#!/bin/bash

set -uexo pipefail

HOST_DMD_VER=2.072.2 # same as in dmd/src/posix.mak
CURL_USER_AGENT="CirleCI $(curl --version | head -n 1)"
N=2
CIRCLE_NODE_INDEX=${CIRCLE_NODE_INDEX:-0}
CIRCLE_PROJECT_REPONAME=${CIRCLE_PROJECT_REPONAME:-dmd}

case $CIRCLE_NODE_INDEX in
    0) MODEL=64 ;;
    1) MODEL=32 ;;
esac

# clone druntime and phobos
clone() {
    local url="$1"
    local path="$2"
    local branch="$3"
    for i in {0..4}; do
        if git clone --branch "$branch" "$url" "$path" "${@:4}"; then
            break
        elif [ $i -lt 4 ]; then
            sleep $((1 << $i))
        else
            echo "Failed to clone: ${url}"
            exit 1
        fi
    done
}

download() {
    local url="$1"
    local fallbackurl="$2"
    local outputfile="$3"
    for i in {0..4}; do
        if curl -fsS -A "$CURL_USER_AGENT" --max-time 5 "$url" -o "$outputfile" ||
           curl -fsS -A "$CURL_USER_AGENT" --max-time 5 "$fallbackurl" -o "$outputfile" ; then
            break
        elif [ $i -ge 4 ]; then
            sleep $((1 << $i))
        else
            echo "Failed to download script ${outputfile}" 1>&2
            exit 1
        fi
    done
}

install_deps() {
    if [ $MODEL -eq 32 ]; then
        sudo apt-get update --quiet=2
        sudo aptitude install g++-multilib --assume-yes --quiet=2
    fi

    download "https://dlang.org/install.sh" "https://nightlies.dlang.org/install.sh" "install.sh"

    source "$(CURL_USER_AGENT=\"$CURL_USER_AGENT\" bash install.sh dmd-$HOST_DMD_VER --activate)"
    $DC --version
    env
}

setup_repos() {
    # set a default in case we run into rate limit restrictions
    local base_branch=""
    if [ -n "${CIRCLE_PR_NUMBER:-}" ]; then
        base_branch=$((curl -fsSL https://api.github.com/repos/dlang/$CIRCLE_PROJECT_REPONAME/pulls/$CIRCLE_PR_NUMBER || echo) | jq -r '.base.ref')
    else
        base_branch=$CIRCLE_BRANCH
    fi
    base_branch=${base_branch:-"master"}

    # merge testee PR with base branch (master) before testing
    if [ -n "${CIRCLE_PR_NUMBER:-}" ]; then
        local head=$(git rev-parse HEAD)
        git fetch https://github.com/dlang/$CIRCLE_PROJECT_REPONAME.git $base_branch
        git checkout -f FETCH_HEAD
        local base=$(git rev-parse HEAD)
        git config user.name 'CI'
        git config user.email '<>'
        git merge -m "Merge $head into $base" $head
    fi

    for proj in druntime phobos; do
        if [ $base_branch != master ] && [ $base_branch != stable ] &&
            ! git ls-remote --exit-code --heads https://github.com/dlang/$proj.git $base_branch > /dev/null; then
            # use master as fallback for other repos to test feature branches
            clone https://github.com/dlang/$proj.git ../$proj master --depth 1
        else
            clone https://github.com/dlang/$proj.git ../$proj $base_branch --depth 1
        fi
    done
}

coverage()
{
    # load environment for bootstrap compiler
    source "$(CURL_USER_AGENT=\"$CURL_USER_AGENT\" bash ~/dlang/install.sh dmd-$HOST_DMD_VER --activate)"

    # build dmd, druntime, and phobos
    make -j$N -C src -f posix.mak MODEL=$MODEL HOST_DMD=$DMD all
    make -j$N -C ../druntime -f posix.mak MODEL=$MODEL
    make -j$N -C ../phobos -f posix.mak MODEL=$MODEL

    # rebuild dmd with coverage enabled
    # use the just build dmd as host compiler this time
    local build_path=generated/linux/release/$MODEL
    # `generated` gets cleaned in the next step, so we create another _generated
    # The nested folder hierarchy is needed to conform to those specified in
    # the generate dmd.conf
    mkdir -p _${build_path}
    cp $build_path/dmd _${build_path}/host_dmd
    cp $build_path/dmd.conf _${build_path}
    make -j$N -C src -f posix.mak MODEL=$MODEL HOST_DMD=../_${build_path}/host_dmd clean
    make -j$N -C src -f posix.mak MODEL=$MODEL HOST_DMD=../_${build_path}/host_dmd ENABLE_COVERAGE=1

    make -j$N -C test MODEL=$MODEL ARGS="-O -inline -release" DMD_TEST_COVERAGE=1
}

codecov()
{
    # CodeCov gets confused by lst files which it can't matched
    rm -rf test/runnable/extra-files
    download "https://codecov.io/bash" "https://raw.githubusercontent.com/codecov/codecov-bash/master/codecov" "codecov.sh"
    bash codecov.sh
}

case $1 in
    install-deps) install_deps ;;
    setup-repos) setup_repos ;;
    coverage) coverage ;;
    codecov) codecov ;;
esac