package de.peeeq.wurstscript.frotty.jassAttributes;

import com.google.common.collect.Maps;
import de.peeeq.wurstscript.frotty.jassValidator.JassErrors;
import de.peeeq.wurstscript.jassAst.*;
import org.eclipse.jdt.annotation.Nullable;

import java.util.List;
import java.util.Map;

public class VariableDefinition {

    public static @Nullable JassVar get(JassExprVarRef e) {
        String varName = e.getVarName();
        Element node = e.getParent();
        while (node != null) {
            if (node instanceof JassFunction) {
                JassFunction jassFunction = (JassFunction) node;
                JassVar v = getVariableMap(jassFunction).get(varName);
                if (v != null) {
                    return v;
                }
            } else if (node instanceof JassProgs) {
                JassProgs jassProgs = (JassProgs) node;
                JassVar v = jassProgs.getGlobal(varName);
                if (v != null) {
                    return v;
                }
            }
            node = node.getParent();
        }
        // error
        JassErrors.addError("Could not find variable '" + varName + "'.", e.getLine());
        return null;
    }

    public static Map<String, JassVar> getVariableMap(JassFunction f) {
        Map<String, JassVar> result = Maps.newLinkedHashMap();
        addVarsToMap(result, f.getLocals());
        addVarsToMap(result, f.getParams());
        return result;
    }

    private static void addVarsToMap(Map<String, JassVar> result, List<? extends JassVar> vs) {
        for (JassVar v : vs) {
            JassVar oldVar = result.put(v.getName(), v);
            if (oldVar != null) {
                JassErrors.addError("Variable '" + v.getName() + "' is already declared in line " + oldVar.getLine() + ".", v.getLine());
            }
        }

    }


    public static @Nullable JassStmtSet get(JassStmtSet e) {
        String varName = e.getLeft();
        Element node = e.getParent();
        while (node != null) {
            JassVar v = null;
            if (node instanceof JassFunction) {
                JassFunction jassFunction = (JassFunction) node;
                v = getVariableMap(jassFunction).get(varName);
            } else if (node instanceof JassProgs) {
                JassProgs jassProgs = (JassProgs) node;
                v = jassProgs.getGlobal(varName);

            }
            if (v != null) {
                if (v instanceof JassArrayVar) {
                    JassErrors.addError("Variable '" + varName + "' is declared as an array.", e.getLine());
                    return null;
                } else {
                    return e;
                }
            }
            node = node.getParent();
        }
        // error

        JassErrors.addError("Could not find variable '" + varName + "'.", e.getLine());
        return null;
    }

    public static @Nullable JassStmtSetArray get(JassStmtSetArray e) {
        String varName = e.getLeft();
        Element node = e.getParent();
        while (node != null) {
            if (node instanceof JassFunction) {
                JassFunction jassFunction = (JassFunction) node;
                JassVar v = getVariableMap(jassFunction).get(varName);
                if (v != null && v instanceof JassArrayVar) {
                    return e;
                }
            } else if (node instanceof JassProgs) {
                JassProgs jassProgs = (JassProgs) node;
                JassVar v = jassProgs.getGlobal(varName);
                if (v != null && v instanceof JassArrayVar) {
                    return e;
                }
            }
            node = node.getParent();
        }
        // error
        JassErrors.addError("Could not find variable '" + varName + "'.", e.getLine());
        return null;
    }

}