#!/bin/bash
set -euo pipefail

# Builds shadowhook as a static library for Android arm64.
# Produces: libs/libshadowhook.a and libs/libshadowhook_nothing.so

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
PROJECT_DIR="$(dirname "$SCRIPT_DIR")"
BUILD_DIR="$PROJECT_DIR/build/deps"
mkdir -p "$BUILD_DIR"

# --- Auto-detect Android NDK (same logic as build.sh) ---
find_ndk() {
    if [ -n "${ANDROID_NDK_HOME:-}" ] && [ -d "$ANDROID_NDK_HOME" ]; then
        echo "$ANDROID_NDK_HOME"; return
    fi
    local brew_ndk
    brew_ndk=$(find /opt/homebrew /usr/local -path "*/android-ndk/*/toolchains/llvm/prebuilt" -type d 2>/dev/null | head -1)
    if [ -n "$brew_ndk" ]; then
        echo "$(dirname "$(dirname "$(dirname "$brew_ndk")")")"; return
    fi
    local sdk_ndk
    sdk_ndk=$(find "$HOME/Library/Android/sdk/ndk" -maxdepth 1 -type d 2>/dev/null | sort -V | tail -1)
    if [ -n "$sdk_ndk" ] && [ -d "$sdk_ndk" ]; then
        echo "$sdk_ndk"; return
    fi
    for p in /opt/android-ndk /usr/local/android-ndk "$HOME/android-ndk"; do
        if [ -d "$p" ]; then echo "$p"; return; fi
    done
    echo ""
}

NDK_HOME="$(find_ndk)"
API_LEVEL="${ANDROID_API_LEVEL:-21}"
CC=""
if [ -n "$NDK_HOME" ]; then
    CC=$(find "$NDK_HOME/toolchains/llvm/prebuilt" -type f \
        -name "aarch64-linux-android${API_LEVEL}-clang" -print -quit 2>/dev/null)
fi
if [ -z "$CC" ]; then
    echo "ERROR: aarch64-linux-android clang not found."
    echo "  Set ANDROID_NDK_HOME to your NDK path."
    exit 1
fi

TOOLCHAIN_DIR="$(dirname "$CC")"
AR="$TOOLCHAIN_DIR/llvm-ar"
CFLAGS="-O2 -ffunction-sections -fdata-sections -fPIC -DANDROID -Wall -Wextra -Wno-unused-parameter -Wno-unused-function"

OUT_DIR="$SCRIPT_DIR"

echo "=== Building shadowhook (arm64-v8a) ==="

SH="$SCRIPT_DIR/shadowhook/shadowhook/src/main/cpp"

SH_SRCS="
$SH/sh_elf.c
$SH/sh_enter.c
$SH/sh_hub.c
$SH/sh_island.c
$SH/sh_linker.c
$SH/sh_recorder.c
$SH/sh_safe.c
$SH/sh_switch.c
$SH/sh_task.c
$SH/sh_xdl.c
$SH/shadowhook.c
$SH/arch/arm64/sh_a64.c
$SH/arch/arm64/sh_inst.c
$SH/arch/arm64/sh_glue.S
$SH/common/bytesig.c
$SH/common/sh_errno.c
$SH/common/sh_log.c
$SH/common/sh_ref.c
$SH/common/sh_trampo.c
$SH/common/sh_util.c
$SH/third_party/xdl/xdl.c
$SH/third_party/xdl/xdl_iterate.c
$SH/third_party/xdl/xdl_linker.c
$SH/third_party/xdl/xdl_lzma.c
$SH/third_party/xdl/xdl_util.c
"

SH_INCLUDES="
-I$SH
-I$SH/include
-I$SH/arch/arm64
-I$SH/common
-I$SH/third_party/xdl
-I$SH/third_party/bsd
-I$SH/third_party/lss
"

SH_OBJS=""
for src in $SH_SRCS; do
    [ -z "$src" ] && continue
    src=$(echo "$src" | xargs)
    if [ ! -f "$src" ]; then
        echo "ERROR: shadowhook source not found: $src"
        exit 1
    fi

    basename=$(echo "$src" | sed "s|$SH/||" | tr '/' '_')
    obj="$BUILD_DIR/sh_${basename%.c}.o"
    obj="${obj%.S.o}.o"

    if [[ "$src" == *.S ]]; then
        "$CC" $CFLAGS $SH_INCLUDES -c "$src" -o "$obj"
    else
        "$CC" $CFLAGS $SH_INCLUDES -c "$src" -o "$obj"
    fi
    SH_OBJS="$SH_OBJS $obj"
done

if [ -z "$SH_OBJS" ]; then
    echo "ERROR: shadowhook produced no object files."
    exit 1
fi

"$AR" rcs "$OUT_DIR/libshadowhook.a" $SH_OBJS
SH_SIZE=$(wc -c < "$OUT_DIR/libshadowhook.a" 2>/dev/null || echo "unknown")
echo "  Built $OUT_DIR/libshadowhook.a ($SH_SIZE bytes)"

NOTHING_SRC="$SH/nothing/sh_nothing.c"
if [ ! -f "$NOTHING_SRC" ]; then
    echo "ERROR: ShadowHook companion source not found: $NOTHING_SRC"
    exit 1
fi

"$CC" -shared -Oz -fPIC -fno-ident -fno-unwind-tables -fno-asynchronous-unwind-tables \
    -nostdlib -nostartfiles -nodefaultlibs \
    -Wl,-z,max-page-size=16384 \
    -Wl,--strip-all -Wl,--as-needed -Wl,--hash-style=sysv \
    -Wl,--build-id=none \
    -o "$OUT_DIR/libshadowhook_nothing.so" "$NOTHING_SRC"
echo "  Built $OUT_DIR/libshadowhook_nothing.so"