# Copyright (c) 2013-2017, Ruslan Baratov
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice, this
#   list of conditions and the following disclaimer.
#
# * Redistributions in binary form must reproduce the above copyright notice,
#   this list of conditions and the following disclaimer in the documentation
#   and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

# This is a gate file to Hunter package manager.
# Include this file using `include` command and add package you need, example:
#
#     cmake_minimum_required(VERSION 3.0)
#
#     include("cmake/HunterGate.cmake")
#     HunterGate(
#         URL "https://github.com/path/to/hunter/archive.tar.gz"
#         SHA1 "798501e983f14b28b10cda16afa4de69eee1da1d"
#     )
#
#     project(MyProject)
#
#     hunter_add_package(Foo)
#     hunter_add_package(Boo COMPONENTS Bar Baz)
#
# Projects:
#     * https://github.com/hunter-packages/gate/
#     * https://github.com/ruslo/hunter

option(HUNTER_ENABLED "Enable Hunter package manager support" ON)
if(HUNTER_ENABLED)
    if(CMAKE_VERSION VERSION_LESS "3.0")
        message(FATAL_ERROR "At least CMake version 3.0 required for hunter dependency management."
            " Update CMake or set HUNTER_ENABLED to OFF.")
    endif()
endif()

include(CMakeParseArguments) # cmake_parse_arguments

option(HUNTER_STATUS_PRINT "Print working status" ON)
option(HUNTER_STATUS_DEBUG "Print a lot info" OFF)

set(HUNTER_WIKI "https://github.com/ruslo/hunter/wiki")

function(hunter_gate_status_print)
    foreach(print_message ${ARGV})
        if(HUNTER_STATUS_PRINT OR HUNTER_STATUS_DEBUG)
            message(STATUS "[hunter] ${print_message}")
        endif()
    endforeach()
endfunction()

function(hunter_gate_status_debug)
    foreach(print_message ${ARGV})
        if(HUNTER_STATUS_DEBUG)
            string(TIMESTAMP timestamp)
            message(STATUS "[hunter *** DEBUG *** ${timestamp}] ${print_message}")
        endif()
    endforeach()
endfunction()

function(hunter_gate_wiki wiki_page)
    message("------------------------------ WIKI -------------------------------")
    message("    ${HUNTER_WIKI}/${wiki_page}")
    message("-------------------------------------------------------------------")
    message("")
    message(FATAL_ERROR "")
endfunction()

function(hunter_gate_internal_error)
    message("")
    foreach(print_message ${ARGV})
        message("[hunter ** INTERNAL **] ${print_message}")
    endforeach()
    message("[hunter ** INTERNAL **] [Directory:${CMAKE_CURRENT_LIST_DIR}]")
    message("")
    hunter_gate_wiki("error.internal")
endfunction()

function(hunter_gate_fatal_error)
    cmake_parse_arguments(hunter "" "WIKI" "" "${ARGV}")
    string(COMPARE EQUAL "${hunter_WIKI}" "" have_no_wiki)
    if(have_no_wiki)
        hunter_gate_internal_error("Expected wiki")
    endif()
    message("")
    foreach(x ${hunter_UNPARSED_ARGUMENTS})
        message("[hunter ** FATAL ERROR **] ${x}")
    endforeach()
    message("[hunter ** FATAL ERROR **] [Directory:${CMAKE_CURRENT_LIST_DIR}]")
    message("")
    hunter_gate_wiki("${hunter_WIKI}")
endfunction()

function(hunter_gate_user_error)
    hunter_gate_fatal_error(${ARGV} WIKI "error.incorrect.input.data")
endfunction()

function(hunter_gate_self root version sha1 result)
    string(COMPARE EQUAL "${root}" "" is_bad)
    if(is_bad)
        hunter_gate_internal_error("root is empty")
    endif()

    string(COMPARE EQUAL "${version}" "" is_bad)
    if(is_bad)
        hunter_gate_internal_error("version is empty")
    endif()

    string(COMPARE EQUAL "${sha1}" "" is_bad)
    if(is_bad)
        hunter_gate_internal_error("sha1 is empty")
    endif()

    string(SUBSTRING "${sha1}" 0 7 archive_id)

    if(EXISTS "${root}/cmake/Hunter")
        set(hunter_self "${root}")
    else()
        set(
            hunter_self
            "${root}/_Base/Download/Hunter/${version}/${archive_id}/Unpacked"
        )
    endif()

    set("${result}" "${hunter_self}" PARENT_SCOPE)
endfunction()

# Set HUNTER_GATE_ROOT cmake variable to suitable value.
function(hunter_gate_detect_root)
    # Check CMake variable
    string(COMPARE NOTEQUAL "${HUNTER_ROOT}" "" not_empty)
    if(not_empty)
        set(HUNTER_GATE_ROOT "${HUNTER_ROOT}" PARENT_SCOPE)
        hunter_gate_status_debug("HUNTER_ROOT detected by cmake variable")
        return()
    endif()

    # Check environment variable
    string(COMPARE NOTEQUAL "$ENV{HUNTER_ROOT}" "" not_empty)
    if(not_empty)
        set(HUNTER_GATE_ROOT "$ENV{HUNTER_ROOT}" PARENT_SCOPE)
        hunter_gate_status_debug("HUNTER_ROOT detected by environment variable")
        return()
    endif()

    # Check HOME environment variable
    string(COMPARE NOTEQUAL "$ENV{HOME}" "" result)
    if(result)
        set(HUNTER_GATE_ROOT "$ENV{HOME}/.hunter" PARENT_SCOPE)
        hunter_gate_status_debug("HUNTER_ROOT set using HOME environment variable")
        return()
    endif()

    # Check SYSTEMDRIVE and USERPROFILE environment variable (windows only)
    if(WIN32)
        string(COMPARE NOTEQUAL "$ENV{SYSTEMDRIVE}" "" result)
        if(result)
            set(HUNTER_GATE_ROOT "$ENV{SYSTEMDRIVE}/.hunter" PARENT_SCOPE)
            hunter_gate_status_debug(
                "HUNTER_ROOT set using SYSTEMDRIVE environment variable"
            )
            return()
        endif()

        string(COMPARE NOTEQUAL "$ENV{USERPROFILE}" "" result)
        if(result)
            set(HUNTER_GATE_ROOT "$ENV{USERPROFILE}/.hunter" PARENT_SCOPE)
            hunter_gate_status_debug(
                "HUNTER_ROOT set using USERPROFILE environment variable"
            )
            return()
        endif()
    endif()

    hunter_gate_fatal_error(
        "Can't detect HUNTER_ROOT"
        WIKI "error.detect.hunter.root"
    )
endfunction()

macro(hunter_gate_lock dir)
    if(NOT HUNTER_SKIP_LOCK)
        if("${CMAKE_VERSION}" VERSION_LESS "3.2")
            hunter_gate_fatal_error(
                "Can't lock, upgrade to CMake 3.2 or use HUNTER_SKIP_LOCK"
                WIKI "error.can.not.lock"
            )
        endif()
        hunter_gate_status_debug("Locking directory: ${dir}")
        file(LOCK "${dir}" DIRECTORY GUARD FUNCTION)
        hunter_gate_status_debug("Lock done")
    endif()
endmacro()

function(hunter_gate_download dir)
    string(
        COMPARE
        NOTEQUAL
        "$ENV{HUNTER_DISABLE_AUTOINSTALL}"
        ""
        disable_autoinstall
    )
    if(disable_autoinstall AND NOT HUNTER_RUN_INSTALL)
        hunter_gate_fatal_error(
            "Hunter not found in '${dir}'"
            "Set HUNTER_RUN_INSTALL=ON to auto-install it from '${HUNTER_GATE_URL}'"
            "Settings:"
            "  HUNTER_ROOT: ${HUNTER_GATE_ROOT}"
            "  HUNTER_SHA1: ${HUNTER_GATE_SHA1}"
            WIKI "error.run.install"
        )
    endif()
    string(COMPARE EQUAL "${dir}" "" is_bad)
    if(is_bad)
        hunter_gate_internal_error("Empty 'dir' argument")
    endif()

    string(COMPARE EQUAL "${HUNTER_GATE_SHA1}" "" is_bad)
    if(is_bad)
        hunter_gate_internal_error("HUNTER_GATE_SHA1 empty")
    endif()

    string(COMPARE EQUAL "${HUNTER_GATE_URL}" "" is_bad)
    if(is_bad)
        hunter_gate_internal_error("HUNTER_GATE_URL empty")
    endif()

    set(done_location "${dir}/DONE")
    set(sha1_location "${dir}/SHA1")

    set(build_dir "${dir}/Build")
    set(cmakelists "${dir}/CMakeLists.txt")

    hunter_gate_lock("${dir}")
    if(EXISTS "${done_location}")
        # while waiting for lock other instance can do all the job
        hunter_gate_status_debug("File '${done_location}' found, skip install")
        return()
    endif()

    file(REMOVE_RECURSE "${build_dir}")
    file(REMOVE_RECURSE "${cmakelists}")

    file(MAKE_DIRECTORY "${build_dir}") # check directory permissions

    # Disabling languages speeds up a little bit, reduces noise in the output
    # and avoids path too long windows error
    file(
        WRITE
        "${cmakelists}"
        "cmake_minimum_required(VERSION 3.0)\n"
        "project(HunterDownload LANGUAGES NONE)\n"
        "include(ExternalProject)\n"
        "ExternalProject_Add(\n"
        "    Hunter\n"
        "    URL\n"
        "    \"${HUNTER_GATE_URL}\"\n"
        "    URL_HASH\n"
        "    SHA1=${HUNTER_GATE_SHA1}\n"
        "    DOWNLOAD_DIR\n"
        "    \"${dir}\"\n"
        "    SOURCE_DIR\n"
        "    \"${dir}/Unpacked\"\n"
        "    CONFIGURE_COMMAND\n"
        "    \"\"\n"
        "    BUILD_COMMAND\n"
        "    \"\"\n"
        "    INSTALL_COMMAND\n"
        "    \"\"\n"
        ")\n"
    )

    if(HUNTER_STATUS_DEBUG)
        set(logging_params "")
    else()
        set(logging_params OUTPUT_QUIET)
    endif()

    hunter_gate_status_debug("Run generate")

    # Need to add toolchain file too.
    # Otherwise on Visual Studio + MDD this will fail with error:
    # "Could not find an appropriate version of the Windows 10 SDK installed on this machine"
    if(EXISTS "${CMAKE_TOOLCHAIN_FILE}")
        set(toolchain_arg "-DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE}")
    else()
        # 'toolchain_arg' can't be empty
        set(toolchain_arg "-DCMAKE_TOOLCHAIN_FILE=")
    endif()

    string(COMPARE EQUAL "${CMAKE_MAKE_PROGRAM}" "" no_make)
    if(no_make)
        set(make_arg "")
    else()
        # Test case: remove Ninja from PATH but set it via CMAKE_MAKE_PROGRAM
        set(make_arg "-DCMAKE_MAKE_PROGRAM=${CMAKE_MAKE_PROGRAM}")
    endif()

    execute_process(
        COMMAND
        "${CMAKE_COMMAND}"
        "-H${dir}"
        "-B${build_dir}"
        "-G${CMAKE_GENERATOR}"
        "${toolchain_arg}"
        ${make_arg}
        WORKING_DIRECTORY "${dir}"
        RESULT_VARIABLE download_result
        ${logging_params}
    )

    if(NOT download_result EQUAL 0)
        hunter_gate_internal_error("Configure project failed")
    endif()

    hunter_gate_status_print(
        "Initializing Hunter workspace (${HUNTER_GATE_SHA1})"
        "  ${HUNTER_GATE_URL}"
        "  -> ${dir}"
    )
    execute_process(
        COMMAND "${CMAKE_COMMAND}" --build "${build_dir}"
        WORKING_DIRECTORY "${dir}"
        RESULT_VARIABLE download_result
        ${logging_params}
    )

    if(NOT download_result EQUAL 0)
        hunter_gate_internal_error("Build project failed")
    endif()

    file(REMOVE_RECURSE "${build_dir}")
    file(REMOVE_RECURSE "${cmakelists}")

    file(WRITE "${sha1_location}" "${HUNTER_GATE_SHA1}")
    file(WRITE "${done_location}" "DONE")

    hunter_gate_status_debug("Finished")
endfunction()

# Must be a macro so master file 'cmake/Hunter' can
# apply all variables easily just by 'include' command
# (otherwise PARENT_SCOPE magic needed)
macro(HunterGate)
    if(HUNTER_GATE_DONE)
        # variable HUNTER_GATE_DONE set explicitly for external project
        # (see `hunter_download`)
        set_property(GLOBAL PROPERTY HUNTER_GATE_DONE YES)
    endif()

    # First HunterGate command will init Hunter, others will be ignored
    get_property(_hunter_gate_done GLOBAL PROPERTY HUNTER_GATE_DONE SET)

    if(NOT HUNTER_ENABLED)
        # Empty function to avoid error "unknown function"
        function(hunter_add_package)
        endfunction()
    elseif(_hunter_gate_done)
        hunter_gate_status_debug("Secondary HunterGate (use old settings)")
        hunter_gate_self(
            "${HUNTER_CACHED_ROOT}"
            "${HUNTER_VERSION}"
            "${HUNTER_SHA1}"
            _hunter_self
        )
        include("${_hunter_self}/cmake/Hunter")
    else()
        set(HUNTER_GATE_LOCATION "${CMAKE_CURRENT_LIST_DIR}")

        string(COMPARE NOTEQUAL "${PROJECT_NAME}" "" _have_project_name)
        if(_have_project_name)
            hunter_gate_fatal_error(
                "Please set HunterGate *before* 'project' command. "
                "Detected project: ${PROJECT_NAME}"
                WIKI "error.huntergate.before.project"
            )
        endif()

        cmake_parse_arguments(
            HUNTER_GATE "LOCAL" "URL;SHA1;GLOBAL;FILEPATH" "" ${ARGV}
        )

        string(COMPARE EQUAL "${HUNTER_GATE_SHA1}" "" _empty_sha1)
        string(COMPARE EQUAL "${HUNTER_GATE_URL}" "" _empty_url)
        string(
            COMPARE
            NOTEQUAL
            "${HUNTER_GATE_UNPARSED_ARGUMENTS}"
            ""
            _have_unparsed
        )
        string(COMPARE NOTEQUAL "${HUNTER_GATE_GLOBAL}" "" _have_global)
        string(COMPARE NOTEQUAL "${HUNTER_GATE_FILEPATH}" "" _have_filepath)

        if(_have_unparsed)
            hunter_gate_user_error(
                "HunterGate unparsed arguments: ${HUNTER_GATE_UNPARSED_ARGUMENTS}"
            )
        endif()
        if(_empty_sha1)
            hunter_gate_user_error("SHA1 suboption of HunterGate is mandatory")
        endif()
        if(_empty_url)
            hunter_gate_user_error("URL suboption of HunterGate is mandatory")
        endif()
        if(_have_global)
            if(HUNTER_GATE_LOCAL)
                hunter_gate_user_error("Unexpected LOCAL (already has GLOBAL)")
            endif()
            if(_have_filepath)
                hunter_gate_user_error("Unexpected FILEPATH (already has GLOBAL)")
            endif()
        endif()
        if(HUNTER_GATE_LOCAL)
            if(_have_global)
                hunter_gate_user_error("Unexpected GLOBAL (already has LOCAL)")
            endif()
            if(_have_filepath)
                hunter_gate_user_error("Unexpected FILEPATH (already has LOCAL)")
            endif()
        endif()
        if(_have_filepath)
            if(_have_global)
                hunter_gate_user_error("Unexpected GLOBAL (already has FILEPATH)")
            endif()
            if(HUNTER_GATE_LOCAL)
                hunter_gate_user_error("Unexpected LOCAL (already has FILEPATH)")
            endif()
        endif()

        hunter_gate_detect_root() # set HUNTER_GATE_ROOT

        # Beautify path, fix probable problems with windows path slashes
        get_filename_component(
            HUNTER_GATE_ROOT "${HUNTER_GATE_ROOT}" ABSOLUTE
        )
        hunter_gate_status_debug("HUNTER_ROOT: ${HUNTER_GATE_ROOT}")
        if(NOT HUNTER_ALLOW_SPACES_IN_PATH)
            string(FIND "${HUNTER_GATE_ROOT}" " " _contain_spaces)
            if(NOT _contain_spaces EQUAL -1)
                hunter_gate_fatal_error(
                    "HUNTER_ROOT (${HUNTER_GATE_ROOT}) contains spaces."
                    "Set HUNTER_ALLOW_SPACES_IN_PATH=ON to skip this error"
                    "(Use at your own risk!)"
                    WIKI "error.spaces.in.hunter.root"
                )
            endif()
        endif()

        string(
            REGEX
            MATCH
            "[0-9]+\\.[0-9]+\\.[0-9]+[-_a-z0-9]*"
            HUNTER_GATE_VERSION
            "${HUNTER_GATE_URL}"
        )
        string(COMPARE EQUAL "${HUNTER_GATE_VERSION}" "" _is_empty)
        if(_is_empty)
            set(HUNTER_GATE_VERSION "unknown")
        endif()

        hunter_gate_self(
            "${HUNTER_GATE_ROOT}"
            "${HUNTER_GATE_VERSION}"
            "${HUNTER_GATE_SHA1}"
            _hunter_self
        )

        set(_master_location "${_hunter_self}/cmake/Hunter")
        if(EXISTS "${HUNTER_GATE_ROOT}/cmake/Hunter")
            # Hunter downloaded manually (e.g. by 'git clone')
            set(_unused "xxxxxxxxxx")
            set(HUNTER_GATE_SHA1 "${_unused}")
            set(HUNTER_GATE_VERSION "${_unused}")
        else()
            get_filename_component(_archive_id_location "${_hunter_self}/.." ABSOLUTE)
            set(_done_location "${_archive_id_location}/DONE")
            set(_sha1_location "${_archive_id_location}/SHA1")

            # Check Hunter already downloaded by HunterGate
            if(NOT EXISTS "${_done_location}")
                hunter_gate_download("${_archive_id_location}")
            endif()

            if(NOT EXISTS "${_done_location}")
                hunter_gate_internal_error("hunter_gate_download failed")
            endif()

            if(NOT EXISTS "${_sha1_location}")
                hunter_gate_internal_error("${_sha1_location} not found")
            endif()
            file(READ "${_sha1_location}" _sha1_value)
            string(COMPARE EQUAL "${_sha1_value}" "${HUNTER_GATE_SHA1}" _is_equal)
            if(NOT _is_equal)
                hunter_gate_internal_error(
                    "Short SHA1 collision:"
                    "  ${_sha1_value} (from ${_sha1_location})"
                    "  ${HUNTER_GATE_SHA1} (HunterGate)"
                )
            endif()
            if(NOT EXISTS "${_master_location}")
                hunter_gate_user_error(
                    "Master file not found:"
                    "  ${_master_location}"
                    "try to update Hunter/HunterGate"
                )
            endif()
        endif()
        include("${_master_location}")
        set_property(GLOBAL PROPERTY HUNTER_GATE_DONE YES)
    endif()
endmacro()