#include "../headers/machine.h"

using namespace std;


machine::machine() {
    registri.fill(0); //konstruktor -> vsi registri so 0 na zacetku
        
    naprave[0] = make_unique<InputDevice>(cin); //0 = std vhod
    naprave[1] = make_unique<outputDevice>(cout); //1 = std izhod
    naprave[2] = make_unique<outputDevice>(cerr); //2 = std izhod za napake
        
    for (int i = 3; i < 256; i++) { //inicializacija ostalih naprav
        string fname = "files/file" + to_string(i) + ".dat";
        naprave[i] = make_unique<fileDevice>(fname);
    }

    ukaziF2 = {
        {"ADDR", [&](int r1, int r2){setReg(r2, getReg(r1)+getReg(r2)); return true;}}, 
        {"SUBR", [&](int r1, int r2){setReg(r2, getReg(r2)-getReg(r1)); return true;}},
        {"MULR", [&](int r1, int r2){setReg(r2, getReg(r2)*getReg(r1)); return true;}},
        {"DIVR", [&](int r1, int r2){setReg(r2, getReg(r2)/getReg(r1)); return true;}},
        {"CLEAR", [&](int r1, int){setReg(r1, 0); return true; }},
        {"COMPR", [&](int r1, int r2){int v1 = getReg(r1), v2 = getReg(r2);
                                    if (v1 < v2) setSW(CC_LT);
                                    else if (v1 == v2) setSW(CC_EQ);
                                    else setSW(CC_GT);
                                    return true;}},
        {"RMO", [&](int r1, int r2){setReg(r2, getReg(r1)); return true;}},
        {"SHIFTR", [&](int r1, int n){int val = getReg(r1);setReg(r1, val >> n);return true;}},
        {"SHIFTL", [&](int r1, int n){int val = getReg(r1);setReg(r1, val << n);return true;}},
        {"TIXR", [&](int r1, int){int x = getX()+1; setX(x); int v2 = getReg(r1);
                                    if (x < v2) setSW(CC_LT);
                                    else if (x == v2) setSW(CC_EQ);
                                    else setSW(CC_GT);
                                    return true;}},
    };

    ukaziSICF3F4 = {
        {"ADD", [&](int m){setA(getA()+getWord(m)); return true;}},
        {"SUB", [&](int m){setA(getA()-getWord(m)); return true;}},
        {"MUL", [&](int m){setA(getA()*getWord(m)); return true;}},
        {"DIV", [&](int m){if(getWord(m) == 0) divisionByZero();setA(getA()/getWord(m)); return true;}},
        {"AND", [&](int m){setA(getA()&getWord(m)); return true;}},
        {"OR", [&](int m){setA(getA()|getWord(m)); return true;}},
        {"COMP", [&](int m){int a = getA(); int b = getWord(m);
                            if (a < b) setSW(CC_LT);
                            else if (a == b) setSW(CC_EQ);
                            else setSW(CC_GT);
                            return true;}},
        {"J", [&](int m){setPC(m); return true;}},
        {"JEQ", [&](int m){if (getSW() == CC_EQ){setPC(m);}
                           else {setPC(getPC()+1);} return true;}},
        {"JGT", [&](int m){if (getSW() == CC_GT) {setPC(m);}
                           else {setPC(getPC()+1);} return true;}},
        {"JLT", [&](int m){if (getSW() == CC_LT){setPC(m);}
                           else{setPC(getPC()+1);} return true;}},
        {"JSUB", [&](int m){setL(getPC()); setPC(m); return true;}},
        {"RSUB", [&](int m){setPC(getL()); return true;}},
        {"LDA", [&](int m){setA(getWord(m)); return true;}},
        {"LDB", [&](int m){setB(getWord(m)); return true;}},
        {"LDT", [&](int m){setT(getWord(m)); return true;}},
        {"LDX", [&](int m){setX(getWord(m)); return true;}},
        {"LDS", [&](int m){setS(getWord(m)); return true;}},
        {"LDL", [&](int m){setL(getWord(m)); return true;}},
        {"LDCH", [&](int m){setA(getByte(m)&0xFF); return true;}},
        {"STA", [&](int m){writeWord(m, getA()); return true;}},
        {"STB", [&](int m){setWord(m, getB()); return true;}},
        {"STT", [&](int m){setWord(m, getT()); return true;}},
        {"STX", [&](int m){setWord(m, getX()); return true;}},
        {"STL", [&](int m){setWord(m, getL()); return true;}},
        {"STS", [&](int m){setWord(m, getS()); return true;}},
        {"STCH", [&](int m){setByte(m, getA()&0xFF); return true;}}, 
        {"TIX", [&](int m){setX(getX()+1);
                           if (getX() < getWord(m)) setSW(CC_LT);
                                    else if (getX() == getWord(m)) setSW(CC_EQ);
                                    else setSW(CC_GT);
                                    return true;}},
        {"WD", [&](int m){getDevice(m).write(getA()&0xFF); return true;}},
        {"RD", [&](int m){uint8_t c = getDevice(m).read()&0xFF; setA(c); return true;}},
    };
}       
    
    //machine::getterji, setterji
    int machine::getA() {return registri[A];}
    void machine::setA(int a) {registri[A] = a & 0xFFFFFF;}
    
    int machine::getX() {return registri[X];}
    void machine::setX(int x) {registri[X] = x & 0xFFFFFF;}
    
    int machine::getL() {return registri[L];}
    void machine::setL(int l) {registri[L] = l & 0xFFFFFF;}
    
    int machine::getB() {return registri[B];}
    void machine::setB(int b) {registri[B] = b & 0xFFFFFF;}
    
    int machine::getS() {return registri[S];}
    void machine::setS(int s) {registri[S] = s & 0xFFFFFF;}
    
    int machine::getT() {return registri[T];}
    void machine::setT(int t) {registri[T] = t & 0xFFFFFF;}

    double machine::getF() {return F_val;}
    void machine::setF(double f) {F_val = f;}

    int machine::getPC() {return registri[PC];}
    void machine::setPC(int pc) {registri[PC] = pc & 0xFFFFF;}

    int machine::getSW() {return registri[SW];}
    void machine::setSW(int sw) {registri[SW] = sw;}
    
    int machine::getReg(int r) {
        return r!=6 ? registri[r] : F_val;
    }
    void machine::setReg(int r, int val) {
        if (r == 6) {
            F_val = val; 
        } else {
            registri[r] = val;
        }
    }

    int machine::getByte(int adr) {
        return  (adr <= MAX_ADRESS && adr >= 0) ? pomnilnik[adr] : throw out_of_range("Naslov je izven pomnilniškega obmocja: " + to_string(adr)); 
    }
    void machine::setByte(int adr, int val) {
        if (adr < 0 || adr > MAX_ADRESS) outOfMemoryRange(adr);
        if (val < 0 || val > 255) throw invalid_argument("Byte ima vrednost med 0 in 255.");
        pomnilnik[adr] = static_cast<uint8_t>(val);

    }

    int machine::getWord(int adr) {
        if (adr < 0 || adr + 2 > MAX_ADRESS) outOfMemoryRange(adr+2);
        
        int byte1 = pomnilnik[adr];
        int byte2 = pomnilnik[adr+1];
        int byte3 = pomnilnik[adr+2];

        return (byte1 << 16) | (byte2 << 8) | byte3;
    }

    void machine::setWord(int adr, int val) {
        if (adr < 0 || adr + 2 > MAX_ADRESS) outOfMemoryRange(adr+2);
        if (val < 0 || val > 0xFFFFFF) throw invalid_argument("Beseda mora imeti vrednost med 0 in 0xFFFFFF." + to_string(val));
        
        pomnilnik[adr] = (val >> 16) & 0xFF;  //val = 0x00123456 -> hočemo 12, val >> 16 -> 0x00000012 & 0x000000ff = 0x12
        pomnilnik[adr+1] = (val >> 8) & 0xFF;
        pomnilnik[adr+2] = (val) & 0xFF;  
    }

    int machine::readWord(int addr) {
        uint8_t b1 = getByte(addr);
        uint8_t b2 = getByte(addr + 1);
        uint8_t b3 = getByte(addr + 2);

        int value = (b1 << 16) | (b2 << 8) | b3;
        return value & 0xFFFFFF;
    }

void machine::writeWord(int addr, int value) {
    // tukaj NE mečemo invalid_argument, ampak odrežemo na 24 bitov
    int v = value & 0xFFFFFF;
    setByte(addr,     (v >> 16) & 0xFF);
    setByte(addr + 1, (v >> 8)  & 0xFF);
    setByte(addr + 2,  v        & 0xFF);
}


    Device& machine::getDevice(uint8_t dev) {
        if (dev > 255) 
            throw out_of_range("Naprava ne obstaja, izberite napravo med 0 in 255");

        if (!naprave[dev])
            throw runtime_error("Naprava ni inicializirana");

        return *naprave[dev]; //rabmo returnat pointer, ker naprave so shranjene kakor unique pointerji
    }

    void machine::setDevice(uint8_t num, unique_ptr<Device> dev) {
        if (num > 255)
            throw out_of_range("Naprava ne obstaja, izberite napravo med 0 in 255");

        naprave[num] = move(dev);
    }

    void machine::setFileDevice(uint8_t num, const string& filename) {
        if (num <= 2 || num > 255) {
            throw out_of_range("Samo naprave med 3 in 255 imajo lahko poljubno ime");
        }
        naprave[num] = make_unique<fileDevice>(filename);
    }

    /*Ha_rel 000000 00004D 
    T 000000(zacetek) 1E(dolzina) 6F(byte) 20 44 77 20 44 90 40 90 50 0F 20 2B 01 00 00 90 40 94 50 0F 20 24 01 00 00 90 40 98 50
    T 00001E 1A 0F202001000090409C500F20136B2010985394347F200F3F2FFD
    T 000047 06 00001400000A
    E 000000 <- zacetek programa
    */

    void machine::loadObj(const string& path) {
        ifstream file(path);
        
        if (!file.is_open()) {
            throw runtime_error("Ne morem odpreti OBJ datoteke: " + path);
        }

        string line;
        program_end = 0;  // reset
        program_start = 0;

        cout << "Nalagam OBJ: " << path << endl;

        while (getline(file, line)) {
            if (line.empty()) continue;

            char type = line[0];

            if (type == 'H') {
                string startHex = line.substr(7, 6);
                string lenHex   = line.substr(13, 6);
                int start = stoi(startHex, nullptr, 16);
                int len   = stoi(lenHex, nullptr, 16);

                program_start = start;
                program_end = start;              
            } else if (type == 'T') {
                string startHex = line.substr(1, 6);
                string lenHex   = line.substr(7, 2);
                string data     = line.substr(9);

                int start = stoi(startHex, nullptr, 16);
                int len   = stoi(lenHex, nullptr, 16);

                cout << "Nalozil " << len << " bajtou na " << hex << start << dec << endl;

                for (int i = 0; i < len; i++) {
                    string byteHex = data.substr(i * 2, 2);
                    uint8_t value = stoi(byteHex, nullptr, 16);
                    setByte(start + i, value);
                }

                program_end = max(program_end, start + len);
            } else if (type == 'E') {
                if (line.size() > 1) {
                    string entryHex = line.substr(1);
                    program_start = stoi(entryHex, nullptr, 16);
                }

                setPC(program_start);

                cout << "Zacetek programa = 0x" << hex << program_start << dec << endl;
            }
        }
        file.close();
    }

    int machine::getUN(int n, int i, int x, int b, int p, int e, int disp) {
        int UN; 

        //F4 20b
        if (e == 1) {
            UN = disp & 0xFFFFF;
        }
        //SIC 15b
        else if (n == 0 && i == 0) {
                UN = disp & 0x7FFF;
        }
        //F3
        else {
            if (p == 1) {
                UN = (getPC() + disp) & 0xFFFFF;
            } else if (b == 1) {
                UN = (getB() + disp) & 0xFFFFF;
            } else {
                UN = disp & 0xFFFFF;
            }
        }

        //indeksno se lahko povsod pojavi
        if (x == 1) {
            UN = (UN + getX()) & 0xFFFFF;
        }
        //immediate -> vrnemo kr vrednost npr #0xb000
        if (n == 0 && i == 1) {
            return disp;
        }

        //UN je pointer na uporabni naslov
        if (n == 1 && i == 0) {
            return readWord(UN);
        }

        //enostavnu
        return UN;
    }

    void machine::outOfMemoryRange(int memory) {
        throw out_of_range("Naslov je izven pomnilniškega obmocja: " + to_string(memory));
    }

    void machine::notImplemented(const string& mnemonic) {
        throw runtime_error("Mnemonic ni implementiran: " + mnemonic);
    }

    void machine::invalidOpcode (int opcode) {
        throw invalid_argument("Opcode ne obstaja: " + to_string(opcode) + ".");
    }

    void machine::invalidAdressing() {
        throw invalid_argument("Ta način naslavljanja ni podprt.");
    }

    void machine::invalidRegister(const string& mnemonic, int r1, int r2) {
        throw invalid_argument("Neveljaven register v ukazu" + mnemonic + " r1 = " + to_string(r1) + " r2 = " + to_string(r2));
    }

    void machine::divisionByZero() {
        throw invalid_argument("Deljenje z 0 ni dovoljeno!");
    }

    uint8_t machine::fetch() {
        return machine::getByte(registri[PC]++);
    }

    bool machine::execute() {
        //cout << "[EXECUTE] PC = " << hex << getPC() << endl;

        int oldPC = getPC();  // PC pred fetchom

        uint8_t opcode8 = fetch();
        uint8_t opcode6 = opcode8 & 0xFC;

        //cout << "Fetched opcode8=" << hex << int(opcode8)
          //      << " opcode6=" << int(opcode6) << dec << endl;

        auto it = Opcode::OPCODES.find(opcode6);
        if (it == Opcode::OPCODES.end()) {
            invalidOpcode(opcode6);
            cout << "Narobe opcode\n";
            return false;
        }

        InstructionInfo ii = it->second;
        bool uspesno = false;

        switch (ii.format) {
            case 1:
                uspesno = execF1(opcode8, ii.mnemonic);
                break;

            case 2: {
                uint8_t b2 = fetch(); 
                uspesno = execF2(opcode8, b2, ii.mnemonic);
                break;
            }

            case 3: {
                uint8_t b2 = fetch(); 
                uint8_t b3 = fetch();
                uspesno = execSIC_F3_F4(opcode8, b2, b3, ii.mnemonic);
                break;
            }
            default:
                cout << "format not found\n";
                return false;
        }

        if (!uspesno) {
            cout << "[EXEC] STOP at PC=" << hex << getPC() << " opcode=" << int(opcode8) << dec << endl;
            return false;
        }

        //konec programa
        if (getPC() >= program_end || getPC() == oldPC) {
            cout << "END OF PROGRAM at PC=0x" << hex << getPC() << dec << endl;
            return false;
        }

        return true;
    }


    bool machine::execF1(uint8_t opcode, const string& mnemonic){
        //FIX, FLOAT, HIO, TIO, SIO, NORM
        auto it = Opcode::OPCODES.find(opcode);
        InstructionInfo ii = it->second;
        string name = ii.mnemonic;
        
        if (name == "FIX") {
            setA(static_cast<int>(getF()));
            return true;
        } else if (name == "FLOAT") {
            setF(static_cast<double>(getA()));
            return true;
        } else if (name == "HIO") {
            //halt I/0 na kanalu (A)
            return true;
        } else if (name == "TIO") {
            //test I/O na kanalu (A)
            return true;  
        } else if (name == "SIO") {
            //start I/O na kanalu (A), adress kanala je dan na (S)
            return true;
        } else if (name == "NORM") {
            //normalizirej (F)
            return true;
        } else {
            cout << "Izvajanje F1 neuspesno" + mnemonic + "\n";
            return false;
        }
        
    }


    bool machine::execF2(uint8_t opcode, uint8_t operand, const string& mnemonic){
        uint8_t r1 = (operand & 0xF0) >> 4;   
        uint8_t r2 = (operand & 0x0F);

        auto it = ukaziF2.find(mnemonic);
        if (it == ukaziF2.end()) {
            notImplemented(mnemonic);
            return false;
        }

        if (r1 > 9 || r2 > 9) { // r1<0, r2<0 pri uint8_t itak nista možna
            invalidRegister(mnemonic, r1, r2);
            return false;
        }

        bool ok = it->second(r1, r2);
        
        if (!ok) {
            cout << "Izvajanje F2 neuspesno, ukaz: " << mnemonic << "\n";
            return false;
        }

        return true;
    }


    bool machine::execSIC_F3_F4(uint8_t byte1, uint8_t byte2, uint8_t byte3, const string& mnemonic) {
        uint8_t n = (byte1 >> 1) & 1;   
        uint8_t i = byte1 & 1;          
        uint8_t x = (byte2 >> 7) & 1;
        uint8_t b = (byte2 >> 6) & 1;
        uint8_t p = (byte2 >> 5) & 1;
        uint8_t e = (byte2 >> 4) & 1;

        int disp = 0;
        int UN   = 0;

        auto it = ukaziSICF3F4.find(mnemonic);
        if (it == ukaziSICF3F4.end()) {
            notImplemented(mnemonic);
            return false;
        }

        /*cout << "EXEC: " << mnemonic
                << " n=" << int(n)
                << " i=" << int(i)
                << " x=" << int(x)
                << " b=" << int(b)
                << " p=" << int(p)
                << " e=" << int(e)
                << " byte2=" << hex << int(byte2)
                << " byte3=" << hex << int(byte3)
                << dec << "\n";*/
        //SIC
        if (n == 0 && i == 0) {
            disp = ((byte2 & 0x7F) << 8) | byte3;  
            UN   = getUN(0, 0, x, 0, 0, 0, disp);
        }
        //F4
        else if (e == 1) {
            uint8_t byte4 = fetch();
            disp = ((byte2 & 0x0F) << 16) | (byte3 << 8) | byte4;
            UN   = getUN(n, i, x, b, p, 1, disp);
        }
        //F3
        else {
            disp = ((byte2 & 0x0F) << 8) | byte3; 
            //sign extension
            if (disp & 0x800) {
                disp |= 0xFFFFF000;  
            }
            UN = getUN(n, i, x, b, p, 0, disp);
        }

        //cout << "operand=" << disp << "  UN=" << hex << UN << dec << "\n";

        bool ok = it->second(UN);
        if (!ok) {
            cout << "Izvajanje SIC/F3/F4 neuspesno, ukaz: " << mnemonic << "\n";
            return false;
        }

        return true;
    }