package jnpf.elnService.formula;

import jnpf.elnFormula.FormulaDiagnostic;
import jnpf.elnFormula.FormulaType;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public interface FormulaValidationService {

    ValidationResult validate(FormulaValidationRequest request);

    final class FormulaValidationRequest {
        private final String expression;
        private final List<ParameterSlot> parameters;
        private final FormulaType resultType;
        private final Integer roundScale;
        private final String roundMode;

        public FormulaValidationRequest(String expression, List<ParameterSlot> parameters,
                                        FormulaType resultType, Integer roundScale, String roundMode) {
            this.expression = expression;
            this.parameters = parameters == null ? null
                    : Collections.unmodifiableList(new ArrayList<>(parameters));
            this.resultType = resultType;
            this.roundScale = roundScale;
            this.roundMode = roundMode;
        }

        public String getExpression() {
            return expression;
        }

        public List<ParameterSlot> getParameters() {
            return parameters;
        }

        public FormulaType getResultType() {
            return resultType;
        }

        public Integer getRoundScale() {
            return roundScale;
        }

        public String getRoundMode() {
            return roundMode;
        }
    }

    final class ParameterSlot {
        private final String code;
        private final String displayName;
        private final FormulaType type;

        public ParameterSlot(String code, String displayName, FormulaType type) {
            this.code = code;
            this.displayName = displayName;
            this.type = type;
        }

        public String getCode() {
            return code;
        }

        public String getDisplayName() {
            return displayName;
        }

        public FormulaType getType() {
            return type;
        }
    }

    final class ValidationResult {
        private final List<FormulaDiagnostic> diagnostics;
        private final String latex;
        private final FormulaType inferredType;

        public ValidationResult(List<FormulaDiagnostic> diagnostics, String latex,
                                FormulaType inferredType) {
            this.diagnostics = Collections.unmodifiableList(new ArrayList<>(diagnostics));
            this.latex = latex;
            this.inferredType = inferredType;
        }

        public List<FormulaDiagnostic> getDiagnostics() {
            return diagnostics;
        }

        public String getLatex() {
            return latex;
        }

        public FormulaType getInferredType() {
            return inferredType;
        }

        public boolean hasErrors() {
            for (FormulaDiagnostic diagnostic : diagnostics) {
                if (diagnostic.getSeverity() == FormulaDiagnostic.Severity.ERROR) {
                    return true;
                }
            }
            return false;
        }
    }
}