# Copyright: Ankitects Pty Ltd and contributors
# -*- coding: utf-8 -*-
# License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
import io
import json
import re
import zipfile
from collections import defaultdict
from typing import Callable, Dict, Any

import markdown
from send2trash import send2trash
import jsonschema
from jsonschema.exceptions import ValidationError

from aqt.qt import *
from aqt.utils import showInfo, openFolder, isWin, openLink, \
    askUser, restoreGeom, saveGeom, restoreSplitter, saveSplitter, \
    showWarning, tooltip, getFile
from zipfile import ZipFile
import aqt.forms
import aqt
from aqt.downloader import download
from anki.lang import _, ngettext
from anki.utils import intTime
from anki.sync import AnkiRequestsClient

class AddonManager:

    ext = ".ankiaddon"
    _manifest_schema = {
        "type": "object",
        "properties": {
            "package": {"type": "string", "meta": False},
            "name": {"type": "string", "meta": True},
            "mod": {"type": "number", "meta": True},
            "conflicts": {
                "type": "array",
                "items": {"type": "string"},
                "meta": True
            }
        },
        "required": ["package", "name"]
    }

    def __init__(self, mw):
        self.mw = mw
        self.dirty = False
        f = self.mw.form
        f.actionAdd_ons.triggered.connect(self.onAddonsDialog)
        sys.path.insert(0, self.addonsFolder())

    def allAddons(self):
        l = []
        for d in os.listdir(self.addonsFolder()):
            path = self.addonsFolder(d)
            if not os.path.exists(os.path.join(path, "__init__.py")):
                continue
            l.append(d)
        l.sort()
        if os.getenv("ANKIREVADDONS", ""):
            l = reversed(l)
        return l

    def managedAddons(self):
        return [d for d in self.allAddons()
                if re.match(r"^\d+$", d)]

    def addonsFolder(self, dir=None):
        root = self.mw.pm.addonFolder()
        if not dir:
            return root
        return os.path.join(root, dir)

    def loadAddons(self):
        for dir in self.allAddons():
            meta = self.addonMeta(dir)
            if meta.get("disabled"):
                continue
            self.dirty = True
            try:
                __import__(dir)
            except:
                showWarning(_("""\
An add-on you installed failed to load. If problems persist, please \
go to the Tools>Add-ons menu, and disable or delete the add-on.

When loading '%(name)s':
%(traceback)s
""") % dict(name=meta.get("name", dir), traceback=traceback.format_exc()))

    def onAddonsDialog(self):
        AddonsDialog(self)

    # Metadata
    ######################################################################

    def _addonMetaPath(self, dir):
        return os.path.join(self.addonsFolder(dir), "meta.json")

    def addonMeta(self, dir):
        path = self._addonMetaPath(dir)
        try:
            with open(path, encoding="utf8") as f:
                return json.load(f)
        except:
            return dict()

    def writeAddonMeta(self, dir, meta):
        path = self._addonMetaPath(dir)
        with open(path, "w", encoding="utf8") as f:
            json.dump(meta, f)

    def isEnabled(self, dir):
        meta = self.addonMeta(dir)
        return not meta.get('disabled')

    def toggleEnabled(self, dir, enable=None):
        meta = self.addonMeta(dir)
        enabled = enable if enable is not None else meta.get("disabled")
        if enabled is True:
            conflicting = self._disableConflicting(dir)
            if conflicting:
                addons = ", ".join(self.addonName(f) for f in conflicting)
                showInfo(
                    _("The following add-ons are incompatible with %(name)s \
and have been disabled: %(found)s") % dict(name=self.addonName(dir), found=addons),
                    textFormat="plain")

        meta['disabled'] = not enabled
        self.writeAddonMeta(dir, meta)

    def addonName(self, dir):
        return self.addonMeta(dir).get("name", dir)

    def annotatedName(self, dir):
        buf = self.addonName(dir)
        if not self.isEnabled(dir):
            buf += _(" (disabled)")
        return buf

    # Conflict resolution
    ######################################################################

    def addonConflicts(self, dir):
        return self.addonMeta(dir).get("conflicts", [])

    def allAddonConflicts(self):
        all_conflicts = defaultdict(list)
        for dir in self.allAddons():
            if not self.isEnabled(dir):
                continue
            conflicts = self.addonConflicts(dir)
            for other_dir in conflicts:
                all_conflicts[other_dir].append(dir)
        return all_conflicts

    def _disableConflicting(self, dir, conflicts=None):
        conflicts = conflicts or self.addonConflicts(dir)

        installed = self.allAddons()
        found = [d for d in conflicts if d in installed and self.isEnabled(d)]
        found.extend(self.allAddonConflicts().get(dir, []))
        if not found:
            return []

        for package in found:
            self.toggleEnabled(package, enable=False)
        
        return found

    # Installing and deleting add-ons
    ######################################################################

    def readManifestFile(self, zfile):
        try:
            with zfile.open("manifest.json") as f:
                data = json.loads(f.read())
            jsonschema.validate(data, self._manifest_schema)
            # build new manifest from recognized keys
            schema = self._manifest_schema["properties"]
            manifest = {key: data[key] for key in data.keys() & schema.keys()}
        except (KeyError, json.decoder.JSONDecodeError, ValidationError):
            # raised for missing manifest, invalid json, missing/invalid keys
            return {}
        return manifest

    def install(self, file, manifest=None):
        """Install add-on from path or file-like object. Metadata is read
        from the manifest file, with keys overriden by supplying a 'manifest'
        dictionary"""
        try:
            zfile = ZipFile(file)
        except zipfile.BadZipfile:
            return False, "zip"
        
        with zfile:
            file_manifest = self.readManifestFile(zfile)
            if manifest:
                file_manifest.update(manifest)
            manifest = file_manifest
            if not manifest:
                return False, "manifest"
            package = manifest["package"]
            conflicts = manifest.get("conflicts", [])
            found_conflicts = self._disableConflicting(package,
                                                       conflicts)
            meta = self.addonMeta(package)
            self._install(package, zfile)
        
        schema = self._manifest_schema["properties"]
        manifest_meta = {k: v for k, v in manifest.items()
                         if k in schema and schema[k]["meta"]}
        meta.update(manifest_meta)
        self.writeAddonMeta(package, meta)

        return True, meta["name"], found_conflicts

    def _install(self, dir, zfile):
        # previously installed?
        base = self.addonsFolder(dir)
        if os.path.exists(base):
            self.backupUserFiles(dir)
            if not self.deleteAddon(dir):
                self.restoreUserFiles(dir)
                return

        os.mkdir(base)
        self.restoreUserFiles(dir)

        # extract
        for n in zfile.namelist():
            if n.endswith("/"):
                # folder; ignore
                continue

            path = os.path.join(base, n)
            # skip existing user files
            if os.path.exists(path) and n.startswith("user_files/"):
                continue
            zfile.extract(n, base)

    # true on success
    def deleteAddon(self, dir):
        try:
            send2trash(self.addonsFolder(dir))
            return True
        except OSError as e:
            showWarning(_("Unable to update or delete add-on. Please start Anki while holding down the shift key to temporarily disable add-ons, then try again.\n\nDebug info: %s") % e,
                        textFormat="plain")
            return False

    # Processing local add-on files
    ######################################################################
    
    def processPackages(self, paths):
        log = []
        errs = []
        self.mw.progress.start(immediate=True)
        try:
            for path in paths:
                base = os.path.basename(path)
                ret = self.install(path)
                if ret[0] is False:
                    if ret[1] == "zip":
                        msg = _("Corrupt add-on file.")
                    elif ret[1] == "manifest":
                        msg = _("Invalid add-on manifest.")
                    else:
                        msg = "Unknown error: {}".format(ret[1])
                    errs.append(_("Error installing <i>%(base)s</i>: %(error)s"
                                  % dict(base=base, error=msg)))
                else:
                    log.append(_("Installed %(name)s" % dict(name=ret[1])))
                    if ret[2]:
                        log.append(_("The following conflicting add-ons were disabled:") + " " + " ".join(ret[2]))
        finally:
            self.mw.progress.finish()
        return log, errs

    # Downloading
    ######################################################################

    def downloadIds(self, ids):
        log = []
        errs = []
        self.mw.progress.start(immediate=True)
        for n in ids:
            ret = download(self.mw, n)
            if ret[0] == "error":
                errs.append(_("Error downloading %(id)s: %(error)s") % dict(id=n, error=ret[1]))
                continue
            data, fname = ret
            fname = fname.replace("_", " ")
            name = os.path.splitext(fname)[0]
            ret = self.install(io.BytesIO(data),
                               manifest={"package": str(n), "name": name,
                                         "mod": intTime()})
            if ret[0] is False:
                if ret[1] == "zip":
                    msg = _("Corrupt add-on file.")
                elif ret[1] == "manifest":
                    msg = _("Invalid add-on manifest.")
                else:
                    msg = "Unknown error: {}".format(ret[1])
                errs.append(_("Error downloading %(id)s: %(error)s") % dict(
                    id=n, error=msg))
            else:
                log.append(_("Downloaded %(fname)s" % dict(fname=name)))
                if ret[2]:
                    log.append(_("The following conflicting add-ons were disabled:") + " " + " ".join(ret[2]))

        self.mw.progress.finish()
        return log, errs

    # Updating
    ######################################################################

    def checkForUpdates(self):
        client = AnkiRequestsClient()

        # get mod times
        self.mw.progress.start(immediate=True)
        try:
            # ..of enabled items downloaded from ankiweb
            addons = []
            for dir in self.managedAddons():
                meta = self.addonMeta(dir)
                if not meta.get("disabled"):
                    addons.append(dir)

            mods = []
            while addons:
                chunk = addons[:25]
                del addons[:25]
                mods.extend(self._getModTimes(client, chunk))
            return self._updatedIds(mods)
        finally:
            self.mw.progress.finish()

    def _getModTimes(self, client, chunk):
        resp = client.get(
            aqt.appShared + "updates/" + ",".join(chunk))
        if resp.status_code == 200:
            return resp.json()
        else:
            raise Exception("Unexpected response code from AnkiWeb: {}".format(resp.status_code))

    def _updatedIds(self, mods):
        updated = []
        for dir, ts in mods:
            sid = str(dir)
            if self.addonMeta(sid).get("mod", 0) < (ts or 0):
                updated.append(sid)
        return updated

    # Add-on Config
    ######################################################################

    _configButtonActions: Dict[str, Callable[[], None]] = {}
    _configUpdatedActions: Dict[str, Callable[[Any], None]] = {}

    def addonConfigDefaults(self, dir):
        path = os.path.join(self.addonsFolder(dir), "config.json")
        try:
            with open(path, encoding="utf8") as f:
                return json.load(f)
        except:
            return None

    def addonConfigHelp(self, dir):
        path = os.path.join(self.addonsFolder(dir), "config.md")
        if os.path.exists(path):
            with open(path, encoding="utf-8") as f:
                return markdown.markdown(f.read())
        else:
            return ""

    def addonFromModule(self, module):
        return module.split(".")[0]

    def configAction(self, addon):
        return self._configButtonActions.get(addon)

    def configUpdatedAction(self, addon):
        return self._configUpdatedActions.get(addon)

    # Add-on Config API
    ######################################################################

    def getConfig(self, module):
        addon = self.addonFromModule(module)
        # get default config
        config = self.addonConfigDefaults(addon)
        if config is None:
            return None
        # merge in user's keys
        meta = self.addonMeta(addon)
        userConf = meta.get("config", {})
        config.update(userConf)
        return config

    def setConfigAction(self, module, fn):
        addon = self.addonFromModule(module)
        self._configButtonActions[addon] = fn

    def setConfigUpdatedAction(self, module, fn):
        addon = self.addonFromModule(module)
        self._configUpdatedActions[addon] = fn

    def writeConfig(self, module, conf):
        addon = self.addonFromModule(module)
        meta = self.addonMeta(addon)
        meta['config'] = conf
        self.writeAddonMeta(addon, meta)

    # user_files
    ######################################################################

    def _userFilesPath(self, sid):
        return os.path.join(self.addonsFolder(sid), "user_files")

    def _userFilesBackupPath(self):
        return os.path.join(self.addonsFolder(), "files_backup")

    def backupUserFiles(self, sid):
        p = self._userFilesPath(sid)
        if os.path.exists(p):
            os.rename(p, self._userFilesBackupPath())

    def restoreUserFiles(self, sid):
        p = self._userFilesPath(sid)
        bp = self._userFilesBackupPath()
        # did we back up userFiles?
        if not os.path.exists(bp):
            return
        os.rename(bp, p)
    
    # Web Exports
    ######################################################################

    _webExports: Dict[str, str] = {}

    def setWebExports(self, module, pattern):
        addon = self.addonFromModule(module)
        self._webExports[addon] = pattern
    
    def getWebExports(self, addon):
        return self._webExports.get(addon)


# Add-ons Dialog
######################################################################

class AddonsDialog(QDialog):

    def __init__(self, addonsManager):
        self.mgr = addonsManager
        self.mw = addonsManager.mw

        super().__init__(self.mw)

        f = self.form = aqt.forms.addons.Ui_Dialog()
        f.setupUi(self)
        f.getAddons.clicked.connect(self.onGetAddons)
        f.installFromFile.clicked.connect(self.onInstallFiles)
        f.checkForUpdates.clicked.connect(self.onCheckForUpdates)
        f.toggleEnabled.clicked.connect(self.onToggleEnabled)
        f.viewPage.clicked.connect(self.onViewPage)
        f.viewFiles.clicked.connect(self.onViewFiles)
        f.delete_2.clicked.connect(self.onDelete)
        f.config.clicked.connect(self.onConfig)
        self.form.addonList.itemDoubleClicked.connect(self.onConfig)
        self.form.addonList.currentRowChanged.connect(self._onAddonItemSelected)
        self.setAcceptDrops(True)
        self.redrawAddons()
        restoreGeom(self, "addons")
        self.show()

    def dragEnterEvent(self, event):
        mime = event.mimeData()
        if not mime.hasUrls():
            return None
        urls = mime.urls()
        ext = self.mgr.ext
        if all(url.toLocalFile().endswith(ext) for url in urls):
            event.acceptProposedAction()

    def dropEvent(self, event):
        mime = event.mimeData()
        paths = []
        for url in mime.urls():
            path = url.toLocalFile()
            if os.path.exists(path):
                paths.append(path)
        self.onInstallFiles(paths)

    def reject(self):
        saveGeom(self, "addons")
        return QDialog.reject(self)

    def redrawAddons(self):
        addonList = self.form.addonList
        mgr = self.mgr
        
        self.addons = [(mgr.annotatedName(d), d) for d in mgr.allAddons()]
        self.addons.sort()

        selected = set(self.selectedAddons())
        addonList.clear()
        for name, dir in self.addons:
            item = QListWidgetItem(name, addonList)
            if not mgr.isEnabled(dir):
                item.setForeground(Qt.gray)
            if dir in selected:
                item.setSelected(True)

        addonList.repaint()

    def _onAddonItemSelected(self, row_int):
        try:
            addon = self.addons[row_int][1]
        except IndexError:
            addon = ''
        self.form.viewPage.setEnabled(bool(re.match(r"^\d+$", addon)))
        self.form.config.setEnabled(bool(self.mgr.getConfig(addon) or
                                         self.mgr.configAction(addon)))

    def selectedAddons(self):
        idxs = [x.row() for x in self.form.addonList.selectedIndexes()]
        return [self.addons[idx][1] for idx in idxs]

    def onlyOneSelected(self):
        dirs = self.selectedAddons()
        if len(dirs) != 1:
            showInfo(_("Please select a single add-on first."))
            return
        return dirs[0]

    def onToggleEnabled(self):
        for dir in self.selectedAddons():
            self.mgr.toggleEnabled(dir)
        self.redrawAddons()

    def onViewPage(self):
        addon = self.onlyOneSelected()
        if not addon:
            return
        if re.match(r"^\d+$", addon):
            openLink(aqt.appShared + "info/{}".format(addon))
        else:
            showWarning(_("Add-on was not downloaded from AnkiWeb."))

    def onViewFiles(self):
        # if nothing selected, open top level folder
        selected = self.selectedAddons()
        if not selected:
            openFolder(self.mgr.addonsFolder())
            return

        # otherwise require a single selection
        addon = self.onlyOneSelected()
        if not addon:
            return
        path = self.mgr.addonsFolder(addon)
        openFolder(path)

    def onDelete(self):
        selected = self.selectedAddons()
        if not selected:
            return
        if not askUser(ngettext("Delete the %(num)d selected add-on?",
                                "Delete the %(num)d selected add-ons?",
                                len(selected)) %
                               dict(num=len(selected))):
            return
        for dir in selected:
            if not self.mgr.deleteAddon(dir):
                break
        self.form.addonList.clearSelection()
        self.redrawAddons()

    def onGetAddons(self):
        GetAddons(self)

    def onInstallFiles(self, paths=None):
        if not paths:
            key = (_("Packaged Anki Add-on") + " (*{})".format(self.mgr.ext))
            paths = getFile(self, _("Install Add-on(s)"), None, key,
                            key="addons", multi=True)
            if not paths:
                return False
        
        log, errs = self.mgr.processPackages(paths)

        if log:
            log_html = "<br>".join(log)
            if len(log) == 1:
                tooltip(log_html, parent=self)
            else:
                showInfo(log_html, parent=self, textFormat="rich")
        if errs:
            msg = _("Please report this to the respective add-on author(s).")
            showWarning("<br><br>".join(errs + [msg]), parent=self, textFormat="rich")

        self.redrawAddons()

    def onCheckForUpdates(self):
        try:
            updated = self.mgr.checkForUpdates()
        except Exception as e:
            showWarning(_("Please check your internet connection.") + "\n\n" + str(e),
                        textFormat="plain")
            return

        if not updated:
            tooltip(_("No updates available."))
        else:
            names = [self.mgr.addonName(d) for d in updated]
            if askUser(_("Update the following add-ons?") +
                               "\n" + "\n".join(names)):
                log, errs = self.mgr.downloadIds(updated)
                if log:
                    log_html = "<br>".join(log)
                    if len(log) == 1:
                        tooltip(log_html, parent=self)
                    else:
                        showInfo(log_html, parent=self, textFormat="rich")
                if errs:
                    showWarning("\n\n".join(errs), parent=self, textFormat="plain")

                self.redrawAddons()

    def onConfig(self):
        addon = self.onlyOneSelected()
        if not addon:
            return

        # does add-on manage its own config?
        act = self.mgr.configAction(addon)
        if act:
            act()
            return

        conf = self.mgr.getConfig(addon)
        if conf is None:
            showInfo(_("Add-on has no configuration."))
            return

        ConfigEditor(self, addon, conf)


# Fetching Add-ons
######################################################################

class GetAddons(QDialog):

    def __init__(self, dlg):
        QDialog.__init__(self, dlg)
        self.addonsDlg = dlg
        self.mgr = dlg.mgr
        self.mw = self.mgr.mw
        self.form = aqt.forms.getaddons.Ui_Dialog()
        self.form.setupUi(self)
        b = self.form.buttonBox.addButton(
            _("Browse Add-ons"), QDialogButtonBox.ActionRole)
        b.clicked.connect(self.onBrowse)
        restoreGeom(self, "getaddons", adjustSize=True)
        self.exec_()
        saveGeom(self, "getaddons")

    def onBrowse(self):
        openLink(aqt.appShared + "addons/2.1")

    def accept(self):
        # get codes
        try:
            ids = [int(n) for n in self.form.code.text().split()]
        except ValueError:
            showWarning(_("Invalid code."))
            return

        log, errs = self.mgr.downloadIds(ids)

        if log:
            log_html = "<br>".join(log)
            if len(log) == 1:
                tooltip(log_html, parent=self)
            else:
                showInfo(log_html, parent=self, textFormat="rich")
        if errs:
            showWarning("\n\n".join(errs), textFormat="plain")

        self.addonsDlg.redrawAddons()
        QDialog.accept(self)

# Editing config
######################################################################

class ConfigEditor(QDialog):

    def __init__(self, dlg, addon, conf):
        super().__init__(dlg)
        self.addon = addon
        self.conf = conf
        self.mgr = dlg.mgr
        self.form = aqt.forms.addonconf.Ui_Dialog()
        self.form.setupUi(self)
        restore = self.form.buttonBox.button(QDialogButtonBox.RestoreDefaults)
        restore.clicked.connect(self.onRestoreDefaults)
        self.setupFonts()
        self.updateHelp()
        self.updateText(self.conf)
        restoreGeom(self, "addonconf")
        restoreSplitter(self.form.splitter, "addonconf")
        self.show()

    def onRestoreDefaults(self):
        default_conf = self.mgr.addonConfigDefaults(self.addon)
        self.updateText(default_conf)
        tooltip(_("Restored defaults"), parent=self)

    def setupFonts(self):
        font_mono = QFontDatabase.systemFont(QFontDatabase.FixedFont)
        font_mono.setPointSize(font_mono.pointSize() + 1)
        self.form.editor.setFont(font_mono)

    def updateHelp(self):
        txt = self.mgr.addonConfigHelp(self.addon)
        if txt:
            self.form.label.setText(txt)
        else:
            self.form.scrollArea.setVisible(False)

    def updateText(self, conf):
        self.form.editor.setPlainText(
            json.dumps(conf, ensure_ascii=False, sort_keys=True,
                       indent=4, separators=(',', ': ')))

    def onClose(self):
        saveGeom(self, "addonconf")
        saveSplitter(self.form.splitter, "addonconf")

    def reject(self):
        self.onClose()
        super().reject()

    def accept(self):
        txt = self.form.editor.toPlainText()
        try:
            new_conf = json.loads(txt)
        except Exception as e:
            showInfo(_("Invalid configuration: ") + repr(e))
            return

        if not isinstance(new_conf, dict):
            showInfo(_("Invalid configuration: top level object must be a map"))
            return

        if new_conf != self.conf:
            self.mgr.writeConfig(self.addon, new_conf)
            # does the add-on define an action to be fired?
            act = self.mgr.configUpdatedAction(self.addon)
            if act:
                act(new_conf)
        
        self.onClose()
        super().accept()