#!/bin/bash
# Diagram rendering script - supports TikZ, Typst/CeTZ, and SVG

set -e

USAGE="Usage: $0 <input_file> [output.png]

Supported formats:
  .tex    - TikZ/LaTeX diagrams (requires pdflatex + imagemagick/poppler)
  .typ    - Typst/CeTZ diagrams (requires typst)
  .svg    - SVG diagrams (requires inkscape or imagemagick)

Examples:
  $0 diagram.tex                  # Creates diagram.png
  $0 diagram.typ output.png       # Creates output.png
"

if [ $# -lt 1 ]; then
    echo "$USAGE"
    exit 1
fi

INPUT="$1"
EXT="${INPUT##*.}"
BASENAME="${INPUT%.*}"

# Determine output file
if [ $# -ge 2 ]; then
    OUTPUT="$2"
else
    OUTPUT="${BASENAME}.png"
fi

echo "Rendering: $INPUT -> $OUTPUT"

case "$EXT" in
    tex)
        # TikZ/LaTeX workflow
        if ! command -v pdflatex &> /dev/null; then
            echo "Error: pdflatex not found. Install with:"
            echo "  sudo apt-get install texlive texlive-pictures"
            exit 1
        fi

        # Compile to PDF
        pdflatex -interaction=nonstopmode -output-directory="$(dirname "$INPUT")" "$INPUT" > /dev/null
        PDF="${BASENAME}.pdf"

        # Convert PDF to PNG
        if command -v pdftoppm &> /dev/null; then
            # Use poppler (cleaner, better quality)
            pdftoppm "$PDF" "${BASENAME}" -png -singlefile -r 300
            mv "${BASENAME}.png" "$OUTPUT"
        elif command -v convert &> /dev/null; then
            # Use ImageMagick
            convert -density 300 "$PDF" -quality 90 "$OUTPUT"
        else
            echo "Error: Need pdftoppm (poppler-utils) or convert (imagemagick)"
            echo "Install with: sudo apt-get install poppler-utils"
            exit 1
        fi

        # Cleanup LaTeX aux files
        rm -f "${BASENAME}.aux" "${BASENAME}.log" "${BASENAME}.pdf"
        echo "Created: $OUTPUT"
        ;;

    typ)
        # Typst workflow
        if ! command -v typst &> /dev/null; then
            echo "Error: typst not found. Install with:"
            echo "  curl -fsSL https://typst.community/typst-install/install.sh | sh"
            echo "Or: cargo install --git https://github.com/typst/typst"
            exit 1
        fi

        # Compile to PNG directly
        typst compile "$INPUT" "$OUTPUT" --ppi 300
        echo "Created: $OUTPUT"
        ;;

    svg)
        # SVG workflow
        if command -v inkscape &> /dev/null; then
            inkscape "$INPUT" --export-type=png --export-filename="$OUTPUT" --export-dpi=300
        elif command -v convert &> /dev/null; then
            convert -density 300 -background white -alpha remove "$INPUT" "$OUTPUT"
        else
            echo "Error: Need inkscape or imagemagick"
            echo "Install with: sudo apt-get install inkscape"
            exit 1
        fi
        echo "Created: $OUTPUT"
        ;;

    *)
        echo "Error: Unsupported file extension: .$EXT"
        echo "$USAGE"
        exit 1
        ;;
esac