Centralize generated text template catalog

internal/generatedtext/catalog.go

@@ -0,0 +1,155 @@
+package generatedtext
+
+import (
+	"fmt"
+
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/briefing"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/facts"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/report"
+	"gitea.maximumdirect.net/eric/weatherreporter/internal/reporttemplate"
+)
+
+const (
+	schemaIDHourly   = "hourly"
+	schemaIDTomorrow = "tomorrow"
+
+	templateIDHourly   = "hourly"
+	templateIDTomorrow = "tomorrow"
+)
+
+type validator func([]byte) (any, []byte, error)
+
+type renderContextBuilder func(report.ID, string, briefing.Metadata, module.Snapshot, facts.CollectedFacts, facts.DerivedFacts, any) (any, error)
+
+type catalogEntry struct {
+	schemaID           string
+	templateID         string
+	validate           validator
+	buildRenderContext renderContextBuilder
+}
+
+type Handler struct {
+	reportID           report.ID
+	schemaID           string
+	templateID         string
+	validate           validator
+	buildRenderContext renderContextBuilder
+}
+
+var catalog = []catalogEntry{
+	{
+		schemaID:           schemaIDHourly,
+		templateID:         templateIDHourly,
+		validate:           validateHourly,
+		buildRenderContext: buildHourlyContext,
+	},
+	{
+		schemaID:           schemaIDTomorrow,
+		templateID:         templateIDTomorrow,
+		validate:           validateTomorrow,
+		buildRenderContext: buildTomorrowContext,
+	},
+}
+
+func LookupDefinition(definition report.Definition) (Handler, error) {
+	if definition.GenerationMode != report.GenerationModeGeneratedTextTemplate {
+		return Handler{}, fmt.Errorf("report %q uses generation mode %q, not %q", definition.ID, definition.GenerationMode, report.GenerationModeGeneratedTextTemplate)
+	}
+
+	var schemaKnown, templateKnown bool
+	for _, entry := range catalog {
+		if entry.schemaID == definition.GeneratedTextSchemaID {
+			schemaKnown = true
+		}
+		if entry.templateID == definition.TemplateID {
+			templateKnown = true
+		}
+		if entry.schemaID == definition.GeneratedTextSchemaID && entry.templateID == definition.TemplateID {
+			return Handler{
+				reportID:           definition.ID,
+				schemaID:           entry.schemaID,
+				templateID:         entry.templateID,
+				validate:           entry.validate,
+				buildRenderContext: entry.buildRenderContext,
+			}, nil
+		}
+	}
+	if !schemaKnown {
+		return Handler{}, fmt.Errorf("generated text schema %q is not supported for report %q", definition.GeneratedTextSchemaID, definition.ID)
+	}
+	if !templateKnown {
+		return Handler{}, fmt.Errorf("report template %q is not supported for report %q", definition.TemplateID, definition.ID)
+	}
+	return Handler{}, fmt.Errorf("generated text schema %q and report template %q are not supported together for report %q", definition.GeneratedTextSchemaID, definition.TemplateID, definition.ID)
+}
+
+func (h Handler) SchemaID() string {
+	return h.schemaID
+}
+
+func (h Handler) TemplateID() string {
+	return h.templateID
+}
+
+func (h Handler) Schema() ([]byte, error) {
+	data, err := reporttemplate.Schema(h.schemaID)
+	if err != nil {
+		return nil, fmt.Errorf("load generated text schema %q for report %q: %w", h.schemaID, h.reportID, err)
+	}
+	return data, nil
+}
+
+func (h Handler) Template() (string, error) {
+	source, err := reporttemplate.Template(h.templateID)
+	if err != nil {
+		return "", fmt.Errorf("load report template %q for report %q: %w", h.templateID, h.reportID, err)
+	}
+	return source, nil
+}
+
+func (h Handler) Validate(data []byte) (any, []byte, error) {
+	if h.validate == nil {
+		return nil, nil, fmt.Errorf("generated text validator is not registered for schema %q on report %q", h.schemaID, h.reportID)
+	}
+	return h.validate(data)
+}
+
+func (h Handler) BuildRenderContext(metadata briefing.Metadata, snapshot module.Snapshot, collected facts.CollectedFacts, derived facts.DerivedFacts, generated any) (any, error) {
+	if h.buildRenderContext == nil {
+		return nil, fmt.Errorf("render-context builder is not registered for template %q on report %q", h.templateID, h.reportID)
+	}
+	return h.buildRenderContext(h.reportID, h.templateID, metadata, snapshot, collected, derived, generated)
+}
+
+func (h Handler) Render(data any) ([]byte, error) {
+	rendered, err := reporttemplate.Render(h.templateID, data)
+	if err != nil {
+		return nil, fmt.Errorf("render report template %q for report %q: %w", h.templateID, h.reportID, err)
+	}
+	return rendered, nil
+}
+
+func validateHourly(data []byte) (any, []byte, error) {
+	return ValidateHourly(data)
+}
+
+func validateTomorrow(data []byte) (any, []byte, error) {
+	return ValidateTomorrow(data)
+}
+
+func buildHourlyContext(reportID report.ID, templateID string, metadata briefing.Metadata, snapshot module.Snapshot, collected facts.CollectedFacts, derived facts.DerivedFacts, generated any) (any, error) {
+	hourly, ok := generated.(Hourly)
+	if !ok {
+		return nil, fmt.Errorf("report template %q requires hourly generated text for report %q", templateID, reportID)
+	}
+	return BuildHourlyRenderContext(metadata, snapshot, hourly, collected, derived)
+}
+
+func buildTomorrowContext(reportID report.ID, templateID string, metadata briefing.Metadata, snapshot module.Snapshot, collected facts.CollectedFacts, derived facts.DerivedFacts, generated any) (any, error) {
+	tomorrow, ok := generated.(Tomorrow)
+	if !ok {
+		return nil, fmt.Errorf("report template %q requires tomorrow generated text for report %q", templateID, reportID)
+	}
+	return BuildTomorrowRenderContext(metadata, snapshot, tomorrow, collected, derived)
+}