AI-powered git commit message generator, for Fish shell

gcm-llm.fish

function gcm
    # Check if llm is installed, if not, install it
    if not type -q llm
        echo "'llm' is not installed. Attempting to install it using brew..."
        if brew install llm
            echo "'llm' installed successfully."
        else
            echo "Failed to install 'llm'. Please install it manually and try again."
            return 1
        end
    end

    # Check if an API key is set up for llm
    set llm_keys (llm keys)
    if test "$llm_keys" = "No keys found"
        echo "No API key found for 'llm'. You need to set it up."
        llm keys set openai
        if test $status -ne 0
            echo "Failed to set up the OpenAI key. Please try again manually."
            return 1
        else
            echo "OpenAI key set successfully."
        end
    end

    # Function to generate commit message
    function generate_commit_message
        set -l prompt_text "
Below is a diff of all changes, coming from the command:
\`\`\`
git diff -U1000 --cached
\`\`\`
Please generate a concise, one-line commit message that accurately summarises all the changes, following the
Conventional Commits style.
Follow this by an empty line, then a short, terse description in one sentences of the changes contained within
this commit, only covering detail not included in the summary. The description line should contain no capitals
or punctuation, and be as brief and blunt as possible.
Don't wrap your response in backticks or any other characters.

----------
"
        set -l diff_output

        if contains -- -a $argv
            set diff_output (git diff -U1000 HEAD)
        else
            set diff_output (git diff -U1000 --cached)
        end

        set prompt_text "$prompt_text$diff_output"

        echo $prompt_text | llm | string collect

    end

    # Function to read user input
    function read_input
        set -l prompt $argv[1]
        read -P $prompt reply
        echo $reply
    end

    # Main script
    echo "Generating AI-powered commit message..."
    set commit_message (generate_commit_message)

    while true
        echo -e "Proposed commit message:\n"
        echo -e "$commit_message"
        echo -e ""

        set choice (read_input "Do you want to (c)ancel, (a)ccept, (e)dit or (r)egenerate? ")

        switch $choice
            case 'a' 'A' ''
                if echo "$commit_message" | git commit $argv --file -
                    echo "Changes committed successfully!"
                    return 0
                else
                    echo "Commit failed. Please check your changes and try again."
                    return 1
                end
            case 'e' 'E'
                set commit_message (read -P "Enter your commit message: " -m)
                if [ -n "$commit_message" ]
                    if echo "$commit_message" | git commit $argv --file -
                        echo "Changes committed successfully with your message!"
                        return 0
                    else
                        echo "Commit failed. Please check your message and try again."
                        return 1
                    end
                else
                    echo "Empty commit message. Please try again."
                end
            case 'r' 'R'
                echo "Regenerating commit message..."
                set commit_message (generate_commit_message)
            case 'c' 'C' 'q' 'Q'
                echo "Commit cancelled."
                return 1
            case '*'
                echo "Invalid choice. Please try again."
        end
    end
end