# - Try to find Graphviz
# Once done this will define
#
#  GRAPHVIZ_FOUND - system has Graphviz
#  GRAPHVIZ_INCLUDE_DIR - the Graphviz include directory
#  GRAPHVIZ_LIBRARY - Link these to use Graphviz
#  GRAPHVIZ_VERSION = The value of PACKAGE_VERSION defined in graphviz_version.h
#  GRAPHVIZ_MAJOR_VERSION = The library major version number
#  GRAPHVIZ_MINOR_VERSION = The library minor version number
#  GRAPHVIZ_PATCH_VERSION = The library patch version number
#  GRAPHVIZ_COMPILE_FLAGS = List of compile flags needed by the GraphViz installation headers
#
# This module reads hints about search locations from the following env or cache variables:
#  GRAPHVIZ_ROOT          - Graphviz installation prefix
#                           (containing bin/, include/, etc.)

# SPDX-FileCopyrightText: 2009, Adrien Bustany, <madcat@mymadcat.com>
# SPDX-FileCopyrightText: 2012 Klarälvdalens Datakonsult AB, a KDAB Group company <info@kdab.com>

# Version computation and some cleanups by Allen Winter <allen.winter@kdab.com>
# Bug fixing for WIN32 by Guillaume Jacquenot <guillaume.jacquenot@gmail.com>

# SPDX-License-Identifier: GPL-3.0-or-later

include(CheckIncludeFiles)
include(CMakePushCheckState)

if(NOT GRAPHVIZ_MIN_VERSION)
    set(GRAPHVIZ_MIN_VERSION "2.00")
endif()

if(GRAPHVIZ_INCLUDE_DIR
   AND GRAPHVIZ_CDT_LIBRARY
   AND (GRAPHVIZ_CGRAPH_LIBRARY OR GRAPHVIZ_GRAPH_LIBRARY)
   AND GRAPHVIZ_PATHPLAN_LIBRARY
)
    set(GRAPHVIZ_FIND_QUIETLY TRUE)
endif()

# TODO: When requiring CMake 3.12 this logic can probably be simplified. Graphviz_ROOT is being handled by CMake itself
#   Also see CMake policy CMP0074
if(GRAPHVIZ_ROOT)
    set(_GRAPHVIZ_ROOT ${GRAPHVIZ_ROOT})
else()
    if(DEFINED GRAPHVIZ_ROOT)
        set(_GRAPHVIZ_ROOT $ENV{GRAPHVIZ_ROOT})
    endif()
endif()

if(NOT _GRAPHVIZ_ROOT)
    if(WIN32)
        message(STATUS "Trying to find a Graphviz installation by looking up the `dot` tool.")
        find_program(DOT_TOOL dot)
        if(DOT_TOOL)
            get_filename_component(_dotPath ${DOT_TOOL} PATH)
            message(STATUS "Found dot tool in ${_dotPath}, checking whether it's in a valid Graphviz install")
            # dot.exe could be installed elsewhere, make sure that's not the case here
            if(EXISTS "${_dotPath}/include")
                message("Found valid Graphviz install: ${dotPath}")
                set(_GRAPHVIZ_ROOT ${dotPath})
            endif()
        endif()
    endif()
endif()

if(_GRAPHVIZ_ROOT)
    set(_GRAPHVIZ_INCLUDE_DIR ${_GRAPHVIZ_ROOT}/include)
    set(_GRAPHVIZ_LIBRARY_DIR ${_GRAPHVIZ_ROOT}/lib)
    set(_GRAPHVIZ_FIND_OPTS NO_DEFAULT_PATH)
else()
    set(_GRAPHVIZ_INCLUDE_DIR "")
    set(_GRAPHVIZ_LIBRARY_DIR "")
    set(_GRAPHVIZ_FIND_OPTS "")
endif()

find_path(
    GRAPHVIZ_INCLUDE_DIR
    NAMES graphviz/graph.h graphviz/cgraph.h
    HINTS ${_GRAPHVIZ_INCLUDE_DIR} ${_GRAPHVIZ_FIND_OPTS}
)

if(WIN32)
    if(CMAKE_BUILD_TYPE STREQUAL "Release")
        set(GRAPHVIZ_LIB_PATH_SUFFIX "release/lib")
    else()
        set(GRAPHVIZ_LIB_PATH_SUFFIX "debug/lib")
    endif()
else()
    set(GRAPHVIZ_LIB_PATH_SUFFIX)
endif()

find_library(
    GRAPHVIZ_CDT_LIBRARY
    NAMES cdt
    HINTS ${_GRAPHVIZ_LIBRARY_DIR}
    PATH_SUFFIXES ${GRAPHVIZ_LIB_PATH_SUFFIX} ${_GRAPHVIZ_FIND_OPTS}
)
find_library(
    GRAPHVIZ_GVC_LIBRARY
    NAMES gvc
    HINTS ${_GRAPHVIZ_LIBRARY_DIR}
    PATH_SUFFIXES ${GRAPHVIZ_LIB_PATH_SUFFIX} ${_GRAPHVIZ_FIND_OPTS}
)
find_library(
    GRAPHVIZ_CGRAPH_LIBRARY
    NAMES cgraph
    HINTS ${_GRAPHVIZ_LIBRARY_DIR}
    PATH_SUFFIXES ${GRAPHVIZ_LIB_PATH_SUFFIX} ${_GRAPHVIZ_FIND_OPTS}
)
find_library(
    GRAPHVIZ_GRAPH_LIBRARY
    NAMES graph
    HINTS ${_GRAPHVIZ_LIBRARY_DIR}
    PATH_SUFFIXES ${GRAPHVIZ_LIB_PATH_SUFFIX} ${_GRAPHVIZ_FIND_OPTS}
)
find_library(
    GRAPHVIZ_PATHPLAN_LIBRARY
    NAMES pathplan
    HINTS ${_GRAPHVIZ_LIBRARY_DIR}
    PATH_SUFFIXES ${GRAPHVIZ_LIB_PATH_SUFFIX} ${_GRAPHVIZ_FIND_OPTS}
)

find_library(
    GRAPHVIZ_PLUGIN_DOT_LAYOUT_LIBRARY
    NAMES gvplugin_dot_layout
    HINTS ${_GRAPHVIZ_LIBRARY_DIR}
    PATH_SUFFIXES ${GRAPHVIZ_LIB_PATH_SUFFIX} ${_GRAPHVIZ_FIND_OPTS} graphviz
)

cmake_push_check_state()
if(NOT DEFINED CMAKE_REQUIRED_INCLUDES)
    set(CMAKE_REQUIRED_INCLUDES "") #to make --warn-uninitialized happy
endif()
set(CMAKE_REQUIRED_INCLUDES ${CMAKE_REQUIRED_INCLUDES} ${GRAPHVIZ_INCLUDE_DIR})
check_include_files(graphviz/graphviz_version.h HAVE_GRAPHVIZ_VERSION_H)
cmake_pop_check_state()

if(GRAPHVIZ_INCLUDE_DIR
   AND GRAPHVIZ_CDT_LIBRARY
   AND GRAPHVIZ_GVC_LIBRARY
   AND (GRAPHVIZ_CGRAPH_LIBRARY OR GRAPHVIZ_GRAPH_LIBRARY)
   AND GRAPHVIZ_PATHPLAN_LIBRARY
)
    if(HAVE_GRAPHVIZ_VERSION_H OR WIN32)
        set(GRAPHVIZ_FOUND TRUE)
    endif()
else()
    set(GRAPHVIZ_FOUND FALSE)
endif()

# Ok, now compute the version and make sure its greater then the min required
if(GRAPHVIZ_FOUND)
    if(NOT WIN32)
        set(FIND_GRAPHVIZ_VERSION_SOURCE
            "#include <graphviz/graphviz_version.h>\n#include <stdio.h>\n int main()\n {\n printf(\"%s\",PACKAGE_VERSION);return 1;\n }\n"
        )
        set(FIND_GRAPHVIZ_VERSION_SOURCE_FILE ${CMAKE_BINARY_DIR}/CMakeTmp/FindGRAPHVIZ.cxx)
        file(WRITE "${FIND_GRAPHVIZ_VERSION_SOURCE_FILE}" "${FIND_GRAPHVIZ_VERSION_SOURCE}")

        set(FIND_GRAPHVIZ_VERSION_ADD_INCLUDES "-DINCLUDE_DIRECTORIES:STRING=${GRAPHVIZ_INCLUDE_DIR}")

        if(NOT CMAKE_CROSSCOMPILING)
            try_run(
                RUN_RESULT COMPILE_RESULT ${CMAKE_BINARY_DIR} ${FIND_GRAPHVIZ_VERSION_SOURCE_FILE}
                CMAKE_FLAGS "${FIND_GRAPHVIZ_VERSION_ADD_INCLUDES}"
                RUN_OUTPUT_VARIABLE GRAPHVIZ_VERSION
            )
        endif()

        if(COMPILE_RESULT
           AND RUN_RESULT EQUAL 1
           AND NOT CMAKE_CROSSCOMPILING
        )
            message(STATUS "Found Graphviz version ${GRAPHVIZ_VERSION}")
            if(GRAPHVIZ_VERSION VERSION_LESS GRAPHVIZ_MIN_VERSION)
                message(
                    STATUS
                        "Graphviz version ${GRAPHVIZ_VERSION} is too old. At least version ${GRAPHVIZ_MIN_VERSION} is needed."
                )
                set(GRAPHVIZ_FOUND FALSE)
                set(GRAPHVIZ_INCLUDE_DIR "")
                set(GRAPHVIZ_CDT_LIBRARY "")
                set(GRAPHVIZ_GVC_LIBRARY "")
                set(GRAPHVIZ_CGRAPH_LIBRARY "")
                set(GRAPHVIZ_GRAPH_LIBRARY "")
                set(GRAPHVIZ_PATHPLAN_LIBRARY "")
            else()
                # Compute the major and minor version numbers
                if(NOT CMAKE_CROSSCOMPILING)
                    string(REPLACE "." ";" VL ${GRAPHVIZ_VERSION})
                    list(GET VL 0 GRAPHVIZ_MAJOR_VERSION)
                    list(GET VL 1 GRAPHVIZ_MINOR_VERSION)
                    list(GET VL 2 GRAPHVIZ_PATCH_VERSION)
                endif()
            endif()
        else()
            if(NOT CMAKE_CROSSCOMPILING)
                message(FATAL_ERROR "Unable to compile or run the graphviz version detection program.")
            endif()
        endif()
    elseif()
        find_program(DOT_TOOL dot PATHS ${_GRAPHVIZ_ROOT}/bin)
        execute_process(
            COMMAND ${DOT_TOOL} -V
            OUTPUT_VARIABLE DOT_VERSION_OUTPUT
            ERROR_VARIABLE DOT_VERSION_OUTPUT
        )
        string(REGEX MATCH "([0-9]+\\.[0-9]+\\.[0-9]+)" GRAPHVIZ_VERSION "${DOT_VERSION_OUTPUT}")
        string(REPLACE "." ";" VL ${GRAPHVIZ_VERSION})
        list(GET VL 0 GRAPHVIZ_MAJOR_VERSION)
        list(GET VL 1 GRAPHVIZ_MINOR_VERSION)
        list(GET VL 2 GRAPHVIZ_PATCH_VERSION)
    endif()

    set(GRAPHVIZ_COMPILE_FLAGS "")
    check_include_files(string.h HAVE_STRING_H)
    if(HAVE_STRING_H)
        list(APPEND GRAPHVIZ_COMPILE_FLAGS "-DHAVE_STRING_H=1")
    endif()

    if(NOT GRAPHVIZ_FIND_QUIETLY)
        message(
            STATUS
                "Found Graphviz: ${GRAPHVIZ_CDT_LIBRARY} ${GRAPHVIZ_GVC_LIBRARY} ${GRAPHVIZ_CGRAPH_LIBRARY} ${GRAPHVIZ_GRAPH_LIBRARY} ${GRAPHVIZ_PATHPLAN_LIBRARY}"
        )
    endif()
else()
    if(GRAPHVIZ_FIND_REQUIRED)
        message(FATAL_ERROR "Could NOT find Graphivz")
    endif()
endif()