#!/usr/bin/env bash

set -e -u

REPO_DIR=$(realpath "$(dirname "$0")/../")
PACKAGES_DIR="$REPO_DIR/packages"

check_package_license() {
	local pkg_licenses=$1
	local license
	local license_ok=true

	IFS=","
	for license in $pkg_licenses; do
		license=$(echo "$license" | sed -r 's/^\s*(\S+(\s+\S+)*)\s*$/\1/')

		case "$license" in
			AFL-2.1|AFL-3.0|AGPL-V3|APL-1.0|APSL-2.0|Apache-1.0|Apache-1.1);;
			Apache-2.0|Artistic-License-2.0|Attribution|BSD|"BSD 2-Clause");;
			"BSD 3-Clause"|"BSD New"|"BSD Simplified"|BSL-1.0|Bouncy-Castle);;
			CA-TOSL-1.1|CC0-1.0|CDDL-1.0|CDDL-1.1|CPAL-1.0|CPL-1.0|CPOL);;
			CPOL-1.02|CUAOFFICE-1.0|CeCILL-1|CeCILL-2|CeCILL-2.1|CeCILL-B);;
			CeCILL-C|Codehaus|Copyfree|Day|Day-Addendum|ECL2|EPL-1.0|EPL-2.0);;
			EUDATAGRID|EUPL-1.1|EUPL-1.2|Eiffel-2.0|Entessa-1.0);;
			Facebook-Platform|Fair|Frameworx-1.0|GPL-2.0|GPL-3.0|GPL-3.0-only);;
			GPL-3.0-or-later|Go|HSQLDB|Historical|IBMPL-1.0|IJG|IPAFont-1.0);;
			ISC|IU-Extreme-1.1.1|ImageMagick|JA-SIG|JSON|JTidy|LGPL-2.0);;
			LGPL-2.1|LGPL-3.0|LPPL-1.0|Libpng|Lucent-1.02|MIT|MPL-2.0|MS-PL);;
			MS-RL|MirOS|Motosoto-0.9.1|Mozilla-1.1|Multics|NASA-1.3|NAUMEN);;
			NCSA|NOSL-3.0|NTP|NUnit-2.6.3|NUnit-Test-Adapter-2.6.3|Nethack);;
			Nokia-1.0a|OCLC-2.0|OSL-3.0|OpenLDAP|OpenSSL|Openfont-1.1);;
			Opengroup|PHP-3.0|PHP-3.01|PostgreSQL|"Public Domain"|"Public Domain - SUN");;
			PythonPL|PythonSoftFoundation|QTPL-1.0|RPL-1.5|Real-1.0|RicohPL);;
			SUNPublic-1.0|Scala|SimPL-2.0|Sleepycat|Sybase-1.0|TMate|UPL-1.0);;
			Unicode-DFS-2015|Unlicense|UoI-NCSA|"VIM License"|VovidaPL-1.0|W3C);;
			WTFPL|Xnet|ZLIB|ZPL-2.0|wxWindows);;

			*)
				license_ok=false
				break
				;;
		esac
	done
	IFS=$old_ifs

	if $license_ok; then
		return 0
	else
		return 1
	fi
}

lint_package() {
	local package_script
	local package_name

	package_script=$1
	package_name=$(basename "$(dirname "$package_script")")

	echo "================================================================"
	echo
	echo "Package: $package_name"
	echo
	echo -n "Syntax check: "

	local syntax_errors
	syntax_errors=$(bash -n "$package_script" 2>&1)

	if [ -n "$syntax_errors" ]; then
		echo "FAILED"
		echo
		echo "$syntax_errors"
		echo

		return 1
	else
		echo "PASS"
	fi

	echo

	# Fields checking is done in subshell since we will source build.sh.
	(set +e +u
		local pkg_lint_error

		# Certain fields may be API-specific.
		# Using API 24 here.
		TERMUX_PKG_API_LEVEL=24

		if [ -f "$REPO_DIR/scripts/properties.sh" ]; then
			. "$REPO_DIR/scripts/properties.sh"
		fi

		. "$package_script"

		pkg_lint_error=false

		echo -n "TERMUX_PKG_HOMEPAGE: "
		if [ -n "$TERMUX_PKG_HOMEPAGE" ]; then
			if ! grep -qP '^https://.+' <<< "$TERMUX_PKG_HOMEPAGE"; then
				echo "NON-HTTPS (acceptable)"
			else
				echo "PASS"
			fi
		else
			echo "NOT SET"
			pkg_lint_error=true
		fi

		echo -n "TERMUX_PKG_DESCRIPTION: "
		if [ -n "$TERMUX_PKG_DESCRIPTION" ]; then
			str_length=$(($(wc -c <<< "$TERMUX_PKG_DESCRIPTION") - 1))

			if [ $str_length -gt 100 ]; then
				echo "TOO LONG (allowed: 100 characters max)"
			else
				echo "PASS"
			fi

			unset str_length
		else
			echo "NOT SET"
			pkg_lint_error=true
		fi

		echo -n "TERMUX_PKG_LICENSE: "
		if [ -n "$TERMUX_PKG_LICENSE" ]; then
			if [ "$TERMUX_PKG_LICENSE" = "custom" ]; then
				echo "CUSTOM"
			elif [ "$TERMUX_PKG_LICENSE" = "non-free" ]; then
				echo "NON-FREE"
			else
				if check_package_license "$TERMUX_PKG_LICENSE"; then
					echo "PASS"
				else
					echo "INVALID"
					pkg_lint_error=true
				fi
			fi
		else
			echo "NOT SET"
			pkg_lint_error=true
		fi

		echo -n "TERMUX_PKG_MAINTAINER: "
		if [ -n "$TERMUX_PKG_MAINTAINER" ]; then
			echo "PASS"
		else
			echo "NOT SET"
			pkg_lint_error=true
		fi

		if [ -n "$TERMUX_PKG_API_LEVEL" ]; then
			echo -n "TERMUX_PKG_API_LEVEL: "

			if grep -qP '^[1-9][0-9]$' <<< "$TERMUX_PKG_API_LEVEL"; then
				if [ $TERMUX_PKG_API_LEVEL -lt 24 ] || [ $TERMUX_PKG_API_LEVEL -gt 28 ]; then
					echo "INVALID (allowed: number in range 24 - 28)"
					pkg_lint_error=true
				else
					echo "PASS"
				fi
			else
				echo "INVALID (allowed: number in range 24 - 28)"
				pkg_lint_error=true
			fi
		fi

		echo -n "TERMUX_PKG_VERSION: "
		if [ -n "$TERMUX_PKG_VERSION" ]; then
			if grep -qiP '^[0-9][0-9a-z+\-\.]*' <<< "$TERMUX_PKG_VERSION"; then
				echo "PASS"
			else
				echo "INVALID (contains characters that are not allowed)"
			fi
		else
			echo "NOT SET"
			pkg_lint_error=true
		fi

		if [ -n "$TERMUX_PKG_REVISION" ]; then
			echo -n "TERMUX_PKG_REVISION: "

			if grep -qP '^[1-9](\d{1,8})?$' <<< "$TERMUX_PKG_REVISION"; then
				echo "PASS"
			else
				echo "INVALID (allowed: number in range 1 - 999999999)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_SKIP_SRC_EXTRACT" ]; then
			echo -n "TERMUX_PKG_SKIP_SRC_EXTRACT: "

			if [ "$TERMUX_PKG_SKIP_SRC_EXTRACT" = "true" ] || [ "$TERMUX_PKG_SKIP_SRC_EXTRACT" = "false" ]; then
				echo "PASS"
			else
				echo "INVALID (allowed: true / false)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_SRCURL" ]; then
			echo -n "TERMUX_PKG_SRCURL: "

			urls_ok=true
			for url in "${TERMUX_PKG_SRCURL[@]}"; do
				if [ -n "$url" ]; then
					if ! grep -qP '^https://.+' <<< "$url"; then
						echo "NON-HTTPS (acceptable)"
						urls_ok=false
						break
					fi
				else
					echo "NOT SET (one of the array elements)"
					urls_ok=false
					pkg_lint_error=true
					break
				fi
			done
			unset url

			if $urls_ok; then
				echo "PASS"
			fi
			unset urls_ok

			echo -n "TERMUX_PKG_SHA256: "
			if [ -n "$TERMUX_PKG_SHA256" ]; then
				if [ "${#TERMUX_PKG_SRCURL[@]}" -eq "${#TERMUX_PKG_SHA256[@]}" ]; then
					sha256_ok=true

					for sha256 in "${TERMUX_PKG_SHA256[@]}"; do
						if ! grep -qP '^[0-9a-fA-F]{64}$' <<< "${sha256}" && [ "$sha256" != "SKIP_CHECKSUM" ]; then
							echo "MALFORMED (SHA-256 should contain 64 hexadecimal numbers)"
							sha256_ok=false
							pkg_lint_error=true
							break
						fi
					done
					unset sha256

					if $sha256_ok; then
						echo "PASS"
					fi
					unset sha256_ok
				else
					echo "LENGTHS OF 'TERMUX_PKG_SRCURL' AND 'TERMUX_PKG_SHA256' ARE NOT EQUAL"
					pkg_lint_error=true
				fi
			elif [ "${TERMUX_PKG_SRCURL: -4}" == ".git" ]; then
				echo "NOT SET (acceptable since TERMUX_PKG_SRCURL is git repo)"
			else
				echo "NOT SET"
				pkg_lint_error=true
			fi
		else
			if [ "$TERMUX_PKG_SKIP_SRC_EXTRACT" != "true" ] && ! declare -F termux_step_extract_package > /dev/null 2>&1; then
				echo "TERMUX_PKG_SRCURL: NOT SET (set TERMUX_PKG_SKIP_SRC_EXTRACT to 'true' if no sources downloaded)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_METAPACKAGE" ]; then
			echo -n "TERMUX_PKG_METAPACKAGE: "

			if [ "$TERMUX_PKG_METAPACKAGE" = "true" ] || [ "$TERMUX_PKG_METAPACKAGE" = "false" ]; then
				echo "PASS"
			else
				echo "INVALID (allowed: true / false)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_ESSENTIAL" ]; then
			echo -n "TERMUX_PKG_ESSENTIAL: "
			if [ "$TERMUX_PKG_ESSENTIAL" = "true" ] || [ "$TERMUX_PKG_ESSENTIAL" = "false" ]; then
				echo "PASS"
			else
				echo "INVALID (allowed: true / false)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_NO_STATICSPLIT" ]; then
			echo -n "TERMUX_PKG_NO_STATICSPLIT: "

			if [ "$TERMUX_PKG_NO_STATICSPLIT" = "true" ] || [ "$TERMUX_PKG_NO_STATICSPLIT" = "false" ]; then
				echo "PASS"
			else
				echo "INVALID (allowed: true / false)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_BUILD_IN_SRC" ]; then
			echo -n "TERMUX_PKG_BUILD_IN_SRC: "

			if [ "$TERMUX_PKG_BUILD_IN_SRC" = "true" ] || [ "$TERMUX_PKG_BUILD_IN_SRC" = "false" ]; then
				echo "PASS"
			else
				echo "INVALID (allowed: true / false)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_HAS_DEBUG" ]; then
			echo -n "TERMUX_PKG_HAS_DEBUG: "

			if [ "$TERMUX_PKG_HAS_DEBUG" = "true" ] || [ "$TERMUX_PKG_HAS_DEBUG" = "false" ]; then
				echo "PASS"
			else
				echo "INVALID (allowed: true / false)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_PLATFORM_INDEPENDENT" ]; then
			echo -n "TERMUX_PKG_PLATFORM_INDEPENDENT: "

			if [ "$TERMUX_PKG_PLATFORM_INDEPENDENT" = "true" ] || [ "$TERMUX_PKG_PLATFORM_INDEPENDENT" = "false" ]; then
				echo "PASS"
			else
				echo "INVALID (allowed: true / false)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_HOSTBUILD" ]; then
			echo -n "TERMUX_PKG_HOSTBUILD: "

			if [ "$TERMUX_PKG_HOSTBUILD" = "true" ] || [ "$TERMUX_PKG_HOSTBUILD" = "false" ]; then
				echo "PASS"
			else
				echo "INVALID (allowed: true / false)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_FORCE_CMAKE" ]; then
			echo -n "TERMUX_PKG_FORCE_CMAKE: "

			if [ "$TERMUX_PKG_FORCE_CMAKE" = "true" ] || [ "$TERMUX_PKG_FORCE_CMAKE" = "false" ]; then
				echo "PASS"
			else
				echo "INVALID (allowed: true / false)"
				pkg_lint_error=true
			fi
		fi

		if [ -n "$TERMUX_PKG_RM_AFTER_INSTALL" ]; then
			echo -n "TERMUX_PKG_RM_AFTER_INSTALL: "
			file_path_ok=true

			while read -r file_path; do
				[ -z "$file_path" ] && continue

				if grep -qP '^(\.\.)?/' <<< "$file_path"; then
					echo "INVALID (file path should be relative to prefix)"
					file_path_ok=false
					pkg_lint_error=true
					break
				fi
			done <<< "$TERMUX_PKG_RM_AFTER_INSTALL"
			unset file_path

			if $file_path_ok; then
				echo "PASS"
			fi
			unset file_path_ok
		fi

		if [ -n "$TERMUX_PKG_CONFFILES" ]; then
			echo -n "TERMUX_PKG_CONFFILES: "
			file_path_ok=true

			while read -r file_path; do
				[ -z "$file_path" ] && continue

				if grep -qP '^(\.\.)?/' <<< "$file_path"; then
					echo "INVALID (file path should be relative to prefix)"
					file_path_ok=false
					pkg_lint_error=true
					break
				fi
			done <<< "$TERMUX_PKG_CONFFILES"
			unset file_path

			if $file_path_ok; then
				echo "PASS"
			fi
			unset file_path_ok
		fi

		if [ -n "$TERMUX_PKG_SERVICE_SCRIPT" ]; then
			echo -n "TERMUX_PKG_SERVICE_SCRIPT: "
			array_length=${#TERMUX_PKG_SERVICE_SCRIPT[@]}
			if [ $(( $array_length & 1 )) -eq 1 ]; then
				echo "INVALID (TERMUX_PKG_SERVICE_SCRIPT has to be an array of even length)"
				pkg_lint_error=true
			else
				echo "PASS"
			fi
		fi

		if $pkg_lint_error; then
			exit 1
		else
			exit 0
		fi
	)

	local ret=$?

	echo

	return "$ret"
}

linter_main() {
	local package_counter=0
	local problems_found=false
	local package_script

	for package_script in "$@"; do
		if ! lint_package "$package_script"; then
			problems_found=true
			break
		fi

		package_counter=$((package_counter + 1))
	done

	if $problems_found; then
		echo "================================================================"
		echo
		echo "A problem has been found in '$(realpath --relative-to="$REPO_DIR" "$package_script")'."
		echo "Checked $package_counter packages before the first error was detected."
		echo
		echo "================================================================"

		return 1
	else
		echo "================================================================"
		echo
		echo "Checked $package_counter packages."
		echo "Everything seems ok."
		echo
		echo "================================================================"
	fi

	return 0
}

if [ $# -eq 0 ]; then
	linter_main "$PACKAGES_DIR"/*/build.sh || exit 1
else
	linter_main "$@" || exit 1
fi