Expose template options

internal/topdata/wiki_data_providers.go

@@ -18,6 +18,7 @@ type wikiDataProviderDefinition struct {
 	Levels         string                          `json:"levels" yaml:"levels"`
 	ClassFeats     wikiDataProviderClassFeatConfig `json:"class_feats" yaml:"class_feats"`
 	Attacks        wikiDataProviderAttacksConfig   `json:"attacks" yaml:"attacks"`
+	Facts          wikiDataProviderFactsConfig     `json:"facts" yaml:"facts"`
 	Provider       string                          `json:"provider" yaml:"provider"`
 	Columns        int                             `json:"columns" yaml:"columns"`
 	ItemsPerColumn int                             `json:"items_per_column" yaml:"items_per_column"`
@@ -32,6 +33,17 @@ type wikiDataProviderProjectionField struct {
 	When string `json:"when" yaml:"when"`
 }
 
+type wikiDataProviderFactsConfig struct {
+	Rows []wikiDataProviderFactRow `json:"rows" yaml:"rows"`
+}
+
+type wikiDataProviderFactRow struct {
+	Key   string `json:"key" yaml:"key"`
+	Label string `json:"label" yaml:"label"`
+	Value string `json:"value" yaml:"value"`
+	When  string `json:"when" yaml:"when"`
+}
+
 type wikiDataProviderAttacksConfig struct {
 	Field      string                               `json:"field" yaml:"field"`
 	CountField string                               `json:"count_field" yaml:"count_field"`
@@ -106,6 +118,18 @@ func loadWikiDataProviders(path string) (map[string]wikiDataProviderDefinition,
 			if def.ItemsPerColumn <= 0 {
 				return nil, fmt.Errorf("wiki data providers %s: provider %s items_per_column must be a positive integer", path, name)
 			}
+		case "facts":
+			if len(def.Facts.Rows) == 0 {
+				return nil, fmt.Errorf("wiki data providers %s: provider %s facts source requires rows", path, name)
+			}
+			for index, row := range def.Facts.Rows {
+				if strings.TrimSpace(row.Label) == "" {
+					return nil, fmt.Errorf("wiki data providers %s: provider %s facts row %d missing label", path, name, index+1)
+				}
+				if strings.TrimSpace(row.Value) == "" {
+					return nil, fmt.Errorf("wiki data providers %s: provider %s facts row %d missing value", path, name, index+1)
+				}
+			}
 		case "class_feats", "class_skills", "class_summary", "class_spellbook", "race_feats", "race_name_forms":
 			if len(def.ClassFeats.Fields) > 0 {
 				return nil, fmt.Errorf("wiki data providers %s: provider %s class feat projections require source class_progression", path, name)
@@ -148,6 +172,8 @@ func (ctx *wikiContext) wikiDataProviderRows(name string, page wikiTemplatePage)
 			return nil, nil
 		}
 		return ctx.classProgressionRows(def.Levels, def.ClassFeats.Fields, def.Attacks, page.Key, page.Row)
+	case "facts":
+		return ctx.wikiFactRows(name, def.Facts, page)
 	case "class_feats":
 		if page.Category != "classes" {
 			return nil, nil
@@ -183,6 +209,80 @@ func (ctx *wikiContext) wikiDataProviderRows(name string, page wikiTemplatePage)
 	}
 }
 
+func (ctx *wikiContext) wikiFactRows(providerName string, cfg wikiDataProviderFactsConfig, page wikiTemplatePage) ([]map[string]any, error) {
+	out := []map[string]any{}
+	renderCtx := wikiTableRenderContext{Page: page, TableName: providerName, Path: ctx.wikiDataPath}
+	for index, spec := range cfg.Rows {
+		if strings.TrimSpace(spec.When) != "" {
+			value, err := ctx.evalWikiDataProviderTemplate(spec.When, page.Row, renderCtx)
+			if err != nil {
+				return nil, fmt.Errorf("facts provider %s row %d condition %q: %w", providerName, index+1, spec.When, err)
+			}
+			if !truthyWikiTableValue(value) {
+				continue
+			}
+		}
+		value, err := ctx.evalWikiDataProviderTemplate(spec.Value, page.Row, renderCtx)
+		if err != nil {
+			return nil, fmt.Errorf("facts provider %s row %d value %q: %w", providerName, index+1, spec.Value, err)
+		}
+		text := stringifyWikiTableValue(value)
+		if strings.TrimSpace(text) == "" || strings.TrimSpace(text) == nullValue {
+			continue
+		}
+		key := strings.TrimSpace(spec.Key)
+		if key == "" {
+			key = wikiFactKeyFromLabel(spec.Label)
+		}
+		out = append(out, map[string]any{
+			"Key":   key,
+			"Label": spec.Label,
+			"Value": text,
+		})
+	}
+	return out, nil
+}
+
+func (ctx *wikiContext) evalWikiDataProviderTemplate(template string, row map[string]any, renderCtx wikiTableRenderContext) (any, error) {
+	template = strings.TrimSpace(template)
+	if strings.HasPrefix(template, "{{") && strings.HasSuffix(template, "}}") {
+		expr := strings.TrimSpace(strings.TrimSuffix(strings.TrimPrefix(template, "{{"), "}}"))
+		parser := wikiExprParser{tokens: tokenizeWikiExpr(expr), row: row, ctx: ctx, renderCtx: renderCtx, allowMissingFields: true}
+		value, err := parser.parseComparison()
+		if err != nil {
+			return nil, err
+		}
+		if parser.peek().kind != wikiExprEOF {
+			return nil, fmt.Errorf("unexpected token %q", parser.peek().text)
+		}
+		return value, nil
+	}
+	if strings.Contains(template, "{{") {
+		return nil, fmt.Errorf("mixed literal/expression templates are not supported")
+	}
+	return template, nil
+}
+
+func wikiFactKeyFromLabel(label string) string {
+	key := strings.ToLower(strings.TrimSpace(label))
+	key = strings.Map(func(r rune) rune {
+		switch {
+		case r >= 'a' && r <= 'z':
+			return r
+		case r >= '0' && r <= '9':
+			return r
+		case r == ' ' || r == '-' || r == '_':
+			return '_'
+		default:
+			return -1
+		}
+	}, key)
+	for strings.Contains(key, "__") {
+		key = strings.ReplaceAll(key, "__", "_")
+	}
+	return strings.Trim(key, "_")
+}
+
 func validateWikiDataProviderAttacks(path, provider string, cfg wikiDataProviderAttacksConfig) error {
 	if strings.TrimSpace(cfg.Mode) == "" {
 		return nil