main.cpp

#include <iostream>
#include <sstream>
#include <string>
#include <vector>
#include <cctype>
#include "filesystem.hpp"

static std::string trim(const std::string& s) {
    size_t i = 0, j = s.size();
    while (i < j && std::isspace((unsigned char)s[i])) ++i;
    while (j > i && std::isspace((unsigned char)s[j-1])) --j;
    return s.substr(i, j - i);
}

static void print_help() {
    std::cout << "\n---------------------- HELP -------------------------\n";
    std::cout << "CREATE <filename>                  : Create a new file.\n";
    std::cout << "INSERT <filename> <text>           : Insert text into file.\n";
    std::cout << "UPDATE <filename> <text>           : Replace entire content of file.\n";
    std::cout << "SNAPSHOT <filename> <message>      : Create snapshot of current version.\n";
    std::cout << "ROLLBACK <filename> <versionID>    : Roll back file by given steps.\n";
    std::cout << "HISTORY <filename>                 : Show all snapshots of the file.\n";
    std::cout << "RECENT_FILES [num]                 : Show the most recently modified files.\n";
    std::cout << "BIGGEST_TREES [num]                : Show files with most versions.\n";
    std::cout << "READ <filename>                    : Show current content of file.\n";
    std::cout << "HELP                               : Show this help message.\n";
    std::cout << "EXIT                               : Quit the program.\n";
    std::cout << "-----------------------------------------------\n\n";
}

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    std::cout << "-----------------------------------------------\n";
    std::cout << "Type HELP to see available commands.\n";
    std::cout << "-----------------------------------------------\n";

    FileSystem fs;

    std::string line;
    while (std::getline(std::cin, line)) {
        line = trim(line);
        if (line.empty()) continue;

        std::istringstream iss(line);
        std::string cmd;
        iss >> cmd;

        for (char& c : cmd) c = std::toupper((unsigned char)c);
        if (cmd == "HELP"){
            print_help();
        } else if (cmd == "CREATE") {
            std::string filename; iss >> filename;
            if (filename.empty()) { std::cout << "ERROR: Missing filename\n"; continue; }
            fs.create(filename);
            std::cout << "-----------------------------------------------\n";
            std::cout << "Created " << filename << "\n";
            std::cout << "-----------------------------------------------\n";
        } else if (cmd == "READ") {
            std::string filename; iss >> filename;
            if (filename.empty()) { std::cout << "ERROR: Missing filename\n"; continue; }
            std::cout << "-----------------------------------------------\n";
            std::cout << filename << " is as follows: " << "\n";
            std::cout << "-----------------------------------------------\n";
            fs.read(filename);
            std::cout << "-----------------------------------------------\n";
        } else if (cmd == "INSERT") {
            std::string filename; iss >> filename;
            if (filename.empty()) { std::cout << "ERROR: Missing filename\n"; continue; }
            std::string rest; std::getline(iss, rest);
            rest = trim(rest);
            fs.insert(filename, rest);
            std::cout << "-----------------------------------------------\n";
            std::cout << "Inserted message into " << filename << "\n";
            std::cout << "-----------------------------------------------\n";
        } else if (cmd == "UPDATE") {
            std::string filename; iss >> filename;
            if (filename.empty()) { std::cout << "ERROR: Missing filename\n"; continue; }
            std::string rest; std::getline(iss, rest);
            rest = trim(rest);
            fs.update(filename, rest);
            std::cout << "-----------------------------------------------\n";
            std::cout << filename << " updated succesfully."<<"\n";
            std::cout << "-----------------------------------------------\n";
        } else if (cmd == "SNAPSHOT") {
            std::string filename; iss >> filename;
            if (filename.empty()) { std::cout << "ERROR: Missing filename\n"; continue; }
            std::string rest; std::getline(iss, rest);
            rest = trim(rest);
            fs.snapshot(filename, rest);
            int vid = fs.get_active_version_id(filename);
            std::cout << "-----------------------------------------------\n";
            std::cout << "Snapshot for " << filename << " saved with version ID " << vid << "\n";
            std::cout << "-----------------------------------------------\n";
        } else if (cmd == "ROLLBACK") {
            std::string filename; iss >> filename;
            if (filename.empty()) { std::cout << "ERROR: Missing filename\n"; continue; }
            std::string maybe_id;
            iss >> maybe_id;
            if (maybe_id.empty()) {
                fs.rollback(filename, /*has_id*/false, /*id*/-1);
                std::cout << "-----------------------------------------------\n";
                std::cout << "Rolled back " << filename << " successfully."<<"\n";
                std::cout << "-----------------------------------------------\n";
            } else {
                bool ok = true;
                for (char c : maybe_id) if (!std::isdigit((unsigned char)c) && !(c=='-'||c=='+')) { ok = false; break; }
                if (!ok) {
                    std::cout << "ERROR: Invalid version id\n";
                } else {
                    int id = std::stoi(maybe_id);
                    fs.rollback(filename, /*has_id*/true, id);
                    std::cout << "-----------------------------------------------\n";
                    std::cout << "Rolled back " << filename << " successfully."<<"\n";
                    std::cout << "-----------------------------------------------\n";
                }
            }
        } else if (cmd == "HISTORY") {
            std::string filename; iss >> filename;
            if (filename.empty()) { std::cout << "ERROR: Missing filename\n"; continue; }
            std::cout << "-----------------------------------------------\n";
            fs.history(filename);
            std::cout << "-----------------------------------------------\n";
        } else if (cmd == "RECENT_FILES" || cmd == "RECENT") {
            int limit = -1;
            if (cmd == "RECENT") {
                std::string next; iss >> next;
                for (char& c : next) c = std::toupper((unsigned char)c);
                if (next != "FILES") {
                    std::cout << "ERROR: Unknown command\n";
                    continue;
                }
                std::string maybe_n; iss >> maybe_n;
                if (!maybe_n.empty()) limit = std::stoi(maybe_n);
            } else {
                std::string maybe_n; iss >> maybe_n;
                if (!maybe_n.empty()) limit = std::stoi(maybe_n);
            }
            std::cout << "-----------------------------------------------\n";
            fs.recent_files(limit);
            std::cout << "-----------------------------------------------\n";
        } else if (cmd == "BIGGEST_TREES" || cmd == "BIGGEST") {
            int limit = -1;
            if (cmd == "BIGGEST") {
                std::string next; iss >> next;
                for (char& c : next) c = std::toupper((unsigned char)c);
                if (next != "TREES") {
                    std::cout << "ERROR: Unknown command\n";
                    continue;
                }
                std::string maybe_n; iss >> maybe_n;
                if (!maybe_n.empty()) limit = std::stoi(maybe_n);
            } else {
                std::string maybe_n; iss >> maybe_n;
                if (!maybe_n.empty()) limit = std::stoi(maybe_n);
            }
            std::cout << "-----------------------------------------------\n";
            fs.biggest_trees(limit);
            std::cout << "-----------------------------------------------\n";
        } else if (cmd == "EXIT") {
            break;
        } else {
            std::cout << "ERROR: Unknown command\n";
        }
    }
    return 0;
}