.sub hex2decimal 
    .param string hex
    .local int result
    .local int position
    .local string digits
    .local int len
    result = 0
    position = 0
    digits = '0123456789ABCDEF'
    upcase hex
    len = length hex
p_hex_loop:
    if position == len goto p_hex_over
    result *= 16
    $S1 = hex[position]
    $I1 = index digits, $S1
    result += $I1
    inc position
    goto p_hex_loop
    
p_hex_over:
    .return(result)
.end


.sub url_decode 
    .param string theURL
    .local int position
    # + becomes space
p_unesc_url_space:
    position = index theURL, '+'
    if position == -1 goto p_unesc_url_others_0
    theURL[position] = ' '
    goto p_unesc_url_space
p_unesc_url_others_0:
    position = 0
p_unesc_url_others:
    position = index theURL, '%', position
    if position == -1 goto p_unesc_url_over
    $I1 = position + 1
    $S1 = substr theURL, $I1, 2
    $I1 = hex2decimal($S1)
    $S1 = chr $I1
    theURL = substr position, 3, $S1 
    inc position
    goto p_unesc_url_others
p_unesc_url_over:
    .return(theURL)
.end



.sub get_query_params 
    .param string query
    .local pmc result
    result = new .Hash
    
    
    .local int start
    .local int end
    .local int len
    .local string key
    .local string value
    start = 0
parse:    
    index end, query, '=', start
    if end == -1 goto ret
    len = end - start 
    substr key, query, start, len
    key = url_decode(key)
    start = end + 1
    index end, query, '&', start
    if end > -1 goto more_data
        substr value, query, start
        value = url_decode(value)
        result[key] = value
        goto ret
    more_data:
        len = end - start
        substr value, query, start, len
        value = url_decode(value)
        result[key] = value
        start = end + 1
        goto parse
ret:
    
    .return(result)
    
.end
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