#include "main_commands.hpp"

#include "utils/directories.hpp"
#include "utils/utils.hpp"
#include "utils/readmes.hpp"
#include "service_runner.hpp"
#include "config.hpp"
#include "templates.hpp"
#include "server_env_manager.hpp"

#include <iostream>
#include <filesystem>
#include <algorithm>

namespace dropshell {

namespace main_commands {


static const std::string magic_string = "-_-";


int init(const std::vector<std::string> &args)
{
    std::string lcd;

    if (args.size() < 3) {
        std::cerr << "Error: init command requires a directory argument" << std::endl;
        return 1;
    }
    try {
        if (!gConfig().add_local_config_directory(args[2])) 
            return 1; // error already reported

        gConfig().save_config();
        std::cout << "Config directory added: " << gConfig().get_local_config_directories().back() << std::endl;
        dropshell::create_readme_local_config_dir(gConfig().get_local_config_directories().back());
        
        if (gConfig().get_local_config_directories().size() ==1)
            std::cout << "DropShell is now initialised and you can add a server with 'dropshell create-server <server-name>'" << std::endl;
        else
        {
            std::cout << "DropShell will now use all of the following directories for configuration:" << std::endl;
            for (const auto& dir : gConfig().get_local_config_directories()) {
                std::cout << "  " << dir << std::endl;
            }
            std::cout << "You can edit the config file manually with:   dropshell edit" << std::endl;
        }
    } catch (const std::exception& e) {
        std::cerr << "Error in init: " << e.what() << std::endl;
        return 1;
    }
    return 0;
}

int restore(const std::vector<std::string> &args, bool silent)
{
    if (args.size() < 4) {
        std::cerr << "Error: not enough arguments.  dropshell restore <server> <service> <backup-file>" << std::endl;
        return 1;
    }

    std::string server_name = args[2];
    std::string service_name = args[3];
    std::string backup_file = args[4];

    auto service_info = get_service_info(server_name, service_name);
    if (service_info.local_service_path.empty()) {
        std::cerr << "Error: Service not found" << std::endl;
        return 1;
    }

    server_env_manager env(server_name);
    if (!env.is_valid()) {
        std::cerr << "Error: Invalid server environment" << std::endl;
        return 1;
    }

    std::string local_backups_dir = localpath::backups_path();
    std::string local_backup_file_path = (std::filesystem::path(local_backups_dir) / backup_file).string();

    if (! std::filesystem::exists(local_backup_file_path)) {
        std::cerr << "Error: Backup file not found at " << local_backup_file_path << std::endl;
        return 1;
    }

    // split the backup filename into parts based on the magic string
    std::vector<std::string> parts = dropshell::split(backup_file, magic_string);
    if (parts.size() != 4) {
        std::cerr << "Error: Backup file format is incompatible, - in one of the names?" << std::endl;
        return 1;
    }

    std::string backup_server_name = parts[0];
    std::string backup_template_name = parts[1];
    std::string backup_service_name = parts[2];
    std::string backup_datetime = parts[3];

    if (backup_template_name != service_info.template_name) {
        std::cerr << "Error: Backup template does not match service template. Can't restore." << std::endl;
        return 1;
    }

    std::string nicedate = std::string(backup_datetime).substr(0, 10);

    std::cout << "Restoring " << nicedate << " backup of " << backup_template_name << " taken from "<<backup_server_name<<", onto "<<server_name<<std::endl;
    std::cout << std::endl;
    std::cout << "*** ALL DATA FOR "<<server_name<<"/"<<service_name<<" WILL BE OVERWRITTEN! ***"<<std::endl;
    std::cout << std::endl;
    std::cout << "Are you sure you want to continue? (y/n)" << std::endl;
    char confirm;
    std::cin >> confirm;
    if (confirm != 'y') {
        std::cout << "Restore cancelled." << std::endl;
        return 1;
    }

    // run the restore script
    std::cout << "OK, here goes..." << std::endl;

    { // backup existing service
        std::cout << "1) Backing up existing service... " << std::flush;
        std::vector<std::string> backup_args = {"dropshell","backup",server_name, service_name};
        if (!backup(backup_args,true)) // silent=true
        {
            std::cerr << std::endl;
            std::cerr << "Error: Backup failed, restore aborted." << std::endl;
            std::cerr << "You can try using   dropshell install "<<server_name<<" "<<service_name<<"   to install the service afresh." << std::endl;
            std::cerr << "Otherwise, stop the service, create and initialise a new one, then restore to that." << std::endl;
            return 1;
        }
        std::cout << "Backup complete." << std::endl;
    }

    { // restore service from backup
        std::cout << "2) Restoring service from backup..." << std::endl;
        std::string remote_backups_dir = remotepath::backups(server_name);
        std::string remote_backup_file_path = remote_backups_dir + "/" + backup_file;

        // Copy backup file from local to server
        std::string scp_cmd = "scp -P " + env.get_SSH_PORT() + " " + quote(local_backup_file_path) + " " + env.get_SSH_USER() + "@" + env.get_SSH_HOST() + ":" + quote(remote_backup_file_path) + (silent ? " > /dev/null 2>&1" : "");
        if (!env.execute_local_command(scp_cmd)) {
            std::cerr << "Failed to copy backup file from server" << std::endl;
            return false;
        }
        env.run_remote_template_command(service_name, "restore", {remote_backup_file_path}, silent);
    }

    // healthcheck the service
    std::cout << "3) Healthchecking service..." << std::endl;
    std::string green_tick = "\033[32m✓\033[0m";
    std::string red_cross = "\033[31m✗\033[0m";    
    bool healthy= (env.run_remote_template_command(service_name, "status", {}, silent));
    if (!silent)
        std::cout << (healthy ? green_tick : red_cross) << " Service is " << (healthy ? "healthy" : "NOT healthy") << std::endl;

    return 0;
}

bool name_breaks_backups(std::string name)
{
    // if name contains -_-, return true
    return name.find("-_-") != std::string::npos;
}


        // backup the service over ssh, using the credentials from server.env (via server_env.hpp)
        // 1. run backup.sh on the server
        // 2. create a backup file with format server-service-datetime.tgz
        // 3. store it in the server's DROPSHELL_DIR/backups folder
        // 4. copy it to the local user_dir/backups folder

// ------------------------------------------------------------------------------------------------
// Backup the service.
// ------------------------------------------------------------------------------------------------
int backup(const std::vector<std::string> & args, bool silent) {
    if (args.size() < 4) {
        std::cerr << "Error: backup command requires a server name and service name" << std::endl;
        return 1;
    }

    std::string server_name = args[2];
    std::string service_name = args[3];

    auto service_info = get_service_info(server_name, service_name);
    if (service_info.local_service_path.empty()) {
        std::cerr << "Error: Service not found" << std::endl;
        return 1;
    }

    server_env_manager env(server_name);
    if (!env.is_valid()) {
        std::cerr << "Error: Invalid server environment" << std::endl;
        return 1;
    }

    const std::string command = "backup";

    if (!template_command_exists(service_info.template_name, command)) {
        std::cout << "No backup script for " << service_info.template_name << std::endl;
        return true; // nothing to back up.
    }
    
    // Check if basic installed stuff is in place.
    std::string remote_service_template_path = remotepath::service_template(server_name, service_name);
    std::string remote_command_script_file = remote_service_template_path + "/" + command + ".sh";
    std::string remote_service_config_path = remotepath::service_config(server_name, service_name);
    if (!env.check_remote_items_exist({
        remotepath::service(server_name, service_name),
        remote_command_script_file,
        remotefile::service_env(server_name, service_name)})
    )
    {
        std::cerr << "Error: Required service directories not found on remote server" << std::endl;
        std::cerr << "Is the service installed?" << std::endl;
        return false;
    }

    // Create backups directory on server if it doesn't exist
    std::string remote_backups_dir = remotepath::backups(server_name);
    if (!silent) std::cout << "Remote backups directory on "<< server_name <<": " << remote_backups_dir << std::endl;
    std::string mkdir_cmd = "mkdir -p " + quote(remote_backups_dir);
    if (!env.execute_ssh_command(mkdir_cmd)) {
        std::cerr << "Failed to create backups directory on server" << std::endl;
        return false;
    }

    // Create backups directory locally if it doesn't exist
    std::string local_backups_dir = localpath::backups_path();
    if (local_backups_dir.empty()) {
        std::cerr << "Error: Local backups directory not found - is DropShell initialised?" << std::endl;
        return false;
    }
    if (!std::filesystem::exists(local_backups_dir)) 
        std::filesystem::create_directories(local_backups_dir);

    // Get current datetime for backup filename
    auto now = std::chrono::system_clock::now();
    auto time = std::chrono::system_clock::to_time_t(now);
    std::stringstream datetime;
    datetime << std::put_time(std::localtime(&time), "%Y-%m-%d_%H-%M-%S");
    
    if (name_breaks_backups(server_name)) {std::cerr << "Error: Server name contains invalid character sequence ( -_- ) that would break backup naming scheme" << std::endl; return 1;}
    if (name_breaks_backups(service_name)) {std::cerr << "Error: Service name contains invalid character sequence ( -_- ) that would break backup naming scheme" << std::endl; return 1;}
    if (name_breaks_backups(service_info.template_name)) {std::cerr << "Error: Service template name contains invalid character sequence ( -_- ) that would break backup naming scheme" << std::endl; return 1;}

    // Construct backup filename
    std::string backup_filename = server_name + magic_string + service_info.template_name + magic_string + service_name + magic_string + datetime.str() + ".tgz";
    std::string remote_backup_file_path = remote_backups_dir + "/" + backup_filename;
    std::string local_backup_file_path = (std::filesystem::path(local_backups_dir) / backup_filename).string();

    // assert that the backup filename is valid - -_- appears exactly 3 times in local_backup_file_path.
    ASSERT(3 == count_substring(magic_string, local_backup_file_path));

    // Run backup script
    if (!env.run_remote_template_command(service_name, command, {remote_backup_file_path}, silent)) {
        std::cerr << "Backup script failed on remote server: " << remote_backup_file_path << std::endl;
        return false;
    }

    // Copy backup file from server to local
    std::string scp_cmd = "scp -P " + env.get_SSH_PORT() + " " + 
                         env.get_SSH_USER() + "@" + env.get_SSH_HOST() + ":" + 
                         quote(remote_backup_file_path) + " " + quote(local_backup_file_path) + (silent ? " > /dev/null 2>&1" : "");
    if (!env.execute_local_command(scp_cmd)) {
        std::cerr << "Failed to copy backup file from server" << std::endl;
        return false;
    }

    if (!silent) {
        std::cout << "Backup created successfully. Restore with:"<<std::endl;
        std::cout << "   dropshell restore " << server_name << " " << service_name << " " << backup_filename << std::endl;
    }
    return true;
}


} // namespace main_commands

} // namespace dropshell