import { Oid } from "./oid.js";
import {
  decodeBigint,
  decodeBigintArray,
  decodeBoolean,
  decodeBooleanArray,
  decodeBox,
  decodeBoxArray,
  decodeBytea,
  decodeByteaArray,
  decodeCircle,
  decodeCircleArray,
  decodeDate,
  decodeDateArray,
  decodeDatetime,
  decodeDatetimeArray,
  decodeInt,
  decodeIntArray,
  decodeJson,
  decodeJsonArray,
  decodeLine,
  decodeLineArray,
  decodeLineSegment,
  decodeLineSegmentArray,
  decodePath,
  decodePathArray,
  decodePoint,
  decodePointArray,
  decodePolygon,
  decodePolygonArray,
  decodeStringArray,
  decodeTid,
  decodeTidArray,
} from "./decoders.js";

export class Column {
  constructor(
    public name: string,
    public tableOid: number,
    public index: number,
    public typeOid: number,
    public columnLength: number,
    public typeModifier: number,
    public format: Format,
  ) {}
}

enum Format {
  TEXT = 0,
  BINARY = 1,
}

const decoder = new TextDecoder();

// TODO
// Decode binary fields
function decodeBinary() {
  throw new Error("Not implemented!");
}

// deno-lint-ignore no-explicit-any
function decodeText(value: Uint8Array, typeOid: number): any {
  const strValue = decoder.decode(value);

  switch (typeOid) {
    case Oid.bpchar:
    case Oid.char:
    case Oid.cidr:
    case Oid.float4:
    case Oid.float8:
    case Oid.inet:
    case Oid.macaddr:
    case Oid.name:
    case Oid.numeric:
    case Oid.oid:
    case Oid.regclass:
    case Oid.regconfig:
    case Oid.regdictionary:
    case Oid.regnamespace:
    case Oid.regoper:
    case Oid.regoperator:
    case Oid.regproc:
    case Oid.regprocedure:
    case Oid.regrole:
    case Oid.regtype:
    case Oid.text:
    case Oid.time:
    case Oid.timetz:
    case Oid.uuid:
    case Oid.varchar:
    case Oid.void:
      return strValue;
    case Oid.bpchar_array:
    case Oid.char_array:
    case Oid.cidr_array:
    case Oid.float4_array:
    case Oid.float8_array:
    case Oid.inet_array:
    case Oid.macaddr_array:
    case Oid.name_array:
    case Oid.numeric_array:
    case Oid.oid_array:
    case Oid.regclass_array:
    case Oid.regconfig_array:
    case Oid.regdictionary_array:
    case Oid.regnamespace_array:
    case Oid.regoper_array:
    case Oid.regoperator_array:
    case Oid.regproc_array:
    case Oid.regprocedure_array:
    case Oid.regrole_array:
    case Oid.regtype_array:
    case Oid.text_array:
    case Oid.time_array:
    case Oid.timetz_array:
    case Oid.uuid_array:
    case Oid.varchar_array:
      return decodeStringArray(strValue);
    case Oid.int2:
    case Oid.int4:
    case Oid.xid:
      return decodeInt(strValue);
    case Oid.int2_array:
    case Oid.int4_array:
    case Oid.xid_array:
      return decodeIntArray(strValue);
    case Oid.bool:
      return decodeBoolean(strValue);
    case Oid.bool_array:
      return decodeBooleanArray(strValue);
    case Oid.box:
      return decodeBox(strValue);
    case Oid.box_array:
      return decodeBoxArray(strValue);
    case Oid.circle:
      return decodeCircle(strValue);
    case Oid.circle_array:
      return decodeCircleArray(strValue);
    case Oid.bytea:
      return decodeBytea(strValue);
    case Oid.byte_array:
      return decodeByteaArray(strValue);
    case Oid.date:
      return decodeDate(strValue);
    case Oid.date_array:
      return decodeDateArray(strValue);
    case Oid.int8:
      return decodeBigint(strValue);
    case Oid.int8_array:
      return decodeBigintArray(strValue);
    case Oid.json:
    case Oid.jsonb:
      return decodeJson(strValue);
    case Oid.json_array:
    case Oid.jsonb_array:
      return decodeJsonArray(strValue);
    case Oid.line:
      return decodeLine(strValue);
    case Oid.line_array:
      return decodeLineArray(strValue);
    case Oid.lseg:
      return decodeLineSegment(strValue);
    case Oid.lseg_array:
      return decodeLineSegmentArray(strValue);
    case Oid.path:
      return decodePath(strValue);
    case Oid.path_array:
      return decodePathArray(strValue);
    case Oid.point:
      return decodePoint(strValue);
    case Oid.point_array:
      return decodePointArray(strValue);
    case Oid.polygon:
      return decodePolygon(strValue);
    case Oid.polygon_array:
      return decodePolygonArray(strValue);
    case Oid.tid:
      return decodeTid(strValue);
    case Oid.tid_array:
      return decodeTidArray(strValue);
    case Oid.timestamp:
    case Oid.timestamptz:
      return decodeDatetime(strValue);
    case Oid.timestamp_array:
    case Oid.timestamptz_array:
      return decodeDatetimeArray(strValue);
    default:
      // A separate category for not handled values
      // They might or might not be represented correctly as strings,
      // returning them to the user as raw strings allows them to parse
      // them as they see fit
      return strValue;
  }
}

export function decode(value: Uint8Array, column: Column) {
  if (column.format === Format.BINARY) {
    return decodeBinary();
  } else if (column.format === Format.TEXT) {
    return decodeText(value, column.typeOid);
  } else {
    throw new Error(`Unknown column format: ${column.format}`);
  }
}