# Use Ubuntu 18.04 as the base image
FROM ubuntu:18.04

# Update the package list and install basic development tools
RUN apt-get update && \
    apt-get install -y --no-install-recommends \
        build-essential \
        software-properties-common \
        wget \
        curl \
        git \
        unzip

# Download and install CMake
ARG CMAKE_URL="https://github.com/Kitware/CMake/releases/download/v3.17.0-rc3/cmake-3.17.0-rc3-Linux-x86_64.sh"
RUN mkdir /opt/cmake && \
    wget -qO /opt/cmake/install-cmake.sh ${CMAKE_URL} && \
    chmod +x /opt/cmake/install-cmake.sh && \
    /opt/cmake/install-cmake.sh --skip-license --prefix=/usr/local && \
    rm /opt/cmake/install-cmake.sh

# Set the URL for the Android NDK and OpenCV Android SDK
ARG ANDROID_NDK_URL="https://dl.google.com/android/repository/android-ndk-r18b-linux-x86_64.zip"
ARG OPENCV_URL="https://github.com/opencv/opencv/releases/download/4.5.1/opencv-4.5.1-android-sdk.zip"

# Set the installation path for the Android NDK and OpenCV Android SDK
ARG ANDROID_NDK_PATH="/opt/android-ndk-r18b"
ARG OPENCV_PATH="/opt/opencv-android-sdk"

# Download and extract the Android NDK
RUN mkdir -p ${ANDROID_NDK_PATH} && \
    wget -qO /tmp/android-ndk.zip ${ANDROID_NDK_URL} && \
    unzip /tmp/android-ndk.zip -d /opt && \
    rm /tmp/android-ndk.zip

# Set environment variable to point to the NDK directory
ENV ANDROID_NDK=${ANDROID_NDK_PATH}

# Download and extract the OpenCV Android SDK
RUN mkdir -p ${OPENCV_PATH} && \
    wget -qO /tmp/opencv-android-sdk.zip ${OPENCV_URL} && \
    unzip /tmp/opencv-android-sdk.zip -d ${OPENCV_PATH} && \
    rm /tmp/opencv-android-sdk.zip

# Set environment variable to point to the OpenCV SDK directory
ENV OPENCV_DIR=${OPENCV_PATH}/OpenCV-android-sdk/sdk/native/jni

# Clean temporary files to reduce image size
RUN apt-get clean && \
    rm -rf /var/lib/apt/lists/*

# Set the working directory
WORKDIR /workspace

# Default to running Bash
CMD ["/bin/bash"]