#!/bin/sh

# Check dependencies
check_command() {
    command -v "$1" > /dev/null 2>&1 || { echo "git-stats hook script requires the \`${1}\` binary in order to run." >&2; exit 1; }
}

check_command "perl"
check_command "printf"
check_command "git"

echo "Setting up git-stats hooks.";

# Create a new global templatedir if there are none
git_templates_dir=$(git config --global --get init.templatedir);
if [ $? -ne 0 ]; then
    # Create a new global templatedir if there are none
    git_templates_dir="${HOME}/.git-templates"
    git config --global init.templatedir "$git_templates_dir" && echo "Set new global git template dir at ${git_templates_dir}"
fi
git_hooks_dir="${git_templates_dir}/hooks"
post_commit_path="${git_hooks_dir}/post-commit"

mkdir -p "$git_hooks_dir"

# Create the post-commit file content
hook=$(cat <<EOF
### git-stats hook (begin) ###
# Copy last commit hash to clipboard on commit
commit_hash=\$(git rev-parse HEAD)
repo_url=\$(git config --get remote.origin.url)
commit_date=\$(git log -1 --format=%cd)
commit_data="\"{ \"date\": \"\$commit_date\", \"url\": \"\$repo_url\", \"hash\": \"\$commit_hash\" }\""
git-stats --record "\${commit_data}"
### git-stats hook (end) ###
EOF
);

if [ ! -f "$post_commit_path" ]; then
    printf "#!/bin/sh\n%s" "$hook" > "$post_commit_path" \
        && chmod +x "$post_commit_path" \
        && echo "Successfully set up git-stats hook at ${post_commit_path}." \
        && exit 0
else
    # Remove any previous git-stats hook code blocks
    perl -i -0pe 's/(([ \t]*# Copy last commit hash to clipboard on commit\s*(\n.*){5}\s*git-stats --record "\$commit_data"\s*)|([ \t]*### git-stats hook \(begin\) ###\s*(\n.*){7}\s*### git-stats hook \(end\) ###\s*))//g' "$post_commit_path"
    printf "%s\n" "$hook" >> "$post_commit_path" \
        && echo "Successfully set up git-stats hook at ${post_commit_path}." \
        && exit 0
fi

echo "Couldn't set up git-stats hook."
exit 1