Dockerfile.android

# Dockerfile.android — cross-compile android-arm64 static libraries via Android NDK
#
# Usage:
#   docker build -f Dockerfile.android -o ./out .
#
# Build + link test (ensures .a files cross-link correctly with Go CGO):
#   docker build -f Dockerfile.android --target build-test .
#
# This extracts prebuilt .a files + headers for android-arm64 into ./out/.

# ============================================================================
# Stage: Download sources
# ============================================================================
FROM golang:1.24-bookworm AS sources

RUN apt-get update && apt-get install -y --no-install-recommends \
    wget && \
    rm -rf /var/lib/apt/lists/*

WORKDIR /src

# Copy version files so we can read versions from Go
COPY go.mod ./
COPY version.go ./
COPY cmd/versioncmd/ ./cmd/versioncmd/

# Download llama.cpp
RUN LLAMA_VERSION=$(go run ./cmd/versioncmd llama.cpp) && \
    echo "Downloading llama.cpp ${LLAMA_VERSION}..." && \
    wget -qO llama.cpp.tar.gz "https://github.com/ggerganov/llama.cpp/archive/refs/tags/${LLAMA_VERSION}.tar.gz" && \
    mkdir -p llama-src && \
    tar xzf llama.cpp.tar.gz --strip-components=1 -C llama-src && \
    rm llama.cpp.tar.gz

# Download whisper.cpp
RUN WHISPER_VERSION=$(go run ./cmd/versioncmd whisper.cpp) && \
    echo "Downloading whisper.cpp ${WHISPER_VERSION}..." && \
    wget -qO whisper.cpp.tar.gz "https://github.com/ggerganov/whisper.cpp/archive/refs/tags/${WHISPER_VERSION}.tar.gz" && \
    mkdir -p whisper-src && \
    tar xzf whisper.cpp.tar.gz --strip-components=1 -C whisper-src && \
    rm whisper.cpp.tar.gz

# ============================================================================
# Builder: Android ARM64 via NDK
# ============================================================================
FROM golang:1.24-bookworm AS builder

RUN apt-get update && apt-get install -y --no-install-recommends \
    build-essential cmake wget unzip && \
    rm -rf /var/lib/apt/lists/*

# Install Android NDK r27c
ARG NDK_VERSION=r27c
RUN wget -qO ndk.zip "https://dl.google.com/android/repository/android-ndk-${NDK_VERSION}-linux.zip" && \
    unzip -q ndk.zip -d /opt && \
    rm ndk.zip
ENV ANDROID_NDK_HOME=/opt/android-ndk-${NDK_VERSION}

WORKDIR /src
COPY --from=sources /src/llama-src llama-src
COPY --from=sources /src/whisper-src whisper-src

# NDK strip tool for removing debug symbols from .a files
ENV NDK_STRIP=${ANDROID_NDK_HOME}/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-strip

# Build llama.cpp for android-arm64
RUN cd llama-src && \
    cmake -B build \
        -DCMAKE_TOOLCHAIN_FILE=${ANDROID_NDK_HOME}/build/cmake/android.toolchain.cmake \
        -DANDROID_ABI=arm64-v8a \
        -DANDROID_PLATFORM=android-28 \
        -DCMAKE_BUILD_TYPE=Release \
        -DBUILD_SHARED_LIBS=OFF \
        -DGGML_OPENMP=OFF && \
    cmake --build build --config Release -j$(nproc)

# Build whisper.cpp for android-arm64
RUN cd whisper-src && \
    cmake -B build \
        -DCMAKE_TOOLCHAIN_FILE=${ANDROID_NDK_HOME}/build/cmake/android.toolchain.cmake \
        -DANDROID_ABI=arm64-v8a \
        -DANDROID_PLATFORM=android-28 \
        -DCMAKE_BUILD_TYPE=Release \
        -DBUILD_SHARED_LIBS=OFF \
        -DGGML_OPENMP=OFF && \
    cmake --build build --config Release -j$(nproc)

# Collect llama.cpp artifacts and strip debug symbols
RUN mkdir -p /out/llama.cpp/android-arm64 /out/llama.cpp/include /out/llama.cpp/ggml/include /out/llama.cpp/common && \
    find llama-src/build -name "*.a" -exec cp {} /out/llama.cpp/android-arm64/ \; && \
    find /out/llama.cpp/android-arm64 -name "*.a" -exec ${NDK_STRIP} --strip-debug {} \; && \
    cp llama-src/include/*.h /out/llama.cpp/include/ && \
    cp llama-src/ggml/include/*.h /out/llama.cpp/ggml/include/ && \
    cp llama-src/common/common.h /out/llama.cpp/common/ && \
    cp llama-src/common/sampling.h /out/llama.cpp/common/ && \
    cp llama-src/tools/mtmd/mtmd.h /out/llama.cpp/include/ && \
    cp llama-src/tools/mtmd/mtmd-helper.h /out/llama.cpp/include/

# Collect whisper.cpp artifacts and strip debug symbols
RUN mkdir -p /out/whisper.cpp/android-arm64 /out/whisper.cpp/include /out/whisper.cpp/ggml/include && \
    find whisper-src/build -name "*.a" -exec cp {} /out/whisper.cpp/android-arm64/ \; && \
    find /out/whisper.cpp/android-arm64 -name "*.a" -exec ${NDK_STRIP} --strip-debug {} \; && \
    cp whisper-src/include/*.h /out/whisper.cpp/include/ && \
    cp whisper-src/ggml/include/*.h /out/whisper.cpp/ggml/include/

# ============================================================================
# Build test — verifies .a files cross-link correctly with Go CGO + NDK
# ============================================================================
FROM golang:1.24-bookworm AS build-test

RUN apt-get update && apt-get install -y --no-install-recommends \
    build-essential wget unzip && \
    rm -rf /var/lib/apt/lists/*

# Install Android NDK (same version as builder)
ARG NDK_VERSION=r27c
RUN wget -qO ndk.zip "https://dl.google.com/android/repository/android-ndk-${NDK_VERSION}-linux.zip" && \
    unzip -q ndk.zip -d /opt && \
    rm ndk.zip
ENV ANDROID_NDK_HOME=/opt/android-ndk-${NDK_VERSION}

# NDK toolchain paths
ENV NDK_TOOLCHAIN=${ANDROID_NDK_HOME}/toolchains/llvm/prebuilt/linux-x86_64
ENV CC_android_arm64=${NDK_TOOLCHAIN}/bin/aarch64-linux-android28-clang
ENV CXX_android_arm64=${NDK_TOOLCHAIN}/bin/aarch64-linux-android28-clang++

WORKDIR /src
COPY . .

# Copy freshly built .a files and headers into the source tree
COPY --from=builder /out/llama.cpp/android-arm64/ /src/ggml/llamacpp/third_party/prebuilt/android-arm64/
COPY --from=builder /out/llama.cpp/include/ /src/ggml/llamacpp/third_party/include/
COPY --from=builder /out/llama.cpp/ggml/include/ /src/ggml/llamacpp/third_party/ggml/include/
COPY --from=builder /out/llama.cpp/common/ /src/ggml/llamacpp/third_party/common/
COPY --from=builder /out/whisper.cpp/android-arm64/ /src/ggml/whispercpp/third_party/prebuilt/android-arm64/
COPY --from=builder /out/whisper.cpp/include/ /src/ggml/whispercpp/third_party/include/
COPY --from=builder /out/whisper.cpp/ggml/include/ /src/ggml/whispercpp/third_party/ggml/include/

# Verify stub builds (no tags, no CGO)
RUN CGO_ENABLED=0 go build ./ggml/llamacpp/... && \
    CGO_ENABLED=0 go build ./ggml/whispercpp/... && \
    echo "stub builds OK"

# Verify CGO cross-compilation links against android-arm64 .a files
RUN CGO_ENABLED=1 \
    GOOS=android \
    GOARCH=arm64 \
    CC=${CC_android_arm64} \
    CXX=${CXX_android_arm64} \
    go build -tags llamacpp ./ggml/llamacpp/... && \
    echo "llamacpp android-arm64 CGO build OK"

RUN CGO_ENABLED=1 \
    GOOS=android \
    GOARCH=arm64 \
    CC=${CC_android_arm64} \
    CXX=${CXX_android_arm64} \
    go build -tags whispercpp ./ggml/whispercpp/... && \
    echo "whispercpp android-arm64 CGO build OK"

# Run stub tests
RUN CGO_ENABLED=0 go test ./ggml/llamacpp/... && \
    CGO_ENABLED=0 go test ./ggml/whispercpp/... && \
    echo "all tests passed"

# ============================================================================
# Output stage — docker build -o extracts from here
# ============================================================================
FROM scratch
COPY --from=builder /out/ /