refactor

1 files changed, 55 insertions, 0 deletions

diff --git a/cover.go b/cover.go
new file mode 100644
index 0000000..30be2d6
--- /dev/null
+++ b/cover.go
@@ -0,0 +1,55 @@
+package lulu
+
+import (
+	"encoding/json"
+	"fmt"
+	"strconv"
+)
+
+//go:generate go run github.com/yawnak/string-enumer -t Unit --text -o ./cover_gen.go .
+
+// Unit is a unit of length measurement.
+type Unit string
+
+const (
+	Points      Unit = "pt"
+	Millimeters Unit = "mm"
+	Inches      Unit = "inch"
+)
+
+// coverDimensionsReq is the json body of a /cover-dimensions/ request.
+type coverDimensionsReq struct {
+	PkgId  PkgId `json:"pod_package_id"`
+	NPages uint  `json:"interior_page_count"`
+	Unit   Unit  `json:"unit"`
+}
+
+type CoverDimensions struct {
+	Width, Height float64
+	Unit          Unit
+}
+
+func (cd *CoverDimensions) UnmarshalJSON(data []byte) error {
+	s := string(data)
+	var alias struct {
+		Width, Height string
+		Unit          Unit
+	}
+	if err := json.Unmarshal(data, &alias); err != nil {
+		return fmt.Errorf("malformed %T: %q: %w", cd, s, err)
+	}
+
+	w, err := strconv.ParseFloat(alias.Width, 64)
+	if err != nil {
+		return fmt.Errorf("malformed %T.Width: %q: %w", cd, s, err)
+	}
+	h, err := strconv.ParseFloat(alias.Height, 64)
+	if err != nil {
+		return fmt.Errorf("malformed %T.Height: %q: %w", cd, s, err)
+	}
+
+	cd.Width = w
+	cd.Height = h
+	cd.Unit = alias.Unit
+	return nil
+}