package document

import (
	"Scanyonero/unit"
	"regexp"
)

type IngestorRule struct {
	// All entries that are non nil have to match.
	Match struct {
		Name    *regexp.Regexp // When this regular expression matches with the filename/filepath then the rule is used.
		XPixels *int           // When the scanned image width in pixels matches with the given amount of pixels, the rule is used.
		YPixels *int           // When the scanned image height in pixels matches with the given amount of pixels, the rule is used.
	}

	// All non nil entries will be applied to the document pages.
	Action struct {
		MediumWidth  *unit.Millimeter // Sets the width of the medium.
		MediumHeight *unit.Millimeter // Sets the height of the medium.
		ScanOffsetX  *unit.Millimeter // Offsets the scan in the medium on the x axis.
		ScanOffsetY  *unit.Millimeter // Offsets the scan in the medium on the y axis.
	}
}

// Apply will check and apply the rule per ingested page.
func (rule IngestorRule) Apply(ingestor Ingestor, file File, page *Page) error {
	// Match.

	if rule.Match.Name != nil && !rule.Match.Name.MatchString(file.Name) {
		return nil
	}
	imageBounds := page.Image.Bounds()
	if rule.Match.XPixels != nil && *rule.Match.XPixels != imageBounds.Dx() {
		return nil
	}
	if rule.Match.YPixels != nil && *rule.Match.YPixels != imageBounds.Dy() {
		return nil
	}

	// Apply actions.

	if rule.Action.MediumWidth != nil {
		page.Dimensions.MediumSize.X = *rule.Action.MediumWidth
	}
	if rule.Action.MediumHeight != nil {
		page.Dimensions.MediumSize.Y = *rule.Action.MediumHeight
	}
	if rule.Action.ScanOffsetX != nil {
		page.Dimensions.ScanSize.Origin.X = *rule.Action.ScanOffsetX
	}
	if rule.Action.ScanOffsetY != nil {
		page.Dimensions.ScanSize.Origin.Y = *rule.Action.ScanOffsetY
	}

	return nil
}