import {z} from 'zod'

export type ExternalReference = {type: string, id: string, url?: string | undefined};

export type CurrencyCode = string;

export type MonetaryAmount = {amount: string, currency: CurrencyCode};

export type ContractScope = 'FULL' | 'REVENUE_RECOGNITION_ONLY';

export type FixedRecurringPrice = {amount: MonetaryAmount, interval_months: number, type: string};

export type OneTimePrice = {amount: MonetaryAmount, type: string};

export type PerUnitBilling = {type: string, amount: MonetaryAmount, units: number};

export type Tier = {up_to: number, flat_price?: MonetaryAmount | undefined, per_unit_price?: MonetaryAmount | undefined};

export type TieredBilling = {type: string, mode: 'GRADUATED' | 'METERED', tiers: Array<Tier>};

export type BillingScheme = PerUnitBilling | TieredBilling;

export type UsagePrice = {interval_months: number, type: string, billing_scheme: BillingScheme};

export type Price = FixedRecurringPrice | OneTimePrice | UsagePrice;

export type RoundedMonetaryAmount = {amount: string, currency: CurrencyCode};

export type AmountDiscount = {amount_off: RoundedMonetaryAmount, type?: string | undefined};

export type PercentageDiscount = {percentage_off: number, type?: string | undefined};

export type Discount = AmountDiscount | PercentageDiscount;

export type FieldAssignments = Array<{field_id: string, field_value_id: string}>;

export type DraftContractItemRequest = {product_id: string, price: Price, quantity: number, discount?: Discount | undefined, start_date?: string | undefined, end_date?: string | undefined, description?: string | undefined, fields?: FieldAssignments | undefined, declared_ssp?: (MonetaryAmount | null) | undefined};

export type NullableId = string | null;

export type EmailSelectionMode = 'ALL_CUSTOMER_EMAILS' | 'SELECTED_EMAILS';

export type EmailRecipientType = 'MAIN_SENDER' | 'CC' | 'BCC';

export type EmailRecipient = {customer_email_id: string, recipient_type: EmailRecipientType};

export type EmailRecipients = Array<EmailRecipient>;

export type EmailSelection = {mode: EmailSelectionMode, recipients?: (EmailRecipients | null) | undefined};

export type CreateDraftContractRequest = {external_references?: Array<ExternalReference> | undefined, subsidiary_id: string, customer_id: string, name: string, amount: MonetaryAmount, close_date: string, start_date?: string | undefined, end_date?: string | undefined, scope: ContractScope, items: Array<DraftContractItemRequest>, purchase_order_number?: string | undefined, shipping_customer_id?: NullableId | undefined, billing_address_id?: NullableId | undefined, shipping_address_id?: NullableId | undefined, email_selection?: EmailSelection | undefined};

export type CreateApiDraftContractsArgs = {body: CreateDraftContractRequest};

export type CreateApiDraftContractsOptions = {baseUrl?: string | undefined, bearerAuth?: string | undefined, fetch?: typeof fetch | undefined};

export const externalReference = z.object({type: z.string(), id: z.string(), url: z.string().optional()});

export const currencyCode = z.string();

export const monetaryAmount = z.object({amount: z.string(), currency: currencyCode});

export const contractScope = z.enum(["FULL", "REVENUE_RECOGNITION_ONLY"]);

export const fixedRecurringPrice = z.object({amount: monetaryAmount, interval_months: z.number().int().gte(1).lte(12), type: z.string()});

export const oneTimePrice = z.object({amount: monetaryAmount, type: z.string()});

export const perUnitBilling = z.object({type: z.string(), amount: monetaryAmount, units: z.number().int().gte(1)});

export const tier = z.object({up_to: z.number().int().gte(1), flat_price: monetaryAmount.optional(), per_unit_price: monetaryAmount.optional()});

export const tieredBilling = z.object({type: z.string(), mode: z.enum(["GRADUATED", "METERED"]), tiers: z.array(tier)});

export const billingScheme = z.discriminatedUnion("type", [perUnitBilling, tieredBilling]);

export const usagePrice = z.object({interval_months: z.number().int().gte(1).lte(12), type: z.string(), billing_scheme: billingScheme});

export const price = z.discriminatedUnion("type", [fixedRecurringPrice, oneTimePrice, usagePrice]);

export const roundedMonetaryAmount = z.object({amount: z.string(), currency: currencyCode});

export const amountDiscount = z.object({amount_off: roundedMonetaryAmount, type: z.string().optional()});

export const percentageDiscount = z.object({percentage_off: z.number().gte(0).lte(100), type: z.string().optional()});

export const discount = z.discriminatedUnion("type", [amountDiscount, percentageDiscount]);

export const fieldAssignments = z.array(z.object({field_id: z.string(), field_value_id: z.string()}));

export const draftContractItem = z.object({id: z.string(), product_id: z.string(), price: price, quantity: z.string(), discount: discount.optional(), start_date: z.string().optional(), end_date: z.string().optional(), description: z.string().optional(), fields: fieldAssignments.optional(), declared_ssp: monetaryAmount.nullable().optional()});

export const countryCode = z.string();

export const customerAddress = z.object({id: z.string().optional(), line1: z.string(), line2: z.string().nullable().optional(), city: z.string(), state: z.string().nullable().optional(), zip_code: z.string(), country: countryCode});

export const emailSelectionMode = z.enum(["ALL_CUSTOMER_EMAILS", "SELECTED_EMAILS"]);

export const emailRecipientType = z.enum(["MAIN_SENDER", "CC", "BCC"]);

export const emailRecipient = z.object({customer_email_id: z.string(), recipient_type: emailRecipientType});

export const emailRecipients = z.array(emailRecipient);

export const emailSelection = z.object({mode: emailSelectionMode, recipients: emailRecipients.nullable().optional()});

export const contractApproval = z.object({approval_request_id: z.string(), operation: z.enum(["CREATE", "UPDATE"]), status: z.enum(["WAITING", "APPROVED", "REJECTED", "CANCELLED", "WITHDRAWN"]), reason: z.string().nullable().optional()});

export const draftContract = z.object({id: z.string(), external_references: z.array(externalReference), subsidiary_id: z.string(), customer_id: z.string(), name: z.string(), amount: monetaryAmount, close_date: z.string(), start_date: z.string().optional(), end_date: z.string().optional(), scope: contractScope.nullable().optional(), items: z.array(draftContractItem), purchase_order_number: z.string().optional(), shipping_customer_id: z.string().nullable().optional(), billing_address: customerAddress.nullable().optional(), shipping_address: customerAddress.nullable().optional(), email_selection: emailSelection.nullable().optional(), approval: contractApproval.nullable().optional()});

export const validateResponse = async <Output>(
  schema: {
    readonly '~standard': {
      readonly validate: (value: unknown) => ({ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }) | Promise<{ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }>
    }
  },
  value: unknown
): Promise<Output> => {
  const result = await schema['~standard'].validate(value)

  if (result.issues !== undefined) {
    const detail = result.issues
      .map(({ message, path }) =>
        path?.length
          ? `${path.map((segment) => String(typeof segment === 'object' ? segment.key : segment)).join('.')}: ${message}`
          : message
      )
      .join('; ')

    throw new Error(`Response does not match the schema: ${detail}`, { cause: { issues: result.issues } })
  }

  return result.value
};

/**
 * Creates a draft contract
 * 
 * POST /draft-contracts
 */
export const createApiDraftContracts = async (args: CreateApiDraftContractsArgs, options?: CreateApiDraftContractsOptions) => {
const {baseUrl = "https://api.rillet.com", fetch: fetchFn = fetch, bearerAuth} = options ?? {}

const query = new URLSearchParams()
const headers = new Headers()
headers.set('content-type', "application/json")
headers.set('accept', "application/json")

if (bearerAuth !== undefined) headers.set('authorization', `Bearer ${bearerAuth}`)

const url = `${baseUrl.replace(/\/+$/, '')}/draft-contracts${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "POST", headers, body: JSON.stringify(args.body)})

if (!res.ok) throw new Error(`Request failed with status ${res.status}`, {cause: {status: res.status, body: await res.text()}})

return validateResponse(draftContract, await res.json())
};