#!/usr/bin/env bash

readonly BASEDIR=$(readlink -f $(dirname $0))/..
cd $BASEDIR

# exit on errors
set -e

if ! hash nproc 2> /dev/null; then

	function nproc() {
		echo 8
	}

fi

function version_lt() {
	[ $(echo -e "$1\n$2" | sort -V | head -1) != "$1" ]
}

function array_contains_string() {
	name="$1[@]"
	array=("${!name}")

	for element in "${array[@]}"; do
		if [ "$element" = "$2" ]; then
			return $(true)
		fi
	done

	return $(false)
}

rc=0

echo -n "Checking file permissions..."

while read -r perm _res0 _res1 path; do
	if [ ! -f "$path" ]; then
		continue
	fi

	# Skip symlinks
	if [[ -L $path ]]; then
		continue
	fi
	fname=$(basename -- "$path")

	case ${fname##*.} in
		c | h | cpp | cc | cxx | hh | hpp | md | html | js | json | svg | Doxyfile | yml | LICENSE | README | conf | in | Makefile | mk | gitignore | go | txt)
			# These file types should never be executable
			if [ "$perm" -eq 100755 ]; then
				echo "ERROR: $path is marked executable but is a code file."
				rc=1
			fi
			;;
		*)
			shebang=$(head -n 1 $path | cut -c1-3)

			# git only tracks the execute bit, so will only ever return 755 or 644 as the permission.
			if [ "$perm" -eq 100755 ]; then
				# If the file has execute permission, it should start with a shebang.
				if [ "$shebang" != "#!/" ]; then
					echo "ERROR: $path is marked executable but does not start with a shebang."
					rc=1
				fi
			else
				# If the file doesnot have execute permissions, it should not start with a shebang.
				if [ "$shebang" = "#!/" ]; then
					echo "ERROR: $path is not marked executable but starts with a shebang."
					rc=1
				fi
			fi
			;;
	esac

done <<< "$(git grep -I --name-only --untracked -e . | git ls-files -s)"

if [ $rc -eq 0 ]; then
	echo " OK"
fi

if hash astyle; then
	echo -n "Checking coding style..."
	if [ "$(astyle -V)" \< "Artistic Style Version 3" ]; then
		echo -n " Your astyle version is too old so skipping coding style checks. Please update astyle to at least 3.0.1 version..."
	else
		rm -f astyle.log
		touch astyle.log
		# Exclude rte_vhost code imported from DPDK - we want to keep the original code
		#  as-is to enable ongoing work to synch with a generic upstream DPDK vhost library,
		#  rather than making diffs more complicated by a lot of changes to follow SPDK
		#  coding standards.
		git ls-files '*.[ch]' '*.cpp' '*.cc' '*.cxx' '*.hh' '*.hpp' \
			| grep -v rte_vhost | grep -v cpp_headers \
			| xargs -P$(nproc) -n10 astyle --options=.astylerc >> astyle.log
		if grep -q "^Formatted" astyle.log; then
			echo " errors detected"
			git diff --ignore-submodules=all
			sed -i -e 's/  / /g' astyle.log
			grep --color=auto "^Formatted.*" astyle.log
			echo "Incorrect code style detected in one or more files."
			echo "The files have been automatically formatted."
			echo "Remember to add the files to your commit."
			rc=1
		else
			echo " OK"
		fi
		rm -f astyle.log
	fi
else
	echo "You do not have astyle installed so your code style is not being checked!"
fi

GIT_VERSION=$(git --version | cut -d' ' -f3)

if version_lt "1.9.5" "${GIT_VERSION}"; then
	# git <1.9.5 doesn't support pathspec magic exclude
	echo " Your git version is too old to perform all tests. Please update git to at least 1.9.5 version..."
	exit 0
fi

echo -n "Checking comment style..."

git grep --line-number -e '\/[*][^ *-]' -- '*.[ch]' > comment.log || true
git grep --line-number -e '[^ ][*]\/' -- '*.[ch]' ':!lib/rte_vhost*/*' >> comment.log || true
git grep --line-number -e '^[*]' -- '*.[ch]' >> comment.log || true
git grep --line-number -e '\s\/\/' -- '*.[ch]' >> comment.log || true
git grep --line-number -e '^\/\/' -- '*.[ch]' >> comment.log || true

if [ -s comment.log ]; then
	echo " Incorrect comment formatting detected"
	cat comment.log
	rc=1
else
	echo " OK"
fi
rm -f comment.log

echo -n "Checking for spaces before tabs..."
git grep --line-number $' \t' -- './*' ':!*.patch' > whitespace.log || true
if [ -s whitespace.log ]; then
	echo " Spaces before tabs detected"
	cat whitespace.log
	rc=1
else
	echo " OK"
fi
rm -f whitespace.log

echo -n "Checking trailing whitespace in output strings..."

git grep --line-number -e ' \\n"' -- '*.[ch]' > whitespace.log || true

if [ -s whitespace.log ]; then
	echo " Incorrect trailing whitespace detected"
	cat whitespace.log
	rc=1
else
	echo " OK"
fi
rm -f whitespace.log

echo -n "Checking for use of forbidden library functions..."

git grep --line-number -w '\(atoi\|atol\|atoll\|strncpy\|strcpy\|strcat\|sprintf\|vsprintf\)' -- './*.c' ':!lib/rte_vhost*/**' > badfunc.log || true
if [ -s badfunc.log ]; then
	echo " Forbidden library functions detected"
	cat badfunc.log
	rc=1
else
	echo " OK"
fi
rm -f badfunc.log

echo -n "Checking for use of forbidden CUnit macros..."

git grep --line-number -w 'CU_ASSERT_FATAL' -- 'test/*' ':!test/spdk_cunit.h' > badcunit.log || true
if [ -s badcunit.log ]; then
	echo " Forbidden CU_ASSERT_FATAL usage detected - use SPDK_CU_ASSERT_FATAL instead"
	cat badcunit.log
	rc=1
else
	echo " OK"
fi
rm -f badcunit.log

echo -n "Checking blank lines at end of file..."

if ! git grep -I -l -e . -z './*' ':!*.patch' \
	| xargs -0 -P$(nproc) -n1 scripts/eofnl > eofnl.log; then
	echo " Incorrect end-of-file formatting detected"
	cat eofnl.log
	rc=1
else
	echo " OK"
fi
rm -f eofnl.log

echo -n "Checking for POSIX includes..."
git grep -I -i -f scripts/posix.txt -- './*' ':!include/spdk/stdinc.h' ':!include/linux/**' ':!lib/rte_vhost*/**' ':!scripts/posix.txt' ':!*.patch' > scripts/posix.log || true
if [ -s scripts/posix.log ]; then
	echo "POSIX includes detected. Please include spdk/stdinc.h instead."
	cat scripts/posix.log
	rc=1
else
	echo " OK"
fi
rm -f scripts/posix.log

echo -n "Checking for proper function naming conventions..."
# commit_to_compare = HEAD - 1.
commit_to_compare="$(git log --pretty=oneline --skip=1 -n 1 | awk '{print $1}')"
failed_naming_conventions=false
changed_c_libs=()
declared_symbols=()

# Build an array of all the modified C files.
mapfile -t changed_c_libs < <(git diff --name-only HEAD $commit_to_compare -- lib/**/*.c module/**/*.c)
# Matching groups are 1. qualifiers / return type. 2. function name 3. argument list / comments and stuff after that.
# Capture just the names of newly added (or modified) function definitions.
mapfile -t declared_symbols < <(git diff -U0 $commit_to_compare HEAD -- include/spdk*/*.h | sed -En 's/(^[+].*)(spdk[a-z,A-Z,0-9,_]*)(\(.*)/\2/p')

for c_file in "${changed_c_libs[@]}"; do
	lib_map_file="mk/spdk_blank.map"
	defined_symbols=()
	removed_symbols=()
	exported_symbols=()
	if ls "$(dirname $c_file)"/*.map &> /dev/null; then
		lib_map_file="$(ls "$(dirname $c_file)"/*.map)"
	fi
	# Matching groups are 1. leading +sign. 2, function name 3. argument list / anything after that.
	# Capture just the names of newly added (or modified) functions that start with "spdk_"
	mapfile -t defined_symbols < <(git diff -U0 $commit_to_compare HEAD -- $c_file | sed -En 's/(^[+])(spdk[a-z,A-Z,0-9,_]*)(\(.*)/\2/p')
	# Capture the names of removed symbols to catch edge cases where we just move definitions around.
	mapfile -t removed_symbols < <(git diff -U0 $commit_to_compare HEAD -- $c_file | sed -En 's/(^[-])(spdk[a-z,A-Z,0-9,_]*)(\(.*)/\2/p')
	for symbol in "${removed_symbols[@]}"; do
		defined_symbols=("${defined_symbols[@]/$symbol/}")
	done
	# It's possible that we just modified a functions arguments so unfortunately we can't just look at changed lines in this function.
	# matching groups are 1. All leading whitespace 2. function name. Capture just the symbol name.
	mapfile -t exported_symbols < <(sed -En 's/(^[[:space:]]*)(spdk[a-z,A-Z,0-9,_]*);/\2/p' < $lib_map_file)
	for defined_symbol in "${defined_symbols[@]}"; do
		# if the list of defined symbols is equal to the list of removed symbols, then we are left with a single empty element. skip it.
		if [ "$defined_symbol" = '' ]; then
			continue
		fi
		not_exported=true
		not_declared=true
		if array_contains_string exported_symbols $defined_symbol; then
			not_exported=false
		fi

		if array_contains_string declared_symbols $defined_symbol; then
			not_declared=false
		fi

		if $not_exported || $not_declared; then
			if ! $failed_naming_conventions; then
				echo " found naming convention errors."
			fi
			echo "function $defined_symbol starts with spdk_ which is reserved for public API functions."
			echo "Please add this function to its corresponding map file and a public header or remove the spdk_ prefix."
			failed_naming_conventions=true
			rc=1
		fi
	done
done

if ! $failed_naming_conventions; then
	echo " OK"
fi

echo -n "Checking #include style..."
git grep -I -i --line-number "#include <spdk/" -- '*.[ch]' > scripts/includes.log || true
if [ -s scripts/includes.log ]; then
	echo "Incorrect #include syntax. #includes of spdk/ files should use quotes."
	cat scripts/includes.log
	rc=1
else
	echo " OK"
fi
rm -f scripts/includes.log

if hash pycodestyle 2> /dev/null; then
	PEP8=pycodestyle
elif hash pep8 2> /dev/null; then
	PEP8=pep8
fi

if [ -n "${PEP8}" ]; then
	echo -n "Checking Python style..."

	PEP8_ARGS+=" --max-line-length=140"

	error=0
	git ls-files '*.py' | xargs -P$(nproc) -n1 $PEP8 $PEP8_ARGS > pep8.log || error=1
	if [ $error -ne 0 ]; then
		echo " Python formatting errors detected"
		cat pep8.log
		rc=1
	else
		echo " OK"
	fi
	rm -f pep8.log
else
	echo "You do not have pycodestyle or pep8 installed so your Python style is not being checked!"
fi

# find compatible shfmt binary
shfmt_bins=$(compgen -c | grep '^shfmt' || true)
for bin in $shfmt_bins; do
	if version_lt "$("$bin" --version)" "3.1.0"; then
		shfmt=$bin
		break
	fi
done

if [ -n "$shfmt" ]; then
	shfmt_cmdline=() silly_plural=()

	silly_plural[1]="s"

	commits=() sh_files=() sh_files_repo=() sh_files_staged=()

	mapfile -t sh_files_repo < <(git ls-files '*.sh')
	# Fetch .sh files only from the commits that are targeted for merge
	while read -r _ commit; do
		commits+=("$commit")
	done < <(git cherry -v origin/master)

	mapfile -t sh_files < <(git diff --name-only HEAD origin/master "${sh_files_repo[@]}")
	# In case of a call from a pre-commit git hook
	mapfile -t sh_files_staged < <(
		IFS="|"
		git diff --cached --name-only "${sh_files_repo[@]}" | grep -v "${sh_files[*]}"
	)

	if ((${#sh_files[@]})); then
		printf 'Checking .sh formatting style...'

		if ((${#sh_files_staged[@]})); then
			sh_files+=("${sh_files_staged[@]}")
		fi

		shfmt_cmdline+=(-i 0)     # indent_style = tab|indent_size = 0
		shfmt_cmdline+=(-bn)      # binary_next_line = true
		shfmt_cmdline+=(-ci)      # switch_case_indent = true
		shfmt_cmdline+=(-ln bash) # shell_variant = bash (default)
		shfmt_cmdline+=(-d)       # diffOut - print diff of the changes and exit with != 0
		shfmt_cmdline+=(-sr)      # redirect operators will be followed by a space

		diff=${output_dir:-$PWD}/$shfmt.patch

		# Explicitly tell shfmt to not look for .editorconfig. .editorconfig is also not looked up
		# in case any formatting arguments has been passed on its cmdline.
		if ! SHFMT_NO_EDITORCONFIG=true "$shfmt" "${shfmt_cmdline[@]}" "${sh_files[@]}" > "$diff"; then
			# In case shfmt detects an actual syntax error it will write out a proper message on
			# its stderr, hence the diff file should remain empty.
			if [[ -s $diff ]]; then
				diff_out=$(< "$diff")
			fi

			cat <<- ERROR_SHFMT

				* Errors in style formatting have been detected.
				${diff_out:+* Please, review the generated patch at $diff

				# _START_OF_THE_DIFF

				${diff_out:-ERROR}

				# _END_OF_THE_DIFF
				}

			ERROR_SHFMT
			rc=1
		else
			rm -f "$diff"
			printf ' OK\n'
		fi
	fi
else
	echo "shfmt not detected, Bash style formatting check is skipped"
fi

if hash shellcheck 2> /dev/null; then
	echo -n "Checking Bash style..."

	shellcheck_v=$(shellcheck --version | grep -P "version: [0-9\.]+" | cut -d " " -f2)

	# SHCK_EXCLUDE contains a list of all of the spellcheck errors found in SPDK scripts
	# currently. New errors should only be added to this list if the cost of fixing them
	# is deemed too high. For more information about the errors, go to:
	# https://github.com/koalaman/shellcheck/wiki/Checks
	# Error descriptions can also be found at: https://github.com/koalaman/shellcheck/wiki
	# SPDK fails some error checks which have been deprecated in later versions of shellcheck.
	# We will not try to fix these error checks, but instead just leave the error types here
	# so that we can still run with older versions of shellcheck.
	SHCK_EXCLUDE="SC1117"
	# SPDK has decided to not fix violations of these errors.
	# We are aware about below exclude list and we want this errors to be excluded.
	# SC1083: This {/} is literal. Check expression (missing ;/\n?) or quote it.
	# SC1090: Can't follow non-constant source. Use a directive to specify location.
	# SC1091: Not following: (error message here)
	# SC2001: See if you can use ${variable//search/replace} instead.
	# SC2010: Don't use ls | grep. Use a glob or a for loop with a condition to allow non-alphanumeric filenames.
	# SC2015: Note that A && B || C is not if-then-else. C may run when A is true.
	# SC2016: Expressions don't expand in single quotes, use double quotes for that.
	# SC2034: foo appears unused. Verify it or export it.
	# SC2046: Quote this to prevent word splitting.
	# SC2086: Double quote to prevent globbing and word splitting.
	# SC2119: Use foo "$@" if function's $1 should mean script's $1.
	# SC2120: foo references arguments, but none are ever passed.
	# SC2148: Add shebang to the top of your script.
	# SC2153: Possible Misspelling: MYVARIABLE may not be assigned, but MY_VARIABLE is.
	# SC2154: var is referenced but not assigned.
	# SC2164: Use cd ... || exit in case cd fails.
	# SC2174: When used with -p, -m only applies to the deepest directory.
	# SC2206: Quote to prevent word splitting/globbing,
	#         or split robustly with mapfile or read -a.
	# SC2207: Prefer mapfile or read -a to split command output (or quote to avoid splitting).
	# SC2223: This default assignment may cause DoS due to globbing. Quote it.
	SHCK_EXCLUDE="$SHCK_EXCLUDE,SC1083,SC1090,SC1091,SC2010,SC2015,SC2016,SC2034,SC2046,SC2086,\
SC2119,SC2120,SC2148,SC2153,SC2154,SC2164,SC2174,SC2001,SC2206,SC2207,SC2223"

	SHCK_FORMAT="diff"
	SHCK_APPLY=true
	if [ "$shellcheck_v" \< "0.7.0" ]; then
		SHCK_FORMAT="tty"
		SHCK_APPLY=false
	fi
	SHCH_ARGS=" -x -e $SHCK_EXCLUDE -f $SHCK_FORMAT"

	error=0
	git ls-files '*.sh' | xargs -P$(nproc) -n1 shellcheck $SHCH_ARGS &> shellcheck.log || error=1
	if [ $error -ne 0 ]; then
		echo " Bash formatting errors detected!"

		# Some errors are not auto-fixable. Fall back to tty output.
		if grep -q "Use another format to see them." shellcheck.log; then
			SHCK_FORMAT="tty"
			SHCK_APPLY=false
			SHCH_ARGS=" -e $SHCK_EXCLUDE -f $SHCK_FORMAT"
			git ls-files '*.sh' | xargs -P$(nproc) -n1 shellcheck $SHCH_ARGS > shellcheck.log || error=1
		fi

		cat shellcheck.log
		if $SHCK_APPLY; then
			git apply shellcheck.log
			echo "Bash errors were automatically corrected."
			echo "Please remember to add the changes to your commit."
		fi
		rc=1
	else
		echo " OK"
	fi
	rm -f shellcheck.log
else
	echo "You do not have shellcheck installed so your Bash style is not being checked!"
fi

# Check if any of the public interfaces were modified by this patch.
# Warn the user to consider updating the changelog any changes
# are detected.
echo -n "Checking whether CHANGELOG.md should be updated..."
staged=$(git diff --name-only --cached .)
working=$(git status -s --porcelain --ignore-submodules | grep -iv "??" | awk '{print $2}')
files="$staged $working"
if [[ "$files" = " " ]]; then
	files=$(git diff-tree --no-commit-id --name-only -r HEAD)
fi

has_changelog=0
for f in $files; do
	if [[ $f == CHANGELOG.md ]]; then
		# The user has a changelog entry, so exit.
		has_changelog=1
		break
	fi
done

needs_changelog=0
if [ $has_changelog -eq 0 ]; then
	for f in $files; do
		if [[ $f == include/spdk/* ]] || [[ $f == scripts/rpc.py ]] || [[ $f == etc/* ]]; then
			echo ""
			echo -n "$f was modified. Consider updating CHANGELOG.md."
			needs_changelog=1
		fi
	done
fi

if [ $needs_changelog -eq 0 ]; then
	echo " OK"
else
	echo ""
fi

exit $rc