Colored Calendar 🦀

A fast, modern Rust implementation of an enhanced calendar tool that improves upon the standard Unix cal command with colored weekends, weekday-only display options, and flexible month viewing.

Features

• Colored Weekends: Displays Saturday and Sunday in grey for better visual distinction
• Weekdays-Only Mode: Shows only Monday through Friday when using the -w flag
• Today's Date Highlighting: Highlights today's date with inverted colors (when displaying current year)
• Year Selection: Display any year (defaults to current year)
• Month Display Mode: Show specific months with the -m flag instead of full year view
• Smart Year Display: Hides current year, shows future years as 2-digit format (e.g., "26" for 2026)
• Fast Performance: Built with Rust for blazing-fast execution
• Clean Output: Maintains the familiar cal command layout with visual enhancements

Installation

From Source (Recommended)

1. Prerequisites: Install Rust if you haven't already
2. Clone and build:

   git clone <repository-url>
   cd ccal
   cargo build --release
   

3. Install globally (optional):

   cargo install --path .
   

Quick Run (Without Installation)

cargo run -- [OPTIONS] [YEAR]

Usage

ccal [OPTIONS] [YEAR]

Options

• -w, --weekdays: Show only weekdays (Monday-Friday)
• -m, --months [BEFORE] [AFTER]: Display months only (hides year). See examples below for usage patterns.
• -h, --help: Print help information
• -V, --version: Print version information
• YEAR: Year to display (defaults to current year, ignored when using -m)

Month Display Mode (-m flag)

The -m flag provides flexible month viewing with intelligent year display:

• Current year months: Year is hidden (e.g., "August", "September")
• Future year months: Year shown as 2-digit format (e.g., "January 26", "February 26")
• Combines with -w: Works seamlessly with weekdays-only mode

-m Usage Patterns:

• -m (no arguments): Show current month only
• -m X (one number): Show current month + X months after
• -m X Y (two numbers): Show X months before + current month + Y months after

Examples

Year View (Default)

# Display current year with colored weekends
ccal

# Display 2024 with colored weekends  
ccal 2024

# Display current year with weekdays only
ccal -w

# Display 2025 with weekdays only
ccal -w 2025

Month View (-m flag)

# Show current month only
ccal -m

# Show current month + next month
ccal -m 1

# Show current month + next 2 months
ccal -m 2

# Show previous month + current + next month
ccal -m 1 1

# Show 2 months before + current + 1 month after
ccal -m 2 1

# Month view with weekdays only
ccal -m 3 -w

# Show current month through next 5 months (spans years)
ccal -m 5

Development Usage

# Using cargo run during development
cargo run -- -w 2024
cargo run -- -m 2 1

Requirements

• Rust: 1.70+ (2021 edition)
• Dependencies:
  • clap - Command line argument parsing
  • chrono - Date and time handling
  • colored - Terminal color output

Color Scheme

• Weekdays: Default terminal color
• Weekends (Saturday/Sunday): Grey
• Today's Date: Inverted colors (black text on white background)

How It Works

The Rust implementation provides three display modes:

1. Full Year Mode (default): Shows complete year calendar with weekend days colored in grey
2. Weekdays-Only Mode (-w flag): Displays only Monday through Friday, removing weekend columns entirely
3. Month Display Mode (-m flag): Shows specific months without year header, with smart year labeling:
   • Current year months: No year shown
   • Future/past years: 2-digit year format (e.g., "26" for 2026)

The calendar uses the chrono crate for accurate date calculations and colored for terminal styling, ensuring consistent behavior across different systems. Month calculations properly handle year transitions.

Development

Building

# Debug build
cargo build

# Release build (optimized)
cargo build --release

# Run tests
cargo test

# Run with arguments
cargo run -- --help

Project Structure

src/
├── main.rs        # CLI interface and argument parsing
└── calendar.rs    # Core calendar logic and display

Performance

This Rust implementation is significantly faster than shell script alternatives, with:

• ⚡ Instant startup time
• 🔧 Zero external command dependencies
• 🎯 Memory-efficient date calculations
• 🌐 Cross-platform compatibility

Contributing

Feel free to submit issues or pull requests to improve the calendar tool!

License

This project is open source and available under the MIT OR Apache-2.0 license.