# SPDX-License-Identifier: BSD-3-Clause

# Generates header for which version is taken from (in order of precedence):
# 	1) .tarball-version file
#	2) git
#
# Version is checked during configuration step and for every target
# that has check_version_h target as dependency

cmake_minimum_required(VERSION 3.13)

set(VERSION_CMAKE_PATH ${CMAKE_CURRENT_LIST_DIR}/version.cmake)


# In an ideal world, every CI engine records the most basic and most
# important information:
# - current date and time
# - git version of the pull request
# - git version of the moving branch it's being merged with
#
# In the real world, some CI results use a random timezone without
# telling which one or don't provide any time at all.
string(TIMESTAMP build_start_time UTC)
message(STATUS "SOF version.cmake starting at ${build_start_time} UTC")

# Most CI engines test a temporary merge of the pull request with a
# moving target: the latest target branch. In that case the HEAD SHA is
# very volatile and the --parents are much more relevant and useful.
#
# --no-abbrev-commit because some git servers like github allow fetching
# by full length SHA (others forbid this entirely, see last page of
# `git help fetch-pack`)
message(STATUS "${SOF_ROOT_SOURCE_DIRECTORY} is at git commit with parent(s):")
# Note execute_process() failures are ignored by default (missing git...)
execute_process(
	COMMAND git -C "${SOF_ROOT_SOURCE_DIRECTORY}"
		log --parents --no-abbrev-commit --decorate -n 1 HEAD
	)


# Don't confuse this manual _input_ file with the other, output file of
# the same name auto-generated in the top _build_ directory by "make
# dist", see dist.cmake
set(TARBALL_VERSION_FILE_NAME ".tarball-version")

set(TARBALL_VERSION_SOURCE_PATH "${SOF_ROOT_SOURCE_DIRECTORY}/${TARBALL_VERSION_FILE_NAME}")

if(EXISTS ${TARBALL_VERSION_SOURCE_PATH})
	file(STRINGS ${TARBALL_VERSION_SOURCE_PATH} lines ENCODING "UTF-8")
	list(GET lines 0 GIT_TAG)
	list(GET lines 1 GIT_LOG_HASH)
	message(STATUS "Found ${TARBALL_VERSION_SOURCE_PATH}")
else()
	# execute_process() errors are not fatal by default!
	execute_process(
	        COMMAND git describe --tags --abbrev=12 --match v* --dirty
		WORKING_DIRECTORY ${SOF_ROOT_SOURCE_DIRECTORY}
		OUTPUT_VARIABLE GIT_TAG
		OUTPUT_STRIP_TRAILING_WHITESPACE
	)

	execute_process(COMMAND git log --pretty=format:%h -1
		WORKING_DIRECTORY ${SOF_ROOT_SOURCE_DIRECTORY}
		OUTPUT_VARIABLE GIT_LOG_HASH
		OUTPUT_STRIP_TRAILING_WHITESPACE
	)
endif()

if(NOT GIT_TAG MATCHES "^v")
	message(WARNING
	  "git describe found ${GIT_TAG} / nothing starting with 'v'. Shallow clone?")
	set(GIT_TAG "v0.0-0-g0000")
endif()

message(STATUS "GIT_TAG / GIT_LOG_HASH : ${GIT_TAG} / ${GIT_LOG_HASH}")

string(REGEX MATCH "^v([0-9]+)[.]([0-9]+)([.]([0-9]+))?" ignored "${GIT_TAG}")
set(SOF_MAJOR ${CMAKE_MATCH_1})
set(SOF_MINOR ${CMAKE_MATCH_2})
set(SOF_MICRO ${CMAKE_MATCH_4})

if(NOT SOF_MICRO MATCHES "^[0-9]+$")
	set(SOF_MICRO 0)
endif()

string(SUBSTRING "${GIT_LOG_HASH}" 0 5 SOF_TAG)
if(NOT SOF_TAG)
	set(SOF_TAG 0)
endif()

# Calculate source hash value, used to check ldc file and firmware compatibility
if(EXISTS ${SOF_ROOT_SOURCE_DIRECTORY}/.git/)
	set(SOURCE_HASH_DIR "${SOF_ROOT_BINARY_DIRECTORY}/source_hash")
	file(MAKE_DIRECTORY ${SOURCE_HASH_DIR})

	# When building with Zephyr, add a few extra files so the XTOS
	# and Zephyr .ldc files (which have different content!) do not
	# end up with the exact same "source checksum". The concept of
	# source checksum is flawed (see issue #3890) but this is much
	# better than nothing at all.
	#
	# Warning: ZEPHYR_CURRENT_MODULE_DIR is _undefined_ the first
	# time we're run and _defined empty_ the second time.  To
	# understand why look at the check_version_h target below.
	if("${ZEPHYR_CURRENT_MODULE_DIR}" STREQUAL "")
	  set(_sof_zephyr_dir "")
	else()
	  set(_sof_zephyr_dir "zephyr/")
	endif()

	# list tracked files from src directory
	execute_process(COMMAND git ls-files src/ scripts/ ${_sof_zephyr_dir}
			WORKING_DIRECTORY ${SOF_ROOT_SOURCE_DIRECTORY}
			OUTPUT_FILE "${SOURCE_HASH_DIR}/tracked_file_list"
		)
	# calculate hash of each listed files (from file version saved in file system)
	execute_process(COMMAND git hash-object --stdin-paths
			WORKING_DIRECTORY ${SOF_ROOT_SOURCE_DIRECTORY}
			INPUT_FILE "${SOURCE_HASH_DIR}/tracked_file_list"
			OUTPUT_FILE "${SOURCE_HASH_DIR}/tracked_file_hash_list"
		)
	# then calculate single hash of previously calculated hash list
	execute_process(COMMAND git hash-object --stdin
			WORKING_DIRECTORY ${SOF_ROOT_SOURCE_DIRECTORY}
			OUTPUT_STRIP_TRAILING_WHITESPACE
			INPUT_FILE "${SOURCE_HASH_DIR}/tracked_file_hash_list"
			OUTPUT_VARIABLE SOF_SRC_HASH_LONG
		)
	string(SUBSTRING ${SOF_SRC_HASH_LONG} 0 8 SOF_SRC_HASH)
	message(STATUS "Source content hash: ${SOF_SRC_HASH}. \
Note: by design, source hash is broken by config changes. See #3890.")
else() # Zephyr, tarball,...
	if(NOT "${GIT_LOG_HASH}" STREQUAL "")
		string(SUBSTRING "${GIT_LOG_HASH}" 0 8 SOF_SRC_HASH)
	else()
		set(SOF_SRC_HASH "baadf00d")
	endif()
	message(WARNING "${SOF_ROOT_SOURCE_DIRECTORY}/.git not found, \
source content hash cannot computed for the .ldc. Using SOF_SRC_HASH=${SOF_SRC_HASH} \
from GIT_LOG_HASH instead")
endif()

# for SOF_BUILD
include(${CMAKE_CURRENT_LIST_DIR}/version-build-counter.cmake)

# (Re)-generate "${VERSION_H_PATH}" but overwrite the old one only if
# different to avoid a full rebuild.  TODO: check how Zephyr solves this
# problem, see Zephyr commit 91709778a4878c
#
# This function is called only below; not supposed to be used elsewhere.
# This entire file is run at CMake configure time _and_ invoked
# again at build time.
function(sof_check_version_h)
	string(CONCAT header_content
		"#define SOF_MAJOR ${SOF_MAJOR}\n"
		"#define SOF_MINOR ${SOF_MINOR}\n"
		"#define SOF_MICRO ${SOF_MICRO}\n"
		"#define SOF_TAG \"${SOF_TAG}\"\n"
		"#define SOF_BUILD ${SOF_BUILD}\n"
		"#define SOF_GIT_TAG \"${GIT_TAG}\"\n"
		"#define SOF_SRC_HASH 0x${SOF_SRC_HASH}\n"
	)

	if(EXISTS "${VERSION_H_PATH}")
		file(READ "${VERSION_H_PATH}" old_version_content)
		if("${header_content}" STREQUAL "${old_version_content}")
			message(STATUS "Unchanged ${VERSION_H_PATH}")
			return()
		endif()
	endif()

	file(WRITE "${VERSION_H_PATH}" "${header_content}")
	message(STATUS "Generated new ${VERSION_H_PATH}")
endfunction()

# This ${VERSION_CMAKE_PATH} file is run in two (very) different ways:
#
# 1. explicitly included by some other, top-level CMakeLists.txt file, and
# 2. directly and "recursively" invoking itself with 'cmake -P myself' here.
#
# Add this check_version_h target only in case 1. (no "infinite recursion")
if("${CMAKE_SCRIPT_MODE_FILE}" STREQUAL "")
	add_custom_target(
		check_version_h
		BYPRODUCTS ${VERSION_H_PATH}
		COMMAND ${CMAKE_COMMAND}
			-DVERSION_H_PATH=${VERSION_H_PATH}
			-DSOF_ROOT_SOURCE_DIRECTORY=${SOF_ROOT_SOURCE_DIRECTORY}
			-DSOF_ROOT_BINARY_DIRECTORY=${SOF_ROOT_BINARY_DIRECTORY}
			-DZEPHYR_CURRENT_MODULE_DIR=${ZEPHYR_CURRENT_MODULE_DIR}
			-P ${VERSION_CMAKE_PATH}
		COMMENT "cmake -P ${VERSION_CMAKE_PATH}"
		VERBATIM
		USES_TERMINAL
	)
endif()

sof_check_version_h()