define a DSL

lang/lang.go

@@ -0,0 +1,181 @@
+package lang
+
+import (
+	"github.com/alecthomas/participle/v2"
+)
+
+// Root AST node containing all definitions
+type AST struct {
+	Definitions []Definition `parser:"@@*"`
+}
+
+// Union type for top-level definitions
+type Definition struct {
+	Server   *Server   `parser:"@@"`
+	Entity   *Entity   `parser:"| @@"`
+	Endpoint *Endpoint `parser:"| @@"`
+	Page     *Page     `parser:"| @@"`
+}
+
+// Clean server syntax
+type Server struct {
+	Name     string          `parser:"'server' @Ident"`
+	Settings []ServerSetting `parser:"@@*"`
+}
+
+type ServerSetting struct {
+	Host *string `parser:"('host' @String)"`
+	Port *int    `parser:"| ('port' @Int)"`
+}
+
+// Clean entity syntax with better readability
+type Entity struct {
+	Name        string  `parser:"'entity' @Ident"`
+	Description *string `parser:"('desc' @String)?"`
+	Fields      []Field `parser:"@@*"`
+}
+
+// Much cleaner field syntax
+type Field struct {
+	Name         string        `parser:"@Ident ':'"`
+	Type         string        `parser:"@Ident"`
+	Required     bool          `parser:"@'required'?"`
+	Unique       bool          `parser:"@'unique'?"`
+	Index        bool          `parser:"@'indexed'?"`
+	Default      *string       `parser:"('default' @String)?"`
+	Validations  []Validation  `parser:"@@*"`
+	Relationship *Relationship `parser:"@@?"`
+}
+
+// Simple validation syntax
+type Validation struct {
+	Type  string  `parser:"'validate' @Ident"`
+	Value *string `parser:"@String?"`
+}
+
+// Clear relationship syntax
+type Relationship struct {
+	Type        string  `parser:"'relates' 'to' @Ident"`
+	Cardinality string  `parser:"'as' @('one' | 'many')"`
+	ForeignKey  *string `parser:"('via' @String)?"`
+	Through     *string `parser:"('through' @String)?"`
+}
+
+// Endpoint definitions with clean, readable syntax
+type Endpoint struct {
+	Method      string          `parser:"'endpoint' @('GET' | 'POST' | 'PUT' | 'DELETE' | 'PATCH')"`
+	Path        string          `parser:"@String"`
+	Entity      *string         `parser:"('for' @Ident)?"`
+	Description *string         `parser:"('desc' @String)?"`
+	Auth        bool            `parser:"@'auth'?"`
+	Params      []EndpointParam `parser:"@@*"`
+	Response    *ResponseSpec   `parser:"@@?"`
+	CustomLogic *string         `parser:"('custom' @String)?"`
+}
+
+// Clean parameter syntax
+type EndpointParam struct {
+	Name     string `parser:"'param' @Ident ':'"`
+	Type     string `parser:"@Ident"`
+	Required bool   `parser:"@'required'?"`
+	Source   string `parser:"'from' @('path' | 'query' | 'body')"`
+}
+
+// Response specification
+type ResponseSpec struct {
+	Type   string   `parser:"'returns' @Ident"`
+	Format *string  `parser:"('as' @String)?"`
+	Fields []string `parser:"('fields' '[' @Ident (',' @Ident)* ']')?"`
+}
+
+// Page definitions for frontend with clean syntax
+type Page struct {
+	Name        string      `parser:"'page' @Ident"`
+	Path        string      `parser:"'at' @String"`
+	Layout      string      `parser:"'layout' @Ident"`
+	Title       *string     `parser:"('title' @String)?"`
+	Description *string     `parser:"('desc' @String)?"`
+	Auth        bool        `parser:"@'auth'?"`
+	Meta        []MetaTag   `parser:"@@*"`
+	Components  []Component `parser:"@@*"`
+}
+
+// Meta tags for SEO
+type MetaTag struct {
+	Name    string `parser:"'meta' @Ident"`
+	Content string `parser:"@String"`
+}
+
+// Component definitions with endpoint references
+type Component struct {
+	Type   string          `parser:"'component' @Ident"`
+	Entity *string         `parser:"('for' @Ident)?"`
+	Config []ComponentAttr `parser:"@@*"`
+}
+
+// Component attributes and configurations
+type ComponentAttr struct {
+	Fields     *ComponentFields     `parser:"@@"`
+	Actions    *ComponentActions    `parser:"| @@"`
+	DataSource *ComponentDataSource `parser:"| @@"`
+	Style      *ComponentStyle      `parser:"| @@"`
+	Pagination *ComponentPagination `parser:"| @@"`
+	Filters    *ComponentFilters    `parser:"| @@"`
+	Validation bool                 `parser:"| @'validate'"`
+}
+
+// Component field specification
+type ComponentFields struct {
+	Fields []string `parser:"'fields' '[' @Ident (',' @Ident)* ']'"`
+}
+
+// Component actions (can reference endpoints)
+type ComponentActions struct {
+	Actions []ComponentAction `parser:"'actions' '[' @@ (',' @@)* ']'"`
+}
+
+type ComponentAction struct {
+	Name     string  `parser:"@Ident"`
+	Endpoint *string `parser:"('via' @String)?"`
+}
+
+// Data source configuration (can reference endpoints)
+type ComponentDataSource struct {
+	Endpoint string `parser:"'data' 'from' @String"`
+}
+
+// Component styling
+type ComponentStyle struct {
+	Theme   *string  `parser:"'style' @Ident"`
+	Classes []string `parser:"('classes' '[' @String (',' @String)* ']')?"`
+}
+
+// Pagination configuration
+type ComponentPagination struct {
+	PageSize *int `parser:"'pagination' ('size' @Int)?"`
+}
+
+// Filter specifications
+type ComponentFilters struct {
+	Filters []ComponentFilter `parser:"'filters' '[' @@ (',' @@)* ']'"`
+}
+
+type ComponentFilter struct {
+	Field string  `parser:"@Ident"`
+	Type  string  `parser:"'as' @('text' | 'select' | 'date' | 'number')"`
+	Label *string `parser:"('label' @String)?"`
+}
+
+func ParseInput(input string) (AST, error) {
+	parser, err := participle.Build[AST](
+		participle.Unquote("String"),
+	)
+	if err != nil {
+		return AST{}, err
+	}
+	ast, err := parser.ParseString("", input)
+	if err != nil {
+		return AST{}, err
+	}
+	return *ast, nil
+}