// C4 diagram AST structures based on C4 model
package ast

// C4Diagram represents a base C4 diagram
type C4Diagram struct {
	Title      *string        `json:"title,omitempty"`
	Elements   []*C4Element   `json:"elements"`
	Relations  []*C4Relation  `json:"relations"`
	Boundaries []*C4Boundary  `json:"boundaries"`
	Config     map[string]any `json:"config,omitempty"`
}

// C4Element represents a C4 element (Person, System, Container, Component)
type C4Element struct {
	ID          string         `json:"id"`
	Type        C4ElementType  `json:"type"`
	Name        string         `json:"name"`
	Description string         `json:"description"`
	Technology  *string        `json:"technology,omitempty"`
	Properties  map[string]any `json:"properties,omitempty"`
}

// C4ElementType represents the type of C4 element
type C4ElementType string

const (
	C4ElementPerson    C4ElementType = "person"
	C4ElementSystem    C4ElementType = "system"
	C4ElementContainer C4ElementType = "container"
	C4ElementComponent C4ElementType = "component"
	C4ElementDatabase  C4ElementType = "database"
	C4ElementQueue     C4ElementType = "queue"
	C4ElementExternal  C4ElementType = "external"
)

// C4Relation represents a relationship between C4 elements
type C4Relation struct {
	From       string         `json:"from"`
	To         string         `json:"to"`
	Label      *string        `json:"label,omitempty"`
	Technology *string        `json:"technology,omitempty"`
	Type       C4RelationType `json:"type"`
	Properties map[string]any `json:"properties,omitempty"`
}

// C4RelationType represents the type of C4 relation
type C4RelationType string

const (
	C4RelationSync      C4RelationType = "sync"
	C4RelationAsync     C4RelationType = "async"
	C4RelationWebSocket C4RelationType = "websocket"
)

// C4Boundary represents a boundary in C4 diagrams
type C4Boundary struct {
	ID          string         `json:"id"`
	Type        C4BoundaryType `json:"type"`
	Name        string         `json:"name"`
	Description *string        `json:"description,omitempty"`
	Elements    []string       `json:"elements"` // IDs of elements within this boundary
}

// C4BoundaryType represents the type of C4 boundary
type C4BoundaryType string

const (
	C4BoundarySystem    C4BoundaryType = "system"
	C4BoundaryContainer C4BoundaryType = "container"
)

// C4ContextDiagram represents a C4 Context diagram
type C4ContextDiagram struct {
	C4Diagram
}

// Type returns the diagram type
func (c *C4ContextDiagram) Type() DiagramType {
	return DiagramTypeC4Context
}

// Validate checks if the C4 Context diagram is valid
func (c *C4ContextDiagram) Validate() error {
	// Basic validation - ensure all relations reference valid elements
	elementMap := make(map[string]bool)
	for _, element := range c.Elements {
		elementMap[element.ID] = true
	}

	for _, relation := range c.Relations {
		if !elementMap[relation.From] {
			return NewValidationError("relation references non-existent element: " + relation.From)
		}
		if !elementMap[relation.To] {
			return NewValidationError("relation references non-existent element: " + relation.To)
		}
	}
	return nil
}

// NewC4ContextDiagram creates a new C4 Context diagram
func NewC4ContextDiagram() *C4ContextDiagram {
	return &C4ContextDiagram{
		C4Diagram: C4Diagram{
			Elements:   make([]*C4Element, 0),
			Relations:  make([]*C4Relation, 0),
			Boundaries: make([]*C4Boundary, 0),
			Config:     make(map[string]any),
		},
	}
}

// C4ContainerDiagram represents a C4 Container diagram
type C4ContainerDiagram struct {
	C4Diagram
}

// Type returns the diagram type
func (c *C4ContainerDiagram) Type() DiagramType {
	return DiagramTypeC4Container
}

// Validate checks if the C4 Container diagram is valid
func (c *C4ContainerDiagram) Validate() error {
	return c.C4Diagram.validate()
}

// NewC4ContainerDiagram creates a new C4 Container diagram
func NewC4ContainerDiagram() *C4ContainerDiagram {
	return &C4ContainerDiagram{
		C4Diagram: C4Diagram{
			Elements:   make([]*C4Element, 0),
			Relations:  make([]*C4Relation, 0),
			Boundaries: make([]*C4Boundary, 0),
			Config:     make(map[string]any),
		},
	}
}

// C4ComponentDiagram represents a C4 Component diagram
type C4ComponentDiagram struct {
	C4Diagram
}

// Type returns the diagram type
func (c *C4ComponentDiagram) Type() DiagramType {
	return DiagramTypeC4Component
}

// Validate checks if the C4 Component diagram is valid
func (c *C4ComponentDiagram) Validate() error {
	return c.C4Diagram.validate()
}

// NewC4ComponentDiagram creates a new C4 Component diagram
func NewC4ComponentDiagram() *C4ComponentDiagram {
	return &C4ComponentDiagram{
		C4Diagram: C4Diagram{
			Elements:   make([]*C4Element, 0),
			Relations:  make([]*C4Relation, 0),
			Boundaries: make([]*C4Boundary, 0),
			Config:     make(map[string]any),
		},
	}
}

// C4DynamicDiagram represents a C4 Dynamic diagram
type C4DynamicDiagram struct {
	C4Diagram
}

// Type returns the diagram type
func (c *C4DynamicDiagram) Type() DiagramType {
	return DiagramTypeC4Dynamic
}

// Validate checks if the C4 Dynamic diagram is valid
func (c *C4DynamicDiagram) Validate() error {
	return c.C4Diagram.validate()
}

// NewC4DynamicDiagram creates a new C4 Dynamic diagram
func NewC4DynamicDiagram() *C4DynamicDiagram {
	return &C4DynamicDiagram{
		C4Diagram: C4Diagram{
			Elements:   make([]*C4Element, 0),
			Relations:  make([]*C4Relation, 0),
			Boundaries: make([]*C4Boundary, 0),
			Config:     make(map[string]any),
		},
	}
}

// C4DeploymentDiagram represents a C4 Deployment diagram
type C4DeploymentDiagram struct {
	C4Diagram
}

// Type returns the diagram type
func (c *C4DeploymentDiagram) Type() DiagramType {
	return DiagramTypeC4Deployment
}

// Validate checks if the C4 Deployment diagram is valid
func (c *C4DeploymentDiagram) Validate() error {
	return c.C4Diagram.validate()
}

// NewC4DeploymentDiagram creates a new C4 Deployment diagram
func NewC4DeploymentDiagram() *C4DeploymentDiagram {
	return &C4DeploymentDiagram{
		C4Diagram: C4Diagram{
			Elements:   make([]*C4Element, 0),
			Relations:  make([]*C4Relation, 0),
			Boundaries: make([]*C4Boundary, 0),
			Config:     make(map[string]any),
		},
	}
}

// validate is a helper method for common C4 diagram validation
func (c *C4Diagram) validate() error {
	elementMap := make(map[string]bool)
	for _, element := range c.Elements {
		elementMap[element.ID] = true
	}

	for _, relation := range c.Relations {
		if !elementMap[relation.From] {
			return NewValidationError("relation references non-existent element: " + relation.From)
		}
		if !elementMap[relation.To] {
			return NewValidationError("relation references non-existent element: " + relation.To)
		}
	}
	return nil
}

// AddElement adds an element to the C4 diagram
func (c *C4Diagram) AddElement(element *C4Element) {
	c.Elements = append(c.Elements, element)
}

// AddRelation adds a relation to the C4 diagram
func (c *C4Diagram) AddRelation(relation *C4Relation) {
	c.Relations = append(c.Relations, relation)
}

// AddBoundary adds a boundary to the C4 diagram
func (c *C4Diagram) AddBoundary(boundary *C4Boundary) {
	c.Boundaries = append(c.Boundaries, boundary)
}

// FindElement finds an element by ID
func (c *C4Diagram) FindElement(id string) *C4Element {
	for _, element := range c.Elements {
		if element.ID == id {
			return element
		}
	}
	return nil
}

// FindBoundary finds a boundary by ID
func (c *C4Diagram) FindBoundary(id string) *C4Boundary {
	for _, boundary := range c.Boundaries {
		if boundary.ID == id {
			return boundary
		}
	}
	return nil
}