#!/usr/bin/env bash
#
# SPDX-License-Identifier: GPL-2.0
#
# Copyright (c) 2026 AMLOGIC
#
# Linux UAPI headers build script for AMLbian
# This script installs Linux UAPI headers for different Amlogic chipsets

set -e

# Get script directory
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
AMLBIAN_DIR="$(dirname "${SCRIPT_DIR}")"
BUILD_DIR="${AMLBIAN_DIR}/../build"

# Source common functions
if [[ -f "${AMLBIAN_DIR}/lib/function-common.sh" ]]; then
    source "${AMLBIAN_DIR}/lib/function-common.sh"
fi

# ==============================================================================
# Section 2: Default Configuration
# ==============================================================================

KERNEL_VERSION="${KERNEL_VERSION:-6.12}"
BOARD="${BOARD:-s6-bq201}"
DEB_VERSION="1.0"

# ==============================================================================
# Section 4: Linux UAPI Headers Build Functions
# ==============================================================================

function __linux_uapi_headers_prepare_source {
    local build_dir="${1}"

    local aml_comp_path="$(amlbian_get_aml_comp_dir)"
    if [[ -z "${aml_comp_path}" ]] || [[ ! -d "${aml_comp_path}" ]]; then
        display_alert "LINUX-UAPI-HEADERS" "aml-comp not found: ${aml_comp_path}" "err"
        exit 1
    fi
    
    # 查找内核构建目录
    local kernel_build_dir="${aml_comp_path}/kernel/aml-${KERNEL_VERSION}/build"
    local STAGING_KERNEL_DIR="${aml_comp_path}/kernel/aml-${KERNEL_VERSION}"
    
    if [[ ! -d "${kernel_build_dir}" ]]; then
        display_alert "LINUX-UAPI-HEADERS" "Kernel build directory not found. Expected at: ${kernel_build_dir}" "err"
        return 1
    fi
    
    display_alert "LINUX-UAPI-HEADERS" "Source prepared successfully" "success"
    return 0
}

function __linux_uapi_headers_install {
    local install_dir="${1}"
    
    display_alert "LINUX-UAPI-HEADERS" "Starting Linux UAPI headers installation..." "info"
    
    local aml_comp_path="$(amlbian_get_aml_comp_dir)"
    if [[ -z "${aml_comp_path}" ]] || [[ ! -d "${aml_comp_path}" ]]; then
        display_alert "LINUX-UAPI-HEADERS" "aml-comp not found: ${aml_comp_path}" "err"
        exit 1
    fi
    
    local STAGING_KERNEL_DIR="${aml_comp_path}/kernel/aml-${KERNEL_VERSION}"
    
    if [[ ! -d "${STAGING_KERNEL_DIR}" ]]; then
        display_alert "LINUX-UAPI-HEADERS" "Kernel source directory not found: ${STAGING_KERNEL_DIR}" "err"
        return 1
    fi
    
    local includedir="${install_dir}/usr/include"
    mkdir -p "${includedir}/linux/amlogic"
    
    # 1. 安装 Amlogic 自定义头文件（有第二种路径尝试）
    display_alert "LINUX-UAPI-HEADERS" "Installing Amlogic customized headers..." "info"
    
    local aml_uapi_path="${STAGING_KERNEL_DIR}/common_drivers/include/uapi/amlogic"
    
    if [[ -d "${aml_uapi_path}" ]]; then
        cp -af "${aml_uapi_path}" "${includedir}/linux/"
        display_alert "LINUX-UAPI-HEADERS" "Copied Amlogic headers from ${aml_uapi_path}" "info"
    else
        display_alert "LINUX-UAPI-HEADERS" "Amlogic headers not found at both locations" "warn"
    fi
    
    # 2. 安装额外头文件 (dma-heap.h, ion.h)
    display_alert "LINUX-UAPI-HEADERS" "Installing extra headers..." "info"
    
    local uapi_path="${STAGING_KERNEL_DIR}/include/uapi/linux/"
    
    for f in dma-heap.h ion.h; do
        if [[ -f "${uapi_path}${f}" ]]; then
            # 简化处理：只检查目标目录是否已存在
            if [[ ! -e "${includedir}/linux/${f}" ]]; then
                install -m 0644 "${uapi_path}${f}" "${includedir}/linux/"
                display_alert "LINUX-UAPI-HEADERS" "Installed ${f}" "info"
            else
                display_alert "LINUX-UAPI-HEADERS" "Skipping ${f} - already exists" "info"
            fi
        else
            display_alert "LINUX-UAPI-HEADERS" "Header ${f} not found at ${uapi_path}" "debug"
        fi
    done
    
    # 3. 安装 DVB 额外头文件
    display_alert "LINUX-UAPI-HEADERS" "Installing DVB extra headers..." "info"
    
    for f in aml_ca_ext.h aml_dmx_ext.h aml_fe_ext.h; do
        if [[ -f "${uapi_path}/dvb/${f}" ]]; then
            install -m 0644 "${uapi_path}/dvb/${f}" "${includedir}/linux/amlogic/"
            display_alert "LINUX-UAPI-HEADERS" "Installed DVB header ${f}" "info"
        else
            display_alert "LINUX-UAPI-HEADERS" "DVB header ${f} not found" "debug"
        fi
    done
    
    display_alert "LINUX-UAPI-HEADERS" "Installation completed" "success"
    return 0
}

function __linux_uapi_headers_create_deb {
    local build_dir="${1}"
    local install_dir="${2}"
    
    # 设置必要的变量
    local pkg_name="linux-uapi-headers"
    local version="${DEB_VERSION}"
    local architecture="${ARCH:-arm64}"
    local maintainer="Amlbian Builder <build@amlbian.com>"
    local description="Linux UAPI headers for kernel ${KERNEL_VERSION}"
    
    display_alert "LINUX-UAPI-HEADERS" "Creating Debian package for ${pkg_name} ${version}..." "info"
    
    # 创建Debian包控制文件
    local deb_dir="${build_dir}/deb/${pkg_name}-${version}"
    local debian_dir="${deb_dir}/DEBIAN"
    
    mkdir -p "${debian_dir}"

    # 将安装目录的内容复制到debian-root
    if [[ -d "${install_dir}" ]] && [[ "$(ls -A "${install_dir}")" ]]; then
        cp -r "${install_dir}"/* "${deb_dir}/" 2>/dev/null || true
        display_alert "LINUX-UAPI-HEADERS" "Copied installed files to ${deb_dir}" "info"
    else
        display_alert "LINUX-UAPI-HEADERS" "No installed files found in ${install_dir}" "warn"
        return 0
    fi

    # 创建control文件
    cat > "${debian_dir}/control" <<EOF
Package: ${pkg_name}
Version: ${version}
Architecture: ${architecture}
Maintainer: ${maintainer}
Description: ${description}
 This package provides Linux UAPI headers for Amlogic hardware.
Section: devel
Priority: optional
EOF
    
    display_alert "LINUX-UAPI-HEADERS" "Building Debian package..." "info"
    
    # 构建Debian包
    cd "${build_dir}/deb"
    dpkg-deb --build "${pkg_name}-${version}"
    
    local deb_file="${pkg_name}-${version}.deb"
    if [[ -f "${deb_file}" ]]; then
        local output_dir="${BUILD_DIR}/output"
        mkdir -p "${output_dir}"
        mv "${deb_file}" "${output_dir}/linux-${pkg_name}-${BOARD}-amlbian_${version}_${architecture}.deb"
        display_alert "LINUX-UAPI-HEADERS" "Debian package created: ${output_dir}/linux-${pkg_name}-${BOARD}-amlbian_${version}_${architecture}.deb" "success"
    else
        display_alert "LINUX-UAPI-HEADERS" "Failed to build Debian package" "err"
        return 1
    fi
    
    return 0
}

function amlbian_build_linux_uapi_headers {
    if ! is_unit_enabled "linux-uapi-headers"; then
        display_alert "[SKIP] >> linux-uapi-headers disable in BUILD_UNITS" "" "info"
        return
    fi

    display_alert "AMLOGIC: Building Linux UAPI headers ${KERNEL_VERSION} ${BOARD}" "info"
    
    # Define all directory paths (in .tmp directory)
    local build_root="${BUILD_DIR}/.tmp/linux-uapi-headers-build-${ARCH:-arm64}"
    local build_dir="${build_root}/build"        # Build directory
    local install_dir="${build_root}/install"    # Install directory

    rm -rf "${build_root}" 

    # 创建目录
    mkdir -p "${build_dir}" "${install_dir}"

    display_alert "AMLOGIC: build_dir  ${build_dir}" "info"
    display_alert "AMLOGIC: install_dir  ${install_dir}" "info"
    display_alert "AMLOGIC: output_dir  ${BUILD_DIR}/output" "info"

    # 准备源代码
    __linux_uapi_headers_prepare_source "${build_dir}"
    
    # 安装头文件
    if ! __linux_uapi_headers_install "${install_dir}"; then
        display_alert "AMLOGIC: Linux UAPI headers installation failed" "err"
        return 1
    fi

    display_alert "AMLOGIC: Creating Debian package..." "info"
    __linux_uapi_headers_create_deb "${build_dir}" "${install_dir}"

    return 0
}

# ==============================================================================
# Section 5: Main
# ==============================================================================

display_alert "AMLIbian Linux UAPI Headers Build Script" "Version: ${KERNEL_VERSION}, Board: ${BOARD}" "info"

amlbian_build_linux_uapi_headers

display_alert "AMLOGIC: Linux UAPI headers build completed" "${OUTPUT_DIR}" "info"

# ==============================================================================
# End of build-linux-uapi-headers.sh
# ==============================================================================