main.cpp

#include <iostream>
#include <string>
#include <fstream>
#include "parser.h"
#include "simulator.h"

// Helper: print the current config file to stdout
void showConfig(const std::string& configFile) {
    std::ifstream f(configFile);
    if (!f.is_open()) {
        std::cout << "WARNING: Could not open '" << configFile << "'!\n";
        return;
    }
    std::cout << "\n--- Current Config (" << configFile << ") ---\n";
    std::string line;
    while (std::getline(f, line)) std::cout << line << "\n";
    std::cout << "--------------------------------------\n";
}

// =============================================================================
// main — Interactive CLI
//
// Mode 1: Assembly Replay (Phases 1 & 2)
//   Prompts for an .asm file, forwarding toggle, single-step toggle.
//   Behaviour identical to original Phase 1/2 simulator.
//
// Mode 2: Trace Replay (Phase 3)
//   Prompts for a trace file path.
//   All L/S addresses are treated as virtual addresses.
//   VM subsystem (TLB + Page Table) is activated automatically.
//   No forwarding/single-step prompts (trace mode always runs to completion).
// =============================================================================

int main() {
    std::cout << "==================================================\n";
    std::cout << "   RISC-V PIPELINE SIMULATOR — Phase 3 Edition    \n";
    std::cout << "   Team: __BLANK__ | CS24B055 & CS24B057          \n";
    std::cout << "==================================================\n";

    const std::string configFile = "config.txt";

    while (true) {
        // ── Mode Selection ────────────────────────────────────────────────────
        std::cout << "\nSelect mode:\n"
                  << "  [1] Assembly Mode  (Phases 1 & 2 — .asm files)\n"
                  << "  [2] Trace Replay   (Phase 3 — .trace files with VM)\n"
                  << "  [0] Exit\n"
                  << "Choice: ";

        std::string choice_str;
        std::getline(std::cin, choice_str);

        if (choice_str == "0" || choice_str == "exit" || choice_str == "quit") {
            std::cout << "Exiting simulator. Goodbye!\n";
            return 0;
        }

        bool trace_mode = (choice_str == "2");

        // ── File selection ────────────────────────────────────────────────────
        std::string inputFile;
        std::ifstream fileCheck;

        if (!trace_mode) {
            while (true) {
                std::cout << "\nEnter assembly filename (or 'back' to return): ";
                std::getline(std::cin, inputFile);
                if (inputFile == "back") break;
                fileCheck.open(inputFile);
                if (fileCheck.is_open()) { fileCheck.close(); break; }
                std::cout << "Error: File '" << inputFile << "' not found.\n";
            }
            if (inputFile == "back") continue;
        } else {
            while (true) {
                std::cout << "\nEnter trace file path (or 'back' to return):\n"
                          << "  [Hint: traces are in the phase3_traces folder]\n"
                          << "Path: ";
                std::getline(std::cin, inputFile);
                if (inputFile == "back") break;
                fileCheck.open(inputFile);
                if (fileCheck.is_open()) { fileCheck.close(); break; }
                std::cout << "Error: File '" << inputFile << "' not found.\n";
            }
            if (inputFile == "back") continue;
        }

        // ── Show config & allow modification ─────────────────────────────────
        showConfig(configFile);
        std::cout << "Edit '" << configFile
                  << "' if needed, then press [ENTER] to continue...";
        std::string dummy;
        std::getline(std::cin, dummy);

        // ── Parse input file ──────────────────────────────────────────────────
        Parser p;
        std::vector<Instruction> program;

        if (trace_mode) {
            program = p.parseTraceFile(inputFile);
            std::cout << "\n[Trace mode] Loaded " << program.size()
                      << " instructions from: " << inputFile << "\n";
        } else {
            program = p.parseFile(inputFile);
        }

        if (program.empty()) {
            std::cout << "ERROR: No instructions loaded. Check the file.\n";
            continue;
        }

        // ── Assembly-mode options (not shown in trace mode) ───────────────────
        bool enable_forwarding = true;
        bool single_step       = false;

        if (!trace_mode) {
            std::cout << "\nEnable Pipeline Forwarding? (1=ON, 0=OFF) [Default: 1]: ";
            std::string fwd_input;
            std::getline(std::cin, fwd_input);
            if (fwd_input == "0") enable_forwarding = false;

            std::cout << "Enable Single Step Execution? (y/n) [Default: n]: ";
            std::string step_input;
            std::getline(std::cin, step_input);
            if (step_input == "y" || step_input == "Y") single_step = true;
        }

        // ── Build and configure simulator ─────────────────────────────────────
        Simulator sim(program);
        sim.loadConfig(configFile);
        sim.setForwarding(enable_forwarding);
        sim.setTraceMode(trace_mode);

        // ── Run ───────────────────────────────────────────────────────────────
        std::cout << "\n==================================================\n";
        std::cout << "Executing:   " << inputFile   << "\n";
        std::cout << "Mode:        " << (trace_mode ? "Trace Replay (Phase 3)" : "Assembly") << "\n";
        std::cout << "Instructions:" << program.size() << "\n";
        if (!trace_mode) {
            std::cout << "Forwarding:  " << (enable_forwarding ? "ON" : "OFF") << "\n";
            std::cout << "Single Step: " << (single_step        ? "ON" : "OFF") << "\n";
        }
        std::cout << "==================================================\n";

        sim.run(single_step);

        std::cout << "\nSimulation complete.\n";
    }

    return 0;
}