#!/system/bin/sh
# wget-curl, a curl wrapper acting as a wget drop-in replacement - version git-HEAD
# Usage: wget [wget args] [i need to fill this in later] <url(s)>
# Download all URLs given using curl, but using wget's options.
#
#
# End of help.
# Copyright (c) 2015 Kylie McClain <somasis@exherbo.org>
#
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
# REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
# AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
# OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
# PERFORMANCE OF THIS SOFTWARE.
#
# End of copyright.
#

set -o pipefail
shopt -u shift_verbose >/dev/null 2>&1

help() {
    sed -n '/^#/!d;s/^# //;s/^#//;3,${p;}' "$0" | \
        while IFS= read help_line;do
            if [[ "$help_line" == "End of help." ]];then
                exit 0
            else
                printf "%s\n" "$help_line"
            fi
        done
    exit 0
}

version() {
    sed 's/^# //;s/, .* - version / /;2q;$!d' "$0"
    copyright
    exit 0
}

copyright() {
    sed -n '/^#/!d;s/^# //;s/^#//;/End of help./,${p;}' "$0" | \
        while IFS= read copyright_line;do
            if [[ "$copyright_line" == "End of help." ]];then
                true
            elif [[ "$copyright_line" == "End of copyright." ]];then
                break
            else
                printf '%s\n' "$copyright_line"
            fi
        done
}

stderr() {
    printf "$@" >&2
}

error() {
    stderr "$0: $1\n"
    exit "$2"
}

invalid_arg() {
    error "invalid option -- '$1'" 2
}

append_opt() {
    for opt in $@;do
        CURL_OPTS="${CURL_OPTS} ${opt}"
    done
}

curl() {
    eval "command curl $@ ${CURL_RAW}"
}

append_raw_arg() {
    CURL_RAW="$CURL_RAW $@"
}

has_opt() { # exit 0 if CURL_OPTS has arg, non-zero if doesn't
    if [[ "$CURL_OPTS" == *" $1"* ]];then
        return 0
    else
        return 1
    fi
}

reexec_without() { # download afterwards without $1 in OPTS
    reexec_args_without="$reexec_args_without $@"
    reexec=1
}

reexec_only() {
    for arg in $@;do
        CURL_OPTS_REEXEC_ONLY="${CURL_OPTS_REEXEC_ONLY} $arg"
    done
}

print_url() {
    has_opt -s || printf "%s\n" "$1"
}

# 46ABDFHIKLNOPQRSTUVXabcdhiklm nH nc nd np nv opqrtvwx
while getopts ':46ABDFHIKLNO:PQRST:U:VXa:bcdhiklmopqrtvwx' argument "$@";do
    case "$argument" in
        # a lot of these are noop right now because they are wget mirror args
        # which curl doesn't really do, and i am not sure if i should implement them
        4)  append_opt -4       ;;
        6)  append_opt -6       ;;
        A)  true                ;; # probably can't implement this easily...
        B)  true                ;;
        D)  true                ;;
        E)  true                ;;
        F)  true                ;; # curl doesn't care what the input is
        H)  true                ;;
        I)  true                ;;
        K)  true                ;;
        L)  true                ;;
        N)  true                ;;
        O)  append_opt "-o $OPTARG"                 ;;
        P)  true                ;;
        Q)  true                ;;
        R)  true                ;;
        S)  append_opt -I;reexec_without -I -s  ;;
        T)  append_opt "-m $OPTARG"                 ;;
        U)  append_opt "--user-agent \"$OPTARG\""   ;;
        V)  version; curl --version; exit 0         ;;
        X)  true                                    ;;
        a)  append_raw_arg "2>&1 | tee -a $OPTARG"  ;;
        b)
            wget_log="wget-log"
            i=1
            while [[ -f "${wget_log}" ]];do
                # if that exists, increment until we find something that doesn't
                i=$(($i+1))
                wget_log="wget-log.${i}"
            done
            append_raw_arg ">\"$wget_log\" 2>&1 &"
            printf "Continuing in background, pid %s.\nOutput will be written to '$wget_log'.\n" "$$"
        ;;
        c)  append_opt "-C -"                       ;;
        d)  append_opt "-v"                         ;;
        e)  true                                    ;;
        h)  help                                    ;;
        i)
            [[ ! -f "$OPTARG" ]] && error "$OPTARG does not exist" 3
            for url in $(<"$OPTARG");do
                URLS=( ${URLS[@]} "$url" )
            done
        ;;
        q)  append_opt "-s"                         ;;
    esac
    shift $(($OPTIND-1))
done

# set wget default equivilants
append_opt -L # follow redirects
append_opt -# # progress bar

if [[ -z "${URLS[@]}" ]];then
    URLS=( ${@} )
fi

for url in ${URLS[@]};do
    url_file=${url##*/}
    if [[ "$url" == "$url_file" ]];then
        # has no remote file name and -o is not in CURL_OPTS... assume index.html
        has_opt -o || append_opt "-o index.html"
    fi

    eval "print_url '$url';curl ${CURL_OPTS} -- $url"
    if [[ "$reexec" ]];then
        for reexec_arg in ${reexec_args_without};do
            CURL_OPTS_REEXEC=$(echo "${CURL_OPTS_REEXEC:-$CURL_OPTS}" | sed "s# $reexec_arg##")
        done
        eval "print_url '$url';curl ${CURL_OPTS_REEXEC} ${CURL_OPTS_REEXEC_ONLY} -- $url"
    fi
done