ment

#!/bin/bash

( ####------------------------BEGIN-SUBSHELL-####
#--------------SETTINGS/VARS--------------------------------#
# https://www.xfree86.org/current/xmessage.1.html
ULIST=( 
    'www.gsp.com/cgi-bin/man.cgi?topic=%s&section=%s' 
    'man.cx/%s(%s)' 
    'www.freebsd.org/cgi/man.cgi?query=%s&sektion=%s&format=ascii'
    'sarata.com/manpages/%s.%s.html' 
)
MODE='view'
RDIR="$HOME/.config/mentat"
URLG="${ULIST[ 0 ]}"
PAGES=( {1..9} )
OUTDIR="${RDIR}/mentatpages"
RECSDIR="${RDIR}/Recs/"
NOCACHE='0'
VIEW_PG='1'
#--------------INITILIZE_DIRECTORIES------------------------#
if ! [[ -d "${RDIR}"    ]] ; then mkdir "${RDIR}"    ; fi
if ! [[ -d "${OUTDIR}"  ]] ; then mkdir "${OUTDIR}"  ; fi
if ! [[ -d "${RECSDIR}" ]] ; then mkdir "${RECSDIR}" ; fi
#--------------VIEW_AND_DUMP_FUNCTIONS----------------------#
if   command -v "lynx"  &>/dev/null
then function mlink_view()   { lynx  -cmd_script="${RECSDIR}/cmd_script_lynx.txt" "${1}" ; }
     function mlink_dump()   { lynx  -dump -nonumbers "${1}" ; }
elif command -v "links" &>/dev/null
then function mlink_dump()   { links -dump -html-numbered-links 0 -no-g  "${1}" ; }
     function mlink_view()   { links "${1}" ; }
elif command -v "curl"  &>/dev/null
then function mlink_view()   { curl  --use-ascii "${1}" ; }
     function mlink_dump()   { curl  "${1}" ; }
else echo "No web program found."
     return '1'
fi
function mlink_nvim() {
    nvim -c "$(printf 'vnew Web | call termopen(" %s ") | only'\
                      "lynx -cmd_script='${RECSDIR}/cmd_script_lynx.txt' '${1}'")"
}
#--------------HELPER_GET-----------------------------#
function get_subname() {
    grep -Pio '^([a-zA-Z]*://)?([ \t]*www.)?\K[^./]*' <<< "${1}"
}
function get_url() {
    tmpfile="$(mktemp)" ; echo "${tmpfile}"
    mlink_dump "${1}" > "${tmpfile}" 
    if   str_beg="$(grep -Pn --max-count=1 '^NAME[ \t]*$' "${tmpfile}" | grep -Po '^[0-9]+(?=[^0-9])')"
    then str_end="$(grep -Pn '^[A-Z]+[ \t]*$' "${tmpfile}" | tail -1 | grep -Po '^[0-9]+(?=[^0-9])')"
         sed -i -n "$((str_beg-1)),$((str_end+5))p" "${tmpfile}"
    else
        return "1"
    fi
}
#--------------GET----------------------#
function get_man() {
    cmg_fn="${OUTDIR}/$(get_subname "${URLG}").${CNAME}"

    for i in "${PAGES[@]}" ; do
        if ! [[ "${NOCACHE}" -eq "1" ]] && ls -1 "${cmg_fn}.${i}" &>/dev/null
        then echo "${cmg_fn}.${i}"$'\n\t''has already been downloaded, use --nocache to ignore and redownload.'
        else
            mdurl="$(printf "https://${URLG}" "${CNAME}" "${i}")"
            if ztop="$(get_url "${mdurl}")" ; then 
                if command -v "txt2man" &>/dev/null
                then txt2man "${ztop}" > "${cmg_fn}.${i}"
                else     cat "${ztop}" > "${cmg_fn}.${i}"
            fi ; fi

            if [[ -f "${ztop}" ]] ; then rm "${ztop}"; fi
        fi
    done
}
function get_all() {
    while [[ "${i:=0}" -lt ${#URL[@]} ]] ; do
        get_man "${ULIST[ i++ ]}"
    done
}
#--------------HANDLE_ARGS--------------#
function handle_args() {
    case "${1,,}" in 
            --url) URLG="${2}"    ; shift 1
    ;; --view-num) VIEW_PG="${2}" ; shift 1
    ;;  --nocache) NOCACHE='1'   
    ;;      --all) MODE='all' 
    ;;     --view) MODE='view'
    ;;     --dump) MODE='dump'
    ;;      --get) MODE='get' 
    ;;     --nvim) MODE='nvim'
    ;; -*) echo "OPTION ${1} NOT FOUND"     ; return "1"
    ;; "") echo "COMMAND NAME NOT PROVIDED" ; return "1"
    ;;  *) CNAME="${*}"                     ; return "$?"
    esac ; shift 1; handle_args "${@}"
}
#--------------MAIN---------------------#
function main() {
    if ! handle_args "${@}" ; then return "1" ; fi

    case "${MODE,,}" in 
        get)    get_man "${URLG}"
    ;;  all)    get_all
    ;; view)    mlink_view "$(printf "${URLG}" "${CNAME}" "${VIEW_PG}")"
    ;; dump)    mlink_dump "$(printf "${URLG}" "${CNAME}" "${VIEW_PG}")"
    ;; nvim)    mlink_nvim "$(printf "${URLG}" "${CNAME}" "${VIEW_PG}")"
    ;;          *)  echo "Error, mode is undefined"; return 1
    esac
}

main "${@}"
) ####------------------------END-SUBSHELL-####