#
# This file is distributed under the MIT License. See LICENSE.md for details.
#

# Extracts definitions and generates C++ headers and implementations from the
# given header files.
# The definitions must be embedded as described in the docs for
# tuple_tree_generator_extract_definitions_from_headers.
function(tuple_tree_generator
  # Name of the target to generate the code
  TARGET_NAME
  # List of C++ headers
  HEADERS
  # Delimiter used to mark comments embedding type schemas
  DELIMITER
  NAMESPACE
  # Where the schema will be collected
  SCHEMA_PATH
  # Directory where the headers will be generated
  HEADERS_DIR
  # Include path prefix
  INCLUDE_PATH_PREFIX
  # Variable will be filled with the list of generated C++ headers
  GENERATED_HEADERS_VARIABLE
  # Variable will be filled with the list of generated C++ source files
  GENERATED_IMPLS_VARIABLE
  # Where the JSON schema will be produced (empty for no schema)
  JSONSCHEMA_PATH
  # Type to use as the root of the JSON schema
  JSONSCHEMA_ROOT_TYPE
  # Types equivalent to strings
  STRING_TYPES
  # Types equivalent to strings which get a separate type definition
  SEPARATE_STRING_TYPES
)
  #
  # Collect all the definitions in a single YAML document
  #
  tuple_tree_generator_extract_definitions_from_headers(
    "${HEADERS}"
    "${DELIMITER}"
    "${SCHEMA_PATH}"
  )

  #
  # C++ headers and implementation generation
  #
  tuple_tree_generator_compute_generated_cpp_files(
    "${HEADERS}"
    "${HEADERS_DIR}"
    LOCAL_GENERATED_HEADERS
    LOCAL_GENERATED_IMPLS
  )

  tuple_tree_generator_generate_cpp(
    "${SCHEMA_PATH}"
    "${NAMESPACE}"
    "${HEADERS_DIR}"
    "${INCLUDE_PATH_PREFIX}"
    "${LOCAL_GENERATED_HEADERS}"
    "${LOCAL_GENERATED_IMPLS}"
  )

  set("${GENERATED_HEADERS_VARIABLE}" ${LOCAL_GENERATED_HEADERS} PARENT_SCOPE)
  set("${GENERATED_IMPLS_VARIABLE}" ${LOCAL_GENERATED_IMPLS} PARENT_SCOPE)

  #
  # Produce JSON schema, if requested
  #
  if(NOT "${JSONSCHEMA_PATH}" STREQUAL "")
    tuple_tree_generator_generate_jsonschema(
      "${SCHEMA_PATH}"
      "${NAMESPACE}"
      "${JSONSCHEMA_ROOT_TYPE}"
      "${STRING_TYPES}"
      "${SEPARATE_STRING_TYPES}"
      "${JSONSCHEMA_PATH}"
    )
  endif()

  add_custom_target(
    "${TARGET_NAME}"
    DEPENDS
    "${SCHEMA_PATH}"
    ${LOCAL_GENERATED_HEADERS}
    ${LOCAL_GENERATED_IMPLS}
    ${JSONSCHEMA_PATH}
  )
endfunction()

# Extracts tuple_tree_generator YAML definitions from the given header files
#
# The definitions have to be embedded in a c-style comment marked with the given
# delimiter, like so:
#
# /* DELIMITER
# <definition>
# DELIMITER */
function(tuple_tree_generator_extract_definitions_from_headers HEADERS DELIMITER OUTPUT_FILE)
  add_custom_command(
    OUTPUT "${OUTPUT_FILE}"
    COMMAND "${CMAKE_SOURCE_DIR}/scripts/tuple_tree_generator/extract_yaml.py"
    --output "${OUTPUT_FILE}"
    "${DELIMITER}"
    ${HEADERS}
    DEPENDS ${HEADERS}
  )
endfunction()

# Computes the list of headers and C++ source files that will be generated by
# tuple_tree_generator.
# Note: the output variables will be overwritten
function(tuple_tree_generator_compute_generated_cpp_files
  SOURCE_HEADERS
  HEADERS_DIR
  GENERATED_HEADERS_VARIABLE
  GENERATED_IMPLS_VARIABLE
)
  # Empty output variables
  set(LOCAL_GENERATED_HEADERS_VARIABLE "${HEADERS_DIR}/ForwardDecls.h")
  set(LOCAL_GENERATED_IMPLS_VARIABLE)

  foreach(HEADER ${SOURCE_HEADERS})
    # TODO: we should not be generating /Impl/*.cpp files in an include/* directory
    # TODO: this piece of code is tightly coupled with cppheaders.py
    get_filename_component(HEADER_FILENAME "${HEADER}" NAME)
    get_filename_component(HEADER_FILENAME_WE "${HEADER}" NAME_WE)
    set(EARLY_OUTPUT "${HEADERS_DIR}/Early/${HEADER_FILENAME}")
    set(LATE_OUTPUT "${HEADERS_DIR}/Late/${HEADER_FILENAME}")
    set(IMPL_OUTPUT "${HEADERS_DIR}/Impl/${HEADER_FILENAME_WE}.cpp")
    list(APPEND LOCAL_GENERATED_HEADERS_VARIABLE "${EARLY_OUTPUT}")
    list(APPEND LOCAL_GENERATED_HEADERS_VARIABLE "${LATE_OUTPUT}")
    list(APPEND LOCAL_GENERATED_IMPLS_VARIABLE "${IMPL_OUTPUT}")
  endforeach()
  set("${GENERATED_HEADERS_VARIABLE}" ${LOCAL_GENERATED_HEADERS_VARIABLE} PARENT_SCOPE)
  set("${GENERATED_IMPLS_VARIABLE}" ${LOCAL_GENERATED_IMPLS_VARIABLE} PARENT_SCOPE)
endfunction()


set(TEMPLATES_DIR "${CMAKE_SOURCE_DIR}/scripts/tuple_tree_generator/tuple_tree_generator/templates")
set(TEMPLATES
  "${TEMPLATES_DIR}/class_forward_decls.h.tpl"
  "${TEMPLATES_DIR}/enum.h.tpl"
  "${TEMPLATES_DIR}/struct.h.tpl"
  "${TEMPLATES_DIR}/struct_forward_decls.h.tpl"
  "${TEMPLATES_DIR}/struct_late.h.tpl"
  "${TEMPLATES_DIR}/struct_impl.cpp.tpl"
)

set(SCRIPTS_ROOT_DIR "${CMAKE_SOURCE_DIR}/scripts/tuple_tree_generator")
# The list of Python scripts is build as follows:
#
# find scripts/tuple_tree_generator -name "*.py" | sort | sed 's|scripts/tuple_tree_generator|"\${SCRIPTS_ROOT_DIR}|; s/$/"/'
#
# TODO: detect and warn about extra files in those directories
set(TUPLE_TREE_GENERATOR_SOURCES
  "${SCRIPTS_ROOT_DIR}/extract_yaml.py"
  "${SCRIPTS_ROOT_DIR}/tuple-tree-generate-cpp.py"
  "${SCRIPTS_ROOT_DIR}/tuple-tree-generate-jsonschema.py"
  "${SCRIPTS_ROOT_DIR}/tuple_tree_generator/__init__.py"
  "${SCRIPTS_ROOT_DIR}/tuple_tree_generator/generators/__init__.py"
  "${SCRIPTS_ROOT_DIR}/tuple_tree_generator/generators/cppheaders.py"
  "${SCRIPTS_ROOT_DIR}/tuple_tree_generator/generators/jinja_utils.py"
  "${SCRIPTS_ROOT_DIR}/tuple_tree_generator/generators/jsonschema.py"
  "${SCRIPTS_ROOT_DIR}/tuple_tree_generator/schema/__init__.py"
  "${SCRIPTS_ROOT_DIR}/tuple_tree_generator/schema/definition.py"
  "${SCRIPTS_ROOT_DIR}/tuple_tree_generator/schema/enum.py"
  "${SCRIPTS_ROOT_DIR}/tuple_tree_generator/schema/schema.py"
  "${SCRIPTS_ROOT_DIR}/tuple_tree_generator/schema/struct.py"
)

# Generates headers and implementation C++ files
function(tuple_tree_generator_generate_cpp
  # Path to the yaml definitions
  YAML_DEFINITIONS
  # Base namespace of the generated classes (e.g. model)
  NAMESPACE
  # Output directory
  OUTPUT_DIR
  # Include path prefix
  INCLUDE_PATH_PREFIX
  # List of headers that are expected to be generated
  EXPECTED_GENERATED_HEADERS
  # List of implementation files expected to be generated
  EXPECTED_GENERATED_IMPLS
)
  add_custom_command(
    COMMAND "${SCRIPTS_ROOT_DIR}/tuple-tree-generate-cpp.py"
            --namespace "${NAMESPACE}"
            --include-path-prefix "${INCLUDE_PATH_PREFIX}"
            "${YAML_DEFINITIONS}"
            "${OUTPUT_DIR}"
    OUTPUT ${EXPECTED_GENERATED_HEADERS} ${EXPECTED_GENERATED_IMPLS}
    DEPENDS
      "${YAML_DEFINITIONS}"
      ${TEMPLATES}
      "${SCRIPTS_ROOT_DIR}/extract_yaml.py"
      ${TUPLE_TREE_GENERATOR_SOURCES}
  )
endfunction()

# Generates JSON schema files
function(tuple_tree_generator_generate_jsonschema
  YAML_DEFINITIONS              # Path to the yaml definitions
  NAMESPACE                     # Base namespace of the generated classes (e.g. model)
  JSONSCHEMA_ROOT_TYPE          # Type to use as the root of the JSON schema
  STRING_TYPES                  # Types equivalent to plain strings
  SEPARATE_STRING_TYPES         # Types equivalent to plain strings that get a separate type definition
  OUTPUT_PATH                   # Output path
)
  set(STRING_TYPE_ARGS)
  foreach(ST ${STRING_TYPES})
    list(APPEND STRING_TYPE_ARGS --string-type "${ST}")
  endforeach()

  set(SEPARATE_STRING_TYPE_ARGS)
  foreach(ST ${SEPARATE_STRING_TYPES})
    list(APPEND SEPARATE_STRING_TYPE_ARGS --separate-string-type "${ST}")
  endforeach()

  add_custom_command(
    COMMAND "${SCRIPTS_ROOT_DIR}/tuple-tree-generate-jsonschema.py"
            --namespace "${NAMESPACE}"
            --root-type "${JSONSCHEMA_ROOT_TYPE}"
            --output "${OUTPUT_PATH}"
            ${STRING_TYPE_ARGS}
            ${SEPARATE_STRING_TYPE_ARGS}
            "${YAML_DEFINITIONS}"
    OUTPUT "${OUTPUT_PATH}"
    DEPENDS "${YAML_DEFINITIONS}" ${TUPLE_TREE_GENERATOR_SOURCES}
  )
endfunction()

function(
  target_tuple_tree_and_schema_generate
  HEADER_DIRECTORY
  NAMESPACE
  SCHEMA_PATH
  TARGET_ID
  JSONSCHEMA_PATH
  JSONSCHEMA_ROOT_TYPE
  STRING_TYPES
  SEPARATE_STRING_TYPES
  )

# Generate C++ headers from the collected YAML
set(OUTPUT_DIR "${CMAKE_BINARY_DIR}/include/revng/${HEADER_DIRECTORY}/Generated")
tuple_tree_generator(
  generate-${TARGET_ID}-tuple-tree-code
  "${ARGN}"
  TUPLE-TREE-YAML
  ${NAMESPACE}
  "${SCHEMA_PATH}"
  "${OUTPUT_DIR}"
  "revng/${HEADER_DIRECTORY}"
  GENERATED_HEADERS
  GENERATED_IMPLS
  "${JSONSCHEMA_PATH}"
  ${JSONSCHEMA_ROOT_TYPE}
  "${STRING_TYPES}"
  "${SEPARATE_STRING_TYPES}"
)

install(
  DIRECTORY ${OUTPUT_DIR}
  DESTINATION include/revng/${HEADER_DIRECTORY}
)

target_sources(${TARGET_ID} PRIVATE ${GENERATED_IMPLS})

add_dependencies(${TARGET_ID} generate-${TARGET_ID}-tuple-tree-code)

endfunction()

function(
  target_tuple_tree_generate
  HEADER_DIRECTORY
  NAMESPACE
  SCHEMA_PATH
  TARGET_ID
  )
  target_tuple_tree_and_schema_generate(
    ${HEADER_DIRECTORY}
    ${NAMESPACE}
    ${SCHEMA_PATH}
    ${TARGET_ID}
    ""
    ${TARGET_ID}_schema
    ""
    ""
    "${ARGN}")
endfunction()