pyssh-client/app/ui/tabs.py

"""Widgets d'onglet : terminal SSH, terminal local, SFTP autonome.

Chaque onglet encapsule une connexion (SSH ou locale) qui expose la meme
interface de signaux (connected / data_received / disconnected / error / send /
resize), ce qui permet a `BaseTerminalTab` de rester independante du type de
connexion sous-jacent.
"""
from __future__ import annotations

import re
from datetime import datetime
from pathlib import Path

from PySide6.QtCore import Qt, Signal, QTimer
from PySide6.QtGui import QKeySequence, QShortcut
from PySide6.QtWidgets import (
    QWidget, QVBoxLayout, QHBoxLayout, QToolButton, QLabel, QMessageBox, QSplitter,
    QFrame, QLineEdit, QFileDialog,
)

from app.session_manager import Session, AUTH_KEY, AUTH_PASSWORD
from app.ssh_connection import SSHConnection
from app.local_terminal import LocalTerminalConnection, SHELL_POWERSHELL, SHELL_LABELS
from app.terminal_widget import TerminalWidget
from app.sftp_panel import SFTPPanel
from app.dialogs.tunnel_dialog import TunnelDialog
from app.tunnels import TunnelManager
from app.dialogs.connect_prompt import ask_secret, confirm_host_key, confirm_host_key_change
from app.services.ssh_target import detect_ssh_target
from app.services.reconnect import compute_backoff_delay

# sequences d'echappement ANSI, retirees des journaux pour qu'ils restent lisibles
ANSI_ESCAPE_RE = re.compile(
    r"\x1b\[[0-9;?]*[a-zA-Z]"                    # CSI : couleurs, deplacements du curseur
    r"|\x1b\][^\x07\x1b]*(?:\x07|\x1b\\)"       # OSC : titre de fenetre
    r"|\x1b[()][A-Z0-9]"                         # jeux de caracteres
    r"|\x1b[=>]"                                 # mode clavier
    r"|[\x00-\x08\x0b\x0c\x0e-\x1f]"            # autres caracteres de controle
)


class BaseTerminalTab(QWidget):
    """Base commune a un onglet terminal : barre de statut + terminal, autour d'une
    connexion (SSH ou locale) qui expose la meme interface de signaux
    (connected / data_received / disconnected / error / send / resize)."""

    def __init__(self, initial_status: str, parent=None):
        super().__init__(parent)
        layout = QVBoxLayout(self)
        layout.setContentsMargins(0, 0, 0, 0)
        layout.setSpacing(0)

        self.bar = QHBoxLayout()
        self.bar.setContentsMargins(10, 6, 10, 6)
        self.status_label = QLabel(initial_status)
        self.status_label.setObjectName("statusLabel")
        self.bar.addWidget(self.status_label, 1)

        # Apparait quand la connexion tombe : les serveurs de test redemarrent souvent,
        # inutile de fermer l'onglet et de tout ressaisir.
        self.reconnect_btn = QToolButton()
        self.reconnect_btn.setObjectName("primary")
        self.reconnect_btn.setText("⟳ Reconnecter")
        self.reconnect_btn.hide()
        self.reconnect_btn.clicked.connect(self.reconnect)
        self.bar.addWidget(self.reconnect_btn)

        self.log_btn = QToolButton()
        self.log_btn.setText("⏺ Journal")
        self.log_btn.setToolTip("Enregistrer la session dans un fichier")
        self.log_btn.setCheckable(True)
        self.log_btn.clicked.connect(self.toggle_logging)
        self.bar.addWidget(self.log_btn)
        bar_frame = QFrame()
        bar_frame.setObjectName("tabBar")
        bar_frame.setLayout(self.bar)
        layout.addWidget(bar_frame)

        self.splitter = QSplitter(Qt.Horizontal)
        self.terminal = TerminalWidget()
        self.splitter.addWidget(self.terminal)
        layout.addWidget(self.splitter, 1)

        # barre de recherche, masquee tant qu'on n'a pas fait Ctrl+F
        self.search_bar = QFrame()
        self.search_bar.setObjectName("tabBar")
        search_layout = QHBoxLayout(self.search_bar)
        search_layout.setContentsMargins(10, 4, 10, 4)
        self.search_input = QLineEdit()
        self.search_input.setPlaceholderText("Rechercher dans l'historique... (Entree = precedent, Echap = fermer)")
        self.search_status = QLabel("")
        self.search_status.setObjectName("statusLabel")
        close_search = QToolButton()
        close_search.setText("✕")
        search_layout.addWidget(self.search_input, 1)
        search_layout.addWidget(self.search_status)
        search_layout.addWidget(close_search)
        self.search_bar.hide()
        layout.addWidget(self.search_bar)

        self.terminal.search_requested.connect(self.open_search)
        self.search_input.returnPressed.connect(self._run_search)
        close_search.clicked.connect(self.close_search)
        QShortcut(QKeySequence(Qt.Key_Escape), self.search_input, activated=self.close_search)

        self.connection = None  # assigne par les sous-classes
        self._log_file = None
        self._connection_generation = 0
        self._closing = False

    # ---------- journalisation ----------
    def toggle_logging(self) -> None:
        if self._log_file:
            self.stop_logging()
            return
        default = Path.home() / f"session-{datetime.now():%Y%m%d-%H%M%S}.log"
        path, _ = QFileDialog.getSaveFileName(self, "Journaliser la session", str(default), "Journal (*.log)")
        if not path:
            self.log_btn.setChecked(False)
            return
        try:
            self._log_file = open(path, "a", encoding="utf-8", errors="replace")
        except OSError as exc:
            QMessageBox.critical(self, "Erreur", f"Impossible d'ecrire le journal : {exc}")
            self.log_btn.setChecked(False)
            return
        self._log_file.write(f"\n===== Session du {datetime.now():%d/%m/%Y %H:%M:%S} =====\n")
        self.log_btn.setChecked(True)
        self.log_btn.setToolTip(f"Journalisation active : {path}")

    def stop_logging(self) -> None:
        if self._log_file:
            try:
                self._log_file.close()
            except OSError:
                pass
            self._log_file = None
        self.log_btn.setChecked(False)
        self.log_btn.setToolTip("Enregistrer la session dans un fichier")

    def _log_output(self, data: bytes) -> None:
        if not self._log_file:
            return
        # on retire les sequences d'echappement : un journal doit rester lisible
        text = ANSI_ESCAPE_RE.sub("", data.decode("utf-8", errors="replace"))
        try:
            self._log_file.write(text)
            self._log_file.flush()
        except OSError:
            self.stop_logging()

    def _wire_connection(self) -> None:
        # Un signal deconnexion/erreur/connexion emis par une connexion remplacee
        # entre-temps (ex. reconnexion en cours) ne doit pas ecraser l'etat de la
        # nouvelle : chaque connexion est associee a la generation en cours au
        # moment ou elle est cablee, et un signal d'une generation perimee est ignore.
        generation = self._connection_generation
        self.connection.connected.connect(lambda: self._on_current_generation(generation, self._on_connected))
        self.connection.data_received.connect(self.terminal.feed)
        self.connection.data_received.connect(self._log_output)
        self.connection.disconnected.connect(
            lambda reason: self._on_current_generation(generation, self._on_disconnected, reason)
        )
        self.connection.error.connect(
            lambda message: self._on_current_generation(generation, self._on_error, message)
        )
        self.terminal.data_to_send.connect(self.connection.send)
        self.terminal.resized.connect(self.connection.resize)

    def _on_current_generation(self, generation: int, fn, *args) -> None:
        if generation == self._connection_generation:
            fn(*args)

    def _create_connection(self):
        """Fabrique la connexion. Redefinie par chaque sous-classe : c'est ce qui
        permet de la recreer a l'identique lors d'une reconnexion."""
        raise NotImplementedError

    def start_connection(self) -> None:
        self._connection_generation += 1
        self.connection = self._create_connection()
        self._wire_connection()
        self.connection.start()

    def reconnect(self) -> None:
        if self.connection:
            self.connection.close_connection()
            self.connection.wait(1500)
        self.terminal.reset_screen()
        self.reconnect_btn.hide()
        self.status_label.setText("○ Reconnexion...")
        self.start_connection()

    def _on_connected(self) -> None:
        self.reconnect_btn.hide()
        self.terminal.setFocus()

    def _on_disconnected(self, reason: str) -> None:
        self.status_label.setText(f"● Deconnecte ({reason})")
        self.reconnect_btn.show()

    def _on_error(self, message: str) -> None:
        self.status_label.setText(f"● Erreur : {message}")
        self.reconnect_btn.show()
        QMessageBox.critical(self, "Erreur", message)

    # ---------- recherche dans l'historique ----------
    def open_search(self) -> None:
        self.search_bar.show()
        self.search_input.setFocus()
        self.search_input.selectAll()

    def close_search(self) -> None:
        self.search_bar.hide()
        self.search_status.clear()
        self.terminal.setFocus()

    def _run_search(self) -> None:
        needle = self.search_input.text()
        if not needle:
            return
        found = self.terminal.find_text(needle)
        self.search_status.setText("" if found else "aucun resultat")

    def close_connection(self) -> None:
        self._closing = True  # ne jamais reconnecter automatiquement une fermeture voulue
        self.stop_logging()
        if self.connection:
            self.connection.close_connection()
            self.connection.wait(2000)


class SessionTabWidget(BaseTerminalTab):
    """Un onglet = une connexion SSH avec son terminal et un panneau SFTP optionnel."""

    def __init__(
        self, session: Session, secret: str, bastion_target=None, bastion_password: str = "",
        parent=None,
    ):
        super().__init__(f"○ Connexion a {session.username}@{session.host}...", parent)
        self.session = session
        self._bastion_target = bastion_target
        self._bastion_password = bastion_password
        self.sftp_panel: SFTPPanel | None = None

        self.sftp_toggle = QToolButton()
        self.sftp_toggle.setText("📁 Fichiers (SFTP)")
        self.sftp_toggle.setToolTip("Afficher / masquer le navigateur de fichiers SFTP")
        self.sftp_toggle.setCheckable(True)
        self.sftp_toggle.setChecked(True)
        self.sftp_toggle.setEnabled(False)
        self.bar.addWidget(self.sftp_toggle)

        self.tunnel_btn = QToolButton()
        self.tunnel_btn.setText("🔀 Tunnels")
        self.tunnel_btn.setToolTip("Redirections de ports SSH (-L / -R)")
        self.tunnel_btn.setEnabled(False)
        self.tunnel_btn.clicked.connect(self.open_tunnels)
        self.bar.addWidget(self.tunnel_btn)

        self.tunnel_manager: TunnelManager | None = None

        self._secret = secret
        self.sftp_toggle.toggled.connect(self._toggle_sftp)

        # Reconnexion automatique : un timer a declenchement unique pour la
        # reconnexion elle-meme, et un second pour rafraichir le compte a
        # rebours affiche a l'utilisateur pendant l'attente.
        self._reconnect_attempt = 0
        self._reconnect_seconds_left = 0
        self._reconnect_last_reason = ""
        self._reconnect_timer = QTimer(self)
        self._reconnect_timer.setSingleShot(True)
        self._reconnect_timer.timeout.connect(self._do_reconnect)
        self._reconnect_countdown_timer = QTimer(self)
        self._reconnect_countdown_timer.timeout.connect(self._tick_reconnect_countdown)

        self.start_connection()

    def _create_connection(self):
        session = self.session
        connection = SSHConnection(
            host=session.host,
            port=session.port,
            username=session.username,
            auth_type=session.auth_type,
            key_path=session.key_path,
            password=self._secret if session.auth_type == AUTH_PASSWORD else "",
            passphrase=self._secret if session.auth_type == AUTH_KEY else "",
            # comme MobaXterm : le navigateur de fichiers est la des l'ouverture,
            # pas cache derriere une action supplementaire
            open_sftp_on_connect=True,
            bastion_target=self._bastion_target,
            bastion_password=self._bastion_password,
            keepalive_enabled=session.keepalive_enabled,
            keepalive_interval=session.keepalive_interval,
            keepalive_count_max=session.keepalive_count_max,
        )
        connection.sftp_ready.connect(self._on_sftp_ready)
        connection.password_prompt.connect(self._on_password_prompt)
        connection.host_key_prompt.connect(self._on_host_key_prompt)
        connection.host_key_changed_prompt.connect(self._on_host_key_changed_prompt)
        connection.passphrase_prompt.connect(self._on_passphrase_prompt)
        return connection

    def open_tunnels(self) -> None:
        if not self.tunnel_manager:
            QMessageBox.information(self, "Tunnels", "La session doit etre connectee.")
            return
        TunnelDialog(self.tunnel_manager, parent=self).exec()
        actifs = len(self.tunnel_manager.tunnels)
        self.tunnel_btn.setText(f"🔀 Tunnels ({actifs})" if actifs else "🔀 Tunnels")

    def _on_connected(self) -> None:
        self._reconnect_attempt = 0  # une connexion reussie remet le compteur a zero
        self.status_label.setText(f"● Connecte : {self.session.username}@{self.session.host}:{self.session.port}")
        transport = self.connection.client.get_transport() if self.connection.client else None
        if transport:
            self.tunnel_manager = TunnelManager(transport)
            self.tunnel_btn.setEnabled(True)
        # le bouton n'est active qu'une fois le canal SFTP reellement ouvert
        # (_on_sftp_ready) : certains serveurs n'exposent pas le sous-systeme SFTP
        super()._on_connected()

    def _on_disconnected(self, reason: str) -> None:
        super()._on_disconnected(reason)
        self.sftp_toggle.setEnabled(False)
        self._maybe_schedule_reconnect(reason)

    def reconnect(self) -> None:
        self._cancel_reconnect_timers()
        super().reconnect()

    # ---------- reconnexion automatique ----------
    def _cancel_reconnect_timers(self) -> None:
        self._reconnect_timer.stop()
        self._reconnect_countdown_timer.stop()

    def _maybe_schedule_reconnect(self, reason: str) -> None:
        if self._closing or not self.session.reconnect_enabled:
            return
        max_attempts = self.session.reconnect_max_attempts
        self._reconnect_attempt += 1
        if max_attempts and self._reconnect_attempt > max_attempts:
            self.status_label.setText(
                f"● Deconnecte ({reason}). Abandon apres {max_attempts} tentative(s) de reconnexion."
            )
            self.reconnect_btn.show()
            return
        self._reconnect_last_reason = reason
        self._reconnect_seconds_left = compute_backoff_delay(
            self._reconnect_attempt, self.session.reconnect_initial_delay,
        )
        self._update_reconnect_status()
        self._reconnect_countdown_timer.start(1000)
        self._reconnect_timer.start(self._reconnect_seconds_left * 1000)

    def _tick_reconnect_countdown(self) -> None:
        self._reconnect_seconds_left -= 1
        if self._reconnect_seconds_left <= 0:
            self._reconnect_countdown_timer.stop()
            return
        self._update_reconnect_status()

    def _update_reconnect_status(self) -> None:
        max_attempts = self.session.reconnect_max_attempts
        total = f"/{max_attempts}" if max_attempts else ""
        self.status_label.setText(
            f"● Connexion perdue ({self._reconnect_last_reason}). "
            f"Reconnexion dans {self._reconnect_seconds_left} seconde(s)... "
            f"(Tentative {self._reconnect_attempt}{total})"
        )

    def _do_reconnect(self) -> None:
        self._reconnect_countdown_timer.stop()
        if self._closing:
            return
        self.reconnect()

    def _on_host_key_prompt(self, hostname: str, key_type: str, fingerprint: str) -> None:
        accepted = confirm_host_key(self, hostname, key_type, fingerprint)
        self.connection.confirm_host_key(accepted)

    def _on_host_key_changed_prompt(self, hostname: str, key_type: str, old_fp: str, new_fp: str) -> None:
        accepted = confirm_host_key_change(self, hostname, key_type, old_fp, new_fp)
        self.connection.confirm_host_key_change(accepted)

    def _on_passphrase_prompt(self, key_path: str) -> None:
        text, ok = ask_secret(self, "Passphrase requise", f"Passphrase pour la cle :\n{key_path}")
        self.connection.provide_passphrase(text if ok else None)

    def _on_password_prompt(self, target: str) -> None:
        text, ok = ask_secret(self, "Mot de passe", f"Mot de passe pour {target} :")
        self.connection.provide_password(text if ok else None)

    def _on_sftp_ready(self, sftp) -> None:
        """Le canal SFTP a ete ouvert en arriere-plan : on affiche le navigateur de
        fichiers a cote du terminal, sans action de l'utilisateur."""
        if self.sftp_panel is not None:
            return
        self.sftp_panel = SFTPPanel(sftp, transfer_sftp_factory=self._open_transfer_channel)
        self.splitter.insertWidget(0, self.sftp_panel)
        self.splitter.setSizes([460, 540])
        self.sftp_toggle.setEnabled(True)
        self.sftp_toggle.setChecked(True)
        self.terminal.setFocus()

    def _open_transfer_channel(self):
        """Ouvre un second canal SFTP, dedie aux transferts, pour ne jamais faire
        attendre la navigation derriere un gros envoi/reception (voir SFTPPanel)."""
        import paramiko
        return paramiko.SFTPClient.from_transport(self.connection.client.get_transport())

    def close_connection(self) -> None:
        self._cancel_reconnect_timers()
        if self.sftp_panel:
            self.sftp_panel.shutdown()
        if self.tunnel_manager:
            self.tunnel_manager.stop_all()
            self.tunnel_manager = None
        super().close_connection()

    def _toggle_sftp(self, checked: bool) -> None:
        if self.sftp_panel is not None:
            self.sftp_panel.setVisible(checked)


class SFTPTabWidget(QWidget):
    """Onglet SFTP autonome (facon WinSCP) : double panneau de fichiers, sans terminal."""

    def __init__(
        self, session: Session, secret: str, bastion_target=None, bastion_password: str = "",
        parent=None,
    ):
        super().__init__(parent)
        self.session = session
        self.sftp_panel: SFTPPanel | None = None

        layout = QVBoxLayout(self)
        layout.setContentsMargins(0, 0, 0, 0)
        layout.setSpacing(0)

        bar = QHBoxLayout()
        bar.setContentsMargins(10, 6, 10, 6)
        self.status_label = QLabel(f"○ Connexion SFTP a {session.username}@{session.host}...")
        self.status_label.setObjectName("statusLabel")
        bar.addWidget(self.status_label, 1)
        bar_frame = QFrame()
        bar_frame.setObjectName("tabBar")
        bar_frame.setLayout(bar)
        layout.addWidget(bar_frame)

        self.container = QVBoxLayout()
        holder = QWidget()
        holder.setLayout(self.container)
        layout.addWidget(holder, 1)

        self.connection = SSHConnection(
            host=session.host,
            port=session.port,
            username=session.username,
            auth_type=session.auth_type,
            key_path=session.key_path,
            password=secret if session.auth_type == AUTH_PASSWORD else "",
            passphrase=secret if session.auth_type == AUTH_KEY else "",
            open_shell=False,
            open_sftp_on_connect=True,
            bastion_target=bastion_target,
            bastion_password=bastion_password,
            keepalive_enabled=session.keepalive_enabled,
            keepalive_interval=session.keepalive_interval,
            keepalive_count_max=session.keepalive_count_max,
        )
        self.connection.sftp_ready.connect(self._on_sftp_ready)
        self.connection.password_prompt.connect(self._on_password_prompt)
        self.connection.error.connect(self._on_error)
        self.connection.disconnected.connect(self._on_disconnected)
        self.connection.host_key_prompt.connect(self._on_host_key_prompt)
        self.connection.host_key_changed_prompt.connect(self._on_host_key_changed_prompt)
        self.connection.passphrase_prompt.connect(self._on_passphrase_prompt)
        self.connection.start()

    def _on_sftp_ready(self, sftp) -> None:
        self.sftp_panel = SFTPPanel(sftp, transfer_sftp_factory=self._open_transfer_channel)
        self.container.addWidget(self.sftp_panel)
        self.status_label.setText(
            f"● SFTP connecte : {self.session.username}@{self.session.host}:{self.session.port}"
        )

    def _open_transfer_channel(self):
        import paramiko
        return paramiko.SFTPClient.from_transport(self.connection.client.get_transport())

    def _on_disconnected(self, reason: str) -> None:
        self.status_label.setText(f"● Deconnecte ({reason})")

    def _on_error(self, message: str) -> None:
        self.status_label.setText(f"● Erreur : {message}")
        QMessageBox.critical(self, "Erreur SFTP", message)

    def _on_host_key_prompt(self, hostname: str, key_type: str, fingerprint: str) -> None:
        self.connection.confirm_host_key(confirm_host_key(self, hostname, key_type, fingerprint))

    def _on_host_key_changed_prompt(self, hostname: str, key_type: str, old_fp: str, new_fp: str) -> None:
        self.connection.confirm_host_key_change(
            confirm_host_key_change(self, hostname, key_type, old_fp, new_fp)
        )

    def _on_passphrase_prompt(self, key_path: str) -> None:
        text, ok = ask_secret(self, "Passphrase requise", f"Passphrase pour la cle :\n{key_path}")
        self.connection.provide_passphrase(text if ok else None)

    def _on_password_prompt(self, target: str) -> None:
        text, ok = ask_secret(self, "Mot de passe", f"Mot de passe pour {target} :")
        self.connection.provide_password(text if ok else None)

    def close_connection(self) -> None:
        if self.sftp_panel:
            self.sftp_panel.shutdown()
        self.connection.close_connection()
        self.connection.wait(2000)


class LocalTerminalTabWidget(BaseTerminalTab):
    """Un onglet = un terminal Windows local (PowerShell / cmd), sans session enregistree."""

    sftp_requested = Signal(object)  # cible ssh detectee (ou None)

    def __init__(self, shell: str = SHELL_POWERSHELL, parent=None):
        super().__init__(f"○ Ouverture de {SHELL_LABELS.get(shell, shell)}...", parent)
        self.shell = shell

        # Meme dans un terminal local, on tape souvent "ssh user@ip" a la main :
        # ce bouton ouvre le SFTP sur cet hote, sans passer par un favori.
        self.sftp_btn = QToolButton()
        self.sftp_btn.setText("📁 SFTP sur cette connexion")
        self.sftp_btn.setToolTip(
            "Ouvre un gestionnaire de fichiers SFTP sur l'hote de la commande ssh tapee ici"
        )
        self.sftp_btn.clicked.connect(
            lambda: self.sftp_requested.emit(detect_ssh_target(self.terminal.buffer_text()))
        )
        self.bar.addWidget(self.sftp_btn)

        self.start_connection()

    def _create_connection(self):
        return LocalTerminalConnection(shell=self.shell)

    def _on_connected(self) -> None:
        self.status_label.setText(f"● Terminal local — {SHELL_LABELS.get(self.shell, self.shell)}")
        super()._on_connected()