import { optFlag, undefList } from "./common";

export type CMakeDefinition = {
    name: string,
    value: string,
    type?: CMakeVariableType;
};

export type CMakeVariableType = "BOOL" | "FILEPATH" | "PATH" | "STRING" | "INTERNAL";

/**
 * General CMake variables.
 */
export interface GeneralVariable {
    CMAKE_BUILD_TYPE?: "Debug" | "Release" | "RelWithDebInfo" | "MinSizeRel";
    BUILD_SHARED_LIBS?: boolean,
    CMAKE_INSTALL_PREFIX?: string,
    CMAKE_SYSROOT?: string,
    CMAKE_C_COMPILER?: string,
    CMAKE_CXX_COMPILER?: string,
    CMAKE_Fortran_COMPILER?: string,
    CMAKE_Fortran_COMPILER_ID?: string,
    CMAKE_C_FLAGS?: string,
    CMAKE_CXX_FLAGS?: string,
}

/**
 * CMake variables suitable for LLVM project.
 */
export interface LLVMVariable {
    LLVM_TARGETS_TO_BUILD?: string[];
    LLVM_ENABLE_CLASSIC_FLANG?: boolean,
    LLVM_ENABLE_PROJECTS?: ("clang" | "openmp" | "lld" | "clang-tools-extra")[];
    LIBOMP_ARCH?: "Sw64";
    LIBOMP_USE_ITT_NOTIFY?: boolean;
    LIBOMP_ENABLE_SHARED?: boolean;
    OPENMP_ENABLE_LIBOMPTARGET?: boolean;
}

export interface CFlangCMakeVariable {
    FLANG_INCLUDE_DIRS?: boolean;
    FLANG_LLVM_EXTENSIONS?: boolean;
    WITH_WERROR?: boolean;
    LLVM_CONFIG?: string;
}

/**
 * Generate cmake definitions, take care of funny cmake string lists.
 *
 * @param object A set of cmake variables to generate
 * @returns A list of cmake definitions, could be passed to CLI
 */
export function variable(object: Object): CMakeDefinition[] {
    return Object.entries(object).map(([k, v]) => {
        if (typeof v === "boolean") {
            return {
                name: k,
                value: v ? "ON" : "OFF",
                type: "BOOL"
            };
        } else if (typeof v === "object" && Array.isArray(v)) {
            return {
                name: k,
                value: v.join(";"),
                type: "STRING"
            };
        } else {
            return {
                name: k,
                value: v,
                type: "STRING"
            };
        }
    }
    );
}


/**
 * Options for "Generate a Project Buildsystem"
 * @see https://cmake.org/cmake/help/latest/manual/cmake.1.html#generate-a-project-buildsystem
 */
export interface CMakeGenerateOptions {
    pathToBuild?: string;
    pathToSource?: string;

    /**
     * Pre-load a script to populate the cache.
     * When CMake is first run in an empty build tree, it creates a
     * CMakeCache.txt file and populates it with customizable settings for the project.
     * This option may be used to specify a file from which to load cache entries
     * before the first pass through the project's CMake listfiles.
     * The loaded entries take priority over the project's default values.
     * The given file should be a CMake script containing set() commands that use the CACHE option,
     * not a cache-format file.
     */
    preloadCache?: string;


    definitions?: CMakeDefinition[];

    /**
     * Specify a build system generator.
     *
     * CMake may support multiple native build systems on certain platforms.
     * A generator is responsible for generating a particular build system.
     * Possible generator names are specified in the [cmake-generators(7)](https://cmake.org/cmake/help/latest/manual/cmake-generators.7.html#manual:cmake-generators(7)) manual.
     */
    generator?: "Unix Makefiles" | "Ninja";

    /**
     * Specify the cross compiling toolchain file, equivalent to setting CMAKE_TOOLCHAIN_FILE variable.
     * Relative paths are interpreted as relative to the build directory,
     * and if not found, relative to the source directory.
     *
     * New in version 3.21.
     */
    toolchain?: string;
}

export function command(o: CMakeGenerateOptions): string[] {
    return [
        ...optFlag("-G", o.generator),
        ...undefList(o.definitions, defs => defs.flatMap(def => [
            "-D",
            `${def.name}${def.type ? `:${def.type}` : ""}=${def.value}`
        ])),
        ...optFlag("-B", o.pathToBuild),
        ...optFlag("-S", o.pathToSource),
        ...optFlag('-C', o.preloadCache),
    ];
}