#!/usr/bin/env bash
set -euo pipefail

# ============================================================
# build.sh — dstalk cross-platform build script (Linux / macOS)
# Mirrors build.bat; installs tools into tools/ if missing,
# then runs Conan + CMake + Ninja without modifying system PATH.
# ============================================================

ROOT="$(cd "$(dirname "$0")" && pwd)"
TOOLS="${ROOT}/tools"
BUILD_DIR="${ROOT}/build"
BUILD_TYPE="${1:-Release}"

echo "[dstalk] Build type: ${BUILD_TYPE}"
echo "[dstalk] Project root: ${ROOT}"

# ============================================================
# 1. Detect / resolve tool paths (prefer tools/, fallback PATH)
# ============================================================

find_tool() {
    local name="$1"
    shift
    for candidate in "$@"; do
        if [ -x "$candidate" ]; then
            echo "$candidate"
            return 0
        fi
    done
    local sys
    sys=$(command -v "$name" 2>/dev/null || true)
    if [ -n "$sys" ]; then
        echo "$sys"
        return 0
    fi
    return 1
}

CMAKE_EXE=$(find_tool cmake "${TOOLS}/cmake/bin/cmake") || {
    echo "  [ERROR] CMake not found. Run: tools/setup.sh"
    exit 1
}
NINJA_EXE=$(find_tool ninja "${TOOLS}/ninja/ninja") || {
    echo "  [ERROR] Ninja not found. Run: tools/setup.sh"
    exit 1
}
CONAN_EXE=$(find_tool conan "${TOOLS}/.venv/bin/conan") || {
    echo "  [ERROR] Conan2 not found. Run: tools/setup.sh"
    exit 1
}

# Compiler: prefer clang, fallback gcc
if [ "$(uname)" = "Darwin" ]; then
    CC_EXE=$(find_tool clang "${TOOLS}/llvm/bin/clang") || CC_EXE="clang"
    CXX_EXE=$(find_tool clang++ "${TOOLS}/llvm/bin/clang++") || CXX_EXE="clang++"
else
    CC_EXE=$(find_tool clang "${TOOLS}/llvm/bin/clang") || \
        CC_EXE=$(find_tool gcc) || { echo "  [ERROR] No C compiler found"; exit 1; }
    CXX_EXE=$(find_tool clang++ "${TOOLS}/llvm/bin/clang++") || \
        CXX_EXE=$(find_tool g++) || { echo "  [ERROR] No C++ compiler found"; exit 1; }
fi

echo "[dstalk] CMake:    ${CMAKE_EXE}"
echo "[dstalk] Ninja:    ${NINJA_EXE}"
echo "[dstalk] Conan:    ${CONAN_EXE}"
echo "[dstalk] CC:       ${CC_EXE}"
echo "[dstalk] CXX:      ${CXX_EXE}"

# ============================================================
# 2. Conan install dependencies
# ============================================================
echo "[dstalk] Conan: installing dependencies..."
"${CONAN_EXE}" install deps/ -of "${BUILD_DIR}" --build=missing \
    -s build_type="${BUILD_TYPE}" \
    -c tools.cmake.cmaketoolchain:generator=Ninja

# Locate the conan toolchain
CONAN_TOOLCHAIN=""
for candidate in \
    "${BUILD_DIR}/build/${BUILD_TYPE}/generators/conan_toolchain.cmake" \
    "${BUILD_DIR}/${BUILD_TYPE}/generators/conan_toolchain.cmake" \
    "${BUILD_DIR}/${BUILD_TYPE}/conan_toolchain.cmake" \
    "${BUILD_DIR}/conan_toolchain.cmake"; do
    if [ -f "$candidate" ]; then
        CONAN_TOOLCHAIN="$candidate"
        break
    fi
done

if [ -z "${CONAN_TOOLCHAIN}" ]; then
    echo "  [ERROR] Could not find conan_toolchain.cmake"
    echo "  Searched in: ${BUILD_DIR}/build/${BUILD_TYPE}/generators/"
    echo "               ${BUILD_DIR}/${BUILD_TYPE}/generators/"
    exit 1
fi
echo "[dstalk] Conan toolchain: ${CONAN_TOOLCHAIN}"
CONAN_PREFIX_PATH="$(dirname "${CONAN_TOOLCHAIN}")"

# Patch conan toolchain if it hardcodes 'cl' (Windows-generated)
if grep -q 'set(CMAKE_C_COMPILER "cl")' "${CONAN_TOOLCHAIN}" 2>/dev/null; then
    echo "[dstalk] Patching conan toolchain: replacing cl -> detected compiler"
    sed -i.bak \
        -e "s|set(CMAKE_C_COMPILER \"cl\")|set(CMAKE_C_COMPILER \"${CC_EXE}\")|" \
        -e "s|set(CMAKE_CXX_COMPILER \"cl\")|set(CMAKE_CXX_COMPILER \"${CXX_EXE}\")|" \
        "${CONAN_TOOLCHAIN}"
fi

# ============================================================
# 3. CMake configure + Ninja build
# ============================================================
echo "[dstalk] CMake configure..."
"${CMAKE_EXE}" -S "${ROOT}" -B "${BUILD_DIR}" -G Ninja \
    -DCMAKE_MAKE_PROGRAM="${NINJA_EXE}" \
    -DCMAKE_C_COMPILER="${CC_EXE}" \
    -DCMAKE_CXX_COMPILER="${CXX_EXE}" \
    -DCMAKE_TOOLCHAIN_FILE="${CONAN_TOOLCHAIN}" \
    -DCMAKE_PREFIX_PATH="${CONAN_PREFIX_PATH}" \
    -DCMAKE_BUILD_TYPE="${BUILD_TYPE}" \
    -DDSTALK_BUILD_GUI=OFF

echo "[dstalk] Building..."
"${CMAKE_EXE}" --build "${BUILD_DIR}"

echo ""
echo "============================================"
echo "  Build succeeded!"
echo "  ${BUILD_DIR}/bin/dstalk$([ "$(uname)" = 'Darwin' ] && echo '.dylib' || echo '.so')"
echo "  ${BUILD_DIR}/bin/dstalk_cli"
echo "============================================"