package no.uio.ifi.refaktor.analyze;

import static no.uio.ifi.refaktor.assertion.RefaktorAssert.assertThat;
import static org.hamcrest.CoreMatchers.notNullValue;
import no.uio.ifi.refaktor.analyze.analyzers.ExtractAndMoveMethodAnalyzer;
import no.uio.ifi.refaktor.change.changers.ExtractAndMoveMethodChanger;
import no.uio.ifi.refaktor.prefix.Prefix;
import no.uio.ifi.refaktor.prefix.PrefixSet;
import no.uio.ifi.refaktor.utils.CompilationUnitTextSelection;
import no.uio.ifi.refaktor.utils.MethodRelativeCompilationUnitTextSelection;

import org.eclipse.jdt.core.IMethod;
import org.eclipse.jdt.core.dom.IBinding;
import org.eclipse.jdt.core.dom.IVariableBinding;

public class ExtractAndMoveMethodAnalysisResult {
	private class ResultDataCalculator {
		private final ExtractAndMoveMethodAnalyzer analyzer;

		public ResultDataCalculator(ExtractAndMoveMethodAnalyzer analyzer) {
			this.analyzer = analyzer;
		}

		public boolean hasMoreThanOnePossibleTarget() {
			PrefixSet safePrefixes = analyzer.calculateSafePrefixes();
			IBinding binding = safePrefixes.toList().getFirst().getVariableBindingOfFirstExpression();
			for (Prefix prefix: safePrefixes) {
				if (!prefix.getVariableBindingOfFirstExpression().isEqualTo(binding))
					return true;
			}
			return false;
		}

		public int getTargetFrequency() {
			if (hasMoreThanOnePossibleTarget())
				; // TODO: throw exception?
			return analyzer.calculateMostFrequentPrefix().getCount();
		}

		public boolean hasNoUnfixes() {
			return analyzer.getUnfixes().isEmpty();
		}

		public String calculateOriginalTargetKey() {
			return analyzer.calculateOriginalTarget().getKey();
		}
	}

	public final CompilationUnitTextSelection textSelection;
	public final int numberOfStatementsAnalyzed;
	public final int numberOfTextSelectionsAnalyzed;
	public final IMethod method;

	private final boolean hasMoreThanOnePossibleTarget;
	private final int targetFrequency;
	private final boolean hasNoUnfixes;
	private final String originalTargetKey;

	public ExtractAndMoveMethodAnalysisResult(IMethod method, ExtractAndMoveMethodAnalyzer analyzer, CompilationUnitTextSelection textSelection, int numberOfStatementsAnalyzed, int numberOfTextSelectionsAnalyzed) {
		this.method = method;
		this.textSelection = new MethodRelativeCompilationUnitTextSelection(method, textSelection);
		this.numberOfStatementsAnalyzed = numberOfStatementsAnalyzed;
		this.numberOfTextSelectionsAnalyzed = numberOfTextSelectionsAnalyzed;
		
		ResultDataCalculator calculator = new ResultDataCalculator(analyzer);
		hasMoreThanOnePossibleTarget = calculator.hasMoreThanOnePossibleTarget();
		targetFrequency = calculator.getTargetFrequency();
		hasNoUnfixes = calculator.hasNoUnfixes();
		originalTargetKey = calculator.calculateOriginalTargetKey();
	}

	public boolean hasMoreThanOnePossibleTarget() {
		return hasMoreThanOnePossibleTarget;
	}

	public boolean hasOnlyOnePossibleTarget() {
		return !hasMoreThanOnePossibleTarget();
	}

	public int getTargetFrequency() {
		return targetFrequency;
	}

	public boolean hasNoUnfixes() {
		return hasNoUnfixes;
	}

	public boolean hasUnfixes() {
		return !hasNoUnfixes();
	}

	public IVariableBinding calculateOriginalTarget() {
		return restoreOriginalTarget();
	}
	
	private IVariableBinding restoreOriginalTarget() {
		VariableBindingFinder variableBindingFinder = new VariableBindingFinder(originalTargetKey);
		textSelection.getCoveringNode().accept(variableBindingFinder);
		assertThat(variableBindingFinder.getVariableBinding(), notNullValue());
		return variableBindingFinder.getVariableBinding();
	}

	@Override
	public String toString() {
		return "Result for '" + method.getDeclaringType().getFullyQualifiedName() + "." + method.getElementName() + "' (" + numberOfStatementsAnalyzed + " statements analyzed): < " + textSelection + " >";
	}

	public String getNewMethodName() {
		// TODO: do better
		return ExtractAndMoveMethodChanger.generateName();
	}

	public String getOriginatingMethodName() {
		return method.getDeclaringType().getFullyQualifiedName() + "." + method.getElementName();
	}

	public IMethod getMethod() {
		return method;
	}

	public CompilationUnitTextSelection getTextSelection() {
		return textSelection;
	}
}