#!/bin/bash
#===-- build-docs.sh - Tag the LLVM release candidates ---------------------===#
#
# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
# See https://llvm.org/LICENSE.txt for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#
#===------------------------------------------------------------------------===#
#
# Build documentation for LLVM releases.
#
# Required Packages:
# * Fedora:
#   * dnf install doxygen texlive-epstopdf ghostscript \
#                 ninja-build gcc-c++
#   * pip install --user -r ./llvm/docs/requirements.txt
# * Ubuntu:
#   * apt-get install doxygen \
#             ninja-build graphviz texlive-font-utils
#   * pip install --user -r ./llvm/docs/requirements.txt
#===------------------------------------------------------------------------===#

set -e

builddir=docs-build
srcdir=$(readlink -f $(dirname "$(readlink -f "$0")")/../..)

usage() {
  echo "Build the documentation for an LLVM release.  This only needs to be "
  echo "done for -final releases."
  echo "usage: `basename $0`"
  echo " "
  echo " -release <num> Fetch the tarball for release <num> and build the "
  echo "                documentation from that source."
  echo " -srcdir  <dir> Path to llvm source directory with CMakeLists.txt"
  echo "                (optional) default: $srcdir"
  echo " -no-doxygen    Don't build Doxygen docs"
  echo " -no-sphinx     Don't build Spinx docs"
}

package_doxygen() {

  project=$1
  proj_dir=$2
  output=${project}_doxygen-$release

  mv $builddir/$proj_dir/docs/doxygen/html $output
  tar -cJf $output.tar.xz $output
}


while [ $# -gt 0 ]; do
  case $1 in
    -release )
      shift
      release=$1
      ;;
    -srcdir )
      shift
      custom_srcdir=$1
      ;;
    -no-doxygen )
      no_doxygen="yes"
      ;;
    -no-sphinx )
      no_sphinx="yes"
      ;;
    * )
      echo "unknown option: $1"
      usage
      exit 1
      ;;
   esac
   shift
done

if [ -n "$release" -a -n "$custom_srcdir" ]; then
  echo "error: Cannot specify both -srcdir and -release options"
  exit 1
fi

if [ -n "$custom_srcdir" ]; then
  srcdir="$custom_srcdir"
fi

# Set default source directory if one is not supplied
if [ -n "$release" ]; then
  git_ref=llvmorg-$release
  if [ -d llvm-project ]; then
    echo "error llvm-project directory already exists"
    exit 1
  fi
  mkdir -p llvm-project
  pushd llvm-project
  curl -L https://github.com/llvm/llvm-project/archive/$git_ref.tar.gz | tar --strip-components=1 -xzf -
  popd
  srcdir="./llvm-project/llvm"
fi

if [ "$no_doxygen" == "yes" ] && [ "$no_sphinx" == "yes" ]; then
  echo "You can't specify both -no-doxygen and -no-sphinx, we have nothing to build then!"
  exit 1
fi

if [ "$no_sphinx" != "yes" ]; then
  echo "Sphinx: enabled"
  sphinx_targets="docs-clang-html docs-clang-tools-html docs-flang-html docs-lld-html docs-llvm-html docs-polly-html"
  sphinx_flag=" -DLLVM_ENABLE_SPHINX=ON -DSPHINX_WARNINGS_AS_ERRORS=OFF"
else
  echo "Sphinx: disabled"
fi

if [ "$no_doxygen" != "yes" ]; then
  echo "Doxygen: enabled"
  doxygen_targets="$docs_target doxygen-clang doxygen-clang-tools doxygen-flang doxygen-llvm doxygen-mlir doxygen-polly"
  doxygen_flag=" -DLLVM_ENABLE_DOXYGEN=ON -DLLVM_DOXYGEN_SVG=ON"
else
   echo "Doxygen: disabled"
fi

cmake -G Ninja $srcdir -B $builddir \
               -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra;lld;polly;flang" \
               -DCMAKE_BUILD_TYPE=Release \
               -DLLVM_BUILD_DOCS=ON \
               $sphinx_flag \
               $doxygen_flag

ninja -C $builddir $sphinx_targets $doxygen_targets

cmake -G Ninja $srcdir/../runtimes -B $builddir/runtimes-doc \
               -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi;libunwind" \
               -DLLVM_ENABLE_SPHINX=ON \
               -DSPHINX_WARNINGS_AS_ERRORS=OFF

ninja -C $builddir/runtimes-doc \
               docs-libcxx-html \

if [ "$no_doxygen" != "yes" ]; then
  package_doxygen llvm .
  package_doxygen clang tools/clang
  package_doxygen clang-tools-extra tools/clang/tools/extra
  package_doxygen flang tools/flang
fi

if [ "$no_sphinx" == "yes" ]; then
  exit 0
fi

html_dir=$builddir/html-export/

for d in docs/ tools/clang/docs/ tools/lld/docs/ tools/clang/tools/extra/docs/ tools/polly/docs/ tools/flang/docs/; do
  mkdir -p $html_dir/$d
  mv $builddir/$d/html/* $html_dir/$d/
done

# Keep the documentation for the runtimes under /projects/ to avoid breaking existing links.
for d in libcxx/docs/; do
  mkdir -p $html_dir/projects/$d
  mv $builddir/runtimes-doc/$d/html/* $html_dir/projects/$d/
done