#!/usr/bin/env bash
# detect-platforms — probe available platform bridge dependencies
#
# Reports which el-native platform bridges can be built on this machine,
# with install instructions for anything that is missing.
#
# Usage: ./detect-platforms
#        ./build.sh platforms   (from native-hello)

set -uo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

# ── Helpers ───────────────────────────────────────────────────────────────────

PASS="[+]"
FAIL="[ ]"

_ok()   { printf "  ${PASS} %-22s %s\n" "$1" "$2"; }
_miss() { printf "  ${FAIL} %-22s %s\n" "$1" "$2"; }

# ── Header ────────────────────────────────────────────────────────────────────

echo ""
echo "==> el-native platform detection"
echo ""
echo "  Checking build dependencies for each platform bridge..."
echo ""

AVAILABLE=0
MISSING=0

# ── macOS / AppKit ────────────────────────────────────────────────────────────

if [[ "$(uname)" == "Darwin" ]]; then
    if xcrun --find clang &>/dev/null && xcrun --find xcodebuild &>/dev/null 2>/dev/null || \
       xcrun --find cc &>/dev/null; then
        CLT_INFO="Xcode CLT $(xcode-select -p 2>/dev/null | sed 's|/Developer||' || echo '')"
        _ok "macOS/AppKit" "-DEL_TARGET_MACOS  ${CLT_INFO}"
        AVAILABLE=$((AVAILABLE + 1))
    else
        _miss "macOS/AppKit" "-DEL_TARGET_MACOS  (Xcode CLT missing — xcode-select --install)"
        MISSING=$((MISSING + 1))
    fi
else
    _miss "macOS/AppKit" "-DEL_TARGET_MACOS  (not on macOS)"
fi

# ── iOS / UIKit ───────────────────────────────────────────────────────────────

if [[ "$(uname)" == "Darwin" ]]; then
    if xcrun --sdk iphoneos --show-sdk-path &>/dev/null 2>&1; then
        SDK_VER=$(xcrun --sdk iphoneos --show-sdk-version 2>/dev/null || echo "")
        _ok "iOS/UIKit" "-DEL_TARGET_IOS  SDK ${SDK_VER} (requires Xcode.app)"
        AVAILABLE=$((AVAILABLE + 1))
    else
        _miss "iOS/UIKit" "-DEL_TARGET_IOS  (iOS SDK not found — install Xcode.app)"
        MISSING=$((MISSING + 1))
    fi
else
    _miss "iOS/UIKit" "-DEL_TARGET_IOS  (not on macOS — requires Xcode)"
fi

# ── Linux / GTK4 ──────────────────────────────────────────────────────────────

if pkg-config --exists gtk4 2>/dev/null; then
    GTK_VER=$(pkg-config --modversion gtk4 2>/dev/null)
    _ok "Linux/GTK4" "-DEL_TARGET_LINUX  gtk4 ${GTK_VER}"
    AVAILABLE=$((AVAILABLE + 1))
else
    _miss "Linux/GTK4" "-DEL_TARGET_LINUX  (gtk4 not found)"
    echo "                             Install: apt install libgtk-4-dev"
    echo "                                   or: dnf install gtk4-devel"
    echo "                                   or: brew install gtk4"
    MISSING=$((MISSING + 1))
fi

# ── SDL2 / Embedded Linux / Pi ────────────────────────────────────────────────

SDL2_OK=0
if pkg-config --exists sdl2 2>/dev/null; then
    SDL2_VER=$(pkg-config --modversion sdl2 2>/dev/null)
    # Also check for SDL2_ttf (needed for text rendering)
    if pkg-config --exists SDL2_ttf 2>/dev/null; then
        TTF_VER=$(pkg-config --modversion SDL2_ttf 2>/dev/null)
        _ok "SDL2/Embedded" "-DEL_TARGET_SDL2  sdl2 ${SDL2_VER}, SDL2_ttf ${TTF_VER}"
    else
        _ok "SDL2/Embedded" "-DEL_TARGET_SDL2  sdl2 ${SDL2_VER} (SDL2_ttf missing — needed for text)"
        echo "                             Install: apt install libsdl2-ttf-dev"
    fi
    SDL2_OK=1
    AVAILABLE=$((AVAILABLE + 1))
elif command -v sdl2-config &>/dev/null; then
    SDL2_VER=$(sdl2-config --version 2>/dev/null || echo "")
    _ok "SDL2/Embedded" "-DEL_TARGET_SDL2  sdl2 ${SDL2_VER} (via sdl2-config)"
    SDL2_OK=1
    AVAILABLE=$((AVAILABLE + 1))
fi

if [[ $SDL2_OK -eq 0 ]]; then
    _miss "SDL2/Embedded" "-DEL_TARGET_SDL2  (sdl2 not found)"
    echo "                             Install: apt install libsdl2-dev libsdl2-ttf-dev libsdl2-image-dev"
    echo "                                   or: brew install sdl2 sdl2_ttf sdl2_image"
    MISSING=$((MISSING + 1))
fi

# ── LVGL / Microcontrollers ───────────────────────────────────────────────────

LVGL_OK=0
LVGL_WHERE=""

if [ -f "${SCRIPT_DIR}/lvgl/lvgl.h" ]; then
    LVGL_WHERE="./lvgl/lvgl.h"
    LVGL_OK=1
elif [ -f "${SCRIPT_DIR}/../lvgl/lvgl.h" ]; then
    LVGL_WHERE="adjacent lvgl/"
    LVGL_OK=1
elif [ -f "/usr/include/lvgl/lvgl.h" ]; then
    LVGL_WHERE="/usr/include/lvgl"
    LVGL_OK=1
elif [ -f "/usr/local/include/lvgl/lvgl.h" ]; then
    LVGL_WHERE="/usr/local/include/lvgl"
    LVGL_OK=1
elif pkg-config --exists lvgl 2>/dev/null; then
    LVGL_WHERE="pkg-config ($(pkg-config --modversion lvgl 2>/dev/null))"
    LVGL_OK=1
fi

if [[ $LVGL_OK -eq 1 ]]; then
    _ok "LVGL/MCU" "-DEL_TARGET_LVGL  ${LVGL_WHERE}"
    AVAILABLE=$((AVAILABLE + 1))
else
    _miss "LVGL/MCU" "-DEL_TARGET_LVGL  (lvgl.h not found)"
    echo "                             Install: git clone https://github.com/lvgl/lvgl"
    echo "                                      (place lvgl/ next to el-compiler/runtime/)"
    MISSING=$((MISSING + 1))
fi

# ── Android / JNI ─────────────────────────────────────────────────────────────

ANDROID_OK=0
ANDROID_WHERE=""

if [ -n "${ANDROID_NDK_HOME:-}" ] && [ -d "${ANDROID_NDK_HOME}" ]; then
    NDK_VER=""
    if [ -f "${ANDROID_NDK_HOME}/source.properties" ]; then
        NDK_VER=$(grep "Pkg.Revision" "${ANDROID_NDK_HOME}/source.properties" \
                  2>/dev/null | cut -d= -f2 | tr -d ' ' || echo "")
    fi
    ANDROID_WHERE="NDK ${NDK_VER:-(version unknown)} at \$ANDROID_NDK_HOME"
    ANDROID_OK=1
elif command -v ndk-build &>/dev/null; then
    ANDROID_WHERE="ndk-build in PATH"
    ANDROID_OK=1
elif [ -n "${ANDROID_HOME:-}" ] && [ -d "${ANDROID_HOME}/ndk" ]; then
    ANDROID_WHERE="NDK via \$ANDROID_HOME/ndk"
    ANDROID_OK=1
fi

if [[ $ANDROID_OK -eq 1 ]]; then
    _ok "Android/JNI" "-DEL_TARGET_ANDROID  ${ANDROID_WHERE}"
    AVAILABLE=$((AVAILABLE + 1))
else
    _miss "Android/JNI" "-DEL_TARGET_ANDROID  (ANDROID_NDK_HOME not set)"
    echo "                             Install: https://developer.android.com/studio/releases/ndk"
    echo "                             Then: export ANDROID_NDK_HOME=/path/to/ndk"
    MISSING=$((MISSING + 1))
fi

# ── Windows / Win32 (cross or native) ─────────────────────────────────────────

WIN32_OK=0
WIN32_WHERE=""

if [[ "$(uname)" == MINGW* ]] || [[ "$(uname)" == CYGWIN* ]] || \
   [[ "$(uname)" == MSYS* ]]; then
    WIN32_WHERE="native Windows ($(uname))"
    WIN32_OK=1
elif command -v x86_64-w64-mingw32-gcc &>/dev/null; then
    MINGW_VER=$(x86_64-w64-mingw32-gcc --version 2>/dev/null | head -1 || echo "")
    WIN32_WHERE="mingw cross-compiler — ${MINGW_VER}"
    WIN32_OK=1
elif command -v i686-w64-mingw32-gcc &>/dev/null; then
    WIN32_WHERE="mingw 32-bit cross-compiler"
    WIN32_OK=1
fi

if [[ $WIN32_OK -eq 1 ]]; then
    _ok "Windows/Win32" "-DEL_TARGET_WIN32  ${WIN32_WHERE}"
    AVAILABLE=$((AVAILABLE + 1))
else
    _miss "Windows/Win32" "-DEL_TARGET_WIN32  (mingw cross-compiler not found)"
    echo "                             Install: brew install mingw-w64"
    echo "                                   or: apt install gcc-mingw-w64"
    MISSING=$((MISSING + 1))
fi

# ── Summary ───────────────────────────────────────────────────────────────────

echo ""
echo "  ${AVAILABLE} platform(s) available, ${MISSING} unavailable on this machine."
echo ""

if [[ -x "${SCRIPT_DIR}/new-platform" ]]; then
    echo "  Scaffold a new bridge:  ${SCRIPT_DIR}/new-platform <name>"
fi
echo "  Bridge contract:        ${SCRIPT_DIR}/PLATFORM_BRIDGE_SPEC.md"
echo ""