from PyQt6.QtCore import Qt
from PyQt6.QtGui import QPen
from PyQt6.QtWidgets import QGraphicsView, QGraphicsScene, QPushButton, QGraphicsProxyWidget

from data.connect import connect, Department


class DepartmentGraph(QGraphicsView):
    def __init__(self, parent):
        super().__init__()
        self.scene = QGraphicsScene(self)
        self.setScene(self.scene)
        with connect() as session:
            self.departments = session.query(Department).all()

        self.pushed_button = None
        self.parent = parent

        self.is_first_button = True

        self.nodes = {}
        self.render_graph()

    def render_graph(self):
        root_departments = [d for d in self.departments if d.parent_id is None]

        x = 50
        y = 50

        for root in root_departments:
            self.add_department_node(root, x, y)
            x += 900

    def button_clicked(self):
        if self.pushed_button is not None:
            self.pushed_button.setStyleSheet('''
            QPushButton {
            background-color: rgb(228, 244, 204);
            }
            ''')

        button = self.sender()
        button.setStyleSheet('''
        QPushButton {
        background-color: #2f9836;
        }
        ''')
        self.pushed_button = button

        self.parent.select_department(button.department_id)

    def add_department_node(self, department, x, y, parent_item=None, level=0):
        button = QPushButton(department.title)
        button.department_id = department.id

        button.clicked.connect(self.button_clicked)

        button.setStyleSheet('''
        QPushButton {
        background-color: rgb(228, 244, 204);
        }
        ''')

        if self.is_first_button:
            button.click()
            self.is_first_button = False

        proxy = QGraphicsProxyWidget()
        proxy.setWidget(button)
        proxy.setPos(x, y)
        self.scene.addItem(proxy)

        self.nodes[department.id] = proxy

        if parent_item:
            parent_center = parent_item.sceneBoundingRect().center()
            current_center = proxy.sceneBoundingRect().center()
            line = self.scene.addLine(parent_center.x(), parent_center.y(), current_center.x(), current_center.y(),
                                      QPen(Qt.GlobalColor.black))

        child_departments = [d for d in self.departments if d.parent_id == department.id]
        child_x = x - len(child_departments) * 100 // 2
        for index, child in enumerate(child_departments):
            offset_y = (index % 2) * 50
            but_width = self.add_department_node(child, child_x, y + 50, proxy, level + 1)
            child_x += 250

        return button.width()