gtad/*: optimise and use latest GTAD features

- The generated code is updated to be compatible with the BaseJob
  changes introduced in the previous commit. This includes greatly
  reducing the number of header files that have to be explicitly
  #included, as basejob.h now #includes converters.h. Also, thanks to
  the changes in BaseJob, none of generated job classes needs
  a pimpl Private class.
- gtad/template.*.mustache files are replaced with data.h.mustache for
  data structures (entirely defined in header files from now on) and
  operation.*.mustache for API operations (also massively moved to
  header files, possibly also becoming header-only in the future).
- New variable-dropping and title-overring features in GTAD 0.7 allow
  to use the upstream matrix-doc repo to generate the code.
- CMakeLists.txt makes use of file globbing with CONFIGURE_DEPENDS
  where possible to alleviate build reconfiguration after a GTAD call.

1 files changed, 28 insertions, 23 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1e336673..c61c2682 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -184,21 +184,21 @@ set(lib_SRCS
 )
 
 set(CSAPI_DIR csapi)
+set(FULL_CSAPI_DIR lib/${CSAPI_DIR})
 set(ASAPI_DEF_DIR application-service/definitions)
 set(ISAPI_DEF_DIR identity/definitions)
 
-foreach (D ${CSAPI_DIR} ${CSAPI_DIR}/definitions
-         ${CSAPI_DIR}/definitions/wellknown ${ASAPI_DEF_DIR} ${ISAPI_DEF_DIR})
-    aux_source_directory(lib/${D} api_SRCS)
-endforeach()
+if (CMAKE_VERSION VERSION_GREATER_EQUAL "3.12.0")
+    set(add_CONFIGURE_DEPENDS "CONFIGURE_DEPENDS")
+endif()
+file(GLOB_RECURSE api_SRCS ${add_CONFIGURE_DEPENDS} ${FULL_CSAPI_DIR}/*.cpp)
 
 # Make no mistake: CMake cannot run gtad first and then populate the list of
-# resulting api_SRCS files. In other words, placing the above foreach after
-# the custom targets definition won't bring the desired result:
+# resulting api_SRCS files. In other words, placing the above statement after
+# the add_custom_target() call below won't bring the desired result:
 # CMake will execute it at cmake invocation and gtad will only run later
 # when building the update-api target. If you see that gtad has created
-# new files you have to re-run cmake.
-# TODO: check `file(GLOB_RECURSE ... CONFIGURE_DEPENDS)` (from CMake 3.14)
+# new files you have to re-run cmake. CONFIGURE_DEPENDS somewhat helps that.
 if (MATRIX_DOC_PATH AND GTAD_PATH)
     set(FULL_CSAPI_SRC_DIR ${ABS_API_DEF_PATH}/client-server)
     file(GLOB_RECURSE API_DEFS RELATIVE ${PROJECT_SOURCE_DIR}
@@ -206,7 +206,7 @@ if (MATRIX_DOC_PATH AND GTAD_PATH)
         ${ABS_API_DEF_PATH}/${ASAPI_DEF_DIR}/*.yaml
         ${ABS_API_DEF_PATH}/${ISAPI_DEF_DIR}/*.yaml
     )
-    add_custom_target(update-api
+    add_custom_target(generate-unformatted-api
         ${ABS_GTAD_PATH} --config ../gtad/gtad.yaml --out ${CSAPI_DIR}
             ${FULL_CSAPI_SRC_DIR}
             old_sync.yaml- room_initial_sync.yaml- # deprecated
@@ -214,25 +214,30 @@ if (MATRIX_DOC_PATH AND GTAD_PATH)
             sync.yaml- # we have a better handcrafted implementation
         WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}/lib
         SOURCES gtad/gtad.yaml
-                gtad/template.h.mustache
-                gtad/template.cpp.mustache
+                gtad/data.h.mustache
+                gtad/operation.h.mustache
+                gtad/operation.cpp.mustache
                 ${API_DEFS}
         VERBATIM
     )
     if (ABS_CLANG_FORMAT)
-        # TODO: list(TRANSFORM) is available from CMake 3.12
-        foreach (S ${api_SRCS})
-            string (REGEX REPLACE ".cpp$" ".h" H ${S})
-            list(APPEND api_HDRS ${H})
-        endforeach()
         set(CLANG_FORMAT_ARGS -i -sort-includes ${CLANG_FORMAT_ARGS})
-        add_custom_command(TARGET update-api POST_BUILD
-            COMMAND ${ABS_CLANG_FORMAT} ${CLANG_FORMAT_ARGS} ${api_SRCS}
-            COMMAND ${ABS_CLANG_FORMAT} ${CLANG_FORMAT_ARGS} ${api_HDRS}
-            WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
-            VERBATIM
-            COMMENT "Formatting files"
-        )
+        # FIXME: the list of files should be produced after GTAD has run.
+        # For now it's produced at CMake invocation; and if file() doesn't file
+        # any files clang-format chokes; also,
+        file(GLOB_RECURSE api_ALL_SRCS ${add_CONFIGURE_DEPENDS}
+             ${FULL_CSAPI_DIR}/*.*
+             lib/${ASAPI_DEF_DIR}/*.*
+             lib/${ISAPI_DEF_DIR}/*.*)
+        if (api_ALL_SRCS)
+            add_custom_target(format-api
+                ${ABS_CLANG_FORMAT} ${CLANG_FORMAT_ARGS} ${api_ALL_SRCS}
+                DEPENDS generate-unformatted-api
+                VERBATIM)
+            add_custom_target(update-api DEPENDS format-api)
+        else()
+            add_custom_target(update-api DEPENDS generate-unformatted-api)
+        endif()
     endif()
 endif()