This script creates a "heatmap" table on Indesign. Uses tint values based on the cell's percentage value (from 100% to 0%)

IndesignColorHeatmapTable.jsx

/*
This script creates a "heatmap" table on Indesign:

- Checks for existing swatches named "HeatMapTableColor1", "HeatMapTableColor2", etc.
- Shows an error if no swatches are found with this naming pattern
- Shows an error if there aren't enough swatches for the table's columns
- Applies the colors in order (Color1 to first column, Color2 to second column, etc.)
- Uses tint values based on the cell's percentage value (from 100% to 0%)
- Maintains the text color logic (white text on dark backgrounds)
- If you don't want for the script to add a % after the values, if not present, comment the "// Add percentage sign if not present" block.

HOW TO USE:

First create your swatches in InDesign:
Name them "HeatMapTableColor1", "HeatMapTableColor2", etc.
Create at least as many swatches as you have table columns
Then:
1. Select your table (including its header)
2. Run the script
3. The colors will be applied automatically

The script will give helpful error messages if:
    No HeatMapTableColor swatches are found
    Not enough swatches are found for the number of columns

*/

// @target indesign
main();

function main() {
    if (app.documents.length == 0) {
        alert("Please open a document with a table.");
        return;
    }
    
    var doc = app.activeDocument;
    var selection = app.selection[0];
    
    if (!(selection instanceof Table)) {
        alert("Please select a table.");
        return;
    }
    
    // Get all available HeatMapTableColor swatches
    var heatMapColors = [];
    for (var i = 1; i <= 10; i++) { // Check up to 10 colors
        var swatchName = "HeatMapTableColor" + i;
        try {
            var swatch = doc.swatches.itemByName(swatchName);
            swatch.name; // Will throw error if swatch doesn't exist
            heatMapColors.push(swatchName);
        } catch (e) {
            // Swatch doesn't exist, skip it
            continue;
        }
    }
    
    // Check if we have any heat map colors defined
    if (heatMapColors.length === 0) {
        alert("No HeatMapTableColor swatches found!\n\nPlease create swatches named 'HeatMapTableColor1', 'HeatMapTableColor2', etc. before running this script.");
        return;
    }
    
    var table = selection;
    var numColumns = table.columns.length;
    
    // Check if we have enough colors for the table
    if (heatMapColors.length < numColumns) {
        alert("Not enough color swatches!\n\nTable has " + numColumns + " columns but only found " + heatMapColors.length + " HeatMapTableColor swatches.\n\nPlease create more swatches following the naming pattern 'HeatMapTableColorN'.");
        return;
    }
    
    // Process each cell in the table
    for (var rowIndex = 0; rowIndex < table.rows.length; rowIndex++) {
        var row = table.rows[rowIndex];
        for (var colIndex = 0; colIndex < numColumns; colIndex++) {
            var cell = row.cells[colIndex];
            var cellContent = cell.contents.toString();
            cellContent = cellContent.replace(/%/g, '');
            var value = parseFloat(cellContent);
            
            if (!isNaN(value)) {
                // Get color for this column
                var swatchName = heatMapColors[colIndex];
                
                // Calculate tint - linear scale from 0 to 100
                var tint = value;
                
                // Apply formatting
                cell.fillColor = doc.swatches.itemByName(swatchName);
                cell.fillTint = tint;
                
                // Set text color based on tint
                if (tint > 50) {
                    cell.texts[0].fillColor = doc.swatches.itemByName("Paper");
                } else {
                    cell.texts[0].fillColor = doc.swatches.itemByName("Black");
                }
                
                // Add percentage sign if not present
                if (cell.contents.toString().indexOf('%') === -1) {
                    cell.contents = value.toString() + '%';
                }
            }
        }
    }
}

Example table after running the script: