Add per-report distributor path overrides

internal/config/reports.go

@@ -17,6 +17,10 @@ func (cfg Config) ReportModuleOverrides() (map[report.ID][]module.ConfigItem, er
 	})
 }
 
+func (cfg Config) ReportDistributorPathOverrides() (map[report.ID][]string, error) {
+	return traverseReportDistributorPathOverrides(cfg)
+}
+
 func normalizeReportModules(cfg *Config) error {
 	if cfg.Reports == nil {
 		cfg.Reports = map[string]ReportConfig{}
@@ -35,6 +39,11 @@ func validateReportModules(cfg Config) error {
 	return err
 }
 
+func validateReportDistributorPathOverrides(cfg Config) error {
+	_, err := traverseReportDistributorPathOverrides(cfg)
+	return err
+}
+
 type reportModuleTraversalOptions struct {
 	normalizeOptions bool
 	updateConfig     bool
@@ -82,6 +91,76 @@ func traverseReportModules(cfg *Config, opts reportModuleTraversalOptions) (map[
 	return overrides, nil
 }
 
+func traverseReportDistributorPathOverrides(cfg Config) (map[report.ID][]string, error) {
+	overrides := map[report.ID][]string{}
+	if cfg.Reports == nil {
+		return overrides, nil
+	}
+	reportRegistry := report.DefaultRegistry()
+	seenReports := map[report.ID]string{}
+	for key, reportCfg := range cfg.Reports {
+		reportID, err := report.IDForConfigKey(key)
+		if err != nil {
+			return nil, fmt.Errorf("reports.%s: %w", key, err)
+		}
+		if previous, ok := seenReports[reportID]; ok {
+			return nil, fmt.Errorf("reports.%s duplicates report override %q", key, previous)
+		}
+		seenReports[reportID] = key
+		if _, err := reportRegistry.Lookup(reportID); err != nil {
+			return nil, fmt.Errorf("reports.%s: %w", key, err)
+		}
+		if !reportCfg.Distributor.pathTemplatesSet {
+			continue
+		}
+		if err := validateReportDistributorPathTemplates(key, reportCfg.Distributor.PathTemplates); err != nil {
+			return nil, err
+		}
+		overrides[reportID] = append([]string(nil), reportCfg.Distributor.PathTemplates...)
+	}
+	return overrides, nil
+}
+
+func validateReportDistributorPathTemplates(reportKey string, templates []string) error {
+	name := fmt.Sprintf("reports.%s.distributor.path_templates", reportKey)
+	if len(templates) == 0 {
+		return fmt.Errorf("%s must contain at least one entry", name)
+	}
+	values := sampleDistributorTemplateValues()
+	seen := map[string]struct{}{}
+	for i, template := range templates {
+		itemName := fmt.Sprintf("%s[%d]", name, i)
+		rendered, err := renderDistributorTemplate(itemName, template, values, distributorTemplateVariables)
+		if err != nil {
+			return err
+		}
+		if err := ValidateDistributorReportPath(itemName, rendered); err != nil {
+			return err
+		}
+		if _, ok := seen[rendered]; ok {
+			return fmt.Errorf("%s renders duplicate path %q", name, rendered)
+		}
+		seen[rendered] = struct{}{}
+	}
+	return nil
+}
+
+func sampleDistributorTemplateValues() DistributorTemplateValues {
+	return DistributorTemplateValues{
+		LocationID:      "location",
+		ReportID:        "report",
+		RunID:           "run",
+		ArtifactGroup:   "artifact",
+		BatchOutputName: "report.md",
+		ValidStartDate:  "2026-05-29",
+		ValidEndDate:    "2026-05-30",
+		ValidStartTime:  "0000",
+		ValidEndTime:    "0000",
+		ValidStartStamp: "2026-05-29T0000",
+		ValidEndStamp:   "2026-05-30T0000",
+	}
+}
+
 func moduleItemsFromConfig(registry briefing.ModuleRegistry, reportKey string, items []ModuleConfigItem, normalizeOptions bool) ([]module.ConfigItem, []ModuleConfigItem, error) {
 	out := make([]module.ConfigItem, 0, len(items))
 	normalizedItems := append([]ModuleConfigItem(nil), items...)