import {Command} from "https://deno.land/x/cliffy@v0.25.7/command/mod.ts";
import {concat, partial} from 'https://deno.land/x/lodash@4.17.15-es/lodash.js';
import {join, dirname} from "https://deno.land/std@0.171.0/path/mod.ts";


enum AvroPrimitives {
  Null = "null",
  Boolean = "boolean",
  Int = "int",
  Long = "long",
  Float = "float",
  Double = "double",
  Bytes = "bytes",
  String = "string"
}

interface AvroRecordField {
  name: string,
  doc?: string,
  default?: any,
  type: AvroTypes,
}

interface AvroRecord {
  name: string,
  type: "record",
  namespace?: string,
  doc?: string,
  aliases?: string[]
  fields: AvroRecordField[]
}

interface AvroEnum {
  name: string,
  namespace?: string,
  aliases?: string[],
  type: "enum",
  symbols: string[],
}

type AvroUnion = AvroTypes[];

type AvroTypes = AvroPrimitives | AvroRecord | AvroUnion | AvroEnum;

const CacheChequeEvent: AvroRecord = {
  name: "event",
  type: "record",
  fields: [
    {name: "account", type: AvroPrimitives.Long},
  ]
}

const BogusEvent: AvroRecord = {
  name: "bogus",
  type: "record",
  fields: [
    {name: "account", type: AvroPrimitives.Long},
    {name: "foo", type: AvroPrimitives.Long},
  ]
}

const allEvents: AvroRecord[] = [CacheChequeEvent, BogusEvent]

const eventTypes: AvroEnum = {
  type: "enum",
  name: "EventType",
  symbols: allEvents.map(x => x.name),
}

const LedgerEventsSchema: AvroRecord = {
  name: "LedgerEvent",
  type: "record",
  fields: [
    {name: "event_type", type: eventTypes},
    {name: "event", type: allEvents},
  ]
};

interface CliOptions {
  dry: boolean,
  output: string,
}

type Serializer = (rec: AvroRecord) => Promise<void>;

function getOutputFileName(outputDir: string, rec: AvroRecord): string {
  return join(outputDir, rec.name + '.json');
}

async function drySerializer(outputDir: string, rec: AvroRecord): Promise<void> {
  console.log(getOutputFileName(outputDir, rec) + " : " + JSON.stringify(rec));
}

async function fileSerializer(outputDir: string, rec: AvroRecord): Promise<void> {
  let outputFile = getOutputFileName(outputDir, rec);
  await Deno.mkdir(dirname(outputFile), { recursive: true });
  await Deno.writeTextFile(outputFile, JSON.stringify(rec, null, 4));

}

function getSerializer(dry: boolean, outputDir: string): Serializer {
  return dry ? partial(drySerializer, outputDir) : partial(fileSerializer, outputDir);
}


async function main(options: CliOptions): Promise<void> {
  let serializer = getSerializer(options.dry, options.output);
  for(let e of concat([], allEvents, LedgerEventsSchema)){
   await serializer(e);
  }
}


await new Command()
.name("ledger-avro-schemata-builder")
.version("0.1.0")
.description("Build avro schemata for ledger.")
.option("--dry [value:boolean]", "Do not output any files", {
  default: false,
})
.option("--output [value:file]", "directory to output schemata", {
  default: '.',
})
.action(main)
.parse(Deno.args);