import { and, asc, count, Database, desc, eq, like, or, sql } from "@pkg/db";
import { notifications } from "@pkg/db/schema";
import { ResultAsync } from "neverthrow";
import { FlowExecCtx } from "@core/flow.execution.context";
import type {
    Notification,
    NotificationFilters,
    PaginatedNotifications,
    PaginationOptions,
} from "./data";
import { type Err } from "@pkg/result";
import { notificationErrors } from "./errors";
import { logDomainEvent } from "@pkg/logger";

export class NotificationRepository {
    constructor(private db: Database) {}

    getNotifications(
        fctx: FlowExecCtx,
        filters: NotificationFilters,
        pagination: PaginationOptions,
    ): ResultAsync<PaginatedNotifications, Err> {
        const startedAt = Date.now();
        logDomainEvent({
            event: "notifications.list.started",
            fctx,
            meta: {
                hasSearch: Boolean(filters.search),
                isRead: filters.isRead,
                isArchived: filters.isArchived,
                page: pagination.page,
                pageSize: pagination.pageSize,
                sortBy: pagination.sortBy,
                sortOrder: pagination.sortOrder,
            },
        });

        const { userId, isRead, isArchived, type, category, priority, search } =
            filters;
        const {
            page,
            pageSize,
            sortBy = "createdAt",
            sortOrder = "desc",
        } = pagination;

        // Build WHERE conditions
        const conditions = [eq(notifications.userId, userId)];

        if (isRead !== undefined) {
            conditions.push(eq(notifications.isRead, isRead));
        }

        if (isArchived !== undefined) {
            conditions.push(eq(notifications.isArchived, isArchived));
        }

        if (type) {
            conditions.push(eq(notifications.type, type));
        }

        if (category) {
            conditions.push(eq(notifications.category, category));
        }

        if (priority) {
            conditions.push(eq(notifications.priority, priority));
        }

        if (search) {
            conditions.push(
                or(
                    like(notifications.title, `%${search}%`),
                    like(notifications.body, `%${search}%`),
                )!,
            );
        }

        const whereClause = and(...conditions);

        return ResultAsync.fromPromise(
            this.db.select({ count: count() }).from(notifications).where(whereClause),
            (error) => {
                logDomainEvent({
                    level: "error",
                    event: "notifications.list.failed",
                    fctx,
                    durationMs: Date.now() - startedAt,
                    error,
                });
                return notificationErrors.getNotificationsFailed(
                    fctx,
                    error instanceof Error ? error.message : String(error),
                );
            },
        ).andThen((totalResult) => {
            const total = totalResult[0]?.count || 0;
            const offset = (page - 1) * pageSize;

            // Map sortBy to proper column
            const getOrderColumn = (sortBy: string) => {
                switch (sortBy) {
                    case "createdAt":
                        return notifications.createdAt;
                    case "sentAt":
                        return notifications.sentAt;
                    case "readAt":
                        return notifications.readAt;
                    case "priority":
                        return notifications.priority;
                    default:
                        return notifications.createdAt;
                }
            };

            const orderColumn = getOrderColumn(sortBy);
            const orderFunc = sortOrder === "asc" ? asc : desc;

            return ResultAsync.fromPromise(
                this.db
                    .select()
                    .from(notifications)
                    .where(whereClause)
                    .orderBy(orderFunc(orderColumn))
                    .limit(pageSize)
                    .offset(offset),
                (error) => {
                    logDomainEvent({
                        level: "error",
                        event: "notifications.list.failed",
                        fctx,
                        durationMs: Date.now() - startedAt,
                        error,
                    });
                    return notificationErrors.getNotificationsFailed(
                        fctx,
                        error instanceof Error ? error.message : String(error),
                    );
                },
            ).map((data) => {
                const totalPages = Math.ceil(total / pageSize);
                logDomainEvent({
                    event: "notifications.list.succeeded",
                    fctx,
                    durationMs: Date.now() - startedAt,
                    meta: {
                        count: data.length,
                        page,
                        totalPages,
                    },
                });

                return {
                    data: data as Notification[],
                    total,
                    page,
                    pageSize,
                    totalPages,
                };
            });
        });
    }

    markAsRead(
        fctx: FlowExecCtx,
        notificationIds: number[],
        userId: string,
    ): ResultAsync<boolean, Err> {
        const startedAt = Date.now();
        logDomainEvent({
            event: "notifications.mark_read.started",
            fctx,
            meta: { userId, notificationCount: notificationIds.length },
        });

        return ResultAsync.fromPromise(
            this.db
                .update(notifications)
                .set({
                    isRead: true,
                    readAt: new Date(),
                    updatedAt: new Date(),
                })
                .where(
                    and(
                        eq(notifications.userId, userId),
                        sql`${notifications.id} = ANY(${notificationIds})`,
                    ),
                ),
            (error) => {
                logDomainEvent({
                    level: "error",
                    event: "notifications.mark_read.failed",
                    fctx,
                    durationMs: Date.now() - startedAt,
                    error,
                });
                return notificationErrors.markAsReadFailed(
                    fctx,
                    error instanceof Error ? error.message : String(error),
                );
            },
        ).map(() => {
            logDomainEvent({
                event: "notifications.mark_read.succeeded",
                fctx,
                durationMs: Date.now() - startedAt,
                meta: { notificationCount: notificationIds.length },
            });
            return true;
        });
    }

    markAsUnread(
        fctx: FlowExecCtx,
        notificationIds: number[],
        userId: string,
    ): ResultAsync<boolean, Err> {
        const startedAt = Date.now();
        logDomainEvent({
            event: "notifications.mark_unread.started",
            fctx,
            meta: { userId, notificationCount: notificationIds.length },
        });

        return ResultAsync.fromPromise(
            this.db
                .update(notifications)
                .set({
                    isRead: false,
                    readAt: null,
                    updatedAt: new Date(),
                })
                .where(
                    and(
                        eq(notifications.userId, userId),
                        sql`${notifications.id} = ANY(${notificationIds})`,
                    ),
                ),
            (error) => {
                logDomainEvent({
                    level: "error",
                    event: "notifications.mark_unread.failed",
                    fctx,
                    durationMs: Date.now() - startedAt,
                    error,
                });
                return notificationErrors.markAsUnreadFailed(
                    fctx,
                    error instanceof Error ? error.message : String(error),
                );
            },
        ).map(() => {
            logDomainEvent({
                event: "notifications.mark_unread.succeeded",
                fctx,
                durationMs: Date.now() - startedAt,
                meta: { notificationCount: notificationIds.length },
            });
            return true;
        });
    }

    archive(
        fctx: FlowExecCtx,
        notificationIds: number[],
        userId: string,
    ): ResultAsync<boolean, Err> {
        const startedAt = Date.now();
        logDomainEvent({
            event: "notifications.archive.started",
            fctx,
            meta: { userId, notificationCount: notificationIds.length },
        });

        return ResultAsync.fromPromise(
            this.db
                .update(notifications)
                .set({
                    isArchived: true,
                    updatedAt: new Date(),
                })
                .where(
                    and(
                        eq(notifications.userId, userId),
                        sql`${notifications.id} = ANY(${notificationIds})`,
                    ),
                ),
            (error) => {
                logDomainEvent({
                    level: "error",
                    event: "notifications.archive.failed",
                    fctx,
                    durationMs: Date.now() - startedAt,
                    error,
                });
                return notificationErrors.archiveFailed(
                    fctx,
                    error instanceof Error ? error.message : String(error),
                );
            },
        ).map(() => {
            logDomainEvent({
                event: "notifications.archive.succeeded",
                fctx,
                durationMs: Date.now() - startedAt,
                meta: { notificationCount: notificationIds.length },
            });
            return true;
        });
    }

    unarchive(
        fctx: FlowExecCtx,
        notificationIds: number[],
        userId: string,
    ): ResultAsync<boolean, Err> {
        const startedAt = Date.now();
        logDomainEvent({
            event: "notifications.unarchive.started",
            fctx,
            meta: { userId, notificationCount: notificationIds.length },
        });

        return ResultAsync.fromPromise(
            this.db
                .update(notifications)
                .set({
                    isArchived: false,
                    updatedAt: new Date(),
                })
                .where(
                    and(
                        eq(notifications.userId, userId),
                        sql`${notifications.id} = ANY(${notificationIds})`,
                    ),
                ),
            (error) => {
                logDomainEvent({
                    level: "error",
                    event: "notifications.unarchive.failed",
                    fctx,
                    durationMs: Date.now() - startedAt,
                    error,
                });
                return notificationErrors.unarchiveFailed(
                    fctx,
                    error instanceof Error ? error.message : String(error),
                );
            },
        ).map(() => {
            logDomainEvent({
                event: "notifications.unarchive.succeeded",
                fctx,
                durationMs: Date.now() - startedAt,
                meta: { notificationCount: notificationIds.length },
            });
            return true;
        });
    }

    deleteNotifications(
        fctx: FlowExecCtx,
        notificationIds: number[],
        userId: string,
    ): ResultAsync<boolean, Err> {
        const startedAt = Date.now();
        logDomainEvent({
            event: "notifications.delete.started",
            fctx,
            meta: { userId, notificationCount: notificationIds.length },
        });

        return ResultAsync.fromPromise(
            this.db
                .delete(notifications)
                .where(
                    and(
                        eq(notifications.userId, userId),
                        sql`${notifications.id} = ANY(${notificationIds})`,
                    ),
                ),
            (error) => {
                logDomainEvent({
                    level: "error",
                    event: "notifications.delete.failed",
                    fctx,
                    durationMs: Date.now() - startedAt,
                    error,
                });
                return notificationErrors.deleteNotificationsFailed(
                    fctx,
                    error instanceof Error ? error.message : String(error),
                );
            },
        ).map(() => {
            logDomainEvent({
                event: "notifications.delete.succeeded",
                fctx,
                durationMs: Date.now() - startedAt,
                meta: { notificationCount: notificationIds.length },
            });
            return true;
        });
    }

    getUnreadCount(
        fctx: FlowExecCtx,
        userId: string,
    ): ResultAsync<number, Err> {
        const startedAt = Date.now();
        logDomainEvent({
            event: "notifications.unread_count.started",
            fctx,
            meta: { userId },
        });

        return ResultAsync.fromPromise(
            this.db
                .select({ count: count() })
                .from(notifications)
                .where(
                    and(
                        eq(notifications.userId, userId),
                        eq(notifications.isRead, false),
                        eq(notifications.isArchived, false),
                    ),
                ),
            (error) => {
                logDomainEvent({
                    level: "error",
                    event: "notifications.unread_count.failed",
                    fctx,
                    durationMs: Date.now() - startedAt,
                    error,
                });
                return notificationErrors.getUnreadCountFailed(
                    fctx,
                    error instanceof Error ? error.message : String(error),
                );
            },
        ).map((result) => {
            const count = result[0]?.count || 0;
            logDomainEvent({
                event: "notifications.unread_count.succeeded",
                fctx,
                durationMs: Date.now() - startedAt,
                meta: { count },
            });
            return count;
        });
    }
}