class ServersPage {
  constructor() {
    this.form = document.getElementById("server-form");
    this.serverIdInput = document.getElementById("server-id");
    this.serverNameInput = document.getElementById("server-name");
    this.serverHostInput = document.getElementById("server-host");
    this.clearFormBtn = document.getElementById("clear-form-btn");
    this.serversList = document.getElementById("servers-list");
    this.serversCount = document.getElementById("servers-count");

    this.init();
  }

  init() {
    this.form?.addEventListener("submit", (event) => {
      event.preventDefault();
      this.saveServer();
    });

    this.clearFormBtn?.addEventListener("click", () => this.resetForm());
    this.renderServers();
  }

  saveServer() {
    const name = this.serverNameInput?.value.trim() || "";
    const host = normalizeHost(this.serverHostInput?.value || "");

    if (!name || !host) {
      return;
    }

    const existingId = this.serverIdInput?.value || "";
    const servers = loadServers();

    if (existingId) {
      const index = servers.findIndex((server) => server.id === existingId);
      if (index >= 0) {
        servers[index] = { ...servers[index], name, host };
      }
      saveServers(servers);
      setActiveServerId(existingId);
    } else {
      const newServer = {
        id: generateServerId(),
        name,
        host
      };
      servers.push(newServer);
      saveServers(servers);
      setActiveServerId(newServer.id);
    }

    this.resetForm();
    this.renderServers();
  }

  editServer(serverId) {
    const server = getServerById(serverId);
    if (!server) {
      return;
    }

    this.serverIdInput.value = server.id;
    this.serverNameInput.value = server.name;
    this.serverHostInput.value = server.host;
  }

  deleteServer(serverId) {
    const servers = loadServers().filter((server) => server.id !== serverId);
    saveServers(servers);
    clearServerCaches(serverId);

    const activeServerId = getActiveServerId();
    if (activeServerId === serverId) {
      if (servers.length > 0) {
        setActiveServerId(servers[0].id);
      } else {
        localStorage.removeItem(ACTIVE_SERVER_KEY);
      }
    }

    this.renderServers();
  }

  selectServer(serverId) {
    setActiveServerId(serverId);
    this.renderServers();
  }

  openAvailable(serverId) {
    window.location.href = buildServerUrl("/models-available", serverId);
  }

  openRunning(serverId) {
    window.location.href = buildServerUrl("/models-running", serverId);
  }

  resetForm() {
    this.serverIdInput.value = "";
    this.serverNameInput.value = "";
    this.serverHostInput.value = "";
  }

  renderServers() {
    const servers = loadServers();
    const activeServerId = getActiveServerId();

    if (this.serversCount) {
      this.serversCount.textContent = `${servers.length} server${servers.length === 1 ? "" : "s"}`;
    }

    if (!this.serversList) {
      return;
    }

    if (servers.length === 0) {
      this.serversList.innerHTML = `
        <div class="text-center py-10 text-gray-400 border border-dashed border-gray-600 rounded-lg">
          No servers configured yet. Add your first Ollama endpoint in the control panel.
        </div>
      `;
      return;
    }

    this.serversList.innerHTML = servers
      .map((server) => {
        const isActive = server.id === activeServerId;
        return `
          <div class="bg-gray-700 border ${isActive ? "border-purple-500" : "border-gray-600"} rounded-lg p-4">
            <div class="flex flex-col md:flex-row md:items-center md:justify-between gap-4">
              <div>
                <h3 class="text-lg font-semibold">${this.escapeHtml(server.name)}</h3>
                <p class="text-xs text-gray-300 mt-1">${this.escapeHtml(server.host)}</p>
              </div>
              <div class="flex flex-wrap gap-2">
                <button data-action="select" data-server-id="${server.id}" class="bg-gray-800 hover:bg-gray-900 px-3 py-2 rounded text-xs">${isActive ? "Selected" : "Select"}</button>
                <button data-action="available" data-server-id="${server.id}" class="bg-blue-700 hover:bg-blue-800 px-3 py-2 rounded text-xs">Available</button>
                <button data-action="running" data-server-id="${server.id}" class="bg-green-700 hover:bg-green-800 px-3 py-2 rounded text-xs">Running</button>
                <button data-action="edit" data-server-id="${server.id}" class="bg-amber-700 hover:bg-amber-800 px-3 py-2 rounded text-xs">Edit</button>
                <button data-action="delete" data-server-id="${server.id}" class="bg-red-700 hover:bg-red-800 px-3 py-2 rounded text-xs">Delete</button>
              </div>
            </div>
          </div>
        `;
      })
      .join("");

    this.bindServerActions();
  }

  bindServerActions() {
    this.serversList.querySelectorAll("button[data-action]").forEach((button) => {
      button.addEventListener("click", () => {
        const action = button.getAttribute("data-action");
        const serverId = button.getAttribute("data-server-id") || "";

        if (!serverId) {
          return;
        }

        if (action === "select") this.selectServer(serverId);
        if (action === "available") this.openAvailable(serverId);
        if (action === "running") this.openRunning(serverId);
        if (action === "edit") this.editServer(serverId);
        if (action === "delete") this.deleteServer(serverId);
      });
    });
  }

  escapeHtml(text) {
    const div = document.createElement("div");
    div.textContent = text;
    return div.innerHTML;
  }
}

document.addEventListener("DOMContentLoaded", () => {
  window.serversPage = new ServersPage();
});