package main

import (
	"fmt"
	"regexp"
	"strconv"
	"strings"
)

// Enhanced math expression parser
func parseMathExpression(query string) (string, bool) {
	// Clean and normalize the expression
	query = strings.ReplaceAll(query, " ", "")
	query = strings.ReplaceAll(query, ",", "")

	// Regex to match valid math expressions
	mathRegex := regexp.MustCompile(`^\d+(\.\d+)?([\+\-\*/\^]\d+(\.\d+)?)+$`)
	if !mathRegex.MatchString(query) {
		return "", false
	}

	// Operator precedence handling
	operators := []struct {
		symbol string
		apply  func(float64, float64) float64
	}{
		{"^", func(a, b float64) float64 {
			result := 1.0
			for i := 0; i < int(b); i++ {
				result *= a
			}
			return result
		}},
		{"*", func(a, b float64) float64 { return a * b }},
		{"/", func(a, b float64) float64 { return a / b }},
		{"+", func(a, b float64) float64 { return a + b }},
		{"-", func(a, b float64) float64 { return a - b }},
	}

	// Parse numbers and operators
	var tokens []interface{}
	current := ""
	for _, char := range query {
		if char >= '0' && char <= '9' || char == '.' {
			current += string(char)
		} else {
			if current != "" {
				num, _ := strconv.ParseFloat(current, 64)
				tokens = append(tokens, num)
				current = ""
			}
			tokens = append(tokens, string(char))
		}
	}
	if current != "" {
		num, _ := strconv.ParseFloat(current, 64)
		tokens = append(tokens, num)
	}

	// Evaluate expression with operator precedence
	for _, op := range operators {
		for i := 1; i < len(tokens)-1; i += 2 {
			if operator, ok := tokens[i].(string); ok && operator == op.symbol {
				left := tokens[i-1].(float64)
				right := tokens[i+1].(float64)
				result := op.apply(left, right)

				// Update tokens
				tokens = append(tokens[:i-1], tokens[i+2:]...)
				tokens = append(tokens[:i-1], append([]interface{}{result}, tokens[i-1:]...)...)
				i -= 2 // Adjust index after modification
			}
		}
	}

	// Format result
	result := tokens[0].(float64)
	if result == float64(int(result)) {
		return fmt.Sprintf("%d", int(result)), true
	}
	return fmt.Sprintf("%.2f", result), true
}