CSV To Markdown Table

script

function parse_CSV(csv_string){
  rows=[]
  row=[]

  in_string=false
  cell_value=""
    
  for(ch of csv_string){
    if(ch==','){
      // Might be a cell separator
      if(in_string==false){
        // Is cell separator
        row.push(cell_value)
        cell_value=""
      }else{
        // In a cell and not a separator
        cell_value+=ch
      }
    }else if(ch=='\n' && in_string==false){
      // New row
      if(cell_value!=''){
        // Existing cell to add to row
        row.push(cell_value)
        cell_value=""
      }
      rows.push(row)
      row=[]
    }else if(ch=='"'){
      // String start or end
      if(in_string==false) {
        // String start
        in_string=true
      }else{
        // String end
        in_string=false
        row.push(cell_value)
        cell_value=""
      }
    }else{
      // normal character
      cell_value+=ch
    }
  }
  
  if(cell_value!=""){
    row.push(cell_value)
  }
  
  if(row.length>0){
    rows.push(row)
  }

  return rows
}

// Work out what the column types are
//
// L = Left alignment
// R = Right alignment
//
function get_column_types(cellArray){
  col_has_numeric=[]
  col_has_nonnumeric=[]
  col_count=0

  // Figure out how many columns we have
  for(row of cellArray){
    col_count=Math.max(col_count,row.length)
  }
  
  // Prime column detected types array
  for(i=0;i<col_count;i++){
    col_has_numeric.push(0)
    col_has_nonnumeric.push(0)
  }

  // Loop through rows to figure out type of each cell
  for(row of cellArray){
    row_length=row.length
    for(i=0;i<row_length;i++){
      if(isNaN(row[i])){
        col_has_nonnumeric[i]++
      }else{
        col_has_numeric[i]++
      }
    }
  }
  
  alignments=[]
  for(i=0;i<col_count;i++){
    if(col_has_nonnumeric[i]>0){
      alignments.push("L")
    }else{
      alignments.push("R")
    }
  }
  return alignments
  
}

// Format a one-dimensional array of text cells as a line with newline
function format_row(cells){
  rowText="|"
  for(cell of cells){
    rowText+=cell+"|"
  }
  return rowText+"\n"
}

// Extract the selected text and parse into an array of rows
csv=editor.getSelectedText()
rows=parse_CSV(csv)
rowCount=rows.length

// Prepare a dialog to control Markdown table generation
p=Prompt.create()
p.title="Control Markdown Table Creation"
p.addSwitch("heading","First row is heading",true)
p.addButton("OK")

// Display this dialog
p.show()

// If not cancelled then handle result of the dialog
if(p.buttonPressed=="OK"){

  // Glean column alignments as an array
  alignments=get_column_types(rows)

  // Format alignment row
  alignmentRow="|"
    
  for(a of alignments){
    if(a=="L"){
      alignmentRow+=":-|"
    }else{
      alignmentRow+="-:|"
    }
   }

  if(p.fieldValues["heading"]==false){
    // Text starts with empty header
    replacementText="||\n"+alignmentRow+"\n"
    
    // Add the rows
    for(row of rows){
      replacementText+=format_row(row)
    }
  }else{
    // Calculate number of cells in longest row
    columns=0
    for(row of rows){
      columns=Math.max(columns,row.length)
    }

   // Replacement text starts with the first row
    replacementText=format_row(rows[0])
    
    // Now add alignment row
    replacementText+=alignmentRow+"\n"
   
    // Now add the rest of the rows
    for(row=1;row<rowCount;row++){
      replacementText+=format_row(rows[row])
    }
  }
  
  // Replace the selected text with the Markdown table version
  if(replacementText!=""){
    editor.setSelectedText(replacementText)
  }
}