pinboard

#! /bin/bash

PINBOARD_DIR="$HOME/.pinboard"
PINBOARD_CFG="$PINBOARD_DIR/config"

CURL_CMD="curl -s -f -G"
PID_FILE="${PINBOARD_DIR}/pid"
LAST_UPDATE_FILE="${PINBOARD_DIR}/last-update"
CUR_UPDATE_FILE="${PINBOARD_DIR}/cur-update" 
BOOKMARK_FILE="$HOME/.config/vimb/bookmark"
BOOKMARK_BACKUP_FILE="${PINBOARD_DIR}/bookmark_backup"
BOOKMARK_TMP="${PINBOARD_DIR}/bookmark_tmp"
CURL_TMP="${PINBOARD_DIR}/curl_tmp"

HTTPS_PREFIX="https://api.pinboard.in/v1"

#***
# Functions
#***

#---------------------------------------------------------------
function error() {
    echo -e "$1"
    local code="${2:-1}"
    exit "$code"
}


# $1 is the method to query upon, $2 is the file to direct the output, while all the subsequent arguments
# in the format 'name=value' are appended as data arguments to
# the query
#---------------------------------------------------------------
function pinboard_api() {
    local datastring= data=
    for data in "${@:3}"
    do
        # we need to escape the single quote..merr...
        datastring="$datastring --data-urlencode \$'${data//\'/\'}'"
    done
    eval $CURL_CMD$datastring $HTTPS_PREFIX$1$AUTH_TOKEN > $2
	local CURL_EXIT_CODE="$?"
	if [[ $CURL_EXIT_CODE != "0" ]] ; then
		error "Curl failed with exit code $CURL_EXIT_CODE"
	fi
}

#---------------------------------------------------------------
function verify_config() {
	if [[ ! -e "$PINBOARD_CFG" ]]; then
		error "Could not find $PINBOARD_CFG file! \nIt should contain two lines. Line 1 the username. Line 2 the API token. \nYou can create it manually, or use the \"login\" command."
	fi

	USER_NAME=`head -n1 $PINBOARD_CFG`
	API_TOKEN=`tail -n1 $PINBOARD_CFG`
	AUTH_TOKEN="?auth_token=$USER_NAME:$API_TOKEN"
}

#***
# Commands
#***

#---------------------------------------------------------------
function help_cmd() {
	cat << END 
    List of available commands:
    login               -- save the authentication token needed for pinboard
    synchronize         -- synchronize the cloud and local bookmarks
    help                -- show this help message
END
}

# Printing out the bookmark information
#---------------------------------------------------------------
function print_bookmark() {
    echo -n "$1 ($2) <$3>"
}

# This inserts the bookmark to the tmp bookmark file
# $1: href
# $2: description
# $3: tag (space delimited)
#---------------------------------------------------------------
function insert_vimb_bookmark() {
    echo "Inserting into local vimb bookmark storage... : `print_bookmark "$1" "$2" "$3"`"
    echo -e "$1\t$2\t$3" >> "$BOOKMARK_TMP"
}

# $1: the bookmark line passed from a vimb bookmark file
#---------------------------------------------------------------
function insert_pinboard_bookmark_from_vimb_format() {
    # obtain the attributes and insert into the cloud
    local url="`echo "$1" | cut -d$'\t' -f1`"
    local desc="`echo "$1" | cut -d$'\t' -f2`"
    local tags="`echo "$1" | cut -d$'\t' -f3`"
    insert_pinboard_bookmark "$url" "${desc:-$tags}" "$tags"
}

# $1: the bookmark line passed from a vimb bookmark file
#---------------------------------------------------------------
function delete_pinboard_bookmark_from_vimb_format() {
    delete_pinboard_bookmark "`echo "$1" | cut -d$'\t' -f1`"
}

# $1: href
# $2: description
# $3: tag (space delimited)
function insert_pinboard_bookmark() {
    echo "Inserting into pinboard cloud... : `print_bookmark "$1" "$2" "$3"`"
    pinboard_api '/posts/add' "$CURL_TMP" "url=$1" "description=$2" "tags=$3"
    # check for the result
    if ! grep 'done' "$CURL_TMP" > /dev/null 2>&1; then
        error "Pinboard bookmark insertion failed."
    fi
}

# $1: href
function delete_pinboard_bookmark() {
    echo "Deleting from pinboard cloud... : $1"
    pinboard_api '/posts/delete' "$CURL_TMP" "url=$1" 
    # check for the result
    if ! grep 'done' "$CURL_TMP" > /dev/null 2>&1; then
        error "Pinboard bookmark deletion failed."
    fi
}

# This will compare the current update with the last update and
# return true if there's new update
#---------------------------------------------------------------
function pinboard_has_update() {
	# See if we need to do an update at all
	echo "Retrieving current pinboard update time..."
	pinboard_api "/posts/update" "$CUR_UPDATE_FILE"
	if [[ ! -e "$LAST_UPDATE_FILE" ]]; then
		echo "$LAST_UPDATE_FILE does not exist..."
		return 0
	else
		# Compare current update with last update
		echo "Comparing last update with current update..."
		diff "$CUR_UPDATE_FILE" "$LAST_UPDATE_FILE"
		if [[ ! "$?" == "0" ]]; then 
			return 0
		fi ;
	fi
    return 1
}

#---------------------------------------------------------------
function synchronize_cmd() {
    local to_update_pinboard=false to_update_local=false
    echo "######## Checking changes on the server ########"
    verify_config
    pinboard_has_update && to_update_pinboard=true
    echo "######## Starting local-to-cloud synchronization ########"
    # first compare the two bookmarks file to see if there are any changes
    if [[ -e "$BOOKMARK_BACKUP_FILE" ]]; then
        echo "Detecting changes to the bookmark file..."
        local changes="`diff "$BOOKMARK_BACKUP_FILE" "$BOOKMARK_FILE"`" 
        if [ -n "$changes" ]; then
            to_update_local=true
            # we need to grep for all deletions 
            echo "$changes" | grep '^<' | while read line; do
                delete_pinboard_bookmark_from_vimb_format "${line#< }" 
            done
            # have to exit the script if error occurred
            (( $? != 0 )) && exit "$?"
            echo "$changes" | grep '^>' | while read line; do
                insert_pinboard_bookmark_from_vimb_format "${line#> }" 
            done
            (( $? != 0 )) && exit "$?"
        else
            echo "No local-to-cloud synchronization required. Local bookmark storage is in sync with pinboard account."
        fi
    else
        to_update_local=true
        echo "Bookmark file has not been backed up before. Trying to insert all entries..."
        while read line; do
            insert_pinboard_bookmark_from_vimb_format "$line"
        done < "$BOOKMARK_FILE"
    fi

    if $to_update_local; then
        # we have updated the server so we should refresh the update time
        echo "Refreshing the last update time..."
        pinboard_api "/posts/update" "$CUR_UPDATE_FILE"
    fi

    echo "######## Starting cloud-to-local synchronization ########"
    if $to_update_pinboard; then
        echo "Retrieving bookmarks..."
        pinboard_api "/posts/all" "$CURL_TMP"
        # we need to convert the format into vimb's format
        xml sel -t -m '/posts/post' -c '.' -n "$CURL_TMP" | while read line; do
            # retrieve the attributes
            local href="`echo "$line" | xml sel -t -v '/post/@href'`"
            local desc="`echo "$line" | xml sel -t -v '/post/@description'`"
            local tag="`echo "$line" | xml sel -t -v '/post/@tag'`"
            # just adding the bookmark to tmp file
            insert_vimb_bookmark "$href" "$desc" "$tag"
        done
        # move the tmp file to overwrite the old bookmark file
        # this might be dangerous if there're unsynced changes in the bookmark file 
        # but for the time being we'd assume that the bookmark file is already in sync with
        # the cloud
        echo "Overwriting the old bookmark file..."
        mv -f "$BOOKMARK_TMP" "$BOOKMARK_FILE"
    else
        echo "No cloud-to-local synchronization required. $BOOKMARK_FILE is current."
    fi

    # back up the bookmark file
    if $to_update_local || $to_update_pinboard; then
        echo "Backing up the current bookmark file..."
        cp -f "$BOOKMARK_FILE" "$BOOKMARK_BACKUP_FILE"
    fi

    echo "Moving current update time to last update time..."
    mv -f $CUR_UPDATE_FILE $LAST_UPDATE_FILE
    echo "Done."  
}

#---------------------------------------------------------------
function login_cmd() {
	if [[ ! -d "$PINBOARD_DIR" ]]; then
		mkdir "$PINBOARD_DIR"
	fi

	if [[ ! -d "$PINBOARD_DIR" ]]; then
		echo "$PINBOARD_DIR could not be made."
		exit 1
	fi

	echo "We will attempt to log into pinboard now."
	`which echo` -n "Please enter pinboard username: "
	local USER_NAME=`head -n 1`
	echo $USER_NAME > "$PINBOARD_CFG"

	$CURL_CMD -u $USER_NAME "$HTTPS_PREFIX/user/api_token" | tail -n 1 | sed 's/<[^>]*>//g' >> $PINBOARD_CFG
	local CURL_EXIT_CODE="$?"
	if [[ $CURL_EXIT_CODE != "0" ]]; then
		echo "Curl failed with exit code $CURL_EXIT_CODE"
		exit 1
	fi

	if [[ ! -e "$PINBOARD_CFG" ]]; then
		echo "$PINBOARD_CFG could not be made."
		exit 1
	else 
		chmod og-rw "$PINBOARD_CFG"
	fi

	echo "Created $PINBOARD_CFG."
	echo "Logged in!"
}

#***
# "Main"
#***

if [[ $# -lt 1 ]]; then
    error "Expected a command for the second argument. \nTry \"help\"."
fi

#***
# Process the second commands
#***
case "$1" in
    synchronize) 
        [ "PINBOARD$PPID" = "$LOCKRUNPID" ] || exec lockrun -qna PINBOARD /tmp/lockrun.pinboard "$0" "$@" || exit 1
        synchronize_cmd
        ;;
    login) 
        login_cmd
        ;;
    help) 
        help_cmd 
        ;;
    *)
        error "Unknown command $1. Try \"help\"." 2
esac

# exiting without any errors
exit 0