"""El Torito boot image configuration dialog."""

# This file is part of ISO Scalpel.
# Copyright (C) 2025 Jeremy Anderson <info@dcos.net>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, see <https://www.gnu.org/licenses/>
# or write to the Free Software Foundation, Inc., 51 Franklin Street,
# Fifth Floor, Boston, MA  02110-1301 USA.

from __future__ import annotations

from PySide6.QtWidgets import (
    QCheckBox,
    QComboBox,
    QDialog,
    QDialogButtonBox,
    QFileDialog,
    QFormLayout,
    QGroupBox,
    QHBoxLayout,
    QLabel,
    QLineEdit,
    QMessageBox,
    QPushButton,
    QSpinBox,
    QVBoxLayout,
    QWidget,
)

from ..iso_handler import BootInfo, IsoHandler


class BootDialog(QDialog):
    """Configure or clear an El Torito boot record."""

    def __init__(self, handler: IsoHandler, parent=None):
        super().__init__(parent)
        self.setWindowTitle("Boot Image (El Torito)")
        self.setMinimumWidth(480)
        self._handler = handler
        info = handler.get_boot_info()

        grp = QGroupBox("Boot Configuration")
        f = QFormLayout(grp)

        self.bootable = QCheckBox("Bootable")
        self.bootable.setChecked(info.bootable)
        f.addRow(self.bootable)

        self.boot_file = QLineEdit(info.boot_image_path)
        self.boot_file.setPlaceholderText("Path inside ISO, e.g. /BOOT.IMG;1")
        browse = QPushButton("Browse host file…")
        browse.clicked.connect(self._browse)
        row = QHBoxLayout()
        row.addWidget(self.boot_file, 1)
        row.addWidget(browse)
        w = QWidget()
        w.setLayout(row)
        f.addRow("Boot image:", w)
        self._local_file: str | None = None

        self.platform = QComboBox()
        self.platform.addItems(["0 — x86 (BIOS)", "1 — PowerPC", "2 — Mac", "0xEF — EFI"])
        f.addRow("Platform ID:", self.platform)
        if info.efi:
            self.platform.setCurrentIndex(3)

        self.media = QComboBox()
        # pycdlib accepts: 'noemul', 'floppy', 'hdemul'.  Floppy geometry is
        # conveyed via boot_load_size, so we offer the common sizes as a hint.
        self._media_items = [
            ("noemul (no emulation)", "noemul"),
            ("floppy 1.2 MiB", "floppy"),
            ("floppy 1.44 MiB", "floppy"),
            ("floppy 2.88 MiB", "floppy"),
            ("hdemul (hard disk)", "hdemul"),
        ]
        for label, _val in self._media_items:
            self.media.addItem(label)
        cur = {"noemul": 0, "floppy": 1, "hdemul": 4}.get(info.media_name, 0)
        self.media.setCurrentIndex(cur)
        f.addRow("Media:", self.media)

        self.load_seg = QSpinBox()
        self.load_seg.setRange(0, 0xFFFF)
        self.load_seg.setValue(info.load_segment or 0x07C0)
        self.load_seg.setDisplayIntegerBase(16)
        self.load_seg.setPrefix("0x")
        f.addRow("Load segment:", self.load_seg)

        self.load_size = QSpinBox()
        self.load_size.setRange(0, 100000)
        self.load_size.setSpecialValueText("auto (whole file)")
        self.load_size.setValue(info.load_size or 0)
        f.addRow("Load size (sectors):", self.load_size)

        self.info_table = QCheckBox("Patch boot-info-table (common for ISOLINUX)")
        self.info_table.setChecked(info.boot_info_table)
        f.addRow(self.info_table)

        # clear button
        self.clear_btn = QPushButton("Remove boot record")
        self.clear_btn.clicked.connect(self._clear)

        buttons = QDialogButtonBox(QDialogButtonBox.Ok | QDialogButtonBox.Cancel)
        buttons.accepted.connect(self._apply)
        buttons.rejected.connect(self.reject)

        layout = QVBoxLayout(self)
        layout.addWidget(grp)
        layout.addWidget(QLabel("Tip: the boot image file is added to the ISO automatically "
                                "when you select a host file."))
        layout.addStretch(1)
        bl = QHBoxLayout()
        bl.addWidget(self.clear_btn)
        bl.addStretch(1)
        bl.addWidget(buttons)
        layout.addLayout(bl)

    # ------------------------------------------------------------------ handlers
    def _browse(self) -> None:
        path, _ = QFileDialog.getOpenFileName(self, "Select boot image")
        if path:
            self._local_file = path
            self.boot_file.setText(path)

    def _clear(self) -> None:
        self._handler.clear_boot()
        QMessageBox.information(self, "Boot", "Boot record removed. Save the image to persist.")
        self.accept()

    def _apply(self) -> None:
        info = self._collect()
        try:
            self._handler.set_boot(info, boot_file_local=self._local_file)
        except Exception as exc:  # noqa: BLE001 -- user-facing error boundary
            QMessageBox.critical(self, "Boot", f"Failed to set boot record:\n{exc}")
            return
        self.accept()

    def _collect(self) -> BootInfo:
        info = BootInfo()
        info.bootable = self.bootable.isChecked()
        info.boot_image_path = self.boot_file.text().strip()
        info.platform_id = int(self.platform.currentText().split(" ", 1)[0], 0)
        info.media_name = self._media_items[self.media.currentIndex()][1]
        info.load_segment = self.load_seg.value()
        info.load_size = self.load_size.value() or None
        info.boot_info_table = self.info_table.isChecked()
        info.efi = info.platform_id == 0xEF
        info.boot_catalog_path = "BOOT.CAT;1"
        return info