mermaid-go/pkg/renderer/pie.go

// Package renderer provides rendering functionality for pie charts
package renderer

import (
	"fmt"
	"strings"

	"mermaid-go/pkg/ast"
)

// PieRenderer renders pie charts back to mermaid syntax
type PieRenderer struct{}

// NewPieRenderer creates a new pie renderer
func NewPieRenderer() *PieRenderer {
	return &PieRenderer{}
}

// Render renders a pie chart to mermaid syntax
func (r *PieRenderer) Render(diagram *ast.PieChart) (string, error) {
	var builder strings.Builder

	// Start with diagram declaration
	builder.WriteString("pie")

	// Add showData option if present
	if diagram.Config != nil {
		if showData, ok := diagram.Config["showData"]; ok && showData == true {
			builder.WriteString(" showData")
		}
	}
	builder.WriteString("\n")

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

	// Render data slices
	for _, slice := range diagram.Data {
		// Determine if label needs quotes
		needsQuotes := strings.Contains(slice.Label, " ") ||
			strings.Contains(slice.Label, ":") ||
			strings.Contains(slice.Label, "\"")

		builder.WriteString("    ")
		if needsQuotes {
			builder.WriteString(fmt.Sprintf("\"%s\"", slice.Label))
		} else {
			builder.WriteString(slice.Label)
		}

		builder.WriteString(" : ")

		// Format value (remove .0 for whole numbers)
		if slice.Value == float64(int64(slice.Value)) {
			builder.WriteString(fmt.Sprintf("%.0f", slice.Value))
		} else {
			builder.WriteString(fmt.Sprintf("%g", slice.Value))
		}

		builder.WriteString("\n")
	}

	return builder.String(), nil
}