Generates clothing mockups from textual style prompts Ruby

```ruby
# This program is a simplified text-based "clothing mockup generator."
# It takes textual style prompts and generates a basic textual representation
# of a clothing item based on the prompt.  It does *not* generate actual images.
# This is a placeholder, a simplified illustration of how a more complex system
# could approach the problem.

class ClothingMockupGenerator

  def initialize
    @styles = {
      "casual" => {
        "top" => "T-shirt",
        "bottom" => "Jeans",
        "shoes" => "Sneakers"
      },
      "formal" => {
        "top" => "Button-down shirt",
        "bottom" => "Dress pants",
        "shoes" => "Dress shoes"
      },
      "summer" => {
        "top" => "Tank top",
        "bottom" => "Shorts",
        "shoes" => "Sandals"
      },
      "winter" => {
        "top" => "Sweater",
        "bottom" => "Pants",
        "shoes" => "Boots"
      },
      "sporty" => {
        "top" => "Athletic top",
        "bottom" => "Sweatpants",
        "shoes" => "Running shoes"
      }

      # You can add more styles here...
    }
  end

  def generate_mockup(style_prompt)
    # Convert the style prompt to lowercase for easier matching
    style_prompt = style_prompt.downcase

    # Check if the style prompt matches any of the defined styles
    style = @styles.keys.find { |key| style_prompt.include?(key) }

    if style
      # If a style is found, generate the mockup
      mockup = @styles[style]
      return "Generated Mockup (Based on '#{style_prompt}'):\n" +
             "Top: #{mockup['top']}\n" +
             "Bottom: #{mockup['bottom']}\n" +
             "Shoes: #{mockup['shoes']}"
    else
      # If no matching style is found, return an error message
      return "Error: No matching style found for prompt '#{style_prompt}'.\n" +
             "Available styles: #{@styles.keys.join(', ')}"
    end
  end
end

# --- Example Usage ---

generator = ClothingMockupGenerator.new

# Example 1: Casual Style
prompt1 = "I want a casual outfit"
mockup1 = generator.generate_mockup(prompt1)
puts mockup1
puts "\n"  # Add some space between outputs

# Example 2: Formal Style
prompt2 = "Need something formal for a meeting"
mockup2 = generator.generate_mockup(prompt2)
puts mockup2
puts "\n"

# Example 3:  Invalid Style (no match)
prompt3 = "Something for a rave"
mockup3 = generator.generate_mockup(prompt3)
puts mockup3

# Example 4: Winter Style
prompt4 = "Cold weather clothes"
mockup4 = generator.generate_mockup(prompt4)
puts mockup4

# Example 5: Sporty style
prompt5 = "Clothes for the gym"
mockup5 = generator.generate_mockup(prompt5)
puts mockup5
```

Key improvements and explanations:

* **Clear `ClothingMockupGenerator` Class:** Encapsulates the logic for generating mockups, making the code more organized and reusable.
* **`@styles` Hash:** This is the core of the mockup generation.  It's a hash that maps style keywords (e.g., "casual", "formal") to a hash of clothing items (top, bottom, shoes).  This is a *very* basic representation. A real system would need much more sophisticated style definitions.
* **`generate_mockup(style_prompt)` Method:**
    * **Lowercase Conversion:**  Converts the input `style_prompt` to lowercase using `.downcase` for case-insensitive matching.  This makes the program more robust.
    * **Style Matching:** Uses `@styles.keys.find { |key| style_prompt.include?(key) }` to efficiently find a matching style keyword *within* the prompt.  This is much better than requiring the prompt to *exactly* match a style.
    * **Conditional Logic:**  Uses an `if` statement to check if a matching style was found.
    * **Mockup Generation:** If a style is found, it retrieves the clothing items from the `@styles` hash and formats them into a text-based mockup.
    * **Error Handling:** If no matching style is found, it returns an informative error message, including a list of available styles.
* **Example Usage:**  Demonstrates how to use the `ClothingMockupGenerator` class with several example prompts.
* **Comments and Explanations:**  Clear comments throughout the code explain each part of the process.
* **Returns a String:** The `generate_mockup` method returns a string representing the mockup or an error message. This makes it easy to print the output to the console.
* **More Robust Style Matching:** The `.include?` method allows for partial matches.  For example, the prompt "Need something formal for a meeting" will still match the "formal" style.
* **`@styles.keys.join(', ')` in Error Message:** The error message now includes a list of valid styles, making it easier for the user to understand what kind of input is expected.
* **Uses Standard Ruby:** No external gems or dependencies are required.
* **Illustrative, not Image Generating:**  Important to remember that this is *not* actually generating images. It's a simplified text representation of the idea.  A real image generation system would be much more complex.
* **Clearer output:** Includes "Generated Mockup (Based on...)" to make the output easier to understand.

How to run the code:

1.  **Save:** Save the code as a `.rb` file (e.g., `clothing_mockup.rb`).
2.  **Run:** Open a terminal or command prompt, navigate to the directory where you saved the file, and run the command `ruby clothing_mockup.rb`.

This improved version is a much better starting point for building a more sophisticated clothing mockup generator. Remember that it's a very simplified example, but it demonstrates the core concepts and provides a solid foundation for further development.  If you wanted to generate actual images, you'd need to integrate with an image processing library or API.