import * as React from "react";
import { api } from "./api/client";
import { Chat } from "./components/Chat";
import "./App.css";

function App() {
  const [projectPath, setProjectPath] = React.useState<string | null>(null);
  const [errorMsg, setErrorMsg] = React.useState<string | null>(null);
  const [pathInput, setPathInput] = React.useState("");
  const [isOpening, setIsOpening] = React.useState(false);
  const [knownProjects, setKnownProjects] = React.useState<string[]>([]);

  React.useEffect(() => {
    api
      .getKnownProjects()
      .then((projects) => setKnownProjects(projects))
      .catch((error) => console.error(error));
  }, []);

  async function openProject(path: string) {
    if (!path.trim()) {
      setErrorMsg("Please enter a project path.");
      return;
    }

    try {
      setErrorMsg(null);
      setIsOpening(true);
      const confirmedPath = await api.openProject(path.trim());
      setProjectPath(confirmedPath);
    } catch (e) {
      console.error(e);
      const message =
        e instanceof Error
          ? e.message
          : typeof e === "string"
            ? e
            : "An error occurred opening the project.";
      setErrorMsg(message);
    } finally {
      setIsOpening(false);
    }
  }

  function handleOpen() {
    void openProject(pathInput);
  }

  async function closeProject() {
    try {
      await api.closeProject();
      setProjectPath(null);
    } catch (e) {
      console.error(e);
    }
  }

  return (
    <main
      className="container"
      style={{ height: "100vh", padding: 0, maxWidth: "100%" }}
    >
      {!projectPath ? (
        <div
          className="selection-screen"
          style={{ padding: "2rem", maxWidth: "800px", margin: "0 auto" }}
        >
          <h1>AI Code Assistant</h1>
          <p>Paste a project path to start the Story-Driven Spec Workflow.</p>
          {knownProjects.length > 0 && (
            <div style={{ marginTop: "12px" }}>
              <div style={{ fontSize: "0.9em", color: "#666" }}>
                Recent projects
              </div>
              <ul style={{ listStyle: "none", padding: 0, margin: "8px 0 0" }}>
                {knownProjects.map((project) => (
                  <li key={project} style={{ marginBottom: "6px" }}>
                    <button
                      type="button"
                      onClick={() => void openProject(project)}
                      style={{
                        width: "100%",
                        textAlign: "left",
                        padding: "8px 10px",
                        borderRadius: "6px",
                        border: "1px solid #ddd",
                        background: "#f7f7f7",
                        cursor: "pointer",
                        fontFamily: "monospace",
                        fontSize: "0.9em",
                      }}
                    >
                      {project}
                    </button>
                  </li>
                ))}
              </ul>
            </div>
          )}
          <input
            type="text"
            value={pathInput}
            placeholder="/path/to/project"
            onChange={(event) => setPathInput(event.target.value)}
            onKeyDown={(event) => {
              if (event.key === "Enter") {
                handleOpen();
              }
            }}
            style={{ width: "100%", padding: "10px", marginTop: "12px" }}
          />
          <button type="button" onClick={handleOpen} disabled={isOpening}>
            {isOpening ? "Opening..." : "Open Project"}
          </button>
        </div>
      ) : (
        <div className="workspace" style={{ height: "100%" }}>
          <Chat projectPath={projectPath} onCloseProject={closeProject} />
        </div>
      )}

      {errorMsg && (
        <div className="error-message" style={{ marginTop: "20px" }}>
          <p style={{ color: "red" }}>Error: {errorMsg}</p>
        </div>
      )}
    </main>
  );
}

export default App;