diff --git a/atom b/atom
index 9f6d926..97f0688 100755
--- a/atom
+++ b/atom
@@ -1,5 +1,42 @@
 #!/bin/bash
 
+## Define exit codes
+# General config errors [10-19]
+ELOAD=10
+EINTERVAL=11
+ENOCFG=19
+# Source cofig errors [20-29]
+# Destination config errors [30-49]
+EFORMAT=30
+ECHANNEL=31
+EFMTINVPARM=49
+
+# config structures
+declare -A			\
+	destinationchannels	\
+	destinationcopymime	\
+	destinationformat	\
+	destinationfrequency	\
+	destinationid		\
+	destinationpath		\
+	destinationquality	\
+	destinationrename	\
+	destinationrenamepath	\
+	destinationskipmime	\
+|| {
+	echo "Check your Bash version. You need >= 4.0" >&2
+	exit $EBASHVERS
+}
+
+declare -r				\
+	DOCDIR=./doc			\
+	SHAREDIR=./share
+declare -r				\
+	exampleconf=$DOCDIR/example.cfg	\
+	schema=$SHAREDIR/schema.sql	\
+					\
+	oldIFS="$IFS"
+
 #parse arguments
 OPTERR=0
 while getopts ':c:l:T:F:hD' opt
@@ -38,11 +75,528 @@ do
 done
 
 #parse config
+getConfigGeneral() {
+	case $key in
+		'max-load')
+			expr='^[0-9]*$'
+			if [[ $value =~ $expr ]]
+			then
+				maxload="$value"
+			else
+				echo "Invalid max-load value: $value" >&2
+				exit $ELOAD
+			fi
+			unset expr
+		;;
+		'load-interval')
+			expr='^[0-9]*$'
+			if [[ $value =~ $expr ]]
+			then
+				loadinterval="$value"
+			else
+				echo "Invalid load-interval value: $value" >&2
+				exit $EINTERVAL
+			fi
+			unset expr
+		;;
+		'temporary-directory')
+			tempdir="$value"
+		;;
+		'database')
+			database="$value"
+		;;
+		debug)
+			#unimplemented
+		;;
+	esac
+}
+
+getConfigSource() {
+	case "$key" in
+		'path')
+			sourcepath="$value"
+		;;
+		'id3charset')
+			sourceid3charset="$value"
+		;;
+	esac
+}
+
+getConfigDestination() {
+	case "$key" in
+		'path')
+			destinationpath["$destination"]="$value"
+		;;
+		'format')
+			case "$value" in
+				'mp3')
+					destinationformat["$destination"]=mp3
+				;;
+				'vorbis')
+					destinationformat["$destination"]=vorbis
+				;;
+				*)
+					echo "Unsupported destination format: $value" >2&
+					exit $EFORMAT
+				;;
+			esac
+		;;
+		'quality')
+			expr='^[0-9]*$'
+			if ! [[ $value =~ $expr ]]
+			then
+				echo "Invalid quality value: $value" >&2
+				exit $EQUALITY
+			fi
+			unset expr
+			case "${destinationformat["$destination"]}" in
+				'vorbis')
+					destinationquality["$destination"]="$value"
+				;;
+				*)
+					echo "$Invalid parameter \"$key\" for format \"${destinationformat["$destination"]}\"" >&2
+					exit $EFMTINVPARM
+				;;
+			esac
+		;;
+		'bitrate')
+			expr='^[0-9]*$'
+			if ! [[ $value =~ $expr ]]
+			then
+				echo "Invalid bitrate value: $value" >&2
+				exit $EQUALITY
+			fi
+			unset expr
+			case "${destinationformat["$destination"]}" in
+				'mp3')
+					destinationquality["$destination"]="$value"
+				;;
+				*)
+					echo "$Invalid parameter \"$key\" for format \"${destinationformat["$destination"]}\"" >&2
+					exit $EFMTINVPARM
+				;;
+			esac
+		;;
+		'channels')
+			expr='^[0-9]*$'
+			if ! [[ $value =~ $expr ]]
+			then
+				echo "Invalid channel count: $value" >&2
+				exit $ECHANNEL
+			fi
+			unset expr
+			destinationchannels["$destination"]=$value
+		;;
+		'frequency')
+			expr='^[0-9]*$'
+			if ! [[ $value =~ $expr ]]
+			then
+				echo "Invalid frequency value: $value" >&2
+				exit $ECHANNEL
+			fi
+			unset expr
+			destinationfrequency["$destination"]=$value
+		;;
+		'rename')
+			case "$value" in
+				*/*)
+					destinationrenamepath["$destination"]="${value%/*}"
+				;;
+			esac
+			destinationrename["$destination"]="${value##*/}"
+		;;
+		'skip_mime-type')
+			destinationskipmime[$destination]="${destinationskipmime[$destination]:+${destinationskipmime[$destination]}|}$value"
+		;;
+		'copy_mime-type')
+			destinationcopymime[$destination]="${destinationcopymime[$destination]:+${destinationcopymime[$destination]}|}$value"
+		;;
+	esac
+}
+getConfig() {
+	while read key value
+	do
+		case $key in
+			'#'*)
+				#comment
+			;;
+			'')
+				#empty line
+			;;
+			'[general]')
+				context=General
+			;;
+			'[source]')
+				context=Source
+			;;
+			\[*\])
+				context=Destination
+				destination="${key#[}"
+				destination="${destination%]}"
+			;;
+			*)
+				getConfig$context
+			;;
+		esac
+	done < ~/.atom/atom.cfg
+}
 
 #check sanity
 
+openDatabase() {
+	if [ ! -d "$tempdir" ]
+	then
+		mkdir -p "$tempdir"
+	fi
+	mkfifo "$tempdir"/sqlite.{in,out}
+	if [ ! -f "$database" ]
+	then
+		if [ ! -d "${database%/*}" ]
+		then
+			mkdir -p "${database%/*}"
+		fi
+		sqlite3 "$database" < $schema
+	fi
+	sqlite3 "$database"		\
+		< "$tempdir/sqlite.in"	\
+		> "$tempdir/sqlite.out"	&
+	exec 3> "$tempdir"/sqlite.in
+	exec 4< "$tempdir"/sqlite.out
+}
+
+closeDatabase() {
+	exec 3>&-
+	exec 4<&-
+	rm "$tempdir"/sqlite.{in,out}
+}
+
+Select() {
+#Select table [col1 [col2 [..]]] <	WHERE_key WHERE_operator WHERE_value
+#					[WHERE_key WHERE_operator WHERE_value
+#					[…]]
+	local			\
+		table="$1"	\
+		col		\
+		columns		\
+		operator	\
+		results		\
+		where_statement
+	shift
+	for col
+	do
+		(( ${#columns} )) && columns+=','
+		columns+="$col"
+	done
+	while read key operator value
+	do
+		(( ${#where_statement} )) && where_statement+=( "AND" )
+		where_statement+=( "$key $operator "'"'"${value//\"/\\\"}"'"' )
+	done
+	echo	"SELECT IFNULL("				\
+			"(SELECT $columns FROM $table"		\
+				"WHERE ${where_statement[@]})"	\
+			",'SQL::Select:not found'"		\
+		");" >&3
+	read -u 4 results
+	if ! [[ $results == "SQL::Select:not found" ]]
+	then
+		echo "$results"
+	else
+		return 1
+	fi
+}
+Insert() {
+#Insert table [no_id] <	key value
+#			[key value
+#			[…]]
+	local			\
+		table="$1"	\
+		no_id="${2:-0}"	\
+		insert_keys	\
+		insert_values	\
+		results
+	while read key value
+	do
+		(( ${#insert_keys} )) && insert_keys+=","
+		insert_keys+='`'"$key"'`'
+		(( ${#insert_values} )) && insert_values+=","
+		if [[ $value == NULL ]]
+		then
+			insert_values+="NULL"
+		else
+			insert_values+='"'"${value//\"/\\\"}"'"'
+		fi
+	done
+	echo	"INSERT INTO $table"				\
+				"( $insert_keys )"		\
+			"VALUES"				\
+				"( $insert_values );" >&3
+	(( no_id )) || {
+		echo 'SELECT LAST_INSERT_ROWID();' >&3
+		read -u 4 results
+		echo "$results"
+	}
+}
+Update(){
+#Update table set_key set_value [set_key set_value […]] <	where_key where_operator where_value
+#								[where_key where_operator where_value
+#								[…]]
+	local			\
+		table="$1"	\
+		key		\
+		argument	\
+		operator	\
+		value		\
+		set_statement	\
+		where_keys	\
+		where_values	\
+		what		\
+		where_statement	\
+		results
+	shift
+	what=key
+	for argument
+	do
+		case $what in
+			key)
+				set_statement="${set_statement:+${set_statement},}\`$argument\`"
+				what=value
+			;;
+			value)
+				set_statement="${set_statement}="'"'"${argument//\"/\\\"}"'"'
+				what=key
+			;;
+		esac
+	done
+	while read key operator value
+	do
+		(( ${#where_statement} )) && where_statement+=( "AND" )
+		if [[ $value == NULL ]]
+		then
+			where_statement+=( "$key is NULL" )
+		else
+			where_statement+=( "$key $operator "'"'"${value//\"/\\\"}"'"' )
+		fi
+	done
+	echo	"UPDATE '$table' SET"		\
+			"$set_statement"	\
+		"WHERE"				\
+			"${where_statement[@]}"	\
+		";" >&3
+}
+InsertIfUnset() {
+#InsertIfUnset table [no_id] < key value \n key value
+	local			\
+		table="$1"	\
+		no_id="${2:-0}"	\
+		column		\
+		key		\
+		keys		\
+		results		\
+		value		\
+		values
+	while read key value
+	do
+		keys+=( "$key" )
+		values+=( "$value" )
+	done
+	if (( no_id ))
+	then
+		column="${keys[0]}"
+	else
+		column='id'
+	fi
+	if ! results=$(
+		Select "$table" "$column" < <(
+			for key in ${!keys[@]}
+			do
+				echo "${keys[$key]}" = "${values[$key]}"
+			done
+		)
+	)
+	then
+		results=$(
+			Insert "$table" < <(
+				for key in ${!keys[@]}
+				do
+					echo "${keys[$key]}" "${values[$key]}"
+				done
+			)
+		)
+	fi
+	echo "$results"
+}
+InsertOrUpdate() {
+#InsertOrUpdate table set_key set_value [set_key set_value […]] <	where_key where_value
+#									[where_key where_value
+#									[…]]
+	local			\
+		table="$1"	\
+		argument	\
+		key		\
+		keys		\
+		set_keys	\
+		set_values	\
+		value		\
+		values		\
+		what		\
+		results
+	shift
+	what=key
+	for argument
+	do
+		case $what in
+			key)
+				set_keys+=( "$argument" )
+				what=value
+			;;
+			value)
+				set_values+=( "$argument" )
+				what=key
+			;;
+		esac
+	done
+	while read key value
+	do
+		keys+=( "$key" )
+		values+=( "$value" )
+	done
+	if results=$(
+		Select "$table" id < <(
+			for key in ${!keys[@]}
+			do
+				echo "${keys[$key]}" = "${values[$key]}"
+			done
+		)
+	)
+	then
+		Update "$table" "$@" < <(
+			for key in ${!keys[@]}
+			do
+				echo "${keys[$key]}" = "${values[$key]}"
+			done
+		)
+	else
+		results=$(
+			Insert "$table" < <(
+				for key in ${!set_keys[@]}
+				do
+					echo "${set_keys[$key]}" "${set_values[$key]}"
+				done
+				for key in ${!keys[@]}
+				do
+					echo "${keys[$key]}" "${values[$key]}"
+				done
+			)
+		)
+	fi
+	echo "$results"
+}
+Delete() {
+#Delete table <	where_key where_operator where_value
+#		[where_key where_operator where_value
+#		[…]]
+	local			\
+		table="$1"	\
+		key		\
+		operator	\
+		value		\
+		where_statement	\
+		results
+	while read key operator value
+	do
+		(( ${#where_statement} )) && where_statement+=( "AND" )
+		if [[ $value == NULL ]]
+		then
+			where_statement+=( "$key is NULL" )
+		else
+			where_statement+=( "$key $operator "'"'"${value//\"/\\\"}"'"' )
+		fi
+	done
+	echo "DELETE from $table WHERE ${where_statement[@]};" >&3
+}
+
+createDestinations() {
+	for destination in ${!destinationpath[@]}
+	do
+		if ! [ -d "${destinationpath["$destination"]}" ]
+		then
+			if ! mkdir -p "${destinationpath["$destination"]}"
+			then
+				echo "$destination: Could not create ${destinationpath["$destination"]}!"
+				exit $EINVDEST
+			fi
+		fi
+		destinationid["$destination"]=$(
+			InsertIfUnset destinations <<<"name $destination"
+		)
+	done
+}
+
 getFiles() {
-	:
+	scantime=$(date +%s)
+	# We probably have thousands of files, don't waste time on disk writes
+	echo 'BEGIN TRANSACTION;' >&3
+	while read time size filename
+	do
+		sourcefileid=$(
+			InsertOrUpdate source_files	\
+				last_change ${time%.*}	\
+				size $size		\
+				last_seen $scantime	\
+			<<-EOWhere
+				filename $filename
+			EOWhere
+		)
+		case $(( ++count % 4 )) in
+			0) echo -ne '\r|' ;;
+			1) echo -ne '\r/' ;;
+			2) echo -en '\r-' ;;
+			3) echo -ne '\r\\' ;;
+		esac
+	done < <(
+		find "$sourcepath" -type f -printf "%T@ %s %P\n"
+	)
+	echo 'COMMIT;' >&3
+	echo -e "\r$count files found."
+}
+
+updateMimes() {
+	Update mime_actions action 1 <<<"action != 1"
+	for destination in ${!destinationskipmime[@]}
+	do
+		IFS='|'
+		for mime_type in ${destinationskipmime["$destination"]}
+		do
+			IFS="$oldIFS"
+			Update mime_type_actions action 0 >/dev/null < <(
+				cat <<-EOWhere
+					destination_id = ${destinationid["$destination"]}
+					mime_text LIKE ${mime_type//*/%}
+				EOWhere
+			)
+		done
+	done
+	for destination in ${!destinationcopymime[@]}
+	do
+		IFS='|'
+		for mime_type in ${destinationcopymime["$destination"]}
+		do
+			IFS="$oldIFS"
+			Update mime_type_actions action 2 >/dev/null < <(
+				cat <<-EOWhere
+					destination_id = ${destinationid["$destination"]}
+					mime_text LIKE ${mime_type//*/%}
+				EOWhere
+			)
+		done
+	done
+}
+
+removeObsoleteFiles() {
+	Delete source_files <<-EOWhere
+		last_seen < $scantime
+	EOWhere
 }
 
 getType() {
@@ -127,4 +681,61 @@ transcodeLauncher() {
 
 #UI
 
+if [ ! -f ~/.atom/atom.cfg ]
+then
+	if [ ! -d ~/.atom ]
+	then
+		mkdir -p ~/.atom
+	fi
+	sed "s:%HOME%:$HOME:" "$exampleconf" > ~/.atom/atom.cfg
+	cat >&2 <<-EOCfgNotice
+	No configuration file found!
+	An example file has been created as ~/.atom/atom.cfg.
+	You should change it to your likings using you favorite editor.
+
+	Bailing out.
+	EOCfgNotice
+	exit $ENOCFG
+fi
+getConfig
+{
+cat <<EOF
+General|Load|$maxload
+|Load Interval|$loadinterval
+|Temp Dir|$tempdir
+|Database|$database
+|Debug|$debug
+Source|Path|$sourcepath
+|ID3 Charset|$sourceid3charset
+EOF
+for destination in ${!destinationpath[@]}
+do
+cat <<EOF
+$destination|Path|${destinationpath[$destination]}
+|Format|${destinationformat[$destination]}
+|Quality|${destinationquality[$destination]}
+|Channels|${destinationchannels[$destination]}
+|Frequency|${destinationfrequency[$destination]}
+|Path Change|${destinationrenamepath[$destination]}
+|File Rename|${destinationrename[$destination]}
+EOF
+echo "|Skipped mime-type|${destinationskipmime[$destination]//\|/
+|Skipped mime-type|}"
+echo "|Copied mime-type|${destinationcopymime[$destination]//\|/
+|Copied mime-type|}"
+done
+}|column -t -s'|' -n
+
+openDatabase
+
+createDestinations
+
+getFiles
+
+updateMimes
+
+removeObsoleteFiles
+
+closeDatabase
+
 # vim:set ts=8 sw=8:
diff --git a/doc/example.cfg b/doc/example.cfg
new file mode 100644
index 0000000..3e9f5f3
--- /dev/null
+++ b/doc/example.cfg
@@ -0,0 +1,43 @@
+[general]
+max-load		6
+load-interval		30
+temporary-directory	%HOME%/.atom/tmp
+database		%HOME%/.atom/atom.db
+debug			0
+
+[source]
+path		/var/lib/mpd/music
+id3charset	iso-8859-15
+
+[Ogg]
+path		/mnt/Musique-OggQ2
+format		vorbis
+quality		1
+channels	2
+frequency	44100
+
+# you should not skip or copy application/octet-stream, they could be something
+# similar to "Audio file with ID3 version 2.4.0, unsynchronized frames"
+copy_mime-type	image/*
+copy_mime-type	text/*
+
+[MP3]
+path	/mnt/Musique-mp3.test
+format	mp3
+bitrate	96
+
+# rename file, path unchanged
+rename	%{track}--%{artist}-%{title}
+# change the whole filepath
+#rename	%{genre}/%{albumartist}/%{year}-%{album}/%{track}--%{artist}-%{title}
+skip_mime-type	image/*
+skip_mime-type	text/*
+
+[asterisk]
+path		/mnt/Musique-asterisk
+format		vorbis
+channels	1
+frequency	8000
+skip_mime-type	image/*
+skip_mime-type	text/*
+
diff --git a/share/schema.sql b/share/schema.sql
new file mode 100644
index 0000000..3562f1e
--- /dev/null
+++ b/share/schema.sql
@@ -0,0 +1,71 @@
+BEGIN TRANSACTION;
+CREATE TABLE source_files (
+	id		INTEGER PRIMARY KEY,
+	filename	TEXT	UNIQUE NOT NULL,
+	size		INTEGER NOT NULL,
+	hash		TEXT,
+	mime_type	INTEGER,
+	last_change	INTEGER NOT NULL DEFAULT (strftime('%s','now')),
+	last_seen	INTEGER	NOT NULL DEFAULT (strftime('%s','now')),
+	FOREIGN KEY	(mime_type)	REFERENCES mime_types(id)
+);
+CREATE TABLE destinations (
+	id		INTEGER PRIMARY KEY,
+	name		TEXT	UNIQUE NOT NULL
+);
+CREATE TABLE destination_files (
+	id		INTEGER PRIMARY KEY,
+	filename	TEXT,
+	last_change	INTEGER	NOT NULL DEFAULT 0,
+	source_file_id	INTEGER,
+	destination_id	INTEGER,
+	FOREIGN KEY	(source_file_id)	REFERENCES source_files(id),
+	FOREIGN KEY	(destination_id)	REFERENCES destinations(id)
+);
+CREATE TABLE mime_types (
+	id		INTEGER PRIMARY KEY,
+	mime_text	TEXT	UNIQUE NOT NULL
+);
+CREATE TABLE mime_actions (
+	id		INTEGER PRIMARY KEY,
+	mime_type	INTEGER,
+	destination_id	INTEGER,
+	action		INTEGER	DEFAULT 1,
+	FOREIGN KEY	(mime_type)	REFERENCES mime_types(id)
+	FOREIGN KEY	(destination_id)	REFERENCES destinations(id)
+);
+
+CREATE VIEW mime_type_actions AS
+	SELECT
+		mime_types.id,mime_types.mime_text,
+		mime_actions.destination_id,mime_actions.action
+	FROM mime_types INNER JOIN mime_actions
+		ON mime_actions.mime_type = mime_types.id;
+CREATE TRIGGER update_mime_actions INSTEAD OF UPDATE OF action ON mime_type_actions
+BEGIN
+	UPDATE mime_actions SET action=new.action WHERE mime_type=old.id;
+END;
+
+CREATE TRIGGER create_mime_actions AFTER INSERT ON mime_types
+BEGIN
+	INSERT INTO mime_actions (mime_type,destination_id)
+	SELECT mime_types.id,destinations.id
+	FROM mime_types INNER JOIN destinations
+	WHERE mime_types.id=new.id;
+END;
+
+CREATE INDEX sourcefiles_by_name ON source_files (filename,id);
+
+CREATE TRIGGER create_destinations AFTER INSERT ON source_files
+BEGIN
+	INSERT INTO destination_files (source_file_id,destination_id)
+		SELECT source_files.id,destinations.id FROM source_files
+	INNER JOIN destinations
+		WHERE source_files.id=new.id;
+END;
+CREATE TRIGGER delete_destinations_files AFTER DELETE ON source_files
+BEGIN
+	UPDATE destination_files SET source_file_id=NULL WHERE source_file_id=old.id;
+END;
+
+COMMIT;