mermaid-go/pkg/ast/flowchart.go

// Package ast defines the Abstract Syntax Tree structures for Mermaid diagrams.
// This package mirrors the TypeScript types from mermaid.js for compatibility.
package ast

// DiagramType represents the type of mermaid diagram
type DiagramType string

const (
	DiagramTypeFlowchart    DiagramType = "flowchart"
	DiagramTypeSequence     DiagramType = "sequenceDiagram"
	DiagramTypeClassDiagram DiagramType = "classDiagram"
	DiagramTypeStateDiagram DiagramType = "stateDiagram"
	DiagramTypeERDiagram    DiagramType = "erDiagram"
	DiagramTypeUserJourney  DiagramType = "journey"
	DiagramTypeTimeline     DiagramType = "timeline"
	DiagramTypeBlock        DiagramType = "block"
	DiagramTypeGantt        DiagramType = "gantt"
	DiagramTypePie          DiagramType = "pie"
	DiagramTypeQuadrant     DiagramType = "quadrantChart"
	DiagramTypeRequirement  DiagramType = "requirementDiagram"
)

// Diagram is the base interface for all mermaid diagrams
type Diagram interface {
	Type() DiagramType
	Validate() error
}

// FlowVertexTypeParam represents valid vertex types from flow.jison
// Corresponds to FlowVertexTypeParam in mermaid.js
type FlowVertexTypeParam string

const (
	VertexTypeSquare       FlowVertexTypeParam = "square"
	VertexTypeDoubleCircle FlowVertexTypeParam = "doublecircle"
	VertexTypeCircle       FlowVertexTypeParam = "circle"
	VertexTypeEllipse      FlowVertexTypeParam = "ellipse"
	VertexTypeStadium      FlowVertexTypeParam = "stadium"
	VertexTypeSubroutine   FlowVertexTypeParam = "subroutine"
	VertexTypeRect         FlowVertexTypeParam = "rect"
	VertexTypeCylinder     FlowVertexTypeParam = "cylinder"
	VertexTypeRound        FlowVertexTypeParam = "round"
	VertexTypeDiamond      FlowVertexTypeParam = "diamond"
	VertexTypeHexagon      FlowVertexTypeParam = "hexagon"
	VertexTypeOdd          FlowVertexTypeParam = "odd"
	VertexTypeTrapezoid    FlowVertexTypeParam = "trapezoid"
	VertexTypeInvTrapezoid FlowVertexTypeParam = "inv_trapezoid"
	VertexTypeLeanRight    FlowVertexTypeParam = "lean_right"
	VertexTypeLeanLeft     FlowVertexTypeParam = "lean_left"
)

// FlowVertex represents a node in a flowchart
// Mirrors the FlowVertex interface from mermaid.js
type FlowVertex struct {
	ID               string               `json:"id"`
	Classes          []string             `json:"classes"`
	Dir              *string              `json:"dir,omitempty"`
	DomID            string               `json:"domId"`
	HaveCallback     *bool                `json:"haveCallback,omitempty"`
	LabelType        string               `json:"labelType"` // Always "text" in original
	Link             *string              `json:"link,omitempty"`
	LinkTarget       *string              `json:"linkTarget,omitempty"`
	Props            map[string]any       `json:"props,omitempty"`
	Styles           []string             `json:"styles"`
	Text             *string              `json:"text,omitempty"`
	Type             *FlowVertexTypeParam `json:"type,omitempty"`
	Icon             *string              `json:"icon,omitempty"`
	Form             *string              `json:"form,omitempty"`
	Pos              *string              `json:"pos,omitempty"` // 't' or 'b'
	Img              *string              `json:"img,omitempty"`
	AssetWidth       *int                 `json:"assetWidth,omitempty"`
	AssetHeight      *int                 `json:"assetHeight,omitempty"`
	DefaultWidth     *int                 `json:"defaultWidth,omitempty"`
	ImageAspectRatio *float64             `json:"imageAspectRatio,omitempty"`
	Constraint       *string              `json:"constraint,omitempty"` // "on" or "off"
}

// FlowText represents text content in diagrams
type FlowText struct {
	Text string `json:"text"`
	Type string `json:"type"` // Always "text"
}

// FlowEdgeStroke represents edge stroke types
type FlowEdgeStroke string

const (
	StrokeNormal    FlowEdgeStroke = "normal"
	StrokeThick     FlowEdgeStroke = "thick"
	StrokeInvisible FlowEdgeStroke = "invisible"
	StrokeDotted    FlowEdgeStroke = "dotted"
)

// FlowEdge represents a connection between vertices
// Mirrors the FlowEdge interface from mermaid.js
type FlowEdge struct {
	ID              string          `json:"id,omitempty"`
	IsUserDefinedID bool            `json:"isUserDefinedId"`
	Start           string          `json:"start"`
	End             string          `json:"end"`
	Interpolate     *string         `json:"interpolate,omitempty"`
	Type            *string         `json:"type,omitempty"`
	Stroke          *FlowEdgeStroke `json:"stroke,omitempty"`
	Style           []string        `json:"style,omitempty"`
	Length          *int            `json:"length,omitempty"`
	Text            string          `json:"text"`
	LabelType       string          `json:"labelType"` // Always "text"
	Classes         []string        `json:"classes"`
	Animation       *string         `json:"animation,omitempty"` // "fast" or "slow"
	Animate         *bool           `json:"animate,omitempty"`
}

// FlowClass represents CSS class definitions
type FlowClass struct {
	ID         string   `json:"id"`
	Styles     []string `json:"styles"`
	TextStyles []string `json:"textStyles"`
}

// FlowSubGraph represents a subgraph container
type FlowSubGraph struct {
	ID        string   `json:"id"`
	Classes   []string `json:"classes"`
	Dir       *string  `json:"dir,omitempty"`
	LabelType string   `json:"labelType"`
	Nodes     []string `json:"nodes"`
	Title     string   `json:"title"`
}

// FlowLink represents link connection details
type FlowLink struct {
	Length *int    `json:"length,omitempty"`
	Stroke string  `json:"stroke"`
	Type   string  `json:"type"`
	Text   *string `json:"text,omitempty"`
}

// Flowchart represents a complete flowchart diagram
// Mirrors the FlowDB state in mermaid.js
type Flowchart struct {
	Direction      string                   `json:"direction,omitempty"`
	Vertices       map[string]*FlowVertex   `json:"vertices"`
	Edges          []*FlowEdge              `json:"edges"`
	Classes        map[string]*FlowClass    `json:"classes"`
	SubGraphs      []*FlowSubGraph          `json:"subGraphs"`
	SubGraphLookup map[string]*FlowSubGraph `json:"subGraphLookup"`
	Tooltips       map[string]string        `json:"tooltips"`
	Version        string                   `json:"version"` // "gen-1" or "gen-2"
}

// Type returns the diagram type
func (f *Flowchart) Type() DiagramType {
	return DiagramTypeFlowchart
}

// Validate checks if the flowchart is valid
func (f *Flowchart) Validate() error {
	// Basic validation - ensure all edges reference valid vertices
	for _, edge := range f.Edges {
		if _, exists := f.Vertices[edge.Start]; !exists {
			return NewValidationError("edge references non-existent start vertex: " + edge.Start)
		}
		if _, exists := f.Vertices[edge.End]; !exists {
			return NewValidationError("edge references non-existent end vertex: " + edge.End)
		}
	}
	return nil
}

// ValidationError represents a diagram validation error
type ValidationError struct {
	Message string
}

func (e *ValidationError) Error() string {
	return "validation error: " + e.Message
}

// NewValidationError creates a new validation error
func NewValidationError(message string) *ValidationError {
	return &ValidationError{Message: message}
}

// NewFlowchart creates a new flowchart with default values
func NewFlowchart() *Flowchart {
	return &Flowchart{
		Vertices:       make(map[string]*FlowVertex),
		Edges:          make([]*FlowEdge, 0),
		Classes:        make(map[string]*FlowClass),
		SubGraphs:      make([]*FlowSubGraph, 0),
		SubGraphLookup: make(map[string]*FlowSubGraph),
		Tooltips:       make(map[string]string),
		Version:        "gen-2",
	}
}