#ifndef DEF_ERRORS_H
#define DEF_ERRORS_H

#include <string>
using namespace std;

#include "tokenize.h"

/**
 * Errors
*/
enum class ErrorType {
    // Generic
    NotImplemented,
    
    // Lexing
    UnknownToken,
    IntegerTooLarge,

    // Parsing
    EmptyInput,
    InvalidSyntax,
    ExceptedLParen,
    ExpectedRParen,
    ExpectedRCurlyBracket,
    ExpectedSemicolon,
    DependentDeclaration,

    // Analysis
    UnknownType,
    TypeNotCastable,
    TypesNotComparable,
    ExpectedIntegralType,
    ExpectedArithmeticType,

    // Runtime
    UnknownIdentifier,
    AlreadyDeclaredIdentifier,
    UninitializedIdentifier,
    DivisionByZero,
    ModuloByZero,
    BreakNotWithinLoop,
    ContinueNotWithinLoop,
};

using ErrorData = variant<monostate, string>;

class UserError : public exception {
public:
    explicit UserError(ErrorType type, CodePosition pos, ErrorData data = {})
        : pos(pos), type(type), data(data) {}

    const char* what() const noexcept override {
        return "User error occured.";
    }

    string get_message(void) const;

    const CodePosition pos;
    const ErrorType type;
    const ErrorData data;
};

class SyntaxError : public UserError {
public:
    explicit SyntaxError(ErrorType type, CodePosition pos, ErrorData data = {})
        : UserError(type, pos, data) {}
};

class TypeError : public UserError {
public:
    explicit TypeError(ErrorType type, CodePosition pos, ErrorData data = {})
        : UserError(type, pos, data) {}
};

class RuntimeError : public UserError {
public:
    explicit RuntimeError(ErrorType type, CodePosition pos, ErrorData data = {})
        : UserError(type, pos, data) {}
};

class InternalError : public exception {
public:
    explicit InternalError(CodePosition pos = {})
        : pos(pos) {}

    const char* what() const noexcept override {
        return "Internal error occurred.";
    }

    const CodePosition pos;
};

/**
 * Display the line of code associated with an error, and highlight the associated part
*/
void print_error_position(vector<string> history, CodePosition pos);

/**
 * Returns the error message associated with a user error
*/
string get_error_message(const UserError& e);

#endif