#!/usr/bin/env bash

set -e -o pipefail
shopt -s extglob

VERSION=
NEXT_VERSION=
BRANCH=$(git rev-parse --abbrev-ref HEAD)
NARGS=0
DRY_RUN=
INSANE=0

# usage [ERROR-MESSAGES...] EXIT-CODE
usage() {
    while [[ $# -gt 1 ]]; do
        echo "$1" >&2
        shift
    done
    echo "Usage:"
    echo "./release.sh [OPTIONS] <VERSION_TO_RELEASE> [NEXT_VERSION]"
    echo ""
    echo "Options:"
    echo " --dry-run|-n: only print commands, do not execute them."
    echo ""
    echo "Examples:"
    echo " When releasing a new point release:"
    echo "   ./release.sh 0.6.3 0.6.4"
    echo " When releasing a new major version:"
    echo "   ./release.sh 0.7.0 0.8.0"
    echo ""
    echo "You may omit NEXT_VERSION in order to avoid updating the version field"
    echo "of the package.json."
    echo ""
    echo "Run this on the master branch, if you have permission to directly push"
    echo "to the master branch. Otherwise, create a branch with the version number"
    echo "as its name and a suffix to distinguish from its tag, e.g.,"
    echo "'v1.0.0-release', and run this on it."
    exit $1
}

while [ $# -gt 0 ]; do
    case "$1" in
        --dry-run|-n|--just-print)
            DRY_RUN=true
            git() { echo "git $*"; }
            yarn() { echo "yarn $*"; }
            ;;
        -h|-\?|--help)
            usage 0
            ;;
        -*)
            usage "Unknown option: $1" "" 1
            ;;
        *)
            case "$NARGS" in
                0)
                    VERSION="$1"
                    NARGS=1
                    ;;
                1)
                    NEXT_VERSION="$1"
                    NARGS=2
                    ;;
                *)
                    usage "Too many arguments: $1" "" 1
                    ;;
            esac
            ;;
    esac
    shift
done

if [[ $NARGS = 0 ]]; then
    usage "Missing argument: version number" "" 1
fi

# Some sanity checks up front
if ! command git diff --stat --exit-code HEAD; then
    echo "Please make sure you have no uncommitted changes" >&2
    : $((++INSANE))
fi
if [[ $BRANCH != @(v*|master) ]]; then
    echo "'$BRANCH' does not look like a release branch to me" >&2
    : $((++INSANE))
fi

if [[ -z "$NEXT_VERSION" ]]; then
    echo "About to release $VERSION from $BRANCH. "
else
    echo "About to release $VERSION from $BRANCH and bump to $NEXT_VERSION-pre."
fi
if [[ $INSANE != 0 ]]; then
    read -r -p "$INSANE sanity check(s) failed, really proceed? [y/n] " CONFIRM
else
    read -r -p "Look good? [y/n] " CONFIRM
fi
if [[ "$CONFIRM" != "y" ]]; then
    exit 1
fi

# Make a new detached HEAD
git checkout "$BRANCH"
git pull
git checkout --detach

# Edit package.json to the right version (see
# http://stackoverflow.com/a/22084103 for why we need the .bak file to make
# this mac & linux compatible)
sed -i.bak -E 's|"version": "[^"]+",|"version": "'$VERSION'",|' package.json
rm -f package.json.bak

# Build generated files and add them to the repository
git clean -fdx dist
yarn dist
sed -i.bak -E '/^\/dist\/$/d' .gitignore
rm -f .gitignore.bak
git add .gitignore dist/

# Edit docs to use CSS from CDN
grep -l '{@stylesheet: katex.min.css}' docs/*.md | xargs sed -i.bak \
    's|{@stylesheet: katex.min.css}|<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/katex@./dist/katex.min.css" integrity="sha384-katex.min.css" crossorigin="anonymous"/>|'

# Update the version number in CDN URLs included in the README and the documentation,
# and regenerate the Subresource Integrity hash for these files.
node update-sri.js "${VERSION}" README.md contrib/*/README.md dist/README.md \
    docs/*.md docs/*.md.bak website/pages/index.html

# Generate a new version of the docs and publish the website
pushd website
yarn run version "${VERSION}"

# Restore docs to use local built CSS
for file in ../docs/*.md.bak; do
    mv -f "$file" "${file%.bak}"
done

USE_SSH=true yarn publish-gh-pages
popd

# Make the commit and tag, and push them.
git add package.json README.md contrib/*/README.md dist/README.md \
    docs/*.md website/pages/index.html website/versioned_docs/ \
    website/versioned_sidebars/ website/versions.json
git commit -n -m "v$VERSION"
git diff --stat --exit-code # check for uncommitted changes
git tag -a "v$VERSION" -m "v$VERSION"
git push origin "v$VERSION"

# Update npm (cdnjs update automatically)
yarn publish --new-version "${VERSION}"

# Go back to original branch to bump
git checkout "$BRANCH"

if [ ! -z "$NEXT_VERSION" ]; then
    # Edit package.json to the next version
    sed -i.bak -E 's|"version": "[^"]+",|"version": "'$NEXT_VERSION'-pre",|' package.json
    rm -f package.json.bak
    git add package.json
fi

# Refer to the just-released version in the documentation of the
# development branch, too.  Most people will read docs on master.
git checkout "v${VERSION}" -- README.md contrib/*/README.md docs/*.md website/

if [[ -z "$NEXT_VERSION" ]]; then
    git commit -n -m "Release v$VERSION"
else
    git commit -n -m "Bump $BRANCH to v$NEXT_VERSION-pre"
fi

git push origin "$BRANCH"

# Go back to the tag which has katex.tar.gz and katex.zip
git checkout "v$VERSION"

echo ""
echo "The automatic parts are done!"

if [[ $BRANCH != "master" ]]; then
    echo "Now all that's left is to create a pull request against master from '$BRANCH'"
    echo "and to create the release on github."
else
    echo "Now all that's left is to create the release on github."
fi

echo "Visit https://github.com/Khan/KaTeX/releases/new?tag=v$VERSION to edit the release notes"
echo "Don't forget to upload katex.tar.gz and katex.zip to the release!"

if [[ ${DRY_RUN} ]]; then
    echo ""
    echo "This was a dry run."
    echo "Operations using git or yarn were printed not executed."
    echo "Some files got modified, though, so you might want to undo "
    echo "these changes now, e.g. using \`git checkout -- .\` or similar."
    echo ""
fi