// Hook: AfterPowerPoint
// Replace simple tokens in slide text without losing the existing formatting.
//
// Walks every slide / shape / paragraph / portion and substitutes the tokens
// {{JobName}}, {{OutputName}}, {{Today}}, and {{Region}} (the last from the
// job parameters). Replacing at portion level preserves font and colour -
// a naive TextFrame.Text = ... assignment would destroy that formatting.

if (Presentation == null || Presentation.Slides.Count == 0)
{
    AddWarning($"Presentation for '{OutputName}' is empty; nothing to substitute.");
    return;
}

var tokens = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
{
    ["{{JobName}}"]    = JobName ?? string.Empty,
    ["{{OutputName}}"] = OutputName ?? string.Empty,
    ["{{Today}}"]      = $"{DateTime.Now:MMMM d, yyyy}",
    ["{{Region}}"]     = Parameters.TryGetValue("Region", out var r) ? r : string.Empty,
};

int replacements = 0;

foreach (var slide in Presentation.Slides)
{
    foreach (var shape in slide.Shapes)
    {
        var autoShape = shape as IAutoShape;
        if (autoShape?.TextFrame == null) continue;

        foreach (var paragraph in autoShape.TextFrame.Paragraphs)
        {
            foreach (var portion in paragraph.Portions)
            {
                var original = portion.Text ?? string.Empty;
                var updated = original;

                foreach (var kv in tokens)
                {
                    if (updated.IndexOf(kv.Key, StringComparison.OrdinalIgnoreCase) >= 0)
                        updated = updated.Replace(kv.Key, kv.Value);
                }

                if (original != updated)
                {
                    portion.Text = updated;
                    replacements++;
                }
            }
        }
    }
}

Logger.LogInformation($"Token substitution made {replacements} replacement(s) in '{OutputName}'.");