got a exporter for forecasting

internal/model/model.go

@@ -1,6 +1,9 @@
 package model
 
-import "time"
+import (
+	"fmt"
+	"time"
+)
 
 type GLAccountType string
 
@@ -361,3 +364,77 @@ type PnLRequest struct {
 	DeptCodes     []string
 	Version       BudgetVersion
 }
+
+// ForecastIngestRequest is the payload an external model POSTs back
+// after consuming the export endpoint.
+type ForecastIngestRequest struct {
+	Department string         `json:"department"`
+	FiscalYear int            `json:"fiscal_year"`
+	Version    BudgetVersion  `json:"version"`
+	CreatedBy  string         `json:"created_by"`
+	Lines      []ForecastLine `json:"lines"`
+}
+
+type ForecastLine struct {
+	FiscalPeriod int     `json:"period"`
+	GLCode       string  `json:"gl_code"`
+	Amount       float64 `json:"amount"`
+	Currency     string  `json:"currency"`
+}
+
+func (f *ForecastIngestRequest) Valid() []string {
+	var errs []string
+
+	if f.Department == "" {
+		errs = append(errs, "department is required")
+	}
+	if f.FiscalYear < 1 || f.FiscalYear > 2200 {
+		errs = append(errs, "fiscal_year must be between 1 and 2200")
+	}
+	if f.Version == "" {
+		errs = append(errs, "version is required")
+	}
+	if f.Version == VersionOriginal {
+		errs = append(errs, "version cannot be original — forecasts must use forecast_1, forecast_2, or forecast_3")
+	}
+	if f.CreatedBy == "" {
+		errs = append(errs, "created_by is required")
+	}
+	if len(f.Lines) == 0 {
+		errs = append(errs, "lines must contain at least one record")
+	}
+
+	for i, line := range f.Lines {
+		if line.FiscalPeriod < 1 || line.FiscalPeriod > 12 {
+			errs = append(errs, fmt.Sprintf("lines[%d]: period must be between 1 and 12", i))
+		}
+		if line.GLCode == "" {
+			errs = append(errs, fmt.Sprintf("lines[%d]: gl_code is required", i))
+		}
+		if line.Amount <= 0 {
+			errs = append(errs, fmt.Sprintf("lines[%d]: amount must be greater than 0", i))
+		}
+		if line.Currency == "" {
+			errs = append(errs, fmt.Sprintf("lines[%d]: currency is required", i))
+		}
+	}
+
+	return errs
+}
+
+type ForecastPeriodRow struct {
+	FiscalPeriod int           `json:"period"`
+	GLCode       string        `json:"gl_code"`
+	GLType       GLAccountType `json:"gl_type,omitempty"`
+	Amount       float64       `json:"amount"`
+	Currency     string        `json:"currency,omitempty"`
+}
+
+type ForecastExport struct {
+	Department       string              `json:"department"`
+	FiscalYear       int                 `json:"fiscal_year"`
+	Version          BudgetVersion       `json:"version"`
+	PeriodsActual    []ForecastPeriodRow `json:"periods_actual"`
+	PeriodsBudget    []ForecastPeriodRow `json:"periods_budget"`
+	RemainingPeriods []int               `json:"remaining_periods"`
+}