class Collector::Postfix
	class Noqueue
		def initialize store, prometheus
			@store = store
			@noqueue = prometheus.counter :total, docstring: 'Total noqueued by reasons.', labels: %i[reason]
			@codes   = prometheus.counter :status_code_total, docstring: 'Total noqueued by status code', labels: %i[status_code enhanced_status_code]
			['dnsbl', 'no reverse hostname', 'user does not exist', '<any>'].each {|r| @noqueue.increment by: 0, labels: {reason: r} }
		end

		def collect entry
			case entry.message
			when /\ANOQUEUE: reject: RCPT from (?:[^ ]+): (\d+) (\d+\.\d+\.\d+) (?:[^ ]+): (.*?),/
				code, enh = $1, $2
				@codes.increment labels: {status_code: code, enhanced_status_code: enh}
			end
			case entry.message
			when /\ANOQUEUE: reject: RCPT from .* blocked using /
				@noqueue.increment labels: {reason: 'dnsbl'}
			when /\ANOQUEUE: reject: RCPT from .* Message rejected due to: SPF fail - not authorized\. /
				@noqueue.increment labels: {reason: 'spf fail'}
			when / Client host rejected: cannot find your reverse hostname/
				@noqueue.increment labels: {reason: 'no reverse hostname'}
			when / User doesn't exist: /
				@noqueue.increment labels: {reason: 'user does not exist'}
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier} NOQUEUE: #{entry.message}"
				@noqueue.increment labels: {reason: '<any>'}
			end
		end
	end

	class Cache
		def initialize store, prometheus
			@store = store
			@full_cleanup          = prometheus.counter :full_cleanup_total,                 docstring: 'A counter of total cache cleanups', labels: %i[file]
			@full_cleanup_retained = prometheus.gauge   :full_cleanup_retained_entries,      docstring: 'Retained entries of last cache cleanups', labels: %i[file]
			@full_cleanup_dropped  = prometheus.counter :full_cleanup_dropped_entries_total, docstring: 'Total dropped entries of cache cleanups', labels: %i[file]
		end

		def collect entry
			case entry.message
			when /\Acache (.*) full cleanup: retained=(\d+) dropped=(\d+) entries/
				# postscreen: cache lmdb:/var/lib/postfix/postscreen_cache full cleanup: retained=128 dropped=14 entries
				file, retained, dropped = $1, $2.to_f, $3.to_f
				@full_cleanup.increment labels: {file: file}
				@full_cleanup_retained.increment by: retained, labels: {file: file}
				@full_cleanup_dropped.increment by: dropped, labels: {file: file}
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier} cache: #{entry.message}"
			end
		end
	end

	class Postscreen
		def initialize store, prometheus
			@store = store
			@noqueue                 = Noqueue.new store, prometheus.prefix_proxy( :noqueue)
			@cache                   = Cache.new store,   prometheus.prefix_proxy( :cache)
			@connect_from            = prometheus.counter :connect_from_total,       docstring: 'A counter of connections to postscreen'
			@whitelisted             = prometheus.counter :whitelisted_total,        docstring: 'A counter of WHITELISTED connections to postscreen'
			@pass_old                = prometheus.counter :pass_old_total,           docstring: 'A counter of PASS OLD connections to postscreen'
			@pass_new                = prometheus.counter :pass_new_total,           docstring: 'A counter of PASS NEW connections to postscreen'
			@dnsbl                   = prometheus.counter :dnsbl_total,              docstring: 'A counter of DNSBL-blocked to postscreen'
			@bare_newline            = prometheus.counter :bare_newline_total,       docstring: 'A counter of BARE NEWLINE-blocked to postscreen'
			@command_pipelining      = prometheus.counter :command_pipelining_total, docstring: 'A counter of COMMAND PIPELINING-blocked to postscreen'
			@command_time_limit      = prometheus.counter :command_time_limit_total, docstring: 'A counter of COMMAND TIME LIMIT-blocked to postscreen'
			@hangup                  = prometheus.counter :hangup_total,             docstring: 'A counter of HANGUP to postscreen'
			@bdat                    = prometheus.counter :bdat_total,               docstring: 'A counter of BDAT to postscreen'
			@pregreet                = prometheus.counter :pregreet_total,           docstring: 'A counter of PREGREET to postscreen'
			@disconnect              = prometheus.counter :disconnect_total,         docstring: 'A counter of DISCONNECT to postscreen'
			@unknown                 = prometheus.counter :unknown_total,            docstring: 'A counter of unknown loglines by postscreen'
			@warnings                = prometheus.counter :warnings_total,           docstring: 'A counter of any warnings'
			@psc_cache_update_delay  = prometheus.summary :psc_cache_update_delay_total,        docstring: 'A counter of PSC cache update delays by file', labels: %i[file]
			@curr_unavailable        = prometheus.counter :service_currently_unavailable_total, docstring: 'A counter for rejected mails, because service currently unavailable - so greylisted.'
			@dnsblog_reply_timeout   = prometheus.counter :dnsblog_reply_timeout_total,         docstring: 'Total timedout requests for dnsblog'
			@data_without_valid_rcpt = prometheus.counter :data_without_valid_rcpt_total,       docstring: 'A counter of DATA without valid RCPT events'
		end

		def collect entry
			#STDERR.puts "postscreen: #{entry.message}"
			case entry.message
			when /\ACONNECT from / then @connect_from.increment
			when /\AWHITELISTED / then @whitelisted.increment
			when /\APASS OLD / then @pass_old.increment
			when /\APASS NEW / then @pass_new.increment
			when /\ADISCONNECT / then @disconnect.increment
			when /\APREGREET / then @pregreet.increment
			when /\ABDAT / then @bdat.increment
			when /\AHANGUP / then @hangup.increment
			when /\ADNSBL rank / then @dnsbl.increment
			when /\ABARE NEWLINE / then @bare_newline.increment
			when /\ACOMMAND PIPELINING / then @command_pipelining.increment
			when /\ACOMMAND TIME LIMIT / then @command_time_limit.increment
			when /\ADATA without valid RCPT / then @data_without_valid_rcpt.increment
			when /\Acache / then @cache.collect entry
			when /\ANOQUEUE: (.*)/
				case msg = $1
				when /\Areject: RCPT from [^ ]+: 450 4.3.2 Service currently unavailable; /
					@curr_unavailable.increment
				else
					@noqueue.collect entry
				end
			when /\Awarning: (.*)/
				@warnings.increment
				case $1
				when /\Apsc_cache_update: ([^ ]+) update average delay is ([^ ]+)/
					@psc_cache_update_delay.observe $2.to_f, labels: {file: $1}
				when /\Adnsblog reply timeout /
					@dnsblog_reply_timeout.increment
				when /\Agetpeername: Transport endpoint is not connected -- dropping this connection/
				else
					STDERR.puts "# postscreen warnings: #{entry.message}"
				end
			else
				STDERR.puts "# postscreen: #{entry.message}"
				@unknown.increment
			end
		end
	end

	def self.tls_posibilities
		%w[Trusted Untrusted Anonymous].each do |trust|
			%w[TLSv1.2 TLSv1.3].each do |tls|
				%w[TLS_AES_128_GCM_SHA256 TLS_AES_256_GCM_SHA384 ECDHE-RSA-AES128-GCM-SHA256 ECDHE-RSA-AES256-GCM-SHA384].each do |cipher|
					yield trust, tls, cipher
				end
			end
		end
	end

	class Smtp
		def initialize store, prometheus
			@store = store
			@connection_refused   = prometheus.counter :connection_refused_total,   docstring: 'A counter of refused connections on smtp'
			@connection_timed_out = prometheus.counter :connection_timed_out_total, docstring: 'A counter of timed out connections on smtp'
			@tls                  = prometheus.counter :tls_total,                  docstring: 'A counter of TLS connections on smtp with TLS-version and cipher', labels: %i[trust tls cipher]
			Collector::Postfix.tls_posibilities {|t, s, c| @tls.increment by: 0, labels: {trust: t, tls: s, cipher: c} }
			@status               = prometheus.histogram :status,             docstring: 'A histogram of message status by status', labels: %i[status]
			@sent                 = prometheus.counter :sent_total,           docstring: 'A counter of sent messages by smtp'
			@deferred             = prometheus.counter :deferred_total,       docstring: 'A counter of deferred messages by smtp'
			@bounced              = prometheus.counter :bounced_total,        docstring: 'A counter of bounced messages by smtp'
			@deliverable          = prometheus.counter :deliverable_total,    docstring: 'A counter of deliverable messages by smtp'
			@undeliverable        = prometheus.counter :undeliverable_total,  docstring: 'A counter of undeliverable messages by smtp'
			@status_unknown       = prometheus.counter :status_unknown_total, docstring: 'A counter of unknown status by smtp'
			@unknown              = prometheus.counter :unknown_total,        docstring: 'A counter of unknown loglines by smtp'
		end

		def collect entry
			#STDERR.puts "smtp: #{entry.message}"
			case entry.message
			when /\Aconnect to /
				case entry.message
				when / Connection refused\z/ then @connection_refused.increment
				when / Connection timed out\z/ then @connection_timed_out.increment
				else
					STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier} connect to: #{entry.message}"
				end
			when /\A([^ ]+) TLS connection established to .* ([^ ]+) with cipher ([^ ]+)/
				@tls.increment labels: {trust: $1, tls: $2, cipher: $3}
			when /\A\w+: .* delay=([0-9.]+),.*status=([^ ]+)/
				# postfix@-.service: postfix/smtp/smtp 4KZ0KY5Wx4z4Mn: to=<wegmann@psi.co.at>, relay=mail.psi.co.at[81.223.32.197]:25, delay=0.76, delays=0.2/0/0.35/0.21, dsn=2.0.0, status=sent (250 2.0.0 Ok: queued as 710F7A0263)
				delay, status = $1.to_f, $2.downcase
				@status.observe delay, labels: {status: status}
				case status
				when 'sent' then @sent.increment
				when 'deferred' then @deferred.increment
				when 'bounced' then @bounced.increment
				when 'deliverable' then @deliverable.increment
				when 'undeliverable' then @undeliverable.increment
				else
					STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier} status: #{entry.message}"
					@status_unknown.increment
				end
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier}: #{entry.message}"
				@unknown.increment
			end
		end
	end

	class Smtpd
		def initialize store, prometheus
			@store = store
			@noqueue                    = Noqueue.new store, prometheus.prefix_proxy( :noqueue)
			@connect_from               = prometheus.counter :connect_from_total, docstring: 'A counter of connections to smtpd', labels: %i[from_unknown]
			%w[0 1].each {|x| @connect_from.increment by: 0, labels: {from_unknown: x} }
			@tls                        = prometheus.counter :tls_total, docstring: 'A counter of TLS connections to smtpd with TLS-version and cipher', labels: %i[trust tls cipher]
			Collector::Postfix.tls_posibilities {|t, s, c| @tls.increment by: 0, labels: {trust: t, tls: s, cipher: c} }
			@disconnect_from            = prometheus.counter :disconnect_from_total, docstring: 'A counter of "disconnect from" to smtpd'
			@disconnect_from_events     = prometheus.counter :disconnect_from_event_total, docstring: 'A counter of events while connection-lifetime (auth, starttls, mail, rcpt, data, commands, ...) from disconnections', labels: %i[event]
			%w[auth mail rcpt data commands starttls ehlo quit].each {|e| @disconnect_from_events.increment by: 0, labels: {event: e} }
			@concurrenty_limit_exceeded = prometheus.counter :concurrenty_limit_exceeded_total, docstring: 'A counter of concurrenty limit exceeded connections to smtpd'
			@timeout                    = prometheus.counter :timeout_connection_total, docstring: 'A counter of timedout connections to smtpd', labels: %i[after]
			@lost_connection            = prometheus.counter :lost_connection_total, docstring: 'A counter of lost connections to smtpd', labels: %i[after]
			@accepted                   = prometheus.counter :accepted_total, docstring: 'A counter of accepted messages to smtpd'
			@unknown                    = prometheus.counter :unknown_total, docstring: 'A counter of unknown loglines by smtpd'
			@sasl_auth_failed           = prometheus.counter :sasl_auth_failed_total, docstring: 'A counter of failed SASL authentication by method', labels: %i[method]
			@non_smtp_command           = prometheus.counter :non_smtp_command_total, docstring: 'A counter of Non-SMTP-commands (ex. was a HTTP GET / HTTP/1.1)'
			@tls_lib_problem            = prometheus.counter :tls_lib_problem_total, docstring: 'A counter of TLS libreary problems (ex. unsupported protocol'
			@ssl_error                  = prometheus.counter :ssl_error_total, docstring: 'A counter of any SSL_accept errors by error', labels: %i[error]
			@warnings                   = prometheus.counter :warnings_total, docstring: 'A counter of any warnings'
			%w[].each {|m| @sasl_auth_failed.increment by: 0, labels: {method: m} }
			@hostname_not_resolved_to_address = prometheus.counter :hostname_not_resolved_to_address_total, docstring: 'A counter of hostnames, which cannot be resolved to there IP'
		end

		def collect entry
			#STDERR.puts "smtpd: #{entry.message}"
			case entry.message
			when /\Aconnect from unknown/
				@connect_from.increment labels: {from_unknown: 1}
			when /\Aconnect from /
				@connect_from.increment labels: {from_unknown: 0}
			when /\A([^ ]+) TLS connection established from .*: ([^ ]+) with cipher ([^ ]+) /
				@tls.increment labels: {trust: $1, tls: $2, cipher: $3}
			when /\ANOQUEUE: /
				@noqueue.collect entry
			when /\Adisconnect from ([^ ]+) (.*)/
				@disconnect_from.increment
				# ehlo=2 starttls=1 auth=1 mail=1 rcpt=1 data=1 commands=8
				$2.split( ' ').each do |x|
					case x
					when /(\w+)=(\d+)/
						@disconnect_from_events.increment by: $2.to_f, labels: {event: $1}
					else
						STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier} disconnect from: [#{x}] #{entry.message}"
					end
				end
			when /\Awarning: (.*)/
					@warnings.increment
				case $1
				when /\AConnection concurrency limit exceeded: /
					@concurrenty_limit_exceeded.increment
				when /\Ahostname ([^ ]+) does not resolve to address /
					@hostname_not_resolved_to_address.increment
				when /\A[^ ]+\[([^ ]+)\]: SASL ([^ ]+) authentication failed/
					@sasl_auth_failed.increment labels: {method: $1.downcase}
				when /\Anon-SMTP command from /
					@non_smtp_command.increment
				when /\ATLS library problem /
					@tls_lib_problem.increment
				else
					STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier} wanring: #{entry.message}"
				end
			when /\ASSL_accept error from [^ ]+: (-?\d)/
				@ssl_error.increment labels: {error: $1.to_i}
			when /\Atimeout after ([^ ]+) from /
				@timeout.increment labels: {after: $1}
			when /\Alost connection after ([^ ]+) from /
				@lost_connection.increment labels: {after: $1}
			when /\A\w{8,15}: client=/ # sasl_method=
				@accepted.increment
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier}: #{entry.message}"
				@unknown.increment
			end
		end
	end

	class Tlsproxy
		def initialize store, prometheus
			@store = store
			@connect       = prometheus.counter :connect_total,    docstring: 'A counter of COUNNECT from tlsproxy'
			@disconnect    = prometheus.counter :disconnect_total, docstring: 'A counter of DISCOUNNECT from tlsproxy'
			@tls           = prometheus.counter :tls_total,        docstring: 'A counter of TLS connections to smtpd with TLS-version and cipher', labels: %i[trust tls cipher]
			Collector::Postfix.tls_posibilities {|t, s, c| @tls.increment by: 0, labels: {trust: t, tls: s, cipher: c} }
		end

		def collect entry
			case entry.message
			when /\ADISCONNECT / then @disconnect.increment
			when /\ACONNECT / then @connect.increment
			when /\A([^ ]+) TLS connection established from .*: ([^ ]+) with cipher ([^ ]+) /
				@tls.increment labels: {trust: $1, tls: $2, cipher: $3}
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier}: #{entry.message}"
			end
		end
	end

	class Bounce
		def initialize store, prometheus
			@store = store
			@non_delivery = prometheus.counter :sender_non_delivery_notification, docstring: 'A counter of notifications to sender because mail cannot deliveried'
		end

		def collect entry
			case entry.message
			when /\A([^ ]+): sender non-delivery notification: (.+)/
				# postfix@-.service: postfix/bounce/bounce 4L3cN05mX6zfB: sender non-delivery notification: 4L3cN06Qpkz4Fc
				@non_delivery.increment
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier}: #{entry.message}"
			end
		end
	end

	class SCache
		def initialize store, prometheus
			@store = store
			@start                        = prometheus.gauge :start,                        docstring: 'Start timestamp of SCache statistics'
			@domain_lookup_hits           = prometheus.counter :domain_lookup_hits_total,   docstring: 'Count of hits for domain lookups of SCache'
			@domain_lookup_miss           = prometheus.counter :domain_lookup_miss_total,   docstring: 'Count of misses for domain lookups of SCache'
			@domain_lookup_success_rate   = prometheus.gauge :domain_lookup_success_rate,   docstring: 'Success rate of domain lookups of SCache'
			@max_simultaneaus_domains     = prometheus.gauge :max_simultaneaus_domains,     docstring: 'Max simultaneaus connections Domains of SCache'
			@max_simultaneaus_addresses   = prometheus.gauge :max_simultaneaus_addresses,   docstring: 'Max simultaneaus connections Addresses of SCache'
			@max_simultaneaus_connections = prometheus.gauge :max_simultaneaus_connections, docstring: 'Max simultaneaus connections of SCache'
		end

		def collect entry
			case entry.message
			when /\Astatistics: start interval (.*)/
				# postfix@-.service: postfix/scache/scache statistics: start interval Apr 13 10:58:06
				@start.set Time.parse( $1).to_f
			when /\Astatistics: domain lookup hits=(\d+) miss=(\d+) success=(\d+)%/
				# postfix@-.service: postfix/scache/scache statistics: domain lookup hits=2 miss=4 success=33%
				@domain_lookup_hits.increment by: $1.to_f
				@domain_lookup_miss.increment by: $2.to_f
				@domain_lookup_success_rate.set $3.to_f/100
			when /\Astatistics: max simultaneous domains=(\d+) addresses=(\d+) connection=(\d+)/
				# postfix@-.service: postfix/scache/scache statistics: max simultaneous domains=1 addresses=1 connection=4
				@max_simultaneaus_domains.set $1.to_f
				@max_simultaneaus_addresses.set $2.to_f
				@max_simultaneaus_connections.set $3.to_f
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier}: #{entry.message}"
			end
		end
	end

	class Verify
		def initialize store, prometheus
			@store = store
			@cache = Cache.new store, prometheus.prefix_proxy( :cache)
		end

		def collect entry
			case entry.message
			when /\Acache / then @cache.collect entry
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier}: #{entry.message}"
			end
		end
	end

	def initialize store, prometheus
		@store = store
		@postscreen = Postscreen.new store, prometheus.prefix_proxy( :postscreen)
		@smtp       = Smtp.new       store, prometheus.prefix_proxy( :smtp)
		@smtpd      = Smtpd.new      store, prometheus.prefix_proxy( :smtpd)
		@submission = Smtpd.new      store, prometheus.prefix_proxy( :submission)
		@tlsproxy   = Tlsproxy.new   store, prometheus.prefix_proxy( :tlsproxy)
		@scache     = SCache.new     store, prometheus.prefix_proxy( :scache)
		@bounce     = Bounce.new     store, prometheus.prefix_proxy( :bounce)
		@verify     = Verify.new     store, prometheus.prefix_proxy( :verify)
		@qmgr       = prometheus.counter :qmgr_total,     docstring: 'A counter of qmgr actions'
		@cleanup    = prometheus.counter :cleanup_total,  docstring: 'A counter of cleanup actions'
		@lmtp       = prometheus.counter :lmtp_total,     docstring: 'A counter of ltmp actions'
		@pickup     = prometheus.counter :pickup_total,   docstring: 'A counter of pickup actions'
		@dnsblog    = prometheus.counter :dnsblog_total,  docstring: 'A counter for DNS-Blacklisted IP by DNSBL', labels: %i[dnsbl]
		@spf_fail   = prometheus.counter :spf_fail_total, docstring: 'A counter of policyd-SPF failed SPF'
		@spf        = prometheus.counter :spf_total,      docstring: 'A counter of prepended SPF header-lines with state', labels: %i[status]
		%w[pass none].each {|s| @spf.increment by: 0, labels: {status: s} }
		@anvil_max_connection_rate_per_minute = prometheus.gauge :anvil_max_connection_per_minute_rate, docstring: "Rate of max connections per minute to listener", labels: %i{listener}
		@anvil_max_connection_count           = prometheus.gauge :anvil_max_connection_count,           docstring: "Count of max connections to listener", labels: %i{listener}
		@anvil_max_cache_size                 = prometheus.gauge :anvil_max_cache_size,                 docstring: "Current max cache size"
	end

	def collect entry
		#STDERR.puts "postfix: #{entry.syslog_identifier}: #{entry.message}"
		case entry.syslog_identifier
		when 'postfix/tlsproxy',   'postfix/tlsproxy/tlsproxy' then @tlsproxy.collect entry
		when 'postfix/postscreen', 'postfix/smtp/postscreen'   then @postscreen.collect entry
		when 'postfix/smtp',       'postfix/smtp/smtp'         then @smtp.collect entry
		when 'postfix/smtpd',      'postfix/smtpd/smtpd'       then @smtpd.collect entry
		when                       'postfix/submission/smtpd'  then @submission.collect entry
		when 'postfix/bounce',     'postfix/bounce/bounce'     then @bounce.collect entry
		when 'postifx/verify',     'postfix/verify/verify'     then @verify.collect entry
		when 'postfix/cleanup',    'postfix/cleanup/cleanup'   then @cleanup.increment
		when 'postfix/qmgr',       'postfix/qmgr/qmgr'         then @qmgr.increment
		when 'postfix/lmtp',       'postfix/lmtp/lmtp'         then @lmtp.increment
		when 'postfix/pickup',     'postfix/pickup/pickup'     then @pickup.increment
		when 'postfix/scache',     'postfix/scache/scache'     then @scache.collect entry
		when 'postfix/dnsblog',    'postfix/dnsblog/dnsblog'
			case entry.message
			when /\Aaddr [^ ]+ listed by domain ([^ ]+) as /
				@dnsblog.increment labels: {dnsbl: $1.downcase}
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier}: #{entry.message}"
			end
		when 'postfix/anvil', 'postfix/anvil/anvil'
			case entry.message
			when /\Astatistics: max connection rate (\d+)\/60s for \((.+)\) at (.*)/
				@anvil_max_connection_rate_per_minute.set $1.to_i, labels: {listener: $2}
			when /\Astatistics: max connection count (\d+) for \((.+)\) at (.*)/
				@anvil_max_connection_count.set $1.to_i, labels: {listener: $2}
			when /\Astatistics: max cache size (\d+) at (.*)/
				@anvil_max_cache_size.set $1.to_i
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier}: #{entry.message}"
			end
		when 'policyd-spf'
			case entry.message
			when /\Aprepend Received-SPF: (\w+) /
				@spf.increment labels: {status: $1.downcase}
			when /\A[^ ]+ [^ ]+ Message rejected due to: SPF fail /
				# postfix@-.service policyd-spf: 550 5.7.23 Message rejected due to: SPF fail - not authorized.
				@spf_fail.increment
			else
				STDERR.puts "# #{entry._systemd_unit} #{entry.syslog_identifier}: #{entry.message}"
			end
		else
			STDERR.puts "# #{entry._systemd_unit}: #{entry.syslog_identifier} #{entry.message}"
		end
	end
end