pandoc-format

#!/usr/bin/env bash
#
# Wrapper script for pandoc to format markdown files
# Used as a pre-commit hook

set -euo pipefail

# Check if pandoc is installed
if ! command -v pandoc &> /dev/null; then
    echo "Error: pandoc is not installed. Please install pandoc before using this hook."
    echo "Visit https://pandoc.org/installing.html for installation instructions."
    exit 1
fi

# Default values
COLUMNS=80
USE_REFERENCE_LINKS=true
FROM_FORMAT="gfm"
TO_FORMAT="gfm"

# Parse arguments
FILES=()
while [[ $# -gt 0 ]]; do
    case "$1" in
        --columns)
            if [[ $# -lt 2 ]]; then
                echo "Error: --columns requires an argument"
                exit 1
            fi
            COLUMNS="$2"
            shift 2
            ;;
        --no-reference-links)
            USE_REFERENCE_LINKS=false
            shift
            ;;
        --from)
            if [[ $# -lt 2 ]]; then
                echo "Error: --from requires an argument"
                exit 1
            fi
            FROM_FORMAT="$2"
            shift 2
            ;;
        --to)
            if [[ $# -lt 2 ]]; then
                echo "Error: --to requires an argument"
                exit 1
            fi
            TO_FORMAT="$2"
            shift 2
            ;;
        *)
            FILES+=("$1")
            shift
            ;;
    esac
done

# Check if any files were provided
if [ ${#FILES[@]} -eq 0 ]; then
    echo "Error: No files provided"
    exit 1
fi

# Build pandoc arguments
PANDOC_ARGS=(
    "--columns=$COLUMNS"
    "-s"
    "-f" "$FROM_FORMAT"
    "-t" "$TO_FORMAT"
)

if [ "$USE_REFERENCE_LINKS" = true ]; then
    PANDOC_ARGS+=("--reference-links")
fi

# Process each file
exit_code=0

for file in "${FILES[@]}"; do
    # Create a temporary file for output
    tmpfile=$(mktemp)
    
    # Run pandoc with the specified flags
    if pandoc "${PANDOC_ARGS[@]}" --output "$tmpfile" "$file" 2>/dev/null; then
        
        # Check if the file changed
        if ! cmp -s "$file" "$tmpfile"; then
            # Replace the original file with the formatted version
            mv "$tmpfile" "$file"
            echo "Formatted: $file"
            exit_code=1
        else
            rm "$tmpfile"
        fi
    else
        echo "Error: Failed to format $file"
        rm -f "$tmpfile"
        exit_code=1
    fi
done

exit $exit_code