# ======================================================================================================================
#  fennec, a free and open source game engine
#  Copyright © 2025  Medusa Slockbower
#
#  This program is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program.  If not, see <https://www.gnu.org/licenses/>.
# ======================================================================================================================

# https://gist.github.com/mariobadr/acc3c8adf4b4e722705be38c3deac59a
# this script finds libwayland and dependencies

# some of this code is based on SDL3's use of wayland-scanner

macro(fennec_wayland_get_header _SCANNER _XML _FILE)
    set(_WAYLAND_PROT_H_CODE "${WAYLAND_HEADERS_DIR}/${_FILE}-client-protocols.h")
    set(_WAYLAND_PROT_C_CODE "${WAYLAND_SOURCES_DIR}/${_FILE}-client.c")

    execute_process(
            COMMAND ${_SCANNER} client-header "${_XML}" "${_WAYLAND_PROT_H_CODE}"
    )

    execute_process(
            COMMAND ${_SCANNER} private-code "${_XML}" "${_WAYLAND_PROT_C_CODE}"
    )

    fennec_add_sources(${_WAYLAND_PROT_C_CODE} ${_WAYLAND_PROT_H_CODE})
endmacro()

macro(fennec_check_wayland)
    set(WAYLAND_CLIENT_FOUND 0)

    find_path(
            WAYLAND_CLIENT_INCLUDE_DIR
            NAMES wayland-client.h
    )
    find_library(
            WAYLAND_CLIENT_LIBRARY
            NAMES wayland-client libwayland-client
    )
    find_program(WAYLAND_SCANNER NAMES wayland-scanner)

    # EGL is required
    find_path(
            WAYLAND_EGL_INCLUDE_DIR
            NAMES wayland-egl.h
    )
    find_library(
            WAYLAND_EGL_LIBRARY
            NAMES wayland-egl libwayland-egl
    )

    if( (WAYLAND_CLIENT_INCLUDE_DIR AND WAYLAND_CLIENT_LIBRARY AND WAYLAND_SCANNER)
            AND (WAYLAND_EGL_INCLUDE_DIR AND WAYLAND_EGL_LIBRARY))
        message(STATUS "Found Wayland: ${WAYLAND_CLIENT_LIBRARY}")

        set(WAYLAND_PROTOCOLS_DIR ${FENNEC_SOURCE_DIR}/include/fennec/platform/linux/wayland/lib/protocols)
        set(WAYLAND_HEADERS_DIR ${FENNEC_SOURCE_DIR}/include/fennec/platform/linux/wayland/lib/headers)
        set(WAYLAND_SOURCES_DIR ${FENNEC_SOURCE_DIR}/source/platform/linux/wayland/lib/sources)

        # Search for base protocol xml
        find_file(WAYLAND_PROTOCOL NAMES wayland.xml PATHS /usr/share/wayland /usr/share/wayland-protocols)
        file(COPY ${WAYLAND_PROTOCOL} DESTINATION ${WAYLAND_PROTOCOLS_DIR})

        # search for xdg protocols
        find_file(XDG_SHELL_PROTOCOL NAMES xdg-shell.xml PATHS /usr/share/wayland-protocols/stable/xdg-shell)
        file(COPY ${XDG_SHELL_PROTOCOL} DESTINATION ${WAYLAND_PROTOCOLS_DIR})

        # include sub-dependencies
        include("${FENNEC_SOURCE_DIR}/cmake/xkb.cmake")
        fennec_check_xkb()

        # generate protocols, based on SDL3
        file(GLOB WAYLAND_PROTOCOLS_XML RELATIVE "${WAYLAND_PROTOCOLS_DIR}" "${WAYLAND_PROTOCOLS_DIR}/*.xml")
        foreach(_XML IN LISTS WAYLAND_PROTOCOLS_XML)
            get_filename_component(_FILE ${_XML} NAME_WLE)
            fennec_wayland_get_header("${WAYLAND_SCANNER}" "${WAYLAND_PROTOCOLS_DIR}/${_XML}" "${_FILE}")
        endforeach()

        # Add sources and libraries
        get_filename_component(
                WAYLAND_CLIENT_LIBRARY
                ${WAYLAND_CLIENT_LIBRARY}
                NAME
        )
        get_filename_component(
                WAYLAND_EGL_LIBRARY
                ${WAYLAND_EGL_LIBRARY}
                NAME
        )

        set(WAYLAND_CLIENT_FOUND 1)
        set(WAYLAND_EGL_FOUND 1)
        set(FENNEC_GRAPHICS_WANT_EGL 1)

        fennec_add_sources(
                # Dynamic Library Files
                include/fennec/platform/linux/wayland/lib/sym.h
                include/fennec/platform/linux/wayland/lib/wayland.h
                include/fennec/platform/linux/wayland/lib/loader.h source/platform/linux/wayland/lib/loader.cpp

                # Fennec Files
                include/fennec/platform/linux/wayland/fwd.h
                include/fennec/platform/linux/wayland/server.h source/platform/linux/wayland/server.cpp
                include/fennec/platform/linux/wayland/window.h source/platform/linux/wayland/window.cpp

                # EGL
                include/fennec/platform/linux/wayland/egl/context.h source/platform/linux/wayland/egl/context.cpp
                include/fennec/platform/linux/wayland/egl/surface.h source/platform/linux/wayland/egl/surface.cpp
        )

        fennec_add_definitions(
                FENNEC_HAS_WAYLAND=1
                FENNEC_LIB_WAYLAND="${WAYLAND_CLIENT_LIBRARY}"
                FENNEC_LIB_WAYLAND_EGL="${WAYLAND_EGL_LIBRARY}"
        )
    endif()
endmacro()