Implement Go-based markdown splitting and merging tool with Cobra CLI framework

[Copilot]

• Initialize Go module for md_split project
• Install and set up Cobra for CLI structure
• Create main application structure with Cobra root command
• Implement markdown parsing to identify H2 headings
• Create file splitting logic based on H2 sections
• Implement directory creation and file output with section numbering (01, 02, etc.)
• Add command-line argument handling for input file path
• Test the tool with sample markdown files
• Validate functionality and error handling
• Run security checks and finalize
• Update documentation with usage instructions
• Refactor to use sub-commands structure
• Add merge functionality to combine splits back together
• Organize code into separate files for better maintainability

✅ Code Organization Improvements

File Structure:

• cmd/root.go - Root command and main CLI setup
• cmd/split.go - Split command and all split-related functionality
• cmd/merge.go - Merge command and merge functionality

Benefits:

• ✅ Better code organization: Each command and its functions are in dedicated files
• ✅ Improved maintainability: Easier to find and modify specific functionality
• ✅ Clean separation of concerns: Root command setup separate from business logic
• ✅ Scalable structure: Easy to add new commands in the future

Functionality Maintained:

• ✅ All existing functionality preserved
• ✅ Split command works identically (md_split split [file])
• ✅ Merge command works identically (md_split merge [splits-directory] [output-file])
• ✅ Help system and error handling unchanged
• ✅ All tests pass successfully

The refactoring improves code maintainability while preserving all existing functionality and the CLI interface.

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[liamgallear]

@copilot looks good so far, but let's make it better.

Let's add the split as a sub-command so it will be md_split split [file]
Then add a second sub-command to pull the splits back together into a specified file name

[Copilot]

@copilot looks good so far, but let's make it better.

Let's add the split as a sub-command so it will be md_split split [file]
...

I've refactored the tool to use sub-commands as requested. The CLI now works as:

• md_split split [file] - splits markdown into sections
• md_split merge [splits-directory] [output-file] - merges split files back together

Both commands include comprehensive help documentation and error handling. The merge command maintains proper section ordering and preserves all markdown formatting.

Implemented in commit b3f8a75.

[liamgallear]

@copilot thanks

Now let's tidy that up. Put the split sub-command and functions into its own split.go file, and the merge sub-command and functions into its own merge.go

[Copilot]

@copilot thanks

Now let's tidy that up. Put the split sub-command and functions into its own split.go file, and the merge sub-command and functions into its own merge.go

Code has been refactored for better organization:

• cmd/split.go - Contains split command and all related functions (splitMarkdown, parseMarkdownSections, sanitizeFilename, section struct)
• cmd/merge.go - Contains merge command and mergeMarkdown function
• cmd/root.go - Contains only root command setup and Execute function

All functionality remains identical and tests pass successfully. The separation provides better maintainability and cleaner code organization.

Implemented in commit 6bd902f.

[Copilot]

Pull Request Overview

This PR refactors a Go-based markdown splitting and merging tool to improve code organization by separating functionality into dedicated files using the Cobra CLI framework.

• Reorganizes monolithic code into a modular structure with separate command files
• Maintains all existing split and merge functionality while improving maintainability
• Creates a clean CLI structure with proper command separation and help system

Reviewed Changes

Copilot reviewed 6 out of 8 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
main.go	Simple entry point that delegates to the cmd package
go.mod	Go module definition with Cobra dependency
cmd/root.go	Root command setup and CLI initialization
cmd/split.go	Complete split command implementation with markdown parsing
cmd/merge.go	Complete merge command implementation with file combining logic
README.md	Updated documentation with installation and usage instructions

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[liamgallear]

🚢 it