FROM debian:oldstable-slim

# Build- based container for ImGui repository
# Install essential build tools and dependencies
RUN set -eux; \
    apt-get update; \
    apt-get install -y --no-install-recommends \
        build-essential \
        cmake \
        libglfw3-dev \
        libsdl2-dev \
        gcc-multilib \
        g++-multilib \
        libfreetype6-dev \
        libvulkan-dev \
        pkg-config; \
    rm -rf /var/lib/apt/lists/*

# Copy source into the image
WORKDIR /imgui
COPY . /imgui

# Configure and build from source. We try to disable building additional examples to keep build lightweight
RUN cmake -S . -B build -DCMAKE_BUILD_TYPE=Release \
        -DIMGUI_BUILD_EXAMPLES=OFF || true
RUN cmake --build build -j$(nproc)

# Provide a shell to inspect the image when running in interactive mode
CMD ["/bin/bash"]

- Exact error message and exit code
  - Final failure: process "/bin/sh -c cmake --build build -j$(nproc)" did not complete successfully: exit code: 1
  - Intermediate error (masked by || true): CMake Error: The source directory "/imgui" does not appear to contain CMakeLists.txt.
  - Additional failure detail: Error: /imgui/build is not a directory

- Failing command/step
  - Step [5/6] RUN cmake -S . -B build -DCMAKE_BUILD_TYPE=Release         -DIMGUI_BUILD_EXAMPLES=OFF || true
  - Step [6/6] RUN cmake --build build -j$(nproc)

- Missing packages or files mentioned
  - The source directory for CMake is /imgui and is missing a CMakeLists.txt (CMake error above).
  - Because /imgui/build was not created as a directory due to the missing CMakeLists.txt, the final build step fails with “Error: /imgui/build is not a directory”.

- Version mismatch information
  - Base image used: Debian oldstable (FROM debian:oldstable-slim), which can imply an older toolchain not aligned with the required CMake/BUILD setup. No explicit version mismatch error is shown beyond the base image choice.

FROM debian:oldstable-slim

# Build- based container for ImGui repository (Linux)
# Install essential build tools and dependencies
RUN set -eux; \
    apt-get update; \
    apt-get install -y --no-install-recommends \
        build-essential \
        gcc-multilib \
        g++-multilib \
        libglfw3-dev \
        libsdl2-dev \
        libfreetype6-dev \
        libvulkan-dev \
        pkg-config \
        make \
        ca-certificates; \
    rm -rf /var/lib/apt/lists/*

# Copy source into the image
WORKDIR /imgui
COPY . /imgui

# Build a representative Linux target from source (example_null)
# The repository uses Makefiles for Linux builds (as in GitHub Actions workflow).
RUN set -eux; \
    cd examples/example_null; \
    make clean; \
    WITH_EXTRA_WARNINGS=1 make

# Provide a shell to inspect the image when running in interactive mode
CMD ["/bin/bash"]

FROM debian:oldstable-slim

# Linux build environment for ImGui repository (Make-based Linux build)
RUN set -eux; \
    apt-get update; \
    # Install essential build tools and dependencies
    apt-get install -y --no-install-recommends \
        build-essential \
        gcc-multilib \
        g++-multilib \
        libglfw3-dev \
        libsdl2-dev \
        libfreetype6-dev \
        libvulkan-dev \
        pkg-config \
        make \
        ca-certificates; \
    rm -rf /var/lib/apt/lists/*

# Copy source into the image
WORKDIR /imgui
COPY . /imgui

# Build Linux example_null from source
RUN set -eux; \
    cd examples/example_null; \
    make clean; \
    WITH_EXTRA_WARNINGS=1 make

# Create a predictable entry path for smoke tests: /imgui/example_null -> built executable
RUN set -eux; \
    EXE=$(find /imgui -type f -name example_null -executable -print -quit 2>/dev/null || true); \
    if [ -n "$EXE" ]; then \
      ln -sf "$EXE" /imgui/example_null; \
    fi

# Default to an interactive shell for inspection
CMD ["/bin/bash"]