import $ from "jquery";
import cockpit from "cockpit";

var mod = { };

var known_hosts_path = "/etc/ssh/ssh_known_hosts";
/*
 * We share the Machines state between multiple frames. Only
 * one frame has the job of loading the state, usually index.js
 * The Loader code below does all the loading.
 *
 * The data is stored in sessionStorage in a JSON object, like this
 * {
 *    content: name → info dict from bridge's /machines Machines property
 *    overlay: extra data to augment and override on top of content
 * }
 *
 * This uses sessionStorage rather than cockpit.sessionStorage
 * because we don't ever want to write unprefixed keys.
 */

var key = cockpit.sessionStorage.prefixedKey("v2-machines.json");
var session_prefix = cockpit.sessionStorage.prefixedKey("v1-session-machine");

function generate_session_key(host) {
    return session_prefix + "/" + host;
}

function Machines() {
    var self = this;

    var flat = null;
    self.ready = false;

    /* parsed machine data */
    var machines = { };

    /* Data shared between Machines() instances */
    var last = {
        content: null,
        overlay: {
            localhost: {
                visible: true,
                manifests: cockpit.manifests
            }
        }
    };

    function storage(ev) {
        if (ev.key === key && ev.storageArea === window.sessionStorage)
            refresh(JSON.parse(ev.newValue || "null"));
    }

    window.addEventListener("storage", storage);

    window.setTimeout(function() {
        var value = window.sessionStorage.getItem(key);
        if (!self.ready && value)
            refresh(JSON.parse(value));
    });

    var timeout = null;

    function sync(machine, values, overlay) {
        var desired = $.extend({ }, values || { }, overlay || { });
        var prop;
        for (prop in desired) {
            if (machine[prop] !== desired[prop])
                machine[prop] = desired[prop];
        }
        for (prop in machine) {
            if (machine[prop] !== desired[prop])
                delete machine[prop];
        }
        return machine;
    }

    function refresh(shared, push) {
        if (!shared)
            return;

        var emit_ready = !self.ready;

        self.ready = true;
        last = shared;
        flat = null;

        if (push && !timeout) {
            timeout = window.setTimeout(function() {
                timeout = null;
                window.sessionStorage.setItem(key, JSON.stringify(last));
            }, 10);
        }

        var host;
        var hosts = { };
        var content = shared.content || { };
        var overlay = shared.overlay || { };
        for (host in content)
            hosts[host] = true;
        for (host in overlay)
            hosts[host] = true;

        var events = [];

        var machine, application;
        for (host in hosts) {
            var old_machine = machines[host] || { };
            var old_conns = old_machine.connection_string;

            /* Invert logic for color, always respect what's on disk */
            if (content[host] && content[host].color && overlay[host])
                delete overlay[host].color;

            machine = sync(old_machine, content[host], overlay[host]);

            /* Fill in defaults */
            machine.key = host;
            if (!machine.address)
                machine.address = host;

            machine.connection_string = self.generate_connection_string(machine.user,
                                                                        machine.port,
                                                                        machine.address);

            if (!machine.label) {
                if (host == "localhost" || host == "localhost.localdomain") {
                    application = cockpit.transport.application();
                    if (application.indexOf('cockpit+=') === 0)
                        machine.label = application.replace('cockpit+=', '');
                    else
                        machine.label = window.location.hostname;
                } else {
                    machine.label = host;
                }
            }
            if (!machine.avatar)
                machine.avatar = "../shell/images/server-small.png";

            events.push([host in machines ? "updated" : "added",
                [machine, host, old_conns]]);
            machines[host] = machine;
        }

        /* Remove any lost hosts */
        for (host in machines) {
            if (!(host in hosts)) {
                machine = machines[host];
                delete machines[host];
                delete overlay[host];
                events.push(["removed", [machine, host]]);
            }
        }

        /* Fire off all events */
        var i;
        var sel = $(self);
        var len = events.length;
        for (i = 0; i < len; i++)
            sel.triggerHandler(events[i][0], events[i][1]);
        if (emit_ready)
            $(self).triggerHandler("ready");
    }

    function update_session_machine(machine, host, values) {
        /* We don't save the whole machine object */
        var skey = generate_session_key(host);
        var data = $.extend({}, machine, values);
        window.sessionStorage.setItem(skey, JSON.stringify(data));
        self.overlay(host, values);
        return cockpit.when([]);
    }

    function update_saved_machine(host, values) {
        // wrap values in variants for D-Bus call; at least values.port can
        // be int or string, so stringify everything but the "visible" boolean
        var values_variant = {};
        for (var prop in values) {
            if (values[prop] !== null) {
                if (prop == "visible")
                    values_variant[prop] = cockpit.variant('b', values[prop]);
                else
                    values_variant[prop] = cockpit.variant('s', values[prop].toString());
            }
        }

        // FIXME: investigate re-using the proxy from Loader (runs in different frame/scope)
        var bridge = cockpit.dbus(null, { bus: "internal", superuser: "try" });
        var mod = bridge.call("/machines", "cockpit.Machines", "Update", ["99-webui.json", host, values_variant])
                .fail(function(error) {
                    console.error("failed to call cockpit.Machines.Update(): ", error);
                });

        return mod;
    }

    self.add_key = function(host_key) {
        var known_hosts = cockpit.file(known_hosts_path, { superuser: "try" });
        return known_hosts
                .modify(function(data) {
                    if (!data)
                        data = "";

                    return data + "\n" + host_key;
                })
                .always(function() {
                    known_hosts.close();
                });
    };

    self.add = function add(connection_string, color) {
        var values = self.split_connection_string(connection_string);
        var host = values.address;

        values = $.extend({
            visible: true,
            color: color || self.unused_color(),
        }, values);

        var machine = self.lookup(host);
        if (machine)
            machine.on_disk = true;

        return self.change(values.address, values);
    };

    self.unused_color = function unused_color() {
        var i;
        var len = mod.colors.length;
        for (i = 0; i < len; i++) {
            if (!color_in_use(mod.colors[i]))
                return mod.colors[i];
        }
        return "gray";
    };

    function color_in_use(color) {
        var key, machine;
        var norm = mod.colors.parse(color);
        for (key in machines) {
            machine = machines[key];
            if (machine.color && mod.colors.parse(machine.color) == norm)
                return true;
        }
        return false;
    }

    function merge(item, values) {
        for (var prop in values) {
            if (values[prop] === null)
                delete item[prop];
            else
                item[prop] = values[prop];
        }
    }

    self.change = function change(host, values) {
        var mod, hostnamed, call;
        var machine = self.lookup(host);

        if (values.label) {
            var conn_to = host;
            if (machine)
                conn_to = machine.connection_string;

            if (!machine || machine.label !== values.label) {
                hostnamed = cockpit.dbus("org.freedesktop.hostname1", { host: conn_to, superuser: "try" });
                call = hostnamed.call("/org/freedesktop/hostname1", "org.freedesktop.hostname1",
                                      "SetPrettyHostname", [values.label, true])
                        .always(function() {
                            hostnamed.close();
                        })
                        .fail(function(ex) {
                            console.warn("couldn't set pretty host name: " + ex);
                        });
            }
        }

        if (machine && !machine.on_disk)
            mod = update_session_machine(machine, host, values);
        else
            mod = update_saved_machine(host, values);

        if (call)
            // Can't use Promise.all() here, because this promise is sometimes
            // passed to the dialog() function from pkg/lib/patterns.js, which
            // expects a promise with a progress() method
            // eslint-disable-next-line cockpit/no-cockpit-all
            return cockpit.all([call, mod]);

        return mod;
    };

    self.data = function data(content) {
        var host;
        var changes = {};

        for (host in content) {
            changes[host] = $.extend({ }, last.overlay[host] || { });
            merge(changes[host], { on_disk: true });
        }

        /* It's a full reload, so data not
         * present is no longer from disk
         */
        for (host in machines) {
            if (content && !content[host]) {
                changes[host] = $.extend({ }, last.overlay[host] || { });
                merge(changes[host], { on_disk: null });
            }
        }

        refresh({
            content: content,
            overlay: $.extend({ }, last.overlay, changes)
        }, true);
    };

    self.overlay = function overlay(host, values) {
        var changes = { };
        changes[host] = $.extend({ }, last.overlay[host] || { });
        merge(changes[host], values);
        refresh({
            content: last.content,
            overlay: $.extend({ }, last.overlay, changes)
        }, true);
    };

    Object.defineProperty(self, "list", {
        enumerable: true,
        get: function get() {
            var key;
            if (!flat) {
                flat = [];
                for (key in machines) {
                    if (machines[key].visible)
                        flat.push(machines[key]);
                }
                flat.sort(function(m1, m2) {
                    return m1.label.localeCompare(m2.label);
                });
            }
            return flat;
        }
    });

    Object.defineProperty(self, "addresses", {
        enumerable: true,
        get: function get() {
            return Object.keys(machines);
        }
    });

    self.lookup = function lookup(address) {
        var parts = self.split_connection_string(address);
        return machines[parts.address || "localhost"] || null;
    };

    self.generate_connection_string = function (user, port, addr) {
        var address = addr;
        if (user)
            address = user + "@" + address;

        if (port)
            address = address + ":" + port;

        return address;
    };

    self.split_connection_string = function(conn_to) {
        var parts = {};
        var user_spot = -1;
        var port_spot = -1;

        if (conn_to) {
            user_spot = conn_to.lastIndexOf('@');
            port_spot = conn_to.lastIndexOf(':');
        }

        if (user_spot > 0) {
            parts.user = conn_to.substring(0, user_spot);
            conn_to = conn_to.substring(user_spot + 1);
            port_spot = conn_to.lastIndexOf(':');
        }

        if (port_spot > -1) {
            var port = parseInt(conn_to.substring(port_spot + 1), 10);
            if (!isNaN(port)) {
                parts.port = port;
                conn_to = conn_to.substring(0, port_spot);
            }
        }

        parts.address = conn_to;
        return parts;
    };

    self.close = function close() {
        window.removeEventListener("storage", storage);
    };
}

function Loader(machines, session_only) {
    var self = this;

    /* Have we loaded from cockpit session */
    var session_loaded = false;

    /* echo channels to each machine */
    var channels = { };

    /* hostnamed proxies to each machine, if hostnamed available */
    var proxies = { };

    /* clients for the bridge D-Bus API */
    var bridge_dbus = { };

    function process_session_key(key, value) {
        var host, values, machine;
        var parts = key.split("/");
        if (parts[0] == session_prefix &&
            parts.length === 2) {
            host = parts[1];
            if (value) {
                values = JSON.parse(value);
                machine = machines.lookup(host);
                if (!machine || !machine.on_disk)
                    machines.overlay(host, values);
                else if (!machine.visible)
                    machines.change(host, { visible: true });
                self.connect(host);
            }
        }
    }

    function load_from_session_storage() {
        var i;
        session_loaded = true;
        for (i = 0; i < window.sessionStorage.length; i++) {
            var k = window.sessionStorage.key(i);
            process_session_key(k, window.sessionStorage.getItem(k));
        }
    }

    function process_session_machines(ev) {
        if (ev.storageArea === window.sessionStorage)
            process_session_key(ev.key || "", ev.newValue);
    }
    window.addEventListener("storage", process_session_machines);

    function state(host, value, problem) {
        var values = { state: value, problem: problem };
        if (value == "connected") {
            values.restarting = false;
        } else if (problem) {
            values.manifests = null;
            values.checksum = null;
        }
        machines.overlay(host, values);
    }

    $(machines).on("added", updated);
    $(machines).on("updated", updated);
    $(machines).on("removed", removed);

    function updated(ev, machine, host, old_conns) {
        if (!machine) {
            machine = machines.lookup(host);
            if (!machine)
                return;
        }

        var props = proxies[host];
        if (!props || !props.valid)
            props = { };

        var overlay = { };

        if (!machine.color)
            overlay.color = machines.unused_color();

        var label = props.PrettyHostname || props.StaticHostname;
        if (label && label !== machine.label)
            overlay.label = label;

        var os = props.OperatingSystemPrettyName;
        if (os && os != machine.os)
            overlay.os = props.OperatingSystemPrettyName;

        if (!$.isEmptyObject(overlay))
            machines.overlay(host, overlay);

        /* Don't automatically reconnect failed machines */
        if (machine.visible) {
            if (old_conns && machine.connection_string != old_conns) {
                cockpit.kill(old_conns);
                self.disconnect(host);
                self.connect(host);
            } else if (!machine.problem) {
                self.connect(host);
            }
        } else {
            self.disconnect(host);
        }
    }

    function removed(ev, machine, host) {
        self.disconnect(host);
    }

    self.connect = function connect(host) {
        var machine = machines.lookup(host);
        if (!machine)
            return;

        var channel = channels[host];
        if (channel)
            return;

        var options = {
            host: machine.connection_string,
            payload: "echo"
        };

        if (!machine.on_disk && machine.host_key) {
            options['temp-session'] = false; /* Compatibility option */
            options.session = 'shared';
            options['host-key'] = machine.host_key;
        }

        channel = cockpit.channel(options);
        channels[host] = channel;

        var local = host === "localhost";

        /* Request is null, and message is true when connected */
        var request = null;
        var open = local;
        var problem = null;

        var url;
        if (!machine.manifests) {
            if (machine.checksum)
                url = "../../" + machine.checksum + "/manifests.json";
            else
                url = "../../@" + encodeURI(machine.connection_string) + "/manifests.json";
        }

        function whirl() {
            if (!request && open)
                state(host, "connected", null);
            else if (!problem)
                state(host, "connecting", null);
        }

        /* Here we load the machine manifests, and expect them before going to "connected" */
        function request_manifest() {
            request = $.ajax({ url: url, dataType: "json", cache: true })
                    .done(function(manifests) {
                        var overlay = { manifests: manifests };
                        var etag = request.getResponseHeader("ETag");
                        if (etag) /* and remove quotes */
                            overlay.checksum = etag.replace(/^"(.+)"$/, '$1');
                        machines.overlay(host, overlay);
                    })
                    .fail(function(ex) {
                        console.warn("failed to load manifests from " + machine.connection_string + ": " + ex);
                    })
                    .always(function() {
                        request = null;
                        whirl();
                    });
        }

        /* Try to get change notifications via the internal
           /packages D-Bus interface of the bridge.  Not all
           bridges support this API, so we still get the first
           version of the manifests via HTTP in request_manifest.
        */

        function watch_manifests() {
            var dbus = cockpit.dbus(null, {
                bus: "internal",
                host: machine.connection_string
            });
            bridge_dbus[host] = dbus;
            dbus.subscribe({
                path: "/packages",
                interface: "org.freedesktop.DBus.Properties",
                member: "PropertiesChanged"
            },
                           function (path, iface, mamber, args) {
                               if (args[0] == "cockpit.Packages") {
                                   if (args[1].Manifests) {
                                       var manifests = JSON.parse(args[1].Manifests.v);
                                       machines.overlay(host, { manifests: manifests });
                                   }
                               }
                           });

            /* Tell the bridge to reload the packages, but only if
               it hasn't just started.  Thus, nothing happens on
               the first login, but if you reload the shell, we
               will also reload the packages.
            */
            dbus.call("/packages", "cockpit.Packages", "ReloadHint", []);
        }

        function request_hostname() {
            if (!machine.static_hostname) {
                var proxy = cockpit.dbus("org.freedesktop.hostname1",
                                         { host: machine.connection_string }).proxy();
                proxies[host] = proxy;
                proxy.wait(function() {
                    $(proxy).on("changed", function() {
                        updated(null, null, host);
                    });
                    updated(null, null, host);
                });
            }
        }

        /* Send a message to the server and get back a message once connected */
        if (!local) {
            channel.send("x");

            $(channel)
                    .on("message", function() {
                        open = true;
                        if (url)
                            request_manifest();
                        watch_manifests();
                        request_hostname();
                        whirl();
                    })
                    .on("close", function(ev, options) {
                        var m = machines.lookup(host);
                        open = false;
                        // reset to clean state when removing machine (orderly disconnect), otherwise mark as failed
                        if (!options.problem && m && !m.visible)
                            state(host, null, null);
                        else
                            state(host, "failed", options.problem || "disconnected");
                        if (m && m.restarting) {
                            window.setTimeout(function() {
                                self.connect(host);
                            }, 10000);
                        }
                        self.disconnect(host);
                    });
        } else {
            if (url)
                request_manifest();
            watch_manifests();
            request_hostname();
        }

        /* In case already ready, for example when local */
        whirl();
    };

    self.disconnect = function disconnect(host) {
        if (host === "localhost")
            return;

        var channel = channels[host];
        delete channels[host];
        if (channel) {
            channel.close();
            $(channel).off();
        }

        var proxy = proxies[host];
        delete proxies[host];
        if (proxy) {
            proxy.client.close();
            $(proxy).off();
        }

        var dbus = bridge_dbus[host];
        delete bridge_dbus[host];
        if (dbus) {
            dbus.close();
        }
    };

    self.expect_restart = function expect_restart(host) {
        var parts = machines.split_connection_string(host);
        machines.overlay(parts.address, {
            restarting: true,
            problem: null
        });
    };

    self.close = function close() {
        $(machines).off("added", updated);
        $(machines).off("changed", updated);
        $(machines).off("removed", removed);
        machines = null;

        window.removeEventListener("storage", process_session_machines);
        var hosts = Object.keys(channels);
        hosts.forEach(self.disconnect);
    };

    if (!session_only) {
        var proxy = cockpit.dbus(null, { bus: "internal" }).proxy("cockpit.Machines", "/machines");
        $(proxy).on("changed", function(data) {
            // unwrap variants from D-Bus call
            var wrapped = proxy.Machines;
            var data_unwrap = {};
            var host_props;
            for (var host in wrapped) {
                host_props = {};
                for (var prop in wrapped[host])
                    host_props[prop] = wrapped[host][prop].v;
                data_unwrap[host] = host_props;
            }

            machines.data(data_unwrap);
            if (!session_loaded)
                load_from_session_storage();
        });
    } else {
        load_from_session_storage();
        machines.data({});
    }
}

mod.instance = function instance(loader) {
    return new Machines();
};

mod.loader = function loader(machines, session_only) {
    return new Loader(machines, session_only);
};

mod.colors = [
    "#0099d3",
    "#67d300",
    "#d39e00",
    "#d3007c",
    "#00d39f",
    "#00d1d3",
    "#00618a",
    "#4c8a00",
    "#8a6600",
    "#9b005b",
    "#008a55",
    "#008a8a",
    "#00b9ff",
    "#7dff00",
    "#ffbe00",
    "#ff0096",
    "#00ffc0",
    "#00fdff",
    "#023448",
    "#264802",
    "#483602",
    "#590034",
    "#024830",
    "#024848"
];

mod.colors.parse = function parse_color(input) {
    var div = document.createElement('div');
    div.style.color = input;
    var style = window.getComputedStyle(div, null);
    return style.getPropertyValue("color") || div.style.color;
};

mod.known_hosts_path = known_hosts_path;

cockpit.transport.wait(function() {
    var caps = cockpit.transport.options.capabilities || [];
    /* If cockpit-ws is handling ssh, check for each capability. Otherwise
     * the version is new enough that is has them all */
    if ($.inArray("ssh", caps) > -1) {
        mod.allow_connection_string = $.inArray("connection-string", caps) != -1;
        mod.has_auth_results = $.inArray("auth-method-results", caps) != -1;
        known_hosts_path = "/var/lib/cockpit/known_hosts";
        mod.known_hosts_path = known_hosts_path;
        console.debug("Running against legacy ws with ssh, using legacy file", known_hosts_path);
    } else {
        mod.allow_connection_string = true;
        mod.has_auth_results = true;
    }
});

export const machines = mod;
