"""
ui/windows/missing_plugins_dialog.py

Shown when loading a profile that requires plugins that are either not
installed or installed but missing their dependencies.

Each row is one of two kinds:
  'plugin' — plugin not installed → Download (if source_url) + Install from file…
  'deps'   — plugin installed but deps absent → Reinstall from file…
"""

import os
import tempfile

from PyQt6.QtWidgets import (
    QDialog, QVBoxLayout, QHBoxLayout, QLabel,
    QPushButton, QFrame, QFileDialog, QMessageBox, QApplication,
)
from PyQt6.QtCore import Qt


class MissingPluginsDialog(QDialog):
    def __init__(self, missing_manifests: list, plugin_mgr, parent=None):
        super().__init__(parent, Qt.WindowType.Dialog)
        self._plugin_mgr    = plugin_mgr
        self._missing       = missing_manifests
        self._install_btns: dict  = {}   # plugin_id -> "Install from file…" button
        self._download_btns: dict = {}   # plugin_id -> "Download" button (optional)
        self._status_lbls: dict   = {}   # plugin_id -> status QLabel
        self.setWindowTitle("Missing Plugins")
        self.setMinimumWidth(540)
        self._build()

    # ── Build ─────────────────────────────────────────────────────────────

    def _build(self):
        root = QVBoxLayout(self)
        root.setSpacing(12)
        root.setContentsMargins(16, 16, 16, 16)

        intro = QLabel(
            "This profile requires plugins that are not ready on this machine.\n"
            "Fix the issues below, then click <b>Continue</b> to finish loading."
        )
        intro.setWordWrap(True)
        root.addWidget(intro)

        root.addWidget(_hline())

        for pm in self._missing:
            root.addLayout(self._plugin_row(pm))

        root.addWidget(_hline())

        btn_row = QHBoxLayout()
        btn_row.addStretch()

        cancel_btn = QPushButton("Cancel load")
        cancel_btn.clicked.connect(self.reject)
        btn_row.addWidget(cancel_btn)

        self._continue_btn = QPushButton("Continue")
        self._continue_btn.setObjectName("applyButton")
        self._continue_btn.clicked.connect(self.accept)
        btn_row.addWidget(self._continue_btn)

        root.addLayout(btn_row)
        self._refresh_continue_btn()

    def _plugin_row(self, pm: dict) -> QHBoxLayout:
        row = QHBoxLayout(); row.setSpacing(8)

        # Left: name + detail
        info_col = QVBoxLayout(); info_col.setSpacing(2)
        name_lbl = QLabel(f"<b>{pm.get('name', pm['plugin_id'])}</b>"
                          f"  <small>v{pm.get('version', '?')}</small>")
        info_col.addWidget(name_lbl)

        if pm.get("kind") == "deps":
            detail = "Missing packages: " + ", ".join(pm.get("missing_deps", []))
        elif pm.get("description"):
            detail = pm["description"]
        else:
            detail = ""
        if detail:
            dl = QLabel(detail)
            dl.setObjectName("traceSource"); dl.setWordWrap(True)
            info_col.addWidget(dl)
        row.addLayout(info_col, 1)

        # Status label
        is_deps = pm.get("kind") == "deps"
        status_lbl = QLabel("Deps missing" if is_deps else "Not installed")
        status_lbl.setObjectName("traceSource")
        status_lbl.setFixedWidth(130)
        status_lbl.setAlignment(Qt.AlignmentFlag.AlignRight | Qt.AlignmentFlag.AlignVCenter)
        self._status_lbls[pm["plugin_id"]] = status_lbl
        row.addWidget(status_lbl)

        # Download button — only for missing plugins with a source_url
        source_url = pm.get("source_url", "")
        if source_url and not is_deps:
            dl_btn = QPushButton("Download")
            dl_btn.setObjectName("configButton")
            dl_btn.setFixedWidth(90)
            dl_btn.setToolTip(f"Download from:\n{source_url}")
            dl_btn.clicked.connect(lambda _, p=pm: self._download(p))
            self._download_btns[pm["plugin_id"]] = dl_btn
            row.addWidget(dl_btn)

        # Install / Reinstall from file button
        btn_label = "Reinstall from file…" if is_deps else "Install from file…"
        inst_btn = QPushButton(btn_label)
        inst_btn.setObjectName("configButton")
        inst_btn.setFixedWidth(150)
        if is_deps:
            inst_btn.setToolTip("Reinstall with a zip that bundles deps in vendor/")
        inst_btn.clicked.connect(lambda _, p=pm: self._pick_file(p))
        self._install_btns[pm["plugin_id"]] = inst_btn
        row.addWidget(inst_btn)

        return row

    # ── Install paths ─────────────────────────────────────────────────────

    def _pick_file(self, pm: dict):
        path, _ = QFileDialog.getOpenFileName(
            self, f"Install {pm.get('name', pm['plugin_id'])}", "",
            "Plugin Archives (*.zip)"
        )
        if path:
            self._finish_install(pm, path, cleanup=False)

    def _download(self, pm: dict):
        import urllib.request

        url = pm.get("source_url", "")
        if not url:
            return

        pid = pm["plugin_id"]
        self._set_row_busy(pid, True, "Downloading…")

        tmp_path = None
        try:
            tmp_fd, tmp_path = tempfile.mkstemp(suffix=".zip")
            os.close(tmp_fd)

            status_lbl = self._status_lbls[pid]

            def _progress(block_count, block_size, total):
                if total > 0:
                    pct = min(100, block_count * block_size * 100 // total)
                    status_lbl.setText(f"Downloading… {pct}%")
                QApplication.processEvents()

            urllib.request.urlretrieve(url, tmp_path, reporthook=_progress)

        except Exception as exc:
            self._set_row_busy(pid, False, "Download failed")
            QMessageBox.critical(self, "Download Failed", str(exc))
            if tmp_path:
                _silent_remove(tmp_path)
            return

        self._status_lbls[pid].setText("Installing…")
        QApplication.processEvents()
        self._finish_install(pm, tmp_path, cleanup=True)

    def _finish_install(self, pm: dict, zip_path: str, cleanup: bool):
        pid = pm["plugin_id"]
        try:
            manifest = self._plugin_mgr.install_from_zip(zip_path)
        except Exception as exc:
            self._set_row_busy(pid, False,
                               "Deps missing" if pm.get("kind") == "deps" else "Not installed")
            QMessageBox.critical(self, "Install Failed", str(exc))
            return
        finally:
            if cleanup:
                _silent_remove(zip_path)

        if manifest.plugin_id != pid:
            self._set_row_busy(pid, False,
                               "Deps missing" if pm.get("kind") == "deps" else "Not installed")
            QMessageBox.warning(
                self, "Wrong Plugin",
                f"Expected '{pid}' but the zip contains '{manifest.plugin_id}'."
            )
            return

        remaining = self._plugin_mgr.get_missing_dependencies(pid)
        if remaining:
            self._set_row_busy(pid, False, "Deps still missing")
            QMessageBox.warning(
                self, "Dependencies Still Missing",
                "Plugin installed but these packages are still absent:\n\n"
                + "\n".join(f"  {r}" for r in remaining)
                + "\n\nRe-zip the plugin with a vendor/ folder containing its dependencies."
            )
            return

        self._status_lbls[pid].setText("✓  Ready")
        self._set_row_busy(pid, False, None)   # None = keep status as-is
        if pid in self._install_btns:
            self._install_btns[pid].setEnabled(False)
        if pid in self._download_btns:
            self._download_btns[pid].setEnabled(False)
        self._refresh_continue_btn()

    # ── Helpers ───────────────────────────────────────────────────────────

    def _set_row_busy(self, plugin_id: str, busy: bool, status_text: str | None):
        if status_text is not None:
            self._status_lbls[plugin_id].setText(status_text)
        for d in (self._install_btns, self._download_btns):
            btn = d.get(plugin_id)
            if btn:
                btn.setEnabled(not busy)
        QApplication.processEvents()

    def _refresh_continue_btn(self):
        installed_ids = {m.plugin_id for m in self._plugin_mgr.get_manifests()}
        all_resolved  = all(
            pid in installed_ids
            and not self._plugin_mgr.get_missing_dependencies(pid)
            for pid in (pm["plugin_id"] for pm in self._missing)
        )
        self._continue_btn.setText("Continue  ✓" if all_resolved else "Continue")


# ── Utilities ──────────────────────────────────────────────────────────────────

def _hline() -> QFrame:
    f = QFrame(); f.setFrameShape(QFrame.Shape.HLine)
    return f

def _silent_remove(path: str):
    try:
        os.unlink(path)
    except Exception:
        pass