#!/usr/bin/env bash
#
# run_tests.sh -- Build and run host-side unit and system tests
#
# Usage:
#   ./test/run_tests.sh              Build and run all tests
#   ./test/run_tests.sh --clean      Clean rebuild
#   ./test/run_tests.sh --verbose    Verbose test output
#   ./test/run_tests.sh --filter X   Run only tests matching X
#
# Prerequisites:
#   cmake >= 3.14, g++ or clang++, git (for fetching gtest)
#
# First run will download Google Test (~30 seconds).

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
BUILD_DIR="$SCRIPT_DIR/build"

# Color output
if [[ -t 1 ]]; then
    RED=$'\033[0;31m'; GRN=$'\033[0;32m'; CYN=$'\033[0;36m'
    BLD=$'\033[1m';    RST=$'\033[0m'
else
    RED=''; GRN=''; CYN=''; BLD=''; RST=''
fi

info() { echo -e "${CYN}[TEST]${RST}  $*"; }
ok()   { echo -e "${GRN}[PASS]${RST}  $*"; }
die()  { echo -e "${RED}[FAIL]${RST}  $*" >&2; exit 1; }

# Parse args
DO_CLEAN=0
VERBOSE=""
FILTER=""

for arg in "$@"; do
    case "$arg" in
        --clean)    DO_CLEAN=1 ;;
        --verbose)  VERBOSE="--verbose" ;;
        --filter)   : ;;  # next arg is the pattern
        -*)         die "Unknown option: $arg" ;;
        *)          FILTER="$arg" ;;
    esac
done

# Check prerequisites
command -v cmake &>/dev/null || die "cmake not found. Install: sudo apt install cmake"
command -v g++ &>/dev/null || command -v clang++ &>/dev/null || die "No C++ compiler found"
command -v git &>/dev/null || die "git not found (needed to fetch Google Test)"

# Clean if requested
if [[ $DO_CLEAN -eq 1 ]] && [[ -d "$BUILD_DIR" ]]; then
    info "Cleaning build directory..."
    rm -rf "$BUILD_DIR"
fi

# Configure
if [[ ! -f "$BUILD_DIR/CMakeCache.txt" ]]; then
    info "Configuring (first run will fetch Google Test)..."
    cmake -S "$SCRIPT_DIR" -B "$BUILD_DIR" -DCMAKE_BUILD_TYPE=Debug
fi

# Build
info "Building tests..."
cmake --build "$BUILD_DIR" --parallel

# Run
echo ""
info "${BLD}Running tests...${RST}"
echo ""

CTEST_ARGS=("--test-dir" "$BUILD_DIR" "--output-on-failure")
[[ -n "$VERBOSE" ]] && CTEST_ARGS+=("--verbose")
[[ -n "$FILTER" ]]  && CTEST_ARGS+=("-R" "$FILTER")

if ctest "${CTEST_ARGS[@]}"; then
    echo ""
    ok "${BLD}All tests passed.${RST}"
else
    echo ""
    die "Some tests failed."
fi