#!/usr/bin/env bash

set -euo pipefail

# Prepare conda
CONDA_PATH=$(which conda)
eval "$(${CONDA_PATH} shell.bash hook)"

# Setup the OS_TYPE environment variable that should be used for conditions involving the OS below.
case $(uname) in
  Linux)
    OS_TYPE=linux
    ;;
  Darwin)
    OS_TYPE=macos
    ;;
  MSYS*)
    OS_TYPE=windows
    ;;
  *)
    echo "Unknown OS type:" $(uname)
    exit 1
    ;;
esac

if [[ "${OS_TYPE}" == "macos" && $(uname -m) == x86_64 ]]; then
  echo '::group::Uninstall system JPEG libraries on macOS'
  # The x86 macOS runners, e.g. the GitHub Actions native "macos-12" runner, has some JPEG libraries installed by
  # default that interfere with our build. We uninstall them here and use the one from conda below.
  JPEG_LIBS=$(brew list | grep jpeg)
  echo $JPEG_LIBS
  for lib in $JPEG_LIBS; do
    brew uninstall --ignore-dependencies --force $lib || true
  done
  echo '::endgroup::'
fi

echo '::group::Create build environment'
# See https://github.com/pytorch/vision/issues/7296 for ffmpeg
conda create \
  --name ci \
  --quiet --yes \
  python="${PYTHON_VERSION}" pip \
  ninja \
  libpng jpeg \
  'ffmpeg<4.3'
conda activate ci
pip install --progress-bar=off --upgrade setuptools

# See https://github.com/pytorch/vision/issues/6790
if [[ "${PYTHON_VERSION}" != "3.11" ]]; then
  pip install --progress-bar=off av!=10.0.0
fi

echo '::endgroup::'

echo '::group::Install PyTorch'
# TODO: Can we maybe have this as environment variable in the job template? For example, `IS_RELEASE`.
if [[ (${GITHUB_EVENT_NAME} = 'pull_request' && (${GITHUB_BASE_REF} = 'release'*)) || (${GITHUB_REF} = 'refs/heads/release'*) ]]; then
  CHANNEL=test
else
  CHANNEL=nightly
fi

pip install --progress-bar=off light-the-torch
ltt install --progress-bar=off \
  --pytorch-computation-backend="${GPU_ARCH_TYPE}${GPU_ARCH_VERSION}" \
  --pytorch-channel="${CHANNEL}" \
  torch

if [[ $GPU_ARCH_TYPE == 'cuda' ]]; then
  python -c "import torch; exit(not torch.cuda.is_available())"
fi
echo '::endgroup::'

if [[ "${OS_TYPE}" == "windows" ]]; then
  echo '::group::Install third party dependencies prior to TorchVision install on Windows'
  # `easy_install`, i.e. `python setup.py` has problems downloading the dependencies due to SSL.
  # Thus, we install them upfront with `pip` to avoid that.
  # Instead of fixing the SSL error, we can probably maintain this special case until we switch away from the deprecated
  # `easy_install` anyway.
  python setup.py egg_info
  # The requires.txt cannot be used with `pip install -r` directly. The requirements are listed at the top and the
  # optional dependencies come in non-standard syntax after a blank line. Thus, we just extract the header.
  sed -e '/^$/,$d' *.egg-info/requires.txt > requirements.txt
  pip install --progress-bar=off -r requirements.txt
  echo '::endgroup::'
fi

echo '::group::Install TorchVision'
python setup.py develop
echo '::endgroup::'

echo '::group::Collect PyTorch environment information'
python -m torch.utils.collect_env
echo '::endgroup::'
