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

namespace ClankerSaddle {

    /** A task row on the task queue page, with a dependency summary. */
    public class TaskRowView : Object {
        public int64 id { get; set; }
        public string title { get; set; default = ""; }
        public string status { get; set; default = ""; }
        public string display { get; set; default = ""; }
        public bool terminal { get; set; }
        public bool failed { get; set; }
        public int64 priority { get; set; }
        public string project_name { get; set; default = ""; }
        public string dependency_summary { get; set; default = ""; }
        public bool has_dependencies { get; set; }
        public bool ready { get; set; }
        public string[] capabilities { get; set; }
        public bool waiting_for_saddle { get; set; }
        public bool unreachable { get; set; }
        /**
         * The task earned its 🤠 badge — any of its sessions carries a
         * `saddle yeehaw` entry (derived, nothing stored for it).
         */
        public bool has_yeehaw { get; set; }
        /** Plan 12: the task's work mode (badge). */
        public string mode { get; set; default = "implement"; }
        /** Plan 12: the task's creator ("human"/"goal"). */
        public string creator { get; set; default = "human"; }
        /** Plan 12: the goal the task runs under (0 = standalone). */
        public int64 goal_id { get; set; }
        public string goal_title { get; set; default = ""; }
        /** Plan 12: the auto-enqueue predecessor (0 = none). */
        public int64 enqueue_after_task_id { get; set; }
        public int64 project_id { get; set; }
    }

    /**
     * A project option in the queue page's filter and create forms,
     * carrying the default branch so the create form can prefill
     * `branch_from` as the project selection changes.
     */
    public class TaskProjectOptionView : Object {
        public int64 id { get; set; }
        public string name { get; set; default = ""; }
        public string default_branch { get; set; default = ""; }
    }

    /** Public data of the `tasks` slot. */
    public class TasksPublic : Object {
        public string filter_status { get; set; default = ""; }
        public int64 filter_project_id { get; set; }
        /** Plan 12: the goal filter ("all" | "standalone" | goal id). */
        public string filter_goal { get; set; default = "all"; }
        public Statum.Model.ActionDto? create { get; set; }
        /** The sealed GET refresh (live pulses + filter re-renders). */
        public Statum.Model.ActionDto? refresh { get; set; }
    }

    /**
     * One goal option in the queue page's filter and create forms:
     * the goal picker for the plan-12 task fan-out view.
     */
    public class GoalOptionView : Object {
        public int64 id { get; set; }
        public string title { get; set; default = ""; }
        public string status { get; set; default = ""; }
    }

    /**
     * The queue page's state builder, shared by the entrypoint and the
     * sealed refresh action (live pulse rehydration + the client-side
     * filter clicks re-render through it).
     */
    public class TasksState : Object {

        public static async Statum.Slot build(StateService state_service,
                TaskService task_service, ProjectService project_service,
                CapabilityService capability_service, SaddleService saddle_service,
                GoalService goal_service, ActionRegistry? actions,
                StatumRequest? request = null) throws GLib.Error {
            // Query filters arrive only on direct entrypoint hits (the
            // browser client's entrypoint fetch never carries the
            // page's own query string — the selects filter
            // client-side).
            string? status = null;
            if (request != null) {
                request.query.try_get_any("status", out status);
            }
            if (status == null || status.length == 0 || status == "all") {
                status = null;
            }
            string? goal_filter = null;
            if (request != null) {
                request.query.try_get_any("goal", out goal_filter);
            }
            if (goal_filter == null || goal_filter.length == 0) {
                goal_filter = "all";
            }
            int64? project_id = null;
            string? project_text = null;
            if (request != null) {
                request.query.try_get_any("project_id", out project_text);
            }
            if (project_text != null && project_text.length > 0) {
                int64 parsed = int64.parse(project_text);
                if (parsed > 0) {
                    project_id = parsed;
                }
            }

            var projects = yield project_service.list_projects();
            var project_names = new Dictionary<string, string>();
            foreach (var project in projects) {
                project_names.set(project.id.to_string(), project.name);
            }

            // ONE materialisation of the task list feeds every consumer
            // below (the status lookup, the goal-filtered strip and the
            // enqueue dropdown) — the triple list_tasks died with arch
            // item 14.
            var tasks_all = yield task_service.list_tasks(null, null);
            var statuses = new Dictionary<string, string>();
            foreach (var task in tasks_all) {
                statuses.set(task.id.to_string(), task.status);
            }
            var ready = yield task_service.get_ready_tasks();
            var ready_ids = new Invercargill.DataStructures.HashSet<string>();
            foreach (var ready_task in ready) {
                ready_ids.add(ready_task.id.to_string());
            }

            // Computed display state for every listed task (review
            // requested / delegating / suspended surface here). The
            // plan-12 goal filter narrows the list AFTER the display
            // map (the strip needs every task's display state). The
            // GoalService arrives as a parameter — an inject inside
            // this async builder would resume past an await where the
            // injection context stack is empty.
            var goal_titles = new Dictionary<string, string>();
            foreach (var goal in yield goal_service.list_goals()) {
                goal_titles.set(goal.id.to_string(), goal.title);
            }
            int64 goal_filter_id = 0;
            bool standalone_only = goal_filter == "standalone";
            if (goal_filter != "all" && !standalone_only) {
                goal_filter_id = int64.parse(goal_filter);
            }
            var listed = new Vector<ClankerSaddle.Data.TaskEntity>();
            foreach (var task in tasks_all) {
                // Goal-agent runs are internal: they never list here —
                // goals are browsed from the goal page, which alone
                // exposes the run task (its terminals, its progress).
                if (task.kind == TASK_KIND_GOAL_RUN) {
                    continue;
                }
                if (goal_filter_id > 0 && task.goal_id != goal_filter_id) {
                    continue;
                }
                if (standalone_only && task.goal_id > 0) {
                    continue;
                }
                listed.add(task);
            }
            var display_map = yield task_service.display_map_for(listed.to_immutable_buffer());

            // Capability routing context: required names per task, carried
            // names per idle saddle — a queued task waits for a capable
            // saddle when no idle saddle's set covers its requirements.
            var capability_names = new Dictionary<string, string>();
            foreach (var capability in yield capability_service.list_capabilities()) {
                capability_names.set(capability.id.to_string(), capability.name);
            }
            var required_by_task = new Dictionary<string, Vector<string>>();
            foreach (var link in yield capability_service.all_task_attachments()) {
                string name = capability_names.get_or_default(link.capability_id.to_string()) ?? "?";
                var names = required_by_task.get_or_default(link.task_id.to_string());
                if (names == null) {
                    names = new Vector<string>();
                    required_by_task.set(link.task_id.to_string(), names);
                }
                ((!)names).add(name);
            }
            var unreachable_ids = yield task_service.unreachable_task_ids();
            // The 🤠 badge's batch presence set: every task with a
            // yeehaw entry, one DISTINCT query for the whole queue.
            var yeehaw_ids = yield task_service.yeehaw_task_ids();
            var idle_capability_sets = new Vector<Invercargill.DataStructures.HashSet<string>>();
            foreach (var saddle in yield saddle_service.list_idle_saddles()) {
                var carried = new Invercargill.DataStructures.HashSet<string>();
                foreach (var link in yield capability_service.list_saddle_attachments(saddle.id)) {
                    carried.add(capability_names.get_or_default(link.capability_id.to_string()) ?? "?");
                }
                idle_capability_sets.add(carried);
            }

            var rows = new Vector<TaskRowView>();
            foreach (var task in listed) {
                var display = display_map.get_or_default(task.id.to_string());
                var view = new TaskRowView() {
                    id = task.id,
                    title = task.title,
                    status = task.status,
                    display = display != null ? ((!)display).status : task.status,
                    terminal = display != null && ((!)display).terminal,
                    failed = display != null && ((!)display).failed,
                    priority = task.priority,
                    project_id = task.project_id,
                    project_name = project_names.get_or_default(task.project_id.to_string()) ?? "",
                    mode = task.mode,
                    creator = task.creator,
                    goal_id = task.goal_id,
                    goal_title = goal_titles.get_or_default(task.goal_id.to_string()) ?? "",
                    enqueue_after_task_id = task.enqueue_after_task_id,
                    ready = ready_ids.has(task.id.to_string())
                };
                // Plan 12: the dependency summary became the
                // auto-enqueue-after predecessor note.
                if (task.enqueue_after_task_id > 0) {
                    view.has_dependencies = true;
                    view.dependency_summary = @"after #$(task.enqueue_after_task_id) (%s)".printf(
                        statuses.get_or_default(task.enqueue_after_task_id.to_string()) ?? "?");
                }
                var required = required_by_task.get_or_default(task.id.to_string());
                view.capabilities = required != null ? ((!)required).to_array() : new string[0];
                if (view.capabilities.length > 0 && task.status == STATUS_QUEUED) {
                    bool covered = false;
                    foreach (var carried in idle_capability_sets) {
                        bool missing = false;
                        foreach (var name in view.capabilities) {
                            if (!carried.has(name)) {
                                missing = true;
                                break;
                            }
                        }
                        if (!missing) {
                            covered = true;
                            break;
                        }
                    }
                    view.waiting_for_saddle = !covered && idle_capability_sets.length > 0;
                }
                view.unreachable = unreachable_ids.has(task.id.to_string());
                view.has_yeehaw = yeehaw_ids.has(task.id.to_string());
                rows.add(view);
            }

            var options = new Vector<TaskProjectOptionView>();
            foreach (var project in projects) {
                options.add(new TaskProjectOptionView() {
                    id = project.id,
                    name = project.name,
                    default_branch = project.default_branch
                });
            }

            var pub = new TasksPublic() {
                filter_status = status ?? "",
                filter_project_id = project_id != null ? ((!)project_id) : 0,
                filter_goal = goal_filter,
                create = actions != null
                    ? actions.author<CreateTaskAction>() : null,
                refresh = actions != null
                    ? actions.author<RefreshTasksDataAction>("GET") : null
            };

            var capability_options = new Vector<CapabilityOptionView>();
            foreach (var capability in yield capability_service.list_capabilities()) {
                capability_options.add(new CapabilityOptionView() {
                    id = capability.id,
                    name = capability.name
                });
            }

            // Plan 12: the goal filter's options (live goals, newest
            // status badge) and the create form's auto-enqueue-after
            // dropdown — every human-created worker task of the global
            // list (goal tasks are excluded: the goal agent sequences
            // its own).
            var goal_options = new Vector<GoalOptionView>();
            foreach (var goal in yield goal_service.list_goals()) {
                goal_options.add(new GoalOptionView() {
                    id = goal.id,
                    title = goal.title,
                    status = goal.status
                });
            }
            var enqueue_options = new Vector<TaskProjectOptionView>();
            foreach (var task in tasks_all) {
                if (task.kind != TASK_KIND_TASK || task.goal_id > 0
                        || task.creator != CREATOR_HUMAN) {
                    continue;
                }
                enqueue_options.add(new TaskProjectOptionView() {
                    id = task.id,
                    name = @"#$(task.id) $(task.title) ($(task.status))"
                });
            }

            var props = (PropertyDictionary) GObjectMapping.to_properties(pub);
            props["tasks"] = StateJson.list_rich<TaskRowView>(rows.to_immutable_buffer(),
                (item, dict) => {
                    dict["capabilities"] = StateJson.strings(
                        ((TaskRowView) item).capabilities ?? new string[0]);
                });
            props["projects"] = StateJson.list<TaskProjectOptionView>(options.to_immutable_buffer());
            props["capability_options"] = StateJson.list<CapabilityOptionView>(capability_options.to_immutable_buffer());
            props["goal_options"] = StateJson.list<GoalOptionView>(goal_options.to_immutable_buffer());
            props["enqueue_after_options"] = StateJson.list<TaskProjectOptionView>(
                enqueue_options.to_immutable_buffer());

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

    /**
     * Entrypoint for /tasks: the filterable, sortable queue. Plan 12:
     * the status/project/goal filters apply client-side (the Statum
     * entrypoint fetch carries no page query string), rows carry the
     * mode badge and goal link, and the create form offers the mode
     * select and the auto-enqueue-after dropdown. The page subscribes
     * to the global pulse and re-runs its sealed refresh action.
     */
    public class TasksEntrypoint : StatumEntrypoint {

        private TaskService task_service = Inversion.inject<TaskService>();
        private ProjectService project_service = Inversion.inject<ProjectService>();
        private CapabilityService capability_service = Inversion.inject<CapabilityService>();
        private SaddleService saddle_service = Inversion.inject<SaddleService>();
        private GoalService goal_service = Inversion.inject<GoalService>();
        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 slot = yield TasksState.build(state_service, task_service,
                project_service, capability_service, saddle_service,
                goal_service, action_registry, request);
            return directives().set(slot).subscribe_global(StatePulse.SLOT_TYPE);
        }
    }

    /**
     * The sealed GET refresh action the queue page re-runs on global
     * pulses and after a filter click (the client-side filter survives
     * the re-render in window.taskFilters).
     */
    public class RefreshTasksDataAction : StatumAction {

        private TaskService task_service = Inversion.inject<TaskService>();
        private ProjectService project_service = Inversion.inject<ProjectService>();
        private CapabilityService capability_service = Inversion.inject<CapabilityService>();
        private SaddleService saddle_service = Inversion.inject<SaddleService>();
        private GoalService goal_service = Inversion.inject<GoalService>();
        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 slot = yield TasksState.build(state_service, task_service,
                project_service, capability_service, saddle_service,
                goal_service, action_registry);
            return directives().set(slot);
        }
    }
}