print multi-line text with spaces aligned on the first line

Issue:

I write relatively complex functions where I have to make up the code with spaces.

It is expected that the first line with the content (non-space character) will be determined, N spaces will be cut from it UP to the first non-space character.

Then, in all subsequent lines, the previously determined N-th number of spaces will also be cut out.

Expectation examples:

Let's say there is a certain print function.

In all subsequent cases, my expectation is:

this is the first line,
    this is the second line
  this is the third line.

Example of the cases used:

print '
    this is line one
        this is line two
      this is line three
    '

print '
            this is line one
                this is line two
              this is line three
            '

tmp() {
    tmp2() {
        print '
            this is line one
                this is line two
              this is line three
            '
    }
    tmp2
}
tmp

UPD: based on the practice of analyzing the answers to the issue, I added another one test:

tmp() {
    tmp2() {
        print '
            this
                this is line two
              this is line three
            '
    }
    tmp2
}
tmp

P.S.: My developments (works incorrectly)

print() {
    INPUT_STRING=$1
    
    # https://stackoverflow.com/questions/41010371/bash-counting-letters-in-string-output-always-a-little-different
    COUNT_SPACES_BEFORE_TEXT=$(printf '%s' "${INPUT_STRING}" | grep -o '[^\n]*' | wc -l)
    
    # https://stackoverflow.com/questions/5349718/how-can-i-repeat-a-character-in-bash
    STRING_SPACES=$(printf "%${COUNT_SPACES_BEFORE_TEXT}s" |tr " " " ")
    
    # https://stackoverflow.com/questions/23929235/multi-line-string-with-extra-space-preserved-indentation
    EXPR_SED='1d;$d;'
    EXPR_SED+="s/^${STRING_SPACES}//g"
    printf '%s' "${INPUT_STRING}" | sed "${EXPR_SED}"
}

Please tell me how to do it?

P.S.S.: please note that the input and output are strictly showed in the question.

1. It is not necessary to offer "similar" solutions like:

   printf '%s\n' \
       "this is line one" \
       "this is line two" \
       "this is line three"
   

2. No need to offer an analysis of my programming style, etc.

The entrance and exit are clearly indicated. I am going to ignore the answers/comments not on the subject

This is an implementation with awk, assuming tabs are not whitespace.

print(){
  printf "%s" "$@" |
  awk 'BEGIN{ len = -1 }
  NF>0 { if(len==-1){
              len = index($0,$1)-1; 
              prefix = substr($0,1,len) 
         }
       }
  /./ { start = substr($0,1,len)
        if(start==prefix){
           if(length($0)>len)print substr($0,len+1)
        } else print
  }'
}

The string is piped into awk and each line tested. len is set to -1.NF>0 is true if the line is not all spaces. $1 holds the first word. The index of that word in the line $0, minus 1, is the length of the prefix string of whitespace.

/./ matches non-empty lines. The first len characters are put in start. If this is the same as the prefix, the line is printed, starting from position len+1, unless the line is exactly just the whitespace prefix (such as at the end of the input; it is your choice). Else the line, which doesn't have the right whitespace is printed, (your choice).