urreg

#!/bin/sh

if [ "$1" = '--version' ] || [ "$1" = '-v' ]
then
    echo "URReg v1.0"
    exit 0
elif [ "$1" = '--help' ] || [ "$1" = '-h' ]
then
    printf 'usage: %s [OPTIONS]\n\n' "$0"
    echo "Options that must come first:"
    echo " -h, --help       Displays this help message and exits."
    echo " -v, --version    Displays the version number and exits."
    echo
    echo "Other options:"
    echo " -q, --quiet      Turns off messages sent to stdout."
    echo "     --verbose    Displays extra information for debugging."
    exit 0
fi

v=

while [ -n "$1" ]
do
    case "$1" in
        --verbose)
            set -x
            v=-v
            q=
            ;;

        -q|--quiet)
            set +x
            q=-q
            v=
            ;;

        *)
            printf "Unrecognized argument: %s\n" "$1"

    esac

    shift
done

COOKIE_JAR=COOKIES
LOG_FILE=LOG
CONFIRM_CRN=false

# I'm not sure why but for both curl and Ruby's Mechanize, but not for
# browsers, the SSL certificate for the registration pages is found invalid
# and can't be validated properly. It works with the check disabled but is
# less secure.

curl_args="-s $v -k -c $COOKIE_JAR -b $COOKIE_JAR"

> "$LOG_FILE"
> "$COOKIE_JAR"

log()
{
    msg="$(date +%s) [$(date)]"

    [ $# = 0 ] || msg="$msg $*"

    printf "%s\n" "$msg" >> "$LOG_FILE"
}

log 'URReg v0.0'

log "Using $COOKIE_JAR as the cookie jar"

log "\$curl_args = '$curl_args'"

log 'BEGIN'

id=
password=

crns=

ts="TS=$(date +%s)"

log "\$ts = '$ts'"

is_insecure()
{
    # Check if a file is accessible to other users
    if [ -n "$(find $1 -perm /066)" ]
    then
        log "is_insecure(): $1 => TRUE"
        return 0
    fi

    log "is_insecure(): $1 => FALSE"

    return 1
}

# TODO - Test this
make_secure()
{
    log "make_secure(): securing $1"
    chmod -066 "$1"
}

# get saved login info from ~/.netrc
parse_netrc()
{
    log 'parse_netrc(): BEGIN'

    regexid='/login/!d;s/.*login \("\(\([^"\]\|\\.\)*\)"\|\(\([^ \]\|\\.\)*\)\).*/\2\4/;s/\\\([^\\]\)/\1/g;s/\\$//g;s/\\\\/\\/g'
    regexpass='/password/!d;s/.*password \("\(\([^"\]\|\\.\)*\)"\|\(\([^ \]\|\\.\)*\)\).*/\2\4/;s/\\\([^\\]\)/\1/g;s/\\$//g;s/\\\\/\\/g'

    netrc="$HOME/.netrc"
    if [ ! -f "$netrc" ]
    then
        log "parse_netrc(): netrc ($netrc) does not exist."

        log 'parse_netrc(): END'

        return 1
    fi

    if is_insecure $netrc
    then
        echo 'Warning: .netrc has insecure permissions.' >&2

        log 'parse_netrc(): netrc is insecure'

        log 'parse_netrc(): asking to fix netrc security'
        read -p 'Do you want to fix it? [Y/n] ' fix
        log "parse_netrc(): asked to fix netrc; fix = $fix"

        case $fix in
        [yY][eE][sS]|[yY])
            log 'parse_netrc(): securing netrc'
            make_secure $netrc
            ;;

        *)
            log 'parse_netrc(): not securing netrc'
            ;;
        esac
    fi

    cred="$(sed -n '/machine my\.rochester\.edu/,/machine /p' $netrc)"
    id="$(echo "$cred" | sed "$regexid")"
    password="$(echo "$cred" | sed "$regexpass")"

    log "parse_netrc(): \$cred = '$cred'; \$id = '$id'"

    log "parse_netrc(): END"
}

# has_valid_session()
# {
#     $logged_in || return 0
# 
#     # TODO - implement this
#     if true
#     then
#         logged_in=true
#         return 0
#     fi
# 
#     logged_in=false
#     password=
# 
#     return 1
# }

send_request()
{
    log 'send_request(): BEGIN'

    html="$(curl $curl_args "$@")"

    err=$?
    if [ $err != 0 ]
    then
        echo 'Error: request failed.' >&2

        log "send_request(): curl failed; error code $err"

        log 'send_request(): END'

        return 1
    fi

    TS="$(printf %s "$html" | grep -o -e 'TS=[0-9]\{13\}' | tail -1)"
    if [ -n "$TS" ]
    then
        log "send_request(): setting \$ts = '$TS'"

        ts="$TS"
    fi

    printf "%s\n" "$html"

    log 'send_request(): END'
}

log_in()
{
    log 'log_in(): BEGIN'

    parse_netrc

    while [ -z "$id" ]
    do
        log "log_in(): \$id = '$id'; reading id"
        read -p 'Net ID: ' id
        log "log_in(): read id; \$id = '$id'"
    done

    while [ -z "$password" ]
    do
        log 'log_in(): reading password'
        stty -echo
        read -r -p 'Password: ' password; echo
        stty echo
        log 'log_in(): read password'
    done

    [ -n "$q" ] || echo 'Logging in...'

    log 'log_in(): sending login request'

    # I don't think all these requests are necessary, but I'm not sure which
    # ones are, so I'm just leaving them all in. TODO - remove unnecessary
    # requests.
    {
        send_request 'https://webreg.its.rochester.edu/prod/tapp' --data "Navigate=redirect.jsp&OnError=LoginError.jsp&START_APP=true&JSP_TYPE=web&$ts&TRX_ID=ValidateStudent&CHECK_REG_RESTR=true&LDAP_AUTH=true&LOAD_DEF_LOG_TERM=true&LOAD_COUNTRY_CODES=true&LOAD_STATE_CODES=true&LOAD_COLLEGE_CODES=true&LOAD_HOLD_CODES=true&LOAD_RESTRICTION_CODES=true&LOAD_RELATIONSHIP_CODES=true&STUDENT_ID=$id&STUDENT_PIN=$password" >/dev/null
    } && {
        send_request 'https://webreg.its.rochester.edu/prod/tapp' --data "Navigate=redirect.jsp&OnError=LoginError.jsp&START_APP=true&JSP_TYPE=web&$ts&TRX_ID=ValidateStudent&CHECK_REG_RESTR=true&LDAP_AUTH=true&LOAD_DEF_LOG_TERM=true&LOAD_COUNTRY_CODES=true&LOAD_STATE_CODES=true&LOAD_COLLEGE_CODES=true&LOAD_HOLD_CODES=true&LOAD_RESTRICTION_CODES=true&LOAD_RELATIONSHIP_CODES=true&STUDENT_ID=$id&STUDENT_PIN=$password" >/dev/null
    } && {
        send_request 'https://webreg.its.rochester.edu/prod/tapp?Navigate=RchHoldsIndex.jsp&OnError=error.jsp' >/dev/null
    } && {
        send_request "https://webreg.its.rochester.edu/prod/tapp?Navigate=classindex.jsp&WAITPAGE=Loading.htm&LOAD_TERMS=true&TRX_ID=GetCollegeRegTerms&LOAD_DEF_REG_TERM=true&LOAD_SCHEDULE=true&OnError=error.jsp&$ts" >/dev/null
    } && {
        send_request "https://webreg.its.rochester.edu/prod/tapp?Navigate=classindex.jsp&WAITPAGE=Loading.htm&LOAD_TERMS=true&TRX_ID=GetCollegeRegTerms&LOAD_DEF_REG_TERM=true&LOAD_SCHEDULE=true&OnError=error.jsp&$ts" >/dev/null
    } && {
        send_request "https://webreg.its.rochester.edu/prod/web/scheduletopbar.jsp?$ts" >/dev/null
    } && {
        send_request "https://webreg.its.rochester.edu/prod/web/regmain.jsp?$ts" >/dev/null
    } && {
        send_request "https://webreg.its.rochester.edu/prod/web/classschedule.jsp?$ts" >/dev/null
    } || {
        echo 'Error: unable to log in.' >&2

        log 'log_in(): Error: unable to log in'

        log 'log_in(): END'

        return 1
    }

    log 'log_in(): should be successfully logged in'

    log 'log_in(): END'
}

is_valid_crn()
{
    printf %s "$1" | grep -q '[0-9]\{5\}' || {
        log "is_valid_crn(): $1 => FALSE"
        return 1
    }

    log "is_valid_crn(): $1 => TRUE"
}

read_crn()
{
    log 'read_crn(): BEGIN'

    while true
    do
        while true
        do
            log "read_crn(): \$crn = '$crn'; reading crn"
            read -p 'CRN: ' crn
            log "read_crn(): read crn; \$crn = '$crn'"

            if [ -z $crn ]
            then
                log 'read_crn(): $crn is empty; returning'

                log 'read_crn(): END'

                return 1
            fi

            if is_valid_crn $crn
            then
                log "read_crn(): using \$crn = '$crn'"
                break
            fi

            echo 'Error: invalid CRN.' >&2

            log 'read_crn(): invalid crn entered; looping'
        done

        if ! $CONFIRM_CRN
        then
            log 'read_crn(): skipping crn confirmation'

            return 0
        fi

        log "read_crn(): \$crn_confirm = '$crn_confirm'; reading crn"\
            "confirmation"

        read -p 'CRN confirmation: ' crn_confirm
        log "read_crn(): read crn confirmation; \$crn_confirm = '$crn_confirm'"

        if [ "$crn" = "$crn_confirm" ]
        then
            log "read_crn(): CRNs $crn and $crn_confirm match"

            log 'read_crn(): END'

            return 0
        fi

        echo 'Error: CRNs do not match.' >&2

        log "read_crn(): CRNs $crn and $crn_confirm do not match; looping"
    done

    log 'read_crn(): Error: reached unreachable statement.'
}

read_crns()
{
    log 'read_crns(): BEGIN'

    while read_crn
    do
        crns="$crns $crn"

        log "read_crns(): crn read; \$crn = '$crn'; \$crns = '$crns'"
    done

    if [ -z "$crns" ]
    then
        echo 'Warning: you have not entered any classes to register for.' >&2

        log 'read_crns(): \$crns is empty; not registering for any classes'

        log 'read_crns(): END'

        return 1
    fi

    log 'read_crns(): END'

    return 0
}

add_course()
{
    log 'add_course(): BEGIN'

    crn="$1"

    log "add_course(): using \$crn = '$crn'"

    # 'A' is for auditing; 'N' is for normal grading
    if [ "$2" = 'A' ]
    then
        gt=A

        log "add_course(): grade type given; \$gt = '$gt'"
    else
        gt=N

        log "add_course(): grade type not given; \$gt = '$gt'"
    fi

    echo "Adding course $crn"

    {
        send_request "https://webreg.its.rochester.edu/prod/tapp?Navigate=regdisplay1.jsp&OnError=error.jsp&$ts&ADD_CALL_NUM=15156&LOAD_SCHEDULE=false&SHOP_CART=true&GRADE_TYPE=N" >/dev/null
    } && {
        send_request "https://webreg.its.rochester.edu/prod/tapp?Navigate=CartResults.jsp&OnError=error.jsp&$ts&SUBMIT_CART=true&WAITPAGE=PleaseWait.htm" >/dev/null
    } && (
        html="$(send_request "https://webreg.its.rochester.edu/prod/tapp?Navigate=CartResults.jsp&OnError=error.jsp&$ts&SUBMIT_CART=true&WAITPAGE=PleaseWait.htm")"

        if printf "%s\n" "$html" | grep -qF "Permission required"; then
            log 'add_course(): Error: permission code required'
            echo 'Error: permission code required.' >&2
            exit 1
        elif printf "%s\n" "$html" | grep -qF "Unable"; then
            log 'add_course(): Error: unable to register'
            echo 'Error: unable to add course.' >&2
            echo 'Trying again in 5 seconds...' >&2
            sleep 5
            log 'add_course(): Trying again'
            add_course "$@" || exit 1
        elif printf "%s\n" "$html" | grep -qF "Cannot"; then
            log 'add_course(): Error: cannot register at this time'
            echo 'Error: cannot register at this time.' >&2
            echo 'Trying again in 5 seconds...' >&2
            sleep 5
            log 'add_course(): Trying again'
            add_course "$@" || exit 1
        fi
    ) || {
        echo 'Error: unable to add course.' >&2

        log 'add_course(): Error: unable to add course'

        log 'add_course(): END'

        return 1
    }

    [ -n "$q" ] || echo "Course $crn has been successfully added."

    log 'add_course(): course should be successfully added'

    log 'add_course(): END'
}

[ -n "$q" ] || {
    echo 'Enter the CRNs you wish to register for.'
    echo 'End your list by entering an empty CRN.'
}

if ! read_crns
then
    log 'no CRNs entered'

    log 'END'

    exit 0
fi

if ! log_in
then
    log 'log_in failed'

    log 'END'

    exit 1
fi

for crn in $crns
do
    if ! add_course $crn
    then
        log "adding course $crn failed"

        log 'END'

        exit 1
    fi
done

log 'END'