius

README.md

@@ -8,7 +8,7 @@ A powerful CLI tool that generates beautifully formatted markdown files from git
 
 ## Why?
 
-So GitHub/GitLab/Bitbucket diff views works for you? Good. But sometimes those might be not your remote git provider and/or your diff view from your remote git providers might be not so friendly moreover if you have to review big changes (at least for your eyes). This tool simply offers an alternative that lets you:
+So GitHub/GitLab/Bitbucket diff views works for you? Well good for you! But sometimes those remote git providers might be not your remote git provider and/or your diff view from your remote git providers might be not so friendly moreover if you have to review big changes (at least for your eyes). This tool simply offers an alternative that lets you:
 
 - Generate clean, readable diffs when your remote git provider diff views are unavailable or unfriendly
 - Work completely offline - only needs internet access when comparing remote branches
@@ -32,7 +32,10 @@ So GitHub/GitLab/Bitbucket diff views works for you? Good. But sometimes those m
 - 🎨 Syntax-highlighted diff output
 - 📊 Includes file statistics and change summaries
 - 🔍 Automatic exclusion of common build artifacts and sensitive files
-- 📁 Preserves your repository's directory structure and generates a searchable diff index for easy navigation
+- 📁 Output directory structure mirrors your repository layout with a searchable index file containing:
+  - Total change statistics
+  - Commit messages between compared refs
+  - Links to individual file diffs with change summaries
 - 💡 Support for comparing specific commits, branches, or tags
 - 🚀 Progress indicators for long-running operations
 
@@ -62,21 +65,114 @@ git-markdown-diff
 To generate diffs between specific git references (commits, branches, or tags):
 
 ```bash
-git-markdown-diff <startRef> <endRef>
+git-markdown-diff --start-ref <startRef> --end-ref <endRef>
 ```
 
 Examples:
 ```bash
 # Compare between two commits
-git-markdown-diff abc123 def456
+git-markdown-diff -s abc123 -e def456
 
 # Compare between branches
-git-markdown-diff main feature/new-feature
+git-markdown-diff --start-ref main --end-ref feature/new-feature
 
 # Compare between tags
-git-markdown-diff v1.0.0 v1.1.0
+git-markdown-diff -s v1.0.0 -e v1.1.0
 ```
 
+### Configuration Options
+
+```bash
+Options:
+  -s, --start-ref <ref>      Starting reference (commit hash, branch name, or tag)
+  -e, --end-ref <ref>        Ending reference (commit hash, branch name, or tag)
+  -o, --output <dir>         Output directory (default: "git-diffs")
+  --exclude <patterns>       Additional file patterns to exclude
+  -f, --format <format>      Diff format: diff, unified, side-by-side (default: "diff")
+  --light-mode              Use light mode theme instead of dark mode
+  -h, --help                Display help
+
+# Examples:
+git-markdown-diff -s main -e develop -o custom-diffs    # Custom output directory
+git-markdown-diff --exclude "*.log" "*.tmp"             # Exclude additional files
+git-markdown-diff -s HEAD -e HEAD~1 -f side-by-side     # Side-by-side diff format
+git-markdown-diff -s v1.0 -e v2.0 --light-mode         # Light mode theme
+```
+
+### Programmatic Usage
+
+```javascript
+const GitMarkdownDiff = require('git-markdown-diff');
+
+const differ = new GitMarkdownDiff({
+  outputDir: 'custom-dir',
+  exclusions: ['*.log', '*.tmp'],
+  diffFormat: 'side-by-side',
+  darkMode: false
+});
+
+await differ.run('main', 'feature/branch');
+```
+
+#### Use it in your code:
+```javascript
+// Generate diffs for code review tools
+const GitMarkdownDiff = require('git-markdown-diff');
+
+async function generateReviewDiff(prNumber) {
+  const differ = new GitMarkdownDiff({
+    outputDir: `pr-${prNumber}-diff`,
+    diffFormat: 'side-by-side'
+  });
+  
+  await differ.run('main', `pr-${prNumber}`);
+  return `pr-${prNumber}-diff/README.md`;
+}
+```
+
+#### Git hooks integration:
+```javascript
+// pre-commit hook (/.git/hooks/pre-commit)
+const GitMarkdownDiff = require('git-markdown-diff');
+
+async function preCommitHook() {
+  const differ = new GitMarkdownDiff({
+    outputDir: '.git/diff-preview',
+    diffFormat: 'unified'
+  });
+  
+  // Compare staged changes
+  await differ.run('HEAD', '--staged');
+  // Open diff preview in default browser
+  require('open')('.git/diff-preview/README.md');
+}
+```
+
+#### CI/CD pipeline:
+```javascript
+// GitHub Actions, Jenkins, etc.
+const GitMarkdownDiff = require('git-markdown-diff');
+
+async function generatePRDiff() {
+  const differ = new GitMarkdownDiff({
+    outputDir: 'ci-diff-output',
+    exclusions: ['*.lock', 'dist/*']
+  });
+  
+  // Compare PR branch with target branch
+  await differ.run(process.env.TARGET_BRANCH, process.env.PR_BRANCH);
+  
+  // Upload diff as artifact or send to review system
+  await uploadArtifact('ci-diff-output');
+}
+```
+
+### Diff Formats
+
+- `diff` (default) - Standard git diff format
+- `unified` - Unified diff with 3 lines of context
+- `side-by-side` - Two-column comparison view
+
 ## Output Structure
 
 The tool creates a `git-diffs` directory with the following structure:

package.json

@@ -1,6 +1,6 @@
 {
   "name": "git-markdown-diff",
-  "version": "0.0.39",
+  "version": "0.0.40",
   "description": "Git diff tool that outputs markdown formatted diffs",
   "main": "src/sdk/GitMarkdownDiff.js",
   "bin": {
@@ -20,6 +20,13 @@
   ],
   "author": "Bayu Prakoso",
   "license": "MIT",
+  "files": [
+    "src/sdk/**/*",
+    "src/cli/**/*"
+  ],
+  "exports": {
+    ".": "./src/sdk/GitMarkdownDiff.js"
+  },
   "dependencies": {
     "commander": "^11.0.0",
     "ora": "^8.1.1"

src/cli/index.js

@@ -3,18 +3,25 @@
 const { program } = require("commander");
 const GitMarkdownDiff = require("../sdk/GitMarkdownDiff");
 
-// CLI setup
 program
   .name("git-markdown-diff")
   .description("Generate markdown-formatted git diffs")
-  .argument(
-    "[startRef]",
-    "Starting reference (commit hash, branch name, or tag)"
-  )
-  .argument("[endRef]", "Ending reference (commit hash, branch name, or tag)")
-  .action(async (startRef, endRef) => {
-    const differ = new GitMarkdownDiff();
-    await differ.run(startRef, endRef);
+  .option("-s, --start-ref <ref>", "Starting reference (commit hash, branch name, or tag)")
+  .option("-e, --end-ref <ref>", "Ending reference (commit hash, branch name, or tag)")
+  .option("-o, --output <dir>", "Output directory", "git-diffs")
+  .option("--exclude <patterns...>", "Additional file patterns to exclude")
+  .option("-f, --format <format>", "Diff format (diff, unified, side-by-side)", "diff")
+  .option("--light-mode", "Use light mode theme instead of dark mode")
+  .action(async (options) => {
+    const config = {
+      outputDir: options.output,
+      exclusions: options.exclude || [],
+      diffFormat: options.format,
+      darkMode: !options.lightMode
+    };
+    
+    const differ = new GitMarkdownDiff(config);
+    await differ.run(options.startRef, options.endRef);
   });
 
-program.parse(); 
+program.parse();

src/sdk/GitMarkdownDiff.js

@@ -1,10 +1,10 @@
 const gitUtils = require('./utils/gitUtils');
 const fsUtils = require('./utils/fsUtils');
-const EXCLUSIONS = require('./constants/gitExclusions');
+const Config = require('./config/Config');
 
 class GitMarkdownDiff {
-  constructor(outputDir = "git-diffs") {
-    this.outputDir = outputDir;
+  constructor(options = {}) {
+    this.config = new Config(options);
   }
 
   async run(startRange, endRange) {
@@ -13,21 +13,21 @@ class GitMarkdownDiff {
 
     try {
       await gitUtils.validateGit();
-      fsUtils.cleanupOutputDir(this.outputDir);
+      fsUtils.cleanupOutputDir(this.config.outputDir);
 
       const range = this.#buildGitRange(startRange, endRange);
 
       spinner.text = "Getting list of changed files...";
-      const changedFiles = await gitUtils.getChangedFiles(range, EXCLUSIONS);
+      const changedFiles = await gitUtils.getChangedFiles(range, this.config.getExclusions());
       const totalStats = await gitUtils.getTotalStats(range);
 
       const index = await this.#buildIndexContent(startRange, endRange, totalStats, range);
       await this.#processFiles(changedFiles, range, spinner, index);
 
       spinner.text = "Writing index file...";
-      fsUtils.writeIndexFile(this.outputDir, index.join("\n"));
+      fsUtils.writeIndexFile(this.config.outputDir, index.join("\n"));
 
-      spinner.succeed(`Diffs saved to ${this.outputDir}/`);
+      spinner.succeed(`Diffs saved to ${this.config.outputDir}/`);
     } catch (error) {
       spinner.fail("Failed to generate diffs");
       console.error(error);
@@ -43,7 +43,7 @@ class GitMarkdownDiff {
       const fileInfo = await gitUtils.getFileInfo(file, range);
       const content = await this.#generateFileContent(file, range, fileInfo);
 
-      fsUtils.saveFile(this.outputDir, file, content);
+      fsUtils.saveFile(this.config.outputDir, file, content);
       this.#updateIndex(index, file, fileInfo);
     }
   }
@@ -71,10 +71,10 @@ class GitMarkdownDiff {
   }
 
   async #generateFileContent(file, range, fileInfo) {
-    const diffOutput = await gitUtils.getFileDiff(file, range);
+    const diffOutput = await gitUtils.getFileDiff(file, range, this.config.diffFormat);
 
     return [
-      this.#getCssStyle(),
+      this.config.getCssStyle(),
       `generated at ${new Date().toLocaleString()} (${Intl.DateTimeFormat().resolvedOptions().timeZone})`,
       "",
       `# Changes in \`${file}\``,
@@ -93,24 +93,6 @@ class GitMarkdownDiff {
     ].join("\n");
   }
 
-  #getCssStyle() {
-    return `<!--
-<style>
-.markdown-body .highlight pre, .markdown-body pre {
-  background-color: #0d1117;
-}
-.markdown-body .diff-deletion {
-  color: #f85149;
-  background-color: #3c1618;
-}
-.markdown-body .diff-addition {
-  color: #56d364;
-  background-color: #1b4721;
-}
-</style>
--->`;
-  }
-
   #updateIndex(index, file, fileInfo) {
     const stats = fileInfo.match(/(\d+) insertion.+(\d+) deletion/)?.[0] || "No changes";
     index.push(`- [${file}](./${file}.md) - ${stats}`);

src/sdk/config/Config.js

@@ -0,0 +1,35 @@
+class Config {
+  constructor(options = {}) {
+    this.outputDir = options.outputDir || "git-diffs";
+    this.exclusions = options.exclusions || [];
+    this.diffFormat = options.diffFormat || "diff"; // possible values: diff, unified, side-by-side
+    this.darkMode = options.darkMode ?? true;
+  }
+
+  getExclusions() {
+    const defaultExclusions = require('../constants/gitExclusions');
+    return [...defaultExclusions, ...this.exclusions];
+  }
+
+  getCssStyle() {
+    if (!this.darkMode) return '';
+    
+    return `<!--
+<style>
+.markdown-body .highlight pre, .markdown-body pre {
+  background-color: #0d1117;
+}
+.markdown-body .diff-deletion {
+  color: #f85149;
+  background-color: #3c1618;
+}
+.markdown-body .diff-addition {
+  color: #56d364;
+  background-color: #1b4721;
+}
+</style>
+-->`;
+  }
+}
+
+module.exports = Config; 

src/sdk/utils/gitUtils.js

@@ -34,9 +34,17 @@ const gitUtils = {
     return stdout;
   },
 
-  async getFileDiff(file, range) {
-    const { stdout } = await execAsync(`git diff ${range} -- "${file}"`, {
-      maxBuffer: 10 * 1024 * 1024,
+  async getFileDiff(file, range, format = 'diff') {
+    const formatFlags = {
+      'diff': '',
+      'unified': ' -U3',
+      'side-by-side': ' --side-by-side --width=180'
+    };
+
+    const flag = formatFlags[format] || '';
+    const cmd = `git diff${flag} ${range} -- "${file}"`;
+    const { stdout } = await execAsync(cmd, {
+      maxBuffer: 10 * 1024 * 1024
     });
     return stdout;
   },