package parser

import (
	"reflect"
	"strconv"
	"strings"
)

// evaluateAllConditions checks all conditional logic
func (p *Parser) evaluateAllConditions(fieldTag *FieldTag, _ reflect.Value) bool {
	if fieldTag.Condition != nil && !p.evaluateCondition(fieldTag.Condition) {
		return false
	}

	if fieldTag.IfVariableSet != "" && !p.isVariableSet(fieldTag.IfVariableSet) {
		return false
	}

	if fieldTag.IfVariableNotSet != "" && p.isVariableSet(fieldTag.IfVariableNotSet) {
		return false
	}

	if fieldTag.IfFlag != "" && !p.flags[fieldTag.IfFlag] {
		return false
	}

	if fieldTag.IfFlagNotSet != "" && p.flags[fieldTag.IfFlagNotSet] {
		return false
	}

	if fieldTag.IfEquals != "" {
		parts := strings.Split(fieldTag.IfEquals, "=")
		if len(parts) == 2 && !p.evaluateEqualsCondition(parts[0], parts[1]) {
			return false
		}
	}

	if fieldTag.IfNotEquals != "" {
		parts := strings.Split(fieldTag.IfNotEquals, "=")
		if len(parts) == 2 && p.evaluateEqualsCondition(parts[0], parts[1]) {
			return false
		}
	}

	return true
}

// evaluateCondition evaluates conditions for conditional fields
func (p *Parser) evaluateCondition(condition *FieldCondition) bool {
	if condition.Type == "simple" {
		return p.isVariableSet(condition.Variable)
	}

	cachedValue, exists := p.resolveVariable(condition.Variable)
	if !exists {
		return false
	}

	compareValue, err := p.convertValue(condition.Value, cachedValue)
	if err != nil {
		return false
	}

	return p.compareValues(cachedValue, compareValue, condition.Operator)
}

// isVariableSet checks if a variable exists and has a truthy value
func (p *Parser) isVariableSet(variable string) bool {
	cachedValue, exists := p.resolveVariable(variable)
	if !exists {
		return false
	}
	return p.isTruthy(cachedValue)
}

// evaluateEqualsCondition checks field equality
func (p *Parser) evaluateEqualsCondition(variable, value string) bool {
	cachedValue, exists := p.resolveVariable(variable)
	if !exists {
		return false
	}

	compareValue, err := p.convertValue(value, cachedValue)
	if err != nil {
		return false
	}

	return p.compareValues(cachedValue, compareValue, "==")
}

// evaluateType2Criteria evaluates type2 criteria for alternative types with string length support
func (p *Parser) evaluateType2Criteria(criteria string) bool {
	// String length operators: !>, !<, !>=, !<=, !=
	stringLengthOps := []string{"!>=", "!<=", "!>", "!<", "!="}

	for _, op := range stringLengthOps {
		if idx := strings.Index(criteria, op); idx > 0 {
			fieldName := strings.TrimSpace(criteria[:idx])
			valueStr := strings.TrimSpace(criteria[idx+len(op):])

			cachedValue, exists := p.resolveVariable(fieldName)
			if !exists {
				return false
			}

			return p.evaluateStringLengthCondition(cachedValue, valueStr, op)
		}
	}

	// Standard comparison operators
	operators := []string{">=", "<=", ">", "<", "=="}

	for _, op := range operators {
		if idx := strings.Index(criteria, op); idx > 0 {
			fieldName := strings.TrimSpace(criteria[:idx])
			valueStr := strings.TrimSpace(criteria[idx+len(op):])

			cachedValue, exists := p.resolveVariable(fieldName)
			if !exists {
				return false
			}

			compareValue, err := p.convertValue(valueStr, cachedValue)
			if err != nil {
				return false
			}

			return p.compareValues(cachedValue, compareValue, op)
		}
	}

	return false
}

// evaluateStringLengthCondition evaluates string length conditions
func (p *Parser) evaluateStringLengthCondition(value any, lengthStr, operator string) bool {
	var stringVal string

	// Extract string value from various types
	switch v := value.(type) {
	case string:
		stringVal = v
	default:
		// Try to get string representation from struct fields
		if reflect.TypeOf(value).Kind() == reflect.Struct {
			val := reflect.ValueOf(value)
			if dataField := val.FieldByName("Data"); dataField.IsValid() && dataField.Kind() == reflect.String {
				stringVal = dataField.String()
			} else {
				return false
			}
		} else {
			return false
		}
	}

	targetLength, err := strconv.Atoi(lengthStr)
	if err != nil {
		return false
	}

	stringLength := len(stringVal)

	switch operator {
	case "!>":
		return stringLength > targetLength
	case "!<":
		return stringLength < targetLength
	case "!>=":
		return stringLength >= targetLength
	case "!<=":
		return stringLength <= targetLength
	case "!=":
		return stringLength != targetLength
	default:
		return false
	}
}

// resolveVariable resolves variables with support for array indices and complex patterns
func (p *Parser) resolveVariable(variable string) (any, bool) {
	// Handle %i patterns by replacing with current array index
	if strings.Contains(variable, "%i") {
		currentIndex := p.GetCurrentArrayIndex()
		if currentIndex >= 0 {
			variable = strings.ReplaceAll(variable, "%i", strconv.Itoa(currentIndex))
		}
	}

	// Check field cache first
	if cachedValue, exists := p.fieldCache[variable]; exists {
		return cachedValue, true
	}

	// Handle array index patterns like "header_info_mod_need_0"
	if strings.Contains(variable, "_") {
		if value, exists := p.resolveArrayIndexVariable(variable); exists {
			return value, true
		}
	}

	// Check current struct
	if p.currentStruct.IsValid() {
		if field := p.currentStruct.FieldByName(variable); field.IsValid() {
			return field.Interface(), true
		}
	}

	// Check struct stack for nested resolution
	for i := len(p.structStack) - 1; i >= 0; i-- {
		if field := p.structStack[i].FieldByName(variable); field.IsValid() {
			return field.Interface(), true
		}
	}

	return nil, false
}

// resolveArrayIndexVariable handles variables with array index suffixes
func (p *Parser) resolveArrayIndexVariable(variable string) (any, bool) {
	parts := strings.Split(variable, "_")
	if len(parts) < 2 {
		return nil, false
	}

	// Try to extract index from last part
	lastPart := parts[len(parts)-1]
	if index, err := strconv.Atoi(lastPart); err == nil {
		// Reconstruct base variable name without index
		baseVar := strings.Join(parts[:len(parts)-1], "_")

		// Look for array/slice field with this base name
		if cachedValue, exists := p.fieldCache[baseVar]; exists {
			return p.getArrayElement(cachedValue, index)
		}

		// Check current struct for array field
		if p.currentStruct.IsValid() {
			if field := p.currentStruct.FieldByName(baseVar); field.IsValid() {
				return p.getArrayElement(field.Interface(), index)
			}
		}

		// Check struct stack
		for i := len(p.structStack) - 1; i >= 0; i-- {
			if field := p.structStack[i].FieldByName(baseVar); field.IsValid() {
				return p.getArrayElement(field.Interface(), index)
			}
		}
	}

	return nil, false
}

// getArrayElement safely extracts element from array/slice
func (p *Parser) getArrayElement(value any, index int) (any, bool) {
	val := reflect.ValueOf(value)

	switch val.Kind() {
	case reflect.Slice, reflect.Array:
		if index >= 0 && index < val.Len() {
			return val.Index(index).Interface(), true
		}
	}

	return nil, false
}