#!/usr/bin/env bash
# Runs one Cargo command with one synchronized HCIE build-number increment.

set -euo pipefail

SCRIPT_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
ROOT_DIR="$(cd -- "${SCRIPT_DIR}/.." && pwd)"
LOCK_DIR="${ROOT_DIR}/.build-id.lock"
COUNTER_FILE="${ROOT_DIR}/build.id"

cleanup() {
    rm -rf -- "${LOCK_DIR}"
}

acquire_lock() {
    while ! mkdir -- "${LOCK_DIR}" 2>/dev/null; do
        if [[ -f "${LOCK_DIR}/pid" ]]; then
            local owner
            owner="$(<"${LOCK_DIR}/pid")"
            if [[ "${owner}" =~ ^[0-9]+$ ]] && ! kill -0 "${owner}" 2>/dev/null; then
                rm -rf -- "${LOCK_DIR}"
                continue
            fi
        fi
        sleep 0.05
    done
    printf '%s\n' "$$" > "${LOCK_DIR}/pid"
    trap cleanup EXIT INT TERM
}

write_counter() {
    local target="$1"
    local value="$2"
    local temporary="${target}.tmp.$$"
    printf '%s\n' "${value}" > "${temporary}"
    mv -f -- "${temporary}" "${target}"
}

if [[ $# -eq 0 ]]; then
    echo "usage: scripts/cargo-with-build-id.sh <cargo-subcommand> [arguments...]" >&2
    exit 2
fi

acquire_lock

if [[ -f "${COUNTER_FILE}" ]]; then
    current="$(tr -d '[:space:]' < "${COUNTER_FILE}")"
else
    current="0"
fi
if [[ ! "${current}" =~ ^[0-9]+$ ]]; then
    echo "build.id must contain one unsigned integer, found: ${current}" >&2
    exit 1
fi
if (( current >= 9223372036854775807 )); then
    echo "build.id reached the supported integer limit" >&2
    exit 1
fi

next=$((current + 1))
write_counter "${COUNTER_FILE}" "${next}"
write_counter "${ROOT_DIR}/hcie-egui-app/build.id" "${next}"
write_counter "${ROOT_DIR}/hcie-egui-app/crates/hcie-gui-egui/build.id" "${next}"

export HCIE_BUILD_ID_OVERRIDE="${next}"
echo "HCIE build ${next}: cargo $*"

cd -- "${ROOT_DIR}"
cargo "$@"