#!/bin/bash

set -e

if test "${#}" -lt 1 || test "${#}" -gt 2; then
    printf "%s\n" "usage: $(basename $0) <reponame> [section]"
    exit 1
fi

REPO_NAME="${1}"
if ! [[ "${REPO_NAME}" =~ ^[a-zA-Z0-9_-]+$ ]]; then
    printf "%s\n" "[err] repository name can only contain letters, numbers, underscores, and hyphens"
    exit 1
fi

REPO_SECTION="${2:-uncategorized}"
if ! [[ "${REPO_SECTION}" =~ ^[a-zA-Z0-9_-]+$ ]]; then
    printf "%s\n" "[err] section can only contain letters, numbers, underscores, and hyphens"
    exit 1
fi

REPO_DIR="/srv/git/repos/${REPO_NAME}.git"
if test -d "${REPO_DIR}"; then
    printf "%s\n" "[err] repository ${REPO_NAME}.git already exists at ${REPO_DIR}"
    exit 1
fi

mkdir -p "${REPO_DIR}" &>/dev/null
(
    cd "${REPO_DIR}"
    if git init --bare &>/dev/null; then
        printf "%s\n" "[inf] created bare repository at ${REPO_DIR}"
    else
        printf "%s\n" "[err] failed to create bare repository at ${REPO_DIR}"
    fi

    git config core.logallrefupdates true

    EMPTY_TREE=$(git hash-object -t tree /dev/null)
    COMMIT=$(printf "%s\n" "initial commit" | git commit-tree "${EMPTY_TREE}")
    git update-ref refs/heads/main "${COMMIT}"
    git symbolic-ref HEAD refs/heads/main
    git update-server-info
    git config cgit.section "${REPO_SECTION}"

    cat > hooks/post-receive << "EOL"
#!/bin/sh

agefile="$(git rev-parse --git-dir)"/info/web/last-modified

mkdir -p "$(dirname "$agefile")" &&
git for-each-ref \
        --sort=-authordate --count=1 \
        --format='%(authordate:iso8601)' \
        >"$agefile"
EOL
    chmod +x hooks/post-receive
)

chown -R git:git "${REPO_DIR}"
chmod -R g-w "${REPO_DIR}"

printf "%s\n" "[inf] clone with git clone https://cgit.heqnx.com/${REPO_NAME}"