"""Fenêtre d'historique des sessions WGSecure."""
from PyQt6.QtWidgets import (
    QDialog, QVBoxLayout, QHBoxLayout, QTableWidget,
    QTableWidgetItem, QPushButton, QLabel, QHeaderView,
    QMessageBox, QWidget,
)
from PyQt6.QtCore import Qt
from PyQt6.QtGui import QColor, QFont

from app.core import history as hist
from app.ui import theme

def _css() -> str:
    """Feuille de style de la fenêtre d'historique.

    Fonction et non constante : bâtie à l'import, elle retenait les couleurs
    du thème chargé à ce moment-là et ignorait celui appliqué au démarrage.
    """
    return f"""
    QDialog   {{ background: {theme.BG_SUNKEN}; }}
    QLabel    {{ color: {theme.TEXT}; background: transparent; }}
    QTableWidget {{
        background: {theme.BG}; color: {theme.TEXT}; gridline-color: {theme.BG_RAISED};
        border: none; font-size: 11px;
    }}
    QHeaderView::section {{
        background: {theme.BG_RAISED}; color: {theme.TEXT}; padding: 5px;
        border: none; font-weight: bold; font-size: 11px;
    }}
    QTableWidget::item:selected {{ background: {theme.ACCENT};
                                   color: {theme.ON_SOLID}; }}
    QPushButton {{
        background: {theme.BG_RAISED}; color: {theme.TEXT}; border-radius: 5px;
        padding: 6px 14px; border: none;
    }}
    QPushButton:hover {{ background: {theme.ACCENT_HOVER};
                         color: {theme.ON_SOLID}; }}
"""


class HistoryDialog(QDialog):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.setWindowTitle("WGSecure — Historique des sessions")
        self.setMinimumSize(680, 420)
        self.setStyleSheet(_css())
        self._build_ui()
        self._load()

    def _build_ui(self):
        layout = QVBoxLayout(self)
        layout.setContentsMargins(0, 0, 0, 0)
        layout.setSpacing(0)

        # Bannière
        banner = QLabel("  📊  Historique des sessions VPN")
        banner.setFixedHeight(40)
        banner.setStyleSheet(
            f"background: {theme.BG_SUNKEN}; color: {theme.TEXT}; font-size: 14px; font-weight: bold;"
        )
        layout.addWidget(banner)

        # Tableau
        self._table = QTableWidget(0, 6)
        self._table.setHorizontalHeaderLabels([
            "Date début", "Serveur", "Profil", "Durée", "↓ Reçu", "↑ Envoyé"
        ])
        self._table.horizontalHeader().setSectionResizeMode(1, QHeaderView.ResizeMode.Stretch)
        self._table.horizontalHeader().setSectionResizeMode(0, QHeaderView.ResizeMode.ResizeToContents)
        self._table.verticalHeader().setVisible(False)
        self._table.setSelectionBehavior(QTableWidget.SelectionBehavior.SelectRows)
        self._table.setEditTriggers(QTableWidget.EditTrigger.NoEditTriggers)
        self._table.setAlternatingRowColors(True)
        self._table.setStyleSheet(
            _css() +
            f"QTableWidget {{ alternate-background-color: {theme.BG_RAISED}; }}"
        )
        layout.addWidget(self._table)

        # Barre infos + boutons
        bar = QLabel("")
        bar.setFixedHeight(1)
        bar.setStyleSheet(f"background: {theme.BG_RAISED};")
        layout.addWidget(bar)

        btn_row_w = QVBoxLayout()
        btn_row_w.setContentsMargins(0, 0, 0, 0)

        bottom = QHBoxLayout()
        bottom.setContentsMargins(14, 8, 14, 12)

        self._summary_lbl = QLabel("")
        self._summary_lbl.setStyleSheet(f"color: {theme.TEXT_FAINT}; font-size: 11px;")
        bottom.addWidget(self._summary_lbl)
        bottom.addStretch()

        btn_clear = QPushButton("🗑️  Effacer l'historique")
        btn_clear.setStyleSheet(
            f"QPushButton {{ background: {theme.FAIL_SOLID}; color: {theme.TEXT}; border-radius: 5px;"
            " padding: 6px 14px; border: none; }"
            "QPushButton:hover { background: #e74c3c; }"
        )
        btn_clear.clicked.connect(self._clear)
        btn_close = QPushButton("Fermer")
        btn_close.clicked.connect(self.accept)
        bottom.addWidget(btn_clear)
        bottom.addWidget(btn_close)

        bottom_w = QWidget()
        bottom_w.setStyleSheet(f"background: {theme.BG_SUNKEN};")
        bottom_w.setLayout(bottom)
        layout.addWidget(bottom_w)

    def _load(self):
        self._table.setRowCount(0)
        sessions = hist.get_sessions(100)
        total_rx = total_tx = total_s = 0

        for row, s in enumerate(sessions):
            self._table.insertRow(row)
            end = s.get("end")
            color = theme.OK_TEXT if end else theme.WARN_TEXT  # vert=terminée, jaune=en cours

            cells = [
                s.get("start", "—"),
                s.get("server", "—"),
                s.get("profile", "Défaut"),
                hist.fmt_duration(s.get("duration")),
                hist.fmt_bytes(s.get("rx", 0)),
                hist.fmt_bytes(s.get("tx", 0)),
            ]
            for col, text in enumerate(cells):
                item = QTableWidgetItem(text)
                item.setForeground(QColor(color))
                item.setTextAlignment(
                    Qt.AlignmentFlag.AlignVCenter |
                    (Qt.AlignmentFlag.AlignRight if col >= 3
                     else Qt.AlignmentFlag.AlignLeft)
                )
                self._table.setItem(row, col, item)

            total_rx += s.get("rx", 0)
            total_tx += s.get("tx", 0)
            if s.get("duration"):
                total_s += s["duration"]

        n = len(sessions)
        self._summary_lbl.setText(
            f"{n} session{'s' if n > 1 else ''}  •  "
            f"Total ↓ {hist.fmt_bytes(total_rx)}  "
            f"↑ {hist.fmt_bytes(total_tx)}  •  "
            f"Durée cumulée : {hist.fmt_duration(total_s)}"
        )

    def _clear(self):
        reply = QMessageBox.question(
            self, "Confirmer",
            "Effacer tout l'historique des sessions ?",
            QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
        )
        if reply == QMessageBox.StandardButton.Yes:
            hist.clear()
            self._load()