adding revenue handlers and shell

internal/model/revenue.go

@@ -21,14 +21,23 @@ type Period struct {
 }
 
 // RevenueCategory is what the revenue is broken down by
-type RevenueCategory string
+// RevenueCategory is now just a string — categories are dynamic per company
+type RevenueCategory = string
 
+// Built-in reserved categories
 const (
-	CategoryProduct  RevenueCategory = "product"
-	CategoryLocation RevenueCategory = "location"
-	CategoryTotal    RevenueCategory = "total"
+	CategoryTotal RevenueCategory = "total" // always required, never custom
 )
 
+// CategoryDef defines a custom category for a specific company
+// e.g. Company: Apple, Name: "product", Labels: ["iPhone", "Mac", "Services"]
+type CategoryDef struct {
+	ID      int
+	Company *Company
+	Name    string   // e.g. "product", "location", "segment"
+	Labels  []string // populated from category_labels table
+}
+
 // Revenue is a single line in a financial report
 type Revenue struct {
 	ID       int
@@ -59,11 +68,57 @@ func (r *RevenueReport) Total(category RevenueCategory) float64 {
 	return sum
 }
 
-// Validate checks that product + location sums match the total entry
-func (r *RevenueReport) Validate() (bool, float64, float64) {
-	total := r.Total(CategoryTotal)
-	products := r.Total(CategoryProduct)
-	locations := r.Total(CategoryLocation)
-	// both breakdowns should equal the total
-	return products == total && locations == total, products, locations
+// SumByCategory returns a map of category → sum for all entries
+func (r *RevenueReport) SumByCategory() map[RevenueCategory]float64 {
+	sums := make(map[RevenueCategory]float64)
+	for _, e := range r.Entries {
+		sums[e.Category] += e.Value
+	}
+	return sums
+}
+
+// Validate checks every category independently sums to total
+func (r *RevenueReport) Validate() (bool, map[RevenueCategory]float64) {
+	total := r.Total(CategoryTotal)
+	sums := r.SumByCategory()
+	delete(sums, CategoryTotal) // don't compare total to itself
+
+	allMatch := true
+	for cat, sum := range sums {
+		if sum != total {
+			allMatch = false
+			_ = cat // caller can inspect the map to see which failed
+		}
+	}
+	return allMatch, sums
+}
+
+// RevSum aggregates revenue across multiple reports or periods
+// Use this when you want e.g. FY = Q1+Q2+Q3+Q4
+type RevSum struct {
+	Company    *Company
+	Categories map[RevenueCategory]float64 // category → total across all periods
+	Labels     map[string]float64          // label → total (e.g. "iPhone" across quarters)
+	Total      float64
+	Periods    []Period // which periods were summed
+}
+
+func NewRevSum(company *Company, reports []RevenueReport) *RevSum {
+	rs := &RevSum{
+		Company:    company,
+		Categories: make(map[RevenueCategory]float64),
+		Labels:     make(map[string]float64),
+	}
+	for _, report := range reports {
+		rs.Periods = append(rs.Periods, report.Period)
+		for _, e := range report.Entries {
+			if e.Category == CategoryTotal {
+				rs.Total += e.Value
+				continue
+			}
+			rs.Categories[e.Category] += e.Value
+			rs.Labels[e.Label] += e.Value
+		}
+	}
+	return rs
 }