using Invercargill;
using Invercargill.DataStructures;
using Invercargill.Expressions;
using Spry;
using Spry.Authentication;
using Statum;
using ClankerSaddle.Data;
using ClankerSaddle.Services;

namespace ClankerSaddle {

    /** A saddle card on the dashboard. */
    public class DashboardSaddleView : Object {
        public int64 id { get; set; }
        public string name { get; set; default = ""; }
        public string status { get; set; default = SADDLE_OFFLINE; }
        public string host { get; set; default = ""; }
        public int64 current_task_id { get; set; }
        public string current_task_title { get; set; default = ""; }
        /**
         * Set when the saddle's current task is a goal agent's run:
         * the card then links the GOAL (runs are internal — never a
         * task destination at a glance).
         */
        public int64 current_goal_id { get; set; }
        public string current_goal_title { get; set; default = ""; }
    }

    /** One entry in the dashboard's cross-task activity timeline. */
    public class DashboardActivityView : Object {
        public string kind { get; set; default = ""; }
        public int64 at_epoch { get; set; }
        public string when_display { get; set; default = ""; }
        public int64 task_id { get; set; }
        public string task_title { get; set; default = ""; }
        /** Plan 12: set on goal events — the row links the goal page. */
        public int64 goal_id { get; set; }
        public string goal_title { get; set; default = ""; }
        public string text { get; set; default = ""; }
    }

    /** An active task with its latest progress line. */
    public class DashboardActiveView : Object {
        public int64 id { get; set; }
        public string title { get; set; default = ""; }
        public string status { get; set; default = ""; }
        public string latest_progress { get; set; default = ""; }
        public string progress_display { get; set; default = ""; }
        public string task_branch { get; set; default = ""; }
    }

    /**
     * A pinned OPEN blocking item (plan 10 phase 3; plan 12 unified;
     * plan 15 C1 single-row): an unanswered question, RFC, review or
     * the goal agent's block (question/RFC, plan submission,
     * completion report — all rows of the goal-run task) rendered as
     * a link-through card. Goal items carry `item_type` "goal" and
     * link the goal page; task items carry "task" and link the task
     * page where the answer form lives. No inline answer forms on the
     * dashboard (settled).
     */
    public class DashboardBlockView : Object {
        /** "task" or "goal" — the pile interleaves both. */
        public string item_type { get; set; default = "task"; }
        public int64 id { get; set; }
        public int64 task_id { get; set; }
        public string task_title { get; set; default = ""; }
        /** Goal items only: the goal the block belongs to. */
        public int64 goal_id { get; set; }
        public string goal_title { get; set; default = ""; }
        public string block_type { get; set; default = "question"; }
        public string question { get; set; default = ""; }
        public string created_display { get; set; default = ""; }
        /** The created stamp's epoch — the unified newest-first key. */
        public int64 at_epoch { get; set; }
    }

    /** A project option in the note promote form's select. */
    public class DashboardProjectOptionView : Object {
        public int64 id { get; set; }
        public string name { get; set; default = ""; }
    }

    /**
     * A scratchpad note row on the dashboard (goal 8 task 3): the
     * body, its done state, and the per-row actions. An unpromoted,
     * undone note carries the promote action; a promoted note carries
     * its goal link instead (and never a second promote).
     */
    public class DashboardNoteView : Object {
        public int64 id { get; set; }
        public string body { get; set; default = ""; }
        public bool done { get; set; }
        public string done_display { get; set; default = ""; }
        public string created_display { get; set; default = ""; }
        /** The goal this note promoted into (0 = not promoted). */
        public int64 goal_id { get; set; }
        public string goal_title { get; set; default = ""; }
        public Statum.Model.ActionDto? toggle { get; set; }
        public Statum.Model.ActionDto? delete { get; set; }
        public Statum.Model.ActionDto? promote { get; set; }
    }

    /** Public data of the dashboard's `dashboard` slot. */
    public class DashboardPublic : Object {
        public int64 draft_count { get; set; }
        /**
         * Waiting-for-attention work (goal 2 QoL): everything the
         * system owes a dispatch or resume to — ready-to-dispatch
         * queued tasks (the ready_count subset) + parked work awaiting
         * resume (suspended tasks, suspended goal-agent runs included)
         * + tasks whose raised blocks are all answered and now wait
         * for a saddle to pick the resume up (these leave
         * blocked_count, which stays human-answerable rows only).
         * Raw queued rows gated on an unfinished auto-enqueue
         * predecessor are deliberately OUT — sequenced future work,
         * the predecessor itself is already counted.
         */
        public int64 queued_count { get; set; }
        public int64 ready_count { get; set; }
        public int64 active_count { get; set; }
        public int64 blocked_count { get; set; }
        public int64 done_count { get; set; }
        public int64 failed_count { get; set; }
        public int64 idle_saddle_count { get; set; }
        public Statum.Model.ActionDto? refresh { get; set; }
        /** The VAPID public key the browser subscribes with ("" when push is unavailable). */
        public string push_vapid_key { get; set; default = ""; }
        /** The signed-in user holds at least one push subscription. */
        public bool push_subscribed { get; set; }
        public Statum.Model.ActionDto? push_subscribe { get; set; }
        public Statum.Model.ActionDto? push_unsubscribe { get; set; }
        /** Queues a REAL test push to this user (the bell's probe). */
        public Statum.Model.ActionDto? push_test { get; set; }
        /**
         * Adds a scratchpad note (goal 8 task 3) — the Notes card's
         * add form.
         */
        public Statum.Model.ActionDto? add_note { get; set; }
    }

    /**
     * Builds the `dashboard` slot state shared by the home entrypoint and
     * the {@link RefreshDashboardAction} pulse refresh, so both hydrate
     * identical state: queue counters, saddle cards, the pinned OPEN
     * blocking items as link-through cards (newest first — plan 10
     * phase 3; goal items arrive with the run task's own blocks,
     * plan 15 C1), active tasks with their latest progress, and the
     * cross-task activity timeline ({@link TimelineService}: last ~50
     * events, newest first).
     */
    public class DashboardState : Object {

        /**
         * Loads the dashboard aggregate and shapes its PAGE slot. The
         * `db` session comes from the caller (entrypoint or action scope).
         */
        public static async Statum.Slot build(StateService state_service, TaskService tasks,
                SaddleService saddles, TimelineService timeline,
                InvercargillSql.Orm.OrmSession db, NoteService notes,
                ActionRegistry? actions = null, PushService? push = null,
                int64 viewer_id = 0) throws GLib.Error {
            var pub = new DashboardPublic();
            var titles = new Dictionary<string, string>();
            var all_tasks = yield tasks.list_tasks(null, null);
            // The ready-to-dispatch subset of the queued rows (see the
            // queued_count docblock), keyed by id so the status loop can
            // tell a dispatchable queued task from one still gated on
            // its auto-enqueue predecessor.
            var ready_ids = new HashSet<string>();
            int64 ready_count = 0;
            foreach (var ready in yield tasks.get_ready_tasks()) {
                ready_ids.add(ready.id.to_string());
                if (ready.kind != TASK_KIND_GOAL_RUN) {
                    ready_count++;
                }
            }
            pub.ready_count = ready_count;
            foreach (var task in all_tasks) {
                titles.set(task.id.to_string(), task.title);
                // Goal-agent runs are internal tasks — they never count
                // against the human-facing queue summary (the goal page
                // owns their visibility) EXCEPT parked: a suspended run
                // is goal work the system owes a resume, so it joins
                // queued_count (goal 2 QoL).
                if (task.kind == TASK_KIND_GOAL_RUN && task.status != STATUS_SUSPENDED) {
                    continue;
                }
                switch (task.status) {
                    case STATUS_DRAFT:
                        pub.draft_count++;
                        break;
                    case STATUS_QUEUED:
                        // Ready rows are the queued metric's core;
                        // predecessor-gated rows are sequenced future
                        // work the counters leave out (docblock above).
                        if (ready_ids.has(task.id.to_string())) {
                            pub.queued_count++;
                        }
                        break;
                    case STATUS_ASSIGNED:
                    case STATUS_WORKING:
                        pub.active_count++;
                        break;
                    case STATUS_SUSPENDED:
                        // Parked awaiting resume (goal 2 QoL): a
                        // suspended task waits on the system, not on a
                        // human — it reads as waiting, not blocked.
                        pub.queued_count++;
                        break;
                    case STATUS_BLOCKED:
                    case STATUS_REVIEW_REQUESTED:
                        // Goal 2 QoL: answered blocks mean the human
                        // already acted — the task now waits for a
                        // saddle to resume it, so it joins the queued
                        // metric and leaves blocked_count (which stays
                        // genuinely-needs-a-human rows).
                        if (yield blocks_all_answered(tasks, task.id)) {
                            pub.queued_count++;
                        } else {
                            pub.blocked_count++;
                        }
                        break;
                    case STATUS_DONE:
                        pub.done_count++;
                        break;
                    case STATUS_FAILED:
                        pub.failed_count++;
                        break;
                    default:
                        break;
                }
            }


            var saddle_rows = new Vector<DashboardSaddleView>();
            foreach (var saddle in yield saddles.list_saddles()) {
                // Plan 16 item 23: the card reads the DERIVED view —
                // busy iff a running session exists, else the row's
                // stored OFFLINE probe state.
                var work = yield saddles.current_work_view(saddle);
                string status = SaddleService.derived_status(saddle, work);
                if (status == SADDLE_IDLE) {
                    pub.idle_saddle_count++;
                }
                var view = new DashboardSaddleView() {
                    id = saddle.id,
                    name = saddle.name,
                    status = status,
                    host = saddle.host,
                    current_task_id = work != null ? ((!)work).task_id : 0
                };
                if (work != null) {
                    view.current_task_title = ((!)work).task_title;
                    if (((!)work).goal_id > 0) {
                        view.current_goal_id = ((!)work).goal_id;
                        view.current_goal_title = ((!)work).goal_title;
                    }
                }
                saddle_rows.add(view);
            }

            var active = new Vector<DashboardActiveView>();
            var pinned = new Vector<DashboardBlockView>();
            foreach (var task in yield tasks.list_tasks(null, null)) {
                // Goal-agent runs are internal — never an "active
                // task" row (the goal page shows the agent's
                // activity). Their BLOCKS still pin below (plan 15
                // C1): the run task's rows are the goal's pile cards.
                bool internal_run = task.kind == TASK_KIND_GOAL_RUN;
                if (!internal_run
                        && (task.status == STATUS_ASSIGNED || task.status == STATUS_WORKING
                        || task.status == STATUS_BLOCKED || task.status == STATUS_REVIEW_REQUESTED)) {
                    var row = new DashboardActiveView() {
                        id = task.id,
                        title = task.title,
                        status = task.status,
                        task_branch = task.task_branch ?? ""
                    };
                    var progress = yield tasks.list_progress(task.id);
                    if (progress.length > 0) {
                        row.latest_progress = progress.first().summary;
                        row.progress_display = format_stamp(progress.first().created_at);
                    }
                    active.add(row);
                }

                // Every unanswered block pins as a link-through card —
                // questions, RFCs and reviews alike. Plan 15 C1: the
                // goal agent's blocks ARE the run task's blocks (one
                // row each) — they render as goal items (goal badge,
                // goal link) straight from this same loop; there is no
                // goal-side pass and no mirror to consult.
                int64 block_goal_id = 0;
                string block_goal_title = "";
                if (internal_run && task.goal_id > 0) {
                    block_goal_id = task.goal_id;
                    var goal_row = yield db.query<Goal>()
                        .where(expr("id == $0", elem<int64?>(task.goal_id)))
                        .first_async();
                    block_goal_title = goal_row != null ? ((!)goal_row).title : "";
                }
                foreach (var block in yield tasks.list_blocks(task.id)) {
                    if (block.answer != null) {
                        continue;
                    }
                    var view = new DashboardBlockView() {
                        item_type = block_goal_id > 0 ? "goal" : "task",
                        id = block.id,
                        task_id = task.id,
                        task_title = task.title,
                        goal_id = block_goal_id,
                        goal_title = block_goal_title,
                        block_type = block.block_type,
                        question = block.question,
                        created_display = format_stamp(block.created_at)
                    };
                    if (block.created_at != null) {
                        view.at_epoch = ((!)block.created_at).to_unix();
                    }
                    pinned.add(view);
                }
            }
            // Newest first (plan 10 phase 3): the most recent question,
            // RFC, review or goal block leads the unified pile.
            var pinned_sorted = pinned.sort((a, b) => {
                if (a.at_epoch != b.at_epoch) {
                    return a.at_epoch > b.at_epoch ? -1 : 1;
                }
                return a.id > b.id ? -1 : 1;
            });

            if (actions != null) {
                pub.refresh = ((!)actions).author<RefreshDashboardAction>("GET");
                pub.push_subscribe = ((!)actions).author<PushSubscribeAction>();
                pub.push_unsubscribe = ((!)actions).author<PushUnsubscribeAction>();
                pub.push_test = ((!)actions).author<PushTestAction>();
                pub.add_note = ((!)actions).author<AddNoteAction>();
            }
            // Web Push bell state (plan 11 task E; per-browser since
            // the user-global flag lied to second browsers): the VAPID
            // key the browser needs, whether this user subscribed
            // anywhere (convenience), and this user's endpoint
            // FINGERPRINTS — the client compares its own subscription's
            // fingerprint against the list, so each browser shows its
            // own truth.
            pub.push_vapid_key = PushService.vapid_public_key;
            // Not a DashboardPublic property: GObjectMapping cannot
            // serialise array-shaped values, so the fingerprint list
            // rides the props dictionary like every other list here.
            string[] push_fingerprints = new string[0];
            if (push != null && viewer_id > 0) {
                pub.push_subscribed = yield ((!)push).user_subscribed(db, viewer_id);
                push_fingerprints = yield ((!)push)
                    .user_endpoint_fingerprints(db, viewer_id);
            }

            var activity = new Vector<DashboardActivityView>();
            foreach (var item in yield timeline.recent_window()) {
                activity.add(new DashboardActivityView() {
                    kind = item.kind,
                    at_epoch = item.at_epoch,
                    when_display = format_stamp(new DateTime.from_unix_local(item.at_epoch)),
                    task_id = item.task_id,
                    task_title = item.task_title,
                    goal_id = item.goal_id,
                    goal_title = item.goal_title,
                    text = item.text
                });
            }

            var props = (PropertyDictionary) GObjectMapping.to_properties(pub);
            props["saddles"] = StateJson.list<DashboardSaddleView>(saddle_rows.to_immutable_buffer());
            props["push_endpoints"] = StateJson.strings(push_fingerprints);
            props["activity"] = StateJson.list<DashboardActivityView>(activity.to_immutable_buffer());
            props["active_tasks"] = StateJson.list<DashboardActiveView>(active.to_immutable_buffer());
            props["pinned"] = StateJson.list<DashboardBlockView>(pinned_sorted.to_immutable_buffer());

            // The scratchpad (goal 8 task 3): every note with its
            // per-row sealed actions; promoted notes link their goal
            // and never carry a promote action again.
            var note_rows = new Vector<DashboardNoteView>();
            foreach (var note in yield notes.list_notes()) {
                var view = new DashboardNoteView() {
                    id = note.id,
                    body = note.body,
                    done = note.done,
                    created_display = format_stamp(note.created_at),
                    toggle = ((!)actions).author_private<ToggleNoteAction, NoteActionPrivate>(
                        new NoteActionPrivate() { note_id = note.id }),
                    delete = ((!)actions).author_private<DeleteNoteAction, NoteActionPrivate>(
                        new NoteActionPrivate() { note_id = note.id })
                };
                if (note.done_at != null) {
                    view.done_display = format_stamp(note.done_at);
                }
                if (note.goal_id > 0) {
                    view.goal_id = note.goal_id;
                    var goal_row = yield db.query<Goal>()
                        .where(expr("id == $0", elem<int64?>(note.goal_id)))
                        .first_async();
                    if (goal_row != null) {
                        view.goal_title = ((!)goal_row).title;
                    }
                } else if (!note.done) {
                    view.promote = ((!)actions).author_private<PromoteNoteAction, NoteActionPrivate>(
                        new NoteActionPrivate() { note_id = note.id });
                }
                note_rows.add(view);
            }
            props["notes"] = StateJson.list<DashboardNoteView>(note_rows.to_immutable_buffer());

            // The promote form's project options (goal 8 task 3):
            // every project, oldest first — a stable select order.
            var project_options = new Vector<DashboardProjectOptionView>();
            foreach (var project in yield db.query<Project>()
                    .order_by(expr("id"))
                    .materialise_async()) {
                project_options.add(new DashboardProjectOptionView() {
                    id = project.id,
                    name = project.name
                });
            }
            props["projects"] = StateJson.list<DashboardProjectOptionView>(
                project_options.to_immutable_buffer());

            return state_service.new_slot(Scope.PAGE, new Statum.State() {
                type_name = "dashboard",
                public_data = props,
                private_data = new PropertyDictionary()
            });
        }

        /**
         * True when the task has at least one block and every one of
         * them carries an answer (goal 2 QoL): the human already
         * acted, the dispatcher's resume is the only thing owed. A
         * task with no blocks at all is NOT answered-waiting — the
         * counters leave such rows in blocked_count untouched.
         */
        private static async bool blocks_all_answered(TaskService tasks, int64 task_id) throws GLib.Error {
            bool any = false;
            foreach (var block in yield tasks.list_blocks(task_id)) {
                any = true;
                if (block.answer == null) {
                    return false;
                }
            }
            return any;
        }
    }

    /**
     * Entrypoint for /: the dashboard — queue summary, the pinned OPEN
     * blocking items as link-through cards (newest first), active tasks
     * with their latest progress, saddle cards, and the cross-task
     * activity timeline (last ~50 events, newest first). The page
     * subscribes to the global pulse and re-runs its sealed refresh
     * action whenever task or saddle state changes anywhere in the app.
     */
    public class HomeEntrypoint : StatumEntrypoint {

        private TaskService task_service = Inversion.inject<TaskService>();
        private SaddleService saddle_service = Inversion.inject<SaddleService>();
        private TimelineService timeline_service = Inversion.inject<TimelineService>();
        private NoteService note_service = Inversion.inject<NoteService>();
        private InvercargillSql.Orm.OrmSession db = Inversion.inject<InvercargillSql.Orm.OrmSession>();
        private PushService push_service = Inversion.inject<PushService>();
        private UserService users = Inversion.inject<UserService>();

        public override async DirectiveBuilder handle() throws GLib.Error {
            var guard = yield SpryAuth.require_login(directives(), request, users);
            if (guard != null) {
                return (!)guard;
            }

            var me = SpryAuth.current(request);
            var state = yield DashboardState.build(state_service, task_service,
                saddle_service, timeline_service, db, note_service, action_registry,
                push_service, me != null ? ((!)me).user_id : 0);
            return directives().set(state).subscribe_global(StatePulse.SLOT_TYPE);
        }
    }
}