import React, { useState, useEffect } from "react";
import "../scss/components/_assignment.scss";

const AssignmentPage = () => {
  const [assignmentId, setAssignmentId] = useState("");
  const [studentName, setStudentName] = useState("");
  const [campID, setCampID] = useState("");
  const [programID, setProgramID] = useState("");
  const [appName, setAppName] = useState("");
  const [qrCodeNumber, setQrCodeNumber] = useState("");
  const [password, setPassword] = useState("");
  const [description, setDescription] = useState("");
  const [file, setFile] = useState(null);

  const [projects, setProjects] = useState([]);
  const [showModal, setShowModal] = useState(false);
  const [editingIndex, setEditingIndex] = useState(null);

  const [user, setUser] = useState([]);

  const VITE_ASSIGNMENT_URL = import.meta.env.VITE_ASSIGNMENT_URL;
  const authUrl = import.meta.env.VITE_AUTH_URL;
  const [searchTerm, setSearchTerm] = useState("");
  const [showPassword, setShowPassword] = useState(false);
  const [loading, setLoading] = useState(false);

  useEffect(() => {
    document.title = "Assignment";
    getCurrentUser();
    fetchAssignments();
  }, []);

  useEffect(() => {
    if (!appName) return; // Don't alert for empty name
    const timer = setTimeout(() => {
      fetch(`${VITE_ASSIGNMENT_URL}/instructor/checkAssignmentByAppName/${appName}`)
        .then((response) => {
          if (!response.ok) {
            throw new Error("Failed to fetch assignment by app name");
          }
          return response.json();
        })
        .then((data) => {
          if (data.exists) {
            alert("This app name already exists. Please choose a different one.");
          }
        })
        .catch((error) => {
          console.error("Error fetching assignment by app name:", error);
        });
    }, 1000); // 1 second delay

    return () => clearTimeout(timer); // Clear timeout on name change
  }, [appName]);

  useEffect(() => {
    if (!qrCodeNumber) return; // Don't alert for empty QR code number
    console.log("Checking QR code number:", qrCodeNumber); // Added console log
    const timer = setTimeout(() => {
      fetch(`${VITE_ASSIGNMENT_URL}/instructor/checkAssignmentByQRCode/${qrCodeNumber}`)
      .then((response) => {
      if (!response.ok) {
      throw new Error("Failed to fetch assignment by QR code number");
      }
      return response.json();
      })
      .then((data) => {
      console.log("QR code fetch result:", data); // Added console log
      if (data.exists) {
        alert("This QR code number already exists. Please choose a different one.");
      }
      })
      .catch((error) => {
      console.error("Error fetching assignment by QR code number:", error);
      });
    }, 1000); // 1 second delay

    return () => clearTimeout(timer); // Clear timeout on QR code number change
    }, [qrCodeNumber]);

  const getCurrentUser = async () => {
    try {
      const authResponse = await fetch(`${authUrl}/auth/current_user`, {
        credentials: "include",
      });

      const user = await authResponse.json();
      setUser(user);
    } catch (error) {
      console.error("Error fetching current user:", error);
    }
  };

  const fetchAssignments = async () => {
    try {
      // if (user) {
      // console.log("Current user:", user, `${VITE_ASSIGNMENT_URL}/instructor/list/${user.userId}`);
      // const res = await fetch(`${VITE_ASSIGNMENT_URL}/instructor/list/${user.userId}`, {
      //   // credentials: "include",
      // });
      //replace this with commented code above to get the instructor id from the auth service
      const res = await fetch(`${VITE_ASSIGNMENT_URL}/instructor/list/9`, {
        // credentials: "include",
      });

      if (!res.ok) throw new Error("Failed to fetch");
      const data = await res.json();

      // Optional: Remove duplicate assignment IDs if needed
      const unique = Array.from(
        new Map(data.map((item) => [item.assignmentid, item])).values()
      );

      setProjects(unique);
      // }
    } catch (error) {
      console.error("Error fetching assignments:", error);
    }
  };

  const resetForm = () => {
    setStudentName("");
    setCampID("");
    setProgramID("");
    setPassword("");
    setDescription("");
    setFile(null);
    setEditingIndex(null);
  };

  const handleSubmit = async (e) => {
    e.preventDefault();

    if (!user.userId) return alert("Please login to submit an assignment.");

    //Create the form data needed for both create and edit
    const formData = new FormData();
    formData.append("studentname", studentName);
    formData.append("campid", campID);
    formData.append("programid", programID);
    formData.append("qrcodenumber", qrCodeNumber);
    formData.append("password", password);
    formData.append("description", description);

    setTimeout(() => {
      if (editingIndex !== null) {
        const updatedProjects = [...projects];
        updatedProjects[editingIndex] = newProject;
        setProjects(updatedProjects);
      } else {
        setProjects([...projects, newProject]);
      }

      alert(editingIndex !== null ? "Assignment updated!" : "Assignment submitted!");
      resetForm();
      setShowModal(false);
      setLoading(false);
    }, 2000);
    if (editingIndex !== null) {
      //edit mode
      await fetch(`${VITE_ASSIGNMENT_URL}/instructor/update/${assignmentId}`, {
        method: "PUT",
        body: formData,
      })
        .then((response) => {
          
          if (!response.ok) {
            console.error("Failed to edit assignment:", response.statusText);
            throw new Error("Failed to edit assignment");
          }
          return response.json();
        })
        .then((data) => {
          console.log("Assignment edited successfully:", data);
        })
        .catch((error) => {
          console.error("Error submitting assignment:", error);
          alert(`Failed to submit assignment. ${error.message}`);
        });
    } else {
      //create mode
      formData.append("instructorid", 9);
      formData.append("appname", appName);

      if (file) {
        formData.append("file", file, file.name);
      } else {
        throw new Error("Failed to submit assignment: file not found.");
      }

      await fetch(`${VITE_ASSIGNMENT_URL}/instructor/create`, {
        method: "POST",
        body: formData,
      })
        .then((response) => {
          if (!response.ok) {
            console.error("Failed to submit assignment:", response.statusText);
            throw new Error("Failed to submit assignment");
          }
          return response.json();
        })
        .then((data) => {
          console.log("Assignment submitted successfully:", data);
        })
        .catch((error) => {
          console.error("Error submitting assignment:", error);
          alert(`Failed to submit assignment. ${error.message}`);
        });
    }

    alert(
      editingIndex !== null ? "Assignment updated!" : "Assignment submitted!"
    );

    fetchAssignments(); // Refresh the assignments list
    resetForm();
    setShowModal(false);
  };

  const handleEdit = (index) => {
    const project = projects[index];
    setAssignmentId(project.assignmentid || project.assignmentId || "");
    setAppName(project.appname || project.appName || "");
    setQrCodeNumber(project.qrcodenumber || project.qrCodeNumber || "");
    setPassword(project.passwordhash || project.password || "");
    setStudentName(project.studentname || project.studentName || "");
    setCampID(project.campid || project.campID || "");
    setProgramID(project.programid || project.programID || "");
    setDescription(project.description || "");
    setFile(null);
    setEditingIndex(index);
    setShowModal(true);
  };

  const handleDelete = (index) => {
    const project = projects[index];
    if (window.confirm("Are you sure you want to delete this assignment?")) {
      fetch(`${VITE_ASSIGNMENT_URL}/instructor/delete/${project.assignmentid}`, {
        method: "DELETE",
      })
        .then((response) => {
          if (!response.ok) {
            console.error("Failed to delete assignment:", response.statusText);
            throw new Error("Failed to delete assignment");
          }
          return response.json();
        })
        .then((data) => {
          console.log("Assignment deleted successfully:", data);
          alert("Assignment deleted successfully!");
          fetchAssignments(); // Refresh the assignments list
        })
        .catch((error) => {
          console.error("Error deleting assignment:", error);
          alert(`Failed to delete assignment. ${error.message}`);
        });
    }
  };

  return (
    <div className="assignment-page">
      <div className="assignment-header-box">
        <h2>Assignments</h2>
        <button
          onClick={() => {
            resetForm();
            setShowModal(true);
          }}
        >
          ➕ Add New
        </button>
      </div>

      <div className="assignment-search-box">
        <input
          type="text"
          placeholder="🔍︎ Search"
          value={searchTerm}
          onChange={(e) => setSearchTerm(e.target.value)}
        />
      </div>

      <div className="assignment-search-box">
        <input
          type="text"
          placeholder="🔍︎ Search"
          value={searchTerm}
          onChange={(e) => setSearchTerm(e.target.value)}
        />
      </div>

      {showModal && (
        <div className="modal-overlay">
          <div className="modal">
            <h3>
              {editingIndex !== null ? "Edit Assignment" : "New Assignment"}
            </h3>
            <form onSubmit={handleSubmit}>
              <div>
                <label>Student Name</label>
                <input
                  type="text"
                  value={studentName}
                  onChange={(e) => setStudentName(e.target.value)}
                  required
                />
              </div>

              <div>
                <label>Camp ID</label>
                <input
                  type="number"
                  value={campID}
                  onChange={(e) => setCampID(e.target.value)}
                  required
                />
              </div>

              <div>
                <label>Program ID</label>
                <input
                  type="number"
                  value={programID}
                  onChange={(e) => setProgramID(e.target.value)}
                  required
                />
              </div>

              <div>
                <label>App Name</label>
                <input
                  type="text"
                  value={appName}
                  onChange={(e) => setAppName(e.target.value)}
                  required
                  disabled={editingIndex !== null}
                  s
                />
              </div>

              <div>
                <label>Password</label>
                <input type="password" value={password} onChange={(e) => setPassword(e.target.value)} required />
              </div>

              <div>
                <label>Password</label>
                <input
                  type="password"
                  value={password}
                  onChange={(e) => setPassword(e.target.value)}
                  required
                />
              </div>

              <div>
                <label>Description</label>
                <textarea
                  value={description}
                  onChange={(e) => setDescription(e.target.value)}
                  required
                ></textarea>
              </div>

              <div>
                <label>File Upload (optional)</label>
                <input type="file" onChange={(e) => setFile(e.target.files[0])} />
              </div>

              <div className="modal-buttons">
                <button type="submit">{editingIndex !== null ? "Update" : "Submit"}</button>
                <button type="button" onClick={() => { resetForm(); setShowModal(false); }}>Cancel</button>
              </div>
            </form>
          </div>
        </div>
      )}

      {projects.length > 0 && (
        <div className="project-list">
          {projects.map((project, index) => (
            <div key={index} className="project-item">
              <div className="project-meta">
                <strong>Student Name:</strong> {project.studentname || project.studentName} |{" "}
                <strong>CampID:</strong> {project.campid || project.campID} |{" "}
                <strong>ProgramID:</strong> {project.programid || project.programID}
              </div>

              {project.title && <h4>{project.title}</h4>}
              {project.description && <p>{project.description}</p>}
              {project.fileName && <p><strong>Uploaded File:</strong> {project.fileName}</p>}

              {project.assignmenturl && (
                <p>
                  <a
                    href={project.assignmenturl}
                    target="_blank"
                    rel="noopener noreferrer"
                  >
                    View Assignment
                  </a>
                </p>
              )}
              {project.originalfile && (
                <p>
                  <a
                    href={project.originalfile}
                    target="_blank"
                    rel="noopener noreferrer"
                  >
                    Original File
                  </a>{" "}
                  |{" "}
                  <a
                    href={project.editablefile}
                    target="_blank"
                    rel="noopener noreferrer"
                  >
                    Editable File
                  </a>
                </p>
              )}

                <div className="action-buttons">
                  <button onClick={() => handleEdit(index)}>✏️ View Edit</button>
                  <button onClick={() => handleDelete(index)}>🗑️ Delete</button>
                  <button onClick={() => alert("QR feature coming soon!")}>🧮 Editor</button>
                </div>
              </div>
            ))}
        </div>
      )}
    </div>
  );
};

export default AssignmentPage;
