import { ResultAsync, errAsync, okAsync } from "neverthrow";
import { FlowExecCtx } from "@core/flow.execution.context";
import { traceResultAsync } from "@core/observability";
import { type Err } from "@pkg/result";
import { Database, eq } from "@pkg/db";
import { BanInfo, User } from "./data";
import { user } from "@pkg/db/schema";
import { userErrors } from "./errors";
import { logDomainEvent } from "@pkg/logger";

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

    getUserInfo(fctx: FlowExecCtx, userId: string): ResultAsync<User, Err> {
        return traceResultAsync({
            name: "logic.user.repository.getUserInfo",
            fctx,
            attributes: { "app.user.id": userId },
            fn: () => {
                const startedAt = Date.now();
                logDomainEvent({
                    event: "user.get_info.started",
                    fctx,
                    meta: { userId },
                });

                return ResultAsync.fromPromise(
                    this.db.query.user.findFirst({
                        where: eq(user.id, userId),
                    }),
                    (error) => {
                        logDomainEvent({
                            level: "error",
                            event: "user.get_info.failed",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            error,
                            meta: { userId },
                        });
                        return userErrors.getUserInfoFailed(
                            fctx,
                            error instanceof Error ? error.message : String(error),
                        );
                    },
                ).andThen((userData) => {
                    if (!userData) {
                        logDomainEvent({
                            level: "warn",
                            event: "user.get_info.failed",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            error: { code: "NOT_FOUND", message: "User not found" },
                            meta: { userId },
                        });
                        return errAsync(userErrors.userNotFound(fctx));
                    }

                    logDomainEvent({
                        event: "user.get_info.succeeded",
                        fctx,
                        durationMs: Date.now() - startedAt,
                        meta: { userId },
                    });
                    return okAsync(userData as User);
                });
            },
        });
    }

    isUsernameAvailable(
        fctx: FlowExecCtx,
        username: string,
    ): ResultAsync<boolean, Err> {
        return traceResultAsync({
            name: "logic.user.repository.isUsernameAvailable",
            fctx,
            attributes: { "app.user.username": username },
            fn: () => {
                const startedAt = Date.now();
                logDomainEvent({
                    event: "user.username_check.started",
                    fctx,
                });

                return ResultAsync.fromPromise(
                    this.db.query.user.findFirst({
                        where: eq(user.username, username),
                    }),
                    (error) => {
                        logDomainEvent({
                            level: "error",
                            event: "user.username_check.failed",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            error,
                        });
                        return userErrors.usernameCheckFailed(
                            fctx,
                            error instanceof Error ? error.message : String(error),
                        );
                    },
                ).map((existingUser) => {
                    const isAvailable = !existingUser?.id;
                    logDomainEvent({
                        event: "user.username_check.succeeded",
                        fctx,
                        durationMs: Date.now() - startedAt,
                        meta: { isAvailable },
                    });
                    return isAvailable;
                });
            },
        });
    }

    updateLastVerified2FaAtToNow(
        fctx: FlowExecCtx,
        userId: string,
    ): ResultAsync<boolean, Err> {
        return traceResultAsync({
            name: "logic.user.repository.updateLastVerified2FaAtToNow",
            fctx,
            attributes: { "app.user.id": userId },
            fn: () => {
                const startedAt = Date.now();
                logDomainEvent({
                    event: "user.update_last_2fa.started",
                    fctx,
                    meta: { userId },
                });

                return ResultAsync.fromPromise(
                    this.db
                        .update(user)
                        .set({ last2FAVerifiedAt: new Date() })
                        .where(eq(user.id, userId))
                        .execute(),
                    (error) => {
                        logDomainEvent({
                            level: "error",
                            event: "user.update_last_2fa.failed",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            error,
                            meta: { userId },
                        });
                        return userErrors.updateFailed(
                            fctx,
                            error instanceof Error ? error.message : String(error),
                        );
                    },
                ).map(() => {
                    logDomainEvent({
                        event: "user.update_last_2fa.succeeded",
                        fctx,
                        durationMs: Date.now() - startedAt,
                        meta: { userId },
                    });
                    return true;
                });
            },
        });
    }

    banUser(
        fctx: FlowExecCtx,
        userId: string,
        reason: string,
        banExpiresAt: Date,
    ): ResultAsync<boolean, Err> {
        return traceResultAsync({
            name: "logic.user.repository.banUser",
            fctx,
            attributes: { "app.user.id": userId },
            fn: () => {
                const startedAt = Date.now();
                logDomainEvent({
                    event: "user.ban.started",
                    fctx,
                    meta: {
                        userId,
                        reasonLength: reason.length,
                        banExpiresAt: banExpiresAt.toISOString(),
                    },
                });

                return ResultAsync.fromPromise(
                    this.db
                        .update(user)
                        .set({
                            banned: true,
                            banReason: reason,
                            banExpires: banExpiresAt,
                        })
                        .where(eq(user.id, userId))
                        .execute(),
                    (error) => {
                        logDomainEvent({
                            level: "error",
                            event: "user.ban.failed",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            error,
                            meta: { userId },
                        });
                        return userErrors.banOperationFailed(
                            fctx,
                            error instanceof Error ? error.message : String(error),
                        );
                    },
                ).map(() => {
                    logDomainEvent({
                        event: "user.ban.succeeded",
                        fctx,
                        durationMs: Date.now() - startedAt,
                        meta: { userId },
                    });
                    return true;
                });
            },
        });
    }

    isUserBanned(fctx: FlowExecCtx, userId: string): ResultAsync<boolean, Err> {
        return traceResultAsync({
            name: "logic.user.repository.isUserBanned",
            fctx,
            attributes: { "app.user.id": userId },
            fn: () => {
                const startedAt = Date.now();
                logDomainEvent({
                    event: "user.is_banned.started",
                    fctx,
                    meta: { userId },
                });

                return ResultAsync.fromPromise(
                    this.db.query.user.findFirst({
                        where: eq(user.id, userId),
                        columns: {
                            banned: true,
                            banExpires: true,
                        },
                    }),
                    (error) => {
                        logDomainEvent({
                            level: "error",
                            event: "user.is_banned.failed",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            error,
                            meta: { userId },
                        });
                        return userErrors.dbError(
                            fctx,
                            error instanceof Error ? error.message : String(error),
                        );
                    },
                ).andThen((userData) => {
                    if (!userData) {
                        logDomainEvent({
                            level: "warn",
                            event: "user.is_banned.failed",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            error: { code: "NOT_FOUND", message: "User not found" },
                            meta: { userId },
                        });
                        return errAsync(userErrors.userNotFound(fctx));
                    }

                    if (!userData.banned) {
                        logDomainEvent({
                            event: "user.is_banned.succeeded",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            meta: { userId, isBanned: false },
                        });
                        return okAsync(false);
                    }

                    if (!userData.banExpires) {
                        logDomainEvent({
                            event: "user.is_banned.succeeded",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            meta: { userId, isBanned: true, isPermanent: true },
                        });
                        return okAsync(true);
                    }

                    const now = new Date();
                    if (userData.banExpires <= now) {
                        return ResultAsync.fromPromise(
                            this.db
                                .update(user)
                                .set({
                                    banned: false,
                                    banReason: null,
                                    banExpires: null,
                                })
                                .where(eq(user.id, userId))
                                .execute(),
                            (error) => {
                                logDomainEvent({
                                    level: "error",
                                    event: "user.unban_after_expiry.failed",
                                    fctx,
                                    durationMs: Date.now() - startedAt,
                                    error,
                                    meta: { userId },
                                });
                                return userErrors.unbanFailed(
                                    fctx,
                                    error instanceof Error
                                        ? error.message
                                        : String(error),
                                );
                            },
                        )
                            .map(() => {
                                logDomainEvent({
                                    event: "user.unban_after_expiry.succeeded",
                                    fctx,
                                    durationMs: Date.now() - startedAt,
                                    meta: { userId },
                                });
                                return false;
                            })
                            .orElse((error) => {
                                logDomainEvent({
                                    level: "warn",
                                    event: "user.is_banned.succeeded",
                                    fctx,
                                    durationMs: Date.now() - startedAt,
                                    error,
                                    meta: { userId, degraded: true, isBanned: true },
                                });
                                return okAsync(true);
                            });
                    }

                    logDomainEvent({
                        event: "user.is_banned.succeeded",
                        fctx,
                        durationMs: Date.now() - startedAt,
                        meta: {
                            userId,
                            isBanned: true,
                            banExpires: userData.banExpires.toISOString(),
                        },
                    });
                    return okAsync(true);
                });
            },
        });
    }

    getBanInfo(fctx: FlowExecCtx, userId: string): ResultAsync<BanInfo, Err> {
        return traceResultAsync({
            name: "logic.user.repository.getBanInfo",
            fctx,
            attributes: { "app.user.id": userId },
            fn: () => {
                const startedAt = Date.now();
                logDomainEvent({
                    event: "user.ban_info.started",
                    fctx,
                    meta: { userId },
                });

                return ResultAsync.fromPromise(
                    this.db.query.user.findFirst({
                        where: eq(user.id, userId),
                        columns: { banned: true, banReason: true, banExpires: true },
                    }),
                    (error) => {
                        logDomainEvent({
                            level: "error",
                            event: "user.ban_info.failed",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            error,
                            meta: { userId },
                        });
                        return userErrors.getBanInfoFailed(
                            fctx,
                            error instanceof Error ? error.message : String(error),
                        );
                    },
                ).andThen((userData) => {
                    if (!userData) {
                        logDomainEvent({
                            level: "warn",
                            event: "user.ban_info.failed",
                            fctx,
                            durationMs: Date.now() - startedAt,
                            error: { code: "NOT_FOUND", message: "User not found" },
                            meta: { userId },
                        });
                        return errAsync(userErrors.userNotFound(fctx));
                    }

                    logDomainEvent({
                        event: "user.ban_info.succeeded",
                        fctx,
                        durationMs: Date.now() - startedAt,
                        meta: { userId, banned: userData.banned || false },
                    });

                    return okAsync({
                        banned: userData.banned || false,
                        reason: userData.banReason || undefined,
                        expires: userData.banExpires || undefined,
                    });
                });
            },
        });
    }
}