#include "services.hpp"
#include "utils/envmanager.hpp"
#include "utils/directories.hpp"
#include "templates.hpp"
#include "config.hpp"
#include "utils/utils.hpp"
#include <libassert/assert.hpp>

#include <iostream>
#include <filesystem>

namespace fs = std::filesystem;

namespace dropshell
{

#pragma message("TODO : Smart test that the service is fully valid.")
    bool SIvalid(const LocalServiceInfo &service_info)
    {
        return !service_info.service_name.empty() &&
               !service_info.template_name.empty() &&
               !service_info.local_service_path.empty() &&
               !service_info.local_template_path.empty() &&
               !service_info.user.empty();
    }

    std::vector<LocalServiceInfo> get_server_services_info(const std::string &server_name)
    {
        std::vector<LocalServiceInfo> services;

        if (server_name.empty())
            return services;

        std::vector<std::string> local_server_definition_paths = gConfig().get_local_server_definition_paths();
        if (local_server_definition_paths.empty())
        {
            error << "No local server definition paths found" << std::endl;
            info << "Run 'dropshell edit' to configure DropShell" << std::endl;
            return services;
        }

        for (const auto &server_definition_path : local_server_definition_paths)
        {
            fs::path serverpath = server_definition_path + "/" + server_name;
            if (fs::exists(serverpath)) // service is on that server...
                for (const auto &entry : fs::directory_iterator(serverpath))
                {
                    if (fs::is_directory(entry))
                    {
                        std::string dirname = entry.path().filename().string();
                        if (dirname.empty() || dirname[0] == '.' || dirname[0] == '_')
                            continue;
                        auto service = get_service_info(server_name, dirname);
                        if (!service.local_service_path.empty())
                            services.push_back(service);
                        else
                            warning << "Failed to get service info for " << dirname << " on server " << server_name << std::endl;
                    }
                } // end of for
        }

        return services;
    }

    bool get_bool_variable(const std::map<std::string, std::string> &variables, const std::string &variable_name)
    {
        auto it = variables.find(variable_name);
        if (it == variables.end())
        {
            error << "Variable " << variable_name << " not found in the service " << filenames::template_info_env << std::endl;
            return false;
        }
        return it->second == "true";
    }

    LocalServiceInfo get_service_info(const std::string &server_name, const std::string &service_name)
    {
        LocalServiceInfo service;

        if (server_name.empty() || service_name.empty())
            return LocalServiceInfo();

        service.service_name = service_name;

        service.local_service_path = localpath::service(server_name, service_name);
        if (service.local_service_path.empty())
            return LocalServiceInfo();

        // check the service directory exists.
        if (!fs::exists(service.local_service_path))
        {
            warning << "Service directory not found: " << service.local_service_path << std::endl;
            return LocalServiceInfo();
        }

        // now set the template name and path.
        std::map<std::string, std::string> variables;
        if (!get_all_service_env_vars(server_name, service_name, variables))
            return LocalServiceInfo();

        { // confirm TEMPLATE is defined.
            auto it = variables.find("TEMPLATE");
            if (it == variables.end())
            {
                error << "TEMPLATE variable not defined in service " << service_name << " on server " << server_name << std::endl;
                return LocalServiceInfo();
            }
            service.template_name = it->second;
        }

        template_info tinfo = gTemplateManager().get_template_info(service.template_name);
        if (!tinfo.is_set())
        {
            error << "Template specified '" << service.template_name << "' could not be found" << std::endl;
            return LocalServiceInfo();
        }

        // find the template path
        service.local_template_path = tinfo.local_template_path();

        { // set the user.
            auto it = variables.find("SSH_USER");
            if (it == variables.end())
            {
                error << "SSH_USER variable not defined in service " << service_name << " on server " << server_name << std::endl;
                return LocalServiceInfo();
            }
            service.user = it->second;
        }

        // set the host root and docker requirements.
        service.requires_host_root = get_bool_variable(variables, "REQUIRES_HOST_ROOT");
        service.requires_docker = get_bool_variable(variables, "REQUIRES_DOCKER");
        service.requires_docker_root = get_bool_variable(variables, "REQUIRES_DOCKER_ROOT");

        { // determine if the service template hash matches the template hash.
            auto it = variables.find("TEMPLATE_HASH");
            if (it == variables.end())
                error << "Variable TEMPLATE_HASH not found in the service " << filenames::template_info_env << std::endl;
            else
            {
                uint64_t service_template_hash = std::stoull(it->second);
                service.service_template_hash_match = (service_template_hash == tinfo.hash());
                //debug << "Service template hash: " << service_template_hash << " == " << tinfo.hash() << std::endl;
            }
        }

        return service;
    }

    std::set<std::string> get_used_commands(const std::string &server_name, const std::string &service_name)
    {
        std::set<std::string> commands;

        if (server_name.empty() || service_name.empty())
            return commands;

        auto service_info = get_service_info(server_name, service_name);
        if (service_info.local_template_path.empty())
        {
            error << "Service not found: " << service_name << std::endl;
            return commands;
        }

        // iterate over all files in the template path, and add the command name to the set.
        // commands are .sh files that don't begin with _
        for (const auto &entry : fs::directory_iterator(service_info.local_template_path))
        {
            if (fs::is_regular_file(entry) && entry.path().extension() == ".sh" && (entry.path().filename().string().rfind("_", 0) != 0))
                commands.insert(entry.path().stem().string());
        }
        return commands;
    }

    std::set<std::string> list_backups(const std::string &server_name, const std::string &service_name)
    {
        std::set<std::string> backups;

        if (server_name.empty() || service_name.empty())
            return backups;

        // need to find the template for the service.
        auto service_info = get_service_info(server_name, service_name);
        if (service_info.local_template_path.empty())
        {
            error << "Service not found: " << service_name << std::endl;
            return backups;
        }

        std::string backups_dir = localpath::backups();
        if (backups_dir.empty())
            return backups;

        if (fs::exists(backups_dir))
        {
            for (const auto &entry : fs::directory_iterator(backups_dir))
            {
                if (fs::is_regular_file(entry) && entry.path().extension() == ".tgz")
                    if (entry.path().filename().string().find(service_info.template_name) != std::string::npos)
                    {
                        backups.insert(entry.path().filename().string());
                    }
            }
        }
        return backups;
    }

    bool get_all_service_env_vars(const std::string &server_name, const std::string &service_name, std::map<std::string, std::string> &all_env_vars)
    {
        all_env_vars.clear();

        if (localpath::service(server_name, service_name).empty() || !fs::exists(localpath::service(server_name, service_name)))
        {
            error << "Service not found: " << service_name << " on server " << server_name << std::endl;
            return false;
        }

        // Lambda function to load environment variables from a file
        auto load_env_file = [&all_env_vars](const std::string &file)
        {
            if (!file.empty() && std::filesystem::exists(file))
            {
                std::map<std::string, std::string> env_vars;
                envmanager env_manager(file);
                env_manager.load();
                env_manager.get_all_variables(env_vars);
                all_env_vars.merge(env_vars);
            }
            else
                warning << "Expected environment file not found: " << file << std::endl;
        };

        // Load environment files
        load_env_file(localfile::service_env(server_name, service_name));
        load_env_file(localfile::template_info_env(server_name, service_name));

        std::string user = all_env_vars["SSH_USER"];
        if (user.empty())
        {
            error << "SSH_USER variable not defined in service " << service_name << " on server " << server_name << std::endl;
            info << "This variable definition is always required, and usually set in the "<<filenames::service_env << " file." << std::endl;
            info << "Please check " << localfile::service_env(server_name, service_name) << std::endl;
            return false;
        }

        // add in some handy variables.
        // if we change these, we also need to update agent/_allservicesstatus.sh
        all_env_vars["CONFIG_PATH"] = remotepath(server_name, user).service_config(service_name);
        all_env_vars["SERVER"] = server_name;
        all_env_vars["SERVICE"] = service_name;
        all_env_vars["AGENT_PATH"] = remotepath(server_name, user).agent();
        all_env_vars["DOCKER_CLI_HINTS"] = "false"; // turn off docker junk.

        // determine template name.
        auto it = all_env_vars.find("TEMPLATE");
        if (it == all_env_vars.end())
        {
            error << "TEMPLATE variable not defined in service " << service_name << " on server " << server_name << std::endl;
            info << "The TEMPLATE variable is required to determine the template name." << std::endl;
            info << "Please check the " << filenames::service_env << " file and the "<< filenames::template_info_env << " file in:" << std::endl;
            info << "    " << localpath::service(server_name, service_name) << std::endl
                 << std::endl;
            return false;
        }
        template_info tinfo = gTemplateManager().get_template_info(it->second);
        if (!tinfo.is_set())
        {
            error << "Template '" << it->second << "' not found" << std::endl;
            return false;
        }

        return true;
    }

} // namespace dropshell