ccn/Packages/Persistence/Sources/Internal/Migrations/CreateCommunity.swift

import FluentKit

/// Creates the `events`, `event_shops`, and `owned_issues` tables, seeded with the demo cons and the shops trading at them.
struct CreateCommunity: AsyncMigration {

    // MARK: Methods

    func prepare(on database: Database) async throws {
        try await database.schema(EventRecord.schema)
            .id()
            .field("slug", .string, .required)
            .field("name", .string, .required)
            .field("venue", .string, .required)
            .field("starts_on", .datetime, .required)
            .field("ends_on", .datetime, .required)
            .unique(on: "slug")
            .create()
        try await database.schema(EventShopRecord.schema)
            .id()
            .field("event_id", .uuid, .required, .references(EventRecord.schema, "id", onDelete: .cascade))
            .field("shop_id", .uuid, .required, .references(ShopRecord.schema, "id", onDelete: .cascade))
            .unique(on: "event_id", "shop_id")
            .create()
        try await database.schema(OwnedIssueRecord.schema)
            .id()
            .field("user_id", .uuid, .required, .references(UserRecord.schema, "id", onDelete: .cascade))
            .field("series_slug", .string, .required)
            .field("issue", .int, .required)
            .unique(on: "user_id", "series_slug", "issue")
            .create()

        for (event, shops) in Seed.events(after: .init()) {
            let record = EventRecord(event)

            try await record.save(on: database)

            for shop in try await ShopRecord.query(on: database).filter(\.$slug ~~ shops).all() {
                try await record.$shops.attach(shop, on: database)
            }
        }
    }

    func revert(on database: Database) async throws {
        for schema in [OwnedIssueRecord.schema, EventShopRecord.schema, EventRecord.schema] {
            try await database.schema(schema).delete()
        }
    }

}