import Foundation

final class MemoryPayeeStorage: PayeeStorage {
    var data: Data?
    var failRead = false
    var failWrite = false
    var failDelete = false

    func read() throws -> Data? {
        if failRead { throw PayeeFailure(message: "Read failed") }
        return data
    }

    func write(_ value: Data) throws {
        if failWrite { throw PayeeFailure(message: "Write failed") }
        data = value
    }

    func delete() throws {
        if failDelete { throw PayeeFailure(message: "Delete failed") }
        data = nil
    }
}

@main
struct PayeeProfileTests {
    @MainActor static func main() throws {
        let storage = MemoryPayeeStorage()
        let store = PayeeProfileStore(storage: storage)
        precondition(store.profile == nil && store.loadError == nil)
        let empty = try store.exportFields()
        precondition(empty.isEmpty)
        precondition((try? PayeeProfile().validated()) == nil)
        let draft = PayeeProfile(recipient: " 测试收款人 ", bankName: " 测试银行支行 ",
                                 accountNumber: " 0012 3456 7890 ", preparer: "")
        try store.save(draft)
        precondition(store.profile?.accountNumber == "001234567890")
        precondition(store.profile?.recipient == "测试收款人")
        precondition(store.profile?.exportFields["preparer"] == "测试收款人")
        let restored = PayeeProfileStore(storage: storage)
        precondition(restored.profile == store.profile)
        var changed = draft
        changed.preparer = "测试制单人"
        try store.save(changed)
        precondition(store.profile?.exportFields["preparer"] == "测试制单人")
        let saved = store.profile
        let savedData = storage.data
        storage.failWrite = true
        do {
            try store.save(draft)
            preconditionFailure("Failed storage must not report success")
        } catch {}
        precondition(store.profile == saved && storage.data == savedData)
        storage.failWrite = false
        storage.failDelete = true
        do {
            try store.clear()
            preconditionFailure("Failed delete must retain profile")
        } catch {}
        precondition(store.profile == saved)
        storage.failDelete = false
        try store.clear()
        precondition(storage.data == nil && store.profile == nil)
        try store.save(draft)
        storage.failRead = true
        store.reload()
        precondition(store.profile == nil && store.loadError != nil)
        precondition((try? store.exportFields()) == nil)
        precondition((try? store.save(draft)) == nil)
        storage.failRead = false
        store.reload()
        precondition(store.profile != nil && store.loadError == nil)
        storage.data = Data("corrupt".utf8)
        store.reload()
        precondition(store.loadError != nil && store.profile == nil)
        var invalid = draft
        invalid.bankName = String(repeating: "行", count: 201)
        precondition((try? invalid.validated()) == nil)
        invalid = draft
        invalid.recipient = "测试\n收款人"
        precondition((try? invalid.validated()) == nil)
        print("Payee profile validation, persistence, update, delete and failure tests passed")
    }
}