// Package renderer provides Organization Chart rendering
package renderer

import (
	"fmt"
	"strings"

	"mermaid-go/pkg/ast"
)

// OrganizationRenderer implements Organization Chart rendering
type OrganizationRenderer struct{}

// NewOrganizationRenderer creates a new Organization renderer
func NewOrganizationRenderer() *OrganizationRenderer {
	return &OrganizationRenderer{}
}

// Render renders an Organization Chart to mermaid syntax
func (r *OrganizationRenderer) Render(diagram *ast.OrganizationDiagram) (string, error) {
	var result strings.Builder

	// Start with organization declaration
	result.WriteString("organization\n")

	// Add title if present
	if diagram.Title != nil {
		result.WriteString(fmt.Sprintf("    title %s\n", *diagram.Title))
	}

	// Render nodes in hierarchical order
	if diagram.Root != nil {
		r.renderNodeHierarchy(&result, diagram.Root, "    ")
	} else {
		// Render all nodes if no clear hierarchy
		for _, node := range diagram.Nodes {
			if node.Parent == nil { // Root nodes
				r.renderNodeHierarchy(&result, node, "    ")
			}
		}
	}

	return result.String(), nil
}

// renderNodeHierarchy renders a node and its children recursively
func (r *OrganizationRenderer) renderNodeHierarchy(result *strings.Builder, node *ast.OrganizationNode, indent string) {
	// Render current node
	result.WriteString(fmt.Sprintf("%s%s", indent, node.ID))

	if node.Name != node.ID {
		result.WriteString(fmt.Sprintf("[%s]", node.Name))
	}

	// Render children
	if len(node.Children) > 0 {
		result.WriteString("\n")
		for _, child := range node.Children {
			// Render connection
			result.WriteString(fmt.Sprintf("%s%s --> %s", indent, node.ID, child.ID))
			if child.Name != child.ID {
				result.WriteString(fmt.Sprintf("[%s]", child.Name))
			}
			result.WriteString("\n")
		}

		// Recursively render children
		for _, child := range node.Children {
			if len(child.Children) > 0 {
				r.renderNodeHierarchy(result, child, indent)
			}
		}
	} else {
		result.WriteString("\n")
	}
}