Convert markdown to rich text format for Slack/Discord/etc

md2pb

#!/usr/bin/env bash

# md2pb - Convert markdown to rich text format for Slack/Discord/etc
#
# DESCRIPTION:
#   Converts markdown to both plain text and HTML formats, then places both on the
#   macOS clipboard. This allows pasting rich formatted text into apps like Slack,
#   Discord, or any app that accepts HTML clipboard data.
#
# USAGE:
#   md2pb [FILE]
#   echo "**bold text**" | md2pb
#   md2pb README.md
#
# REQUIREMENTS:
#   - macOS (uses osascript and pbcopy)
#   - pandoc (brew install pandoc)
#
# EXAMPLES:
#   # From stdin
#   echo "# Header\n**Bold** and *italic* text" | md2pb
#
#   # From file
#   md2pb my-notes.md
#
#   # With llm tool
#   llm logs -n 1 -r | md2pb
#
# AUTHOR: Stuart Corbishley
# DATE: 2025-06-26

set -euo pipefail

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

# Function to print colored output
print_error() {
  echo -e "${RED}❌ Error: $1${NC}" >&2
}

print_success() {
  echo -e "${GREEN}✅ $1${NC}"
}

print_warning() {
  echo -e "${YELLOW}⚠️  Warning: $1${NC}"
}

print_info() {
  echo -e "$1"
}

# Check if we're on macOS
check_macos() {
  if [[ "$OSTYPE" != "darwin"* ]]; then
    print_error "This script requires macOS (uses osascript and pbcopy)"
    print_info "Current OS: $OSTYPE"
    exit 1
  fi
}

# Check if pandoc is installed
check_pandoc() {
  if ! command -v pandoc &>/dev/null; then
    print_error "pandoc is required but not installed"
    print_info ""
    print_info "Install with:"
    print_info "  brew install pandoc"
    print_info ""
    print_info "Or visit: https://pandoc.org/installing.html"
    exit 1
  fi
}

# Show usage
show_usage() {
  echo "Usage: md2pb [OPTIONS] [FILE]"
  echo ""
  echo "Convert markdown to rich text format for clipboard"
  echo ""
  echo "Options:"
  echo "  --debug-html=FILE    Save HTML output to FILE for debugging"
  echo "  --debug-text=FILE    Save plain text output to FILE for debugging"
  echo "  --style=STYLE        Formatting style: slack (default) or normal"
  echo "  -h, --help          Show this help message"
  echo ""
  echo "Arguments:"
  echo "  FILE    Markdown file to convert (optional, uses stdin if not provided)"
  echo ""
  echo "Examples:"
  echo "  echo \"**bold text**\" | md2pb"
  echo "  md2pb README.md"
  echo "  md2pb --style=normal README.md"
  echo "  md2pb --debug-html=output.html --debug-text=output.txt README.md"
  echo "  llm logs -n 1 -r | md2pb"
}

# Main conversion function
convert_markdown_to_clipboard() {
  local input_source="$1"
  local debug_html_file="$2"
  local debug_text_file="$3"
  local style="$4"

  local tmpdir=""
  local tmphtml=""
  local tmptext=""
  local tmpfilter=""

  # Cleanup function
  cleanup() {
    rm -rf "${tmpdir:-}"
  }
  trap cleanup EXIT

  # Create temporary directory and files
  tmpdir=$(mktemp -d /tmp/markdown-clipboard.XXXXXX)
  tmphtml="$tmpdir/output.html"
  tmptext="$tmpdir/output.txt"
  tmpfilter="$tmpdir/filter.lua"

  # Create lua filter for Slack formatting
  cat >"$tmpfilter" <<'EOF'
function Header(elem)
  -- Convert headers to bold text for Slack/Discord
  local content = pandoc.utils.stringify(elem.content)
  return {
    pandoc.Para{pandoc.LineBreak()},
    pandoc.Para{pandoc.Strong{pandoc.Str(content)}}
  }
end

function Para(elem)
  return {
    pandoc.Para{pandoc.LineBreak()},
    elem
  }
end
EOF

  # Configure markdown format based on style
  local markdown_extensions=(
    "markdown"
    "+lists_without_preceding_blankline"
    "+strikeout"
    "+autolink_bare_uris"
    "+task_lists"
    "-smart"
  )
  local markdown_format
  markdown_format=$(
    IFS=""
    echo "${markdown_extensions[*]}"
  )

  local pandoc_html_args=()

  if [[ "$style" == "slack" ]]; then
    pandoc_html_args+=("--lua-filter=$tmpfilter")
  fi

  pandoc_html_args+=("-t" "html" "--standalone")

  # Convert to both formats
  if [[ "$input_source" == "stdin" ]]; then
    # Read from stdin
    local content
    content=$(cat)

    if [[ -z "$content" ]]; then
      print_error "No input provided"
      exit 1
    fi

    echo "$content" | pandoc -f "$markdown_format" -t plain >"$tmptext"
    echo "$content" | pandoc -f "$markdown_format" "${pandoc_html_args[@]}" >"$tmphtml"
  else
    # Read from file
    if [[ ! -f "$input_source" ]]; then
      print_error "File not found: $input_source"
      exit 1
    fi

    if [[ ! -r "$input_source" ]]; then
      print_error "Cannot read file: $input_source"
      exit 1
    fi

    pandoc -f "$markdown_format" -t plain "$input_source" >"$tmptext"
    pandoc -f "$markdown_format" "${pandoc_html_args[@]}" "$input_source" >"$tmphtml"
  fi

  # Set plain text version first (this is the key!)
  if ! pbcopy <"$tmptext"; then
    print_error "Failed to copy plain text to clipboard"
    exit 1
  fi

  # Add HTML format to existing clipboard
  if ! osascript \
    -e "set htmlData to (read POSIX file \"$tmphtml\" as «class HTML»)" \
    -e 'set currentClip to the clipboard as record' \
    -e 'set the clipboard to (currentClip & {«class HTML»:htmlData})' \
    2>/dev/null; then
    print_error "Failed to add HTML format to clipboard"
    exit 1
  fi

  # Save HTML to debug file if requested
  if [[ -n "$debug_html_file" ]]; then
    if cp "$tmphtml" "$debug_html_file"; then
      print_info "🐛 HTML debug output saved to: $debug_html_file"
    else
      print_warning "Failed to save HTML debug output to: $debug_html_file"
    fi
  fi

  # Save plain text to debug file if requested
  if [[ -n "$debug_text_file" ]]; then
    if cp "$tmptext" "$debug_text_file"; then
      print_info "🐛 Plain text debug output saved to: $debug_text_file"
    else
      print_warning "Failed to save plain text debug output to: $debug_text_file"
    fi
  fi

  # Show success message with preview
  local line_count word_count
  line_count=$(wc -l <"$tmptext" | tr -d ' ')
  word_count=$(wc -w <"$tmptext" | tr -d ' ')

  print_success "Markdown converted and copied to clipboard"
  print_info "📊 Stats: $line_count lines, $word_count words"
  print_info "📋 Ready to paste into Slack, Discord, or other rich text apps"
}

# Main script logic
main() {
  local debug_html_file=""
  local debug_text_file=""
  local input_file=""
  local style="slack"

  # Parse command line arguments
  while [[ $# -gt 0 ]]; do
    case $1 in
    -h | --help | help)
      show_usage
      exit 0
      ;;
    --debug-html=*)
      debug_html_file="${1#*=}"
      if [[ -z "$debug_html_file" ]]; then
        print_error "--debug-html requires a filename"
        exit 1
      fi
      shift
      ;;
    --debug-text=*)
      debug_text_file="${1#*=}"
      if [[ -z "$debug_text_file" ]]; then
        print_error "--debug-text requires a filename"
        exit 1
      fi
      shift
      ;;
    --style=*)
      style="${1#*=}"
      if [[ "$style" != "slack" && "$style" != "normal" ]]; then
        print_error "Style must be 'slack' or 'normal', got: $style"
        exit 1
      fi
      shift
      ;;
    -*)
      print_error "Unknown option: $1"
      echo ""
      show_usage
      exit 1
      ;;
    *)
      if [[ -n "$input_file" ]]; then
        print_error "Too many input files specified"
        echo ""
        show_usage
        exit 1
      fi
      input_file="$1"
      shift
      ;;
    esac
  done

  # Check system requirements
  check_macos
  check_pandoc

  # Determine input source
  if [[ -z "$input_file" ]]; then
    # No input file, check if stdin has data
    if [[ -t 0 ]]; then
      print_error "No input provided"
      echo ""
      show_usage
      exit 1
    fi
    convert_markdown_to_clipboard "stdin" "$debug_html_file" "$debug_text_file" "$style"
  else
    # Input file specified
    convert_markdown_to_clipboard "$input_file" "$debug_html_file" "$debug_text_file" "$style"
  fi
}

# Run main function with all arguments
main "$@"