Source code for radioviz.views.image_metadata_window

#  Copyright 2026 European Union
#  Author: Bulgheroni Antonio (antonio.bulgheroni@ec.europa.eu)
#  SPDX-License-Identifier: EUPL-1.2
"""
View for displaying image metadata in a read-only window.

This module provides a simple sub-window that presents metadata as
label/value pairs in a table, allowing users to inspect tags without
editing them.
"""

from __future__ import annotations

from typing import TYPE_CHECKING, Optional

from PySide6.QtCore import Qt
from PySide6.QtWidgets import (
    QAbstractItemView,
    QApplication,
    QHBoxLayout,
    QHeaderView,
    QLineEdit,
    QPushButton,
    QTableWidget,
    QTableWidgetItem,
    QVBoxLayout,
    QWidget,
)

from radioviz.views.sub_window import SubWindow

if TYPE_CHECKING:
    from radioviz.controllers.image_metadata_window_controller import ImageMetadataWindowController




class ImageMetadataWindow(SubWindow['ImageMetadataWindowController']):
    """
    Sub-window that displays image metadata entries.

    The view shows metadata in a two-column, read-only table with tag labels
    and their corresponding values.
    """

    def __init__(self, controller: 'ImageMetadataWindowController', parent: Optional[QWidget] = None) -> None:
        """
        Initialize the metadata window view.

        :param controller: Controller providing metadata entries.
        :type controller: radioviz.controllers.image_metadata_window_controller.ImageMetadataWindowController
        :param parent: Optional parent widget.
        :type parent: Optional[QWidget]
        """
        super().__init__(controller=controller, parent=parent)

        container = QWidget(self)
        layout = QVBoxLayout(container)
        layout.setContentsMargins(6, 6, 6, 6)

        controls_layout = QHBoxLayout()
        self.filter_input = QLineEdit(container)
        self.filter_input.setPlaceholderText('Filter tags...')
        self.copy_value_button = QPushButton('Copy value', container)
        self.copy_value_button.clicked.connect(self._copy_selected_value)
        controls_layout.addWidget(self.filter_input)
        controls_layout.addWidget(self.copy_value_button)

        self.table = QTableWidget(container)
        self.table.setColumnCount(3)
        self.table.setHorizontalHeaderLabels(['Tag', 'Name', 'Value'])
        self.table.setEditTriggers(QAbstractItemView.EditTrigger.NoEditTriggers)
        self.table.setSelectionBehavior(QAbstractItemView.SelectionBehavior.SelectRows)
        self.table.setSelectionMode(QAbstractItemView.SelectionMode.SingleSelection)
        self.table.verticalHeader().setVisible(False)
        self.table.horizontalHeader().setSectionResizeMode(0, QHeaderView.ResizeMode.ResizeToContents)
        self.table.horizontalHeader().setSectionResizeMode(1, QHeaderView.ResizeMode.ResizeToContents)
        self.table.horizontalHeader().setSectionResizeMode(2, QHeaderView.ResizeMode.Stretch)
        self.table.setAlternatingRowColors(True)

        self._populate_table()
        self.filter_input.textChanged.connect(self._apply_filter)

        layout.addLayout(controls_layout)
        layout.addWidget(self.table)
        self.setWidget(container)
        self.setWindowTitle(self.controller.name)
        self.resize(460, 320)



    def _populate_table(self) -> None:
        """
        Populate the table with metadata entries from the controller.

        :return: None
        :rtype: None
        """
        entries = self.controller.metadata_items()
        if not entries:
            entries = [('', 'No metadata available', '')]

        self.table.setRowCount(len(entries))
        for row, (tag, name, value) in enumerate(entries):
            tag_item = QTableWidgetItem(tag)
            name_item = QTableWidgetItem(name)
            value_item = QTableWidgetItem(value)
            tag_item.setFlags(tag_item.flags() & ~Qt.ItemFlag.ItemIsEditable)
            name_item.setFlags(name_item.flags() & ~Qt.ItemFlag.ItemIsEditable)
            value_item.setFlags(value_item.flags() & ~Qt.ItemFlag.ItemIsEditable)
            if value:
                value_item.setToolTip(value)
            self.table.setItem(row, 0, tag_item)
            self.table.setItem(row, 1, name_item)
            self.table.setItem(row, 2, value_item)

        self._apply_filter(self.filter_input.text())




    def _apply_filter(self, text: str) -> None:
        """
        Filter table rows based on the provided text.

        :param text: Filter text to apply.
        :type text: str
        :return: None
        :rtype: None
        """
        needle = text.strip().lower()
        for row in range(self.table.rowCount()):
            if not needle:
                self.table.setRowHidden(row, False)
                continue
            tag_item = self.table.item(row, 0)
            name_item = self.table.item(row, 1)
            value_item = self.table.item(row, 2)
            haystack = ' '.join(
                [
                    tag_item.text() if tag_item else '',
                    name_item.text() if name_item else '',
                    value_item.text() if value_item else '',
                ]
            ).lower()
            self.table.setRowHidden(row, needle not in haystack)




    def _copy_selected_value(self) -> None:
        """
        Copy the selected row's value to the clipboard.

        :return: None
        :rtype: None
        """
        row = self.table.currentRow()
        if row < 0:
            return
        item = self.table.item(row, 2)
        if item is None:
            return
        QApplication.clipboard().setText(item.text())