#include "error.h"

#include <iostream>
using namespace std;

// The following are global variables from the scanner (the lex .l file)
extern int line_count;                // the line number of current token

/* static */ bool Error::m_runtime = false;
/* static */ int Error::m_num_errors = 0;

/* static */ void 
Error::error_header()
{
    if (m_runtime)
        cerr << "Runtime error: ";
    else cerr << "Semantic error on line " << line_count  << ": ";
}

/* static */ void 
Error::error(Error_type type, 
             string s1 /* = "" */, 
             string s2 /* = "" */, 
             string s3 /* = "" */
            )
{
    switch (type) 
    {
        case ANIMATION_PARAM_DOES_NOT_MATCH_FORWARD:
            error_header();
            cerr << "The animation block's parameter does not match "
                 << "the parameter specified in the forward statement."
                 << endl;
            break;
        case ANIMATION_PARAMETER_NAME_NOT_UNIQUE:
            error_header();
            cerr << "The animation parameter '" << s1
                 << "' is not a unique name.  Animation parameters must have"
                 << " names that are unique in the global name space." 
                 << endl;
            break;
        case ARRAY_INDEX_MUST_BE_AN_INTEGER:
            error_header();
                 // s2 is expected to be one of the following strings 
                 //     "A double expression"
                 //     "A string expression"
                 //     "A animation_block expression"
                 cerr << s2
                      << " is not a legal array index.  The array is '"
                      << s1 << "'.";
                 if (m_runtime)
                     cerr << "  Element '" << s1 <<"[0]' will be used instead.";
                 cerr << endl;
            break;
        case ARRAY_INDEX_OUT_OF_BOUNDS:
            error_header();
                 cerr << "Index value '" << s2
                      << "' is out of bounds for array '"
                      << s1 << "'.";
                 if (m_runtime)
                     cerr << "  Element '" << s1 <<"[0]' will be used instead.";
                 cerr << endl;
            break;
        case ASSIGNMENT_TYPE_ERROR:
            error_header();
            cerr << "Cannot assign an expression of type '" << s2 
                 << "' to a variable of type '" << s1 << "'." 
                 << endl;
            break;

        // some attributes (such as h & w in a circle) cannot be changed
        case CANNOT_CHANGE_DERIVED_ATTRIBUTE:
            error_header();
            cerr << "Cannot changed derived field '" << s1 << "' of a '" << s2 
                 << "' object.  This field is derived from other fields.  ";
            if (m_runtime)
                cerr << "The change will be ignored.";
            cerr << endl;
            break;
        case EXIT_STATUS_MUST_BE_AN_INTEGER:
            error_header();
            cerr << "Value passed to exit() must be an integer.  "
                 << "Value passed was of type '" << s1  << "'."
                 << endl;
            break;

        // this error originates from gpl.y when it finds an illegal token
        case ILLEGAL_TOKEN:
            cerr << "Syntax error on line "
                 << line_count
                 << "'" << s1 << "'" << " is not a legal token." 
                 << endl;
            break;
        case INCORRECT_CONSTRUCTOR_PARAMETER_TYPE:
            error_header();
            cerr << "Incorrect type for parameter '"
                 << s2 << "' of object " << s1  << "."
                 << endl;
            break;
        case INVALID_ARRAY_SIZE:
            error_header();
            cerr << "The array '" << s1 << "' was declared with illegal size '" 
                 << s2 << "'.  Arrays sizes must be integers of 1 or larger."
                 << endl;
            break;
        // everything but a game object is a legal LHS of assignment
        case INVALID_LHS_OF_ASSIGNMENT: 
            error_header();
            cerr << "LHS of assignment must be "
                 << "(INT || DOUBLE || STRING || ANIMATION_BLOCK)."
                 << "  Variable '" << s1 << "' is of type '"  << s2 << "'."
                 << endl;
            break;
        case INVALID_LHS_OF_MINUS_ASSIGNMENT:
            error_header();
            cerr << "LHS of minus-assignment must be (INT || DOUBLE)."
                 << "  Variable '" << s1 << "' is of type '"  << s2 << "'."
                 << endl;
            break;
        case INVALID_LHS_OF_PLUS_ASSIGNMENT:
            error_header();
            cerr << "LHS of plus-assignment must be (INT || DOUBLE || STRING)."
                 << "  Variable '" << s1 << "' is of type '"  << s2 << "'."
                 << endl;
            break;
        case INVALID_LEFT_OPERAND_TYPE:
            error_header();
            cerr << "Invalid left operand for operator '" << s1 << "'."
                 << endl;
            break;
        case INVALID_RIGHT_OPERAND_TYPE:
            error_header();
            cerr << "Invalid right operand for operator '" << s1 << "'."
                 << endl;
            break;
        case INVALID_TYPE_FOR_INITIAL_VALUE:
            error_header();
            cerr << "Incorrect type for initial value of variable '"
                 << s1 << "'." 
                 << endl;
            break;
        case INVALID_TYPE_FOR_FOR_STMT_EXPRESSION:
            error_header();
            cerr << "Incorrect type for expression in for statement."
                 << "  Expressions in for statements must be of type INT."
                 << endl;
            break;
        case INVALID_TYPE_FOR_IF_STMT_EXPRESSION:
            error_header();
            cerr << "Incorrect type for expression in an if statement."
                 << "  Expressions in if statements must be of type INT."
                 << endl;
            break;
        case INVALID_TYPE_FOR_PRINT_STMT_EXPRESSION:
            error_header();
            cerr << "Incorrect type for expression in a print statement."
                 << "  Expressions in print statements must be"
                 << " of type INT, DOUBLE, or STRING."
                 << endl;
            break;
        case INVALID_TYPE_FOR_RESERVED_VARIABLE:
            error_header();
            cerr << "Incorrect type for reserved variable '" << s1
                 << "'  It was declared with type '" << s2 
                 << "'.  It must be of type '" << s3 << "'."
                 << endl;
            break;
        case LHS_OF_PERIOD_MUST_BE_OBJECT:
            error_header();
            cerr << "Variable '" << s1 << "' is not an object."
                 << "  Only objects may be on the left of a period."
                 << endl;
            break;
        case MINUS_ASSIGNMENT_TYPE_ERROR:
            error_header();
            cerr << "Cannot -= an expression of type '" << s2 
                 << "' from a variable of type '" << s1 << "'." 
                 << endl;
            break;
        case NO_BODY_PROVIDED_FOR_FORWARD:
            error_header();
            cerr << "No body was provided for animation block '" << s1 
                 << "' which was declared in a forward statement."
                 << endl;
            break;
        case NO_FORWARD_FOR_ANIMATION_BLOCK:
            error_header();
            cerr << "There is not a forward statement for animation block '" 
                 << s1 << "'." 
                 << endl;
            break;
        // game objects are the only valid operands for near and touches
        case OPERAND_MUST_BE_A_GAME_OBJECT:
            error_header();
            cerr << "Operand '" << s1 << "' must be of type Game_object or "
                 << "inherit from Game_object."
                 << endl;
            break;
        // only called in gpl.cpp when parser finds an error
        // called from yyerror()
        case PARSE_ERROR:
            cerr << "Parse error on line "
                 << line_count 
                 << " reported by parser: " 
                 << s1 << "."
                 << endl;
            break;
        case PLUS_ASSIGNMENT_TYPE_ERROR:
            error_header();
            cerr << "Cannot += an expression of type '" << s2 
                 << "' to a variable of type '" << s1 << "'." 
                 << endl;
            break;
        case PREVIOUSLY_DECLARED_VARIABLE:
            error_header();
            cerr << "Variable '"<< s1 << "'" << " previously declared." 
                 << endl;
            break;
        case PREVIOUSLY_DEFINED_ANIMATION_BLOCK:
            error_header();
            cerr << "A statement block for the animation block '"<< s1 << "'" 
                 << " has already been defined." 
                 << endl;
            break;
        case TYPE_MISMATCH_BETWEEN_ANIMATION_BLOCK_AND_OBJECT:
            error_header();
            cerr << "The type of object '"<< s1 << "'" 
                 << " does not match the type of the parameter to the "
                 << "animation block '" << s2 << "'"
                 << endl;
            break;
        case UNDECLARED_MEMBER:
            error_header();
            cerr << "Object '" << s1 << "'"
                 << " does not contain the member variable '"
                 << s2 << "'." 
                 << endl;
            break;
        case UNDECLARED_VARIABLE:
            error_header();
            cerr << "Variable '" << s1 << "'"
                 << " was not declared before it was used." 
                 << endl;
            break;
        case UNKNOWN_CONSTRUCTOR_PARAMETER:
            error_header();
            cerr << "Class '" << s1 << "' does not have a parameter called '"
                 << s2 << "'." 
                 << endl;
            break;
        case VARIABLE_NOT_AN_ARRAY:
            error_header();
            cerr << "Variable '" << s1 << "' is not an array." 
                 << endl;
            break;
        case UNDEFINED_ERROR:
            error_header();
            cerr << "Undefined error passed to Error::error().  " 
                 << "This is probably because error.cpp was not updated "
                 << "when a new error was added to error.h."
                 << endl;
            break;
        default:
            cerr << "Unknown error sent to class Error::error()." 
                 << endl;
            break;
    }
    m_num_errors++;
}