import BN from 'bn.js';
import { array, struct, u16, u64, u8 } from '@coral-xyz/borsh';

import { Fraction, FractionLayout } from './fraction';
import { HUNDRED_PERCENT_BPS, USDC_DECIMALS, WSOL_DECIMALS } from '../constants';

export const MAX_ORACLES_PER_TOKEN = 4;
export const MAX_ACCOUNTS_PER_ORACLE = 4;

export type FormattedOracleType = "pyth" | "raydium_clmm" | "raydium_cpmm" | "switchboard" | "example";
export const ORACLE_TYPES_STRINGS: Map<number, FormattedOracleType> = new Map([
    [0, "pyth"],
    [1, "raydium_clmm"],
    [2, "raydium_cpmm"],
    [3, "switchboard"],
    [255, "example"],
]);

export interface OraclePriceOnChain {
    price: Fraction;
    conf: Fraction;
    updateTime: BN; // u64
};

export const OraclePriceLayout = struct<OraclePriceOnChain>([
    FractionLayout.replicate('price'),
    FractionLayout.replicate('conf'),
    u64('updateTime'),
]);


export enum OracleType {
    Pyth = 0,
    RaydiumClmm = 1,
    RaydiumCpmm = 2,
    SwitchBoard = 3,
    Example = 4,
};

export enum Quote {
    Usdc = 0,
    Wsol = 1,
};

export enum Side {
    Base = 0,
    Quote = 1,
};

export interface OracleSettings {
    // type of the oracle (Pyth, CP swap, ...)
    oracleType: OracleType; // u8
    numRequiredAccounts: number; // u8
    // weight used in aggregation
    weight: number; // u16
    // whether oracle is required for aggregation
    isRequired: number; // u8
    // threshold for confidence ratio (conf / price < threshold)
    confThreshBps: number; // u16
    // how much internal price derivations can differ (≥ 1.0)
    volatilityThreshBps: number; // u16
    // max slippage allowed for min liquidity
    maxSlippageBps: number; // u16
    // minimum liquidity (in quote tokens) for valid price
    minLiquidity: BN; //u64
    // how old a price can be before it's invalid
    stalenessThresh: BN; // u64
    // rate (bps) that inflates confidence with time staleness
    stalenessConfRateBps: number; // u16
    tokenDecimals: number; // u8
    // Special parameters specific to Raydium 
    twapSecondsAgo: BN; // u64, primary twap window in seconds
    twapSecondarySecondsAgo: BN; // u64, secondary twap window - to check volatility
    quote: Quote; // u8, 1 = USDC, 2 = WSOL
    side: Side; // 0 = base, 1 = quote
}

export const OracleSettingsLayout = struct<OracleSettings>([
    u8('oracleType'),
    u8('numRequiredAccounts'),
    u16('weight'),
    u8('isRequired'),
    u16('confThreshBps'),
    u16('volatilityThreshBps'),
    u16('maxSlippageBps'),
    u64('minLiquidity'),
    u64('stalenessThresh'),
    u16('stalenessConfRateBps'),
    u8('tokenDecimals'),
    u64('twapSecondsAgo'),
    u64('twapSecondarySecondsAgo'),
    u8('quote'),
    u8('side'),
]);

export interface OracleData {
    oracleSettings: OracleSettings;
    accountsToLoadLutIds: number[]; // length MAX_ACCOUNTS_PER_ORACLE
    accountsToLoadLutIndices: number[]; // length MAX_ACCOUNTS_PER_ORACLE
};

export const OracleDataLayout = struct<OracleData>([
    OracleSettingsLayout.replicate('oracleSettings'),
    array(u8(), MAX_ACCOUNTS_PER_ORACLE, 'accountsToLoadLutIds'),
    array(u8(), MAX_ACCOUNTS_PER_ORACLE, 'accountsToLoadLutIndices'),
]);

export interface OracleAggregator {
    numOracles: number; // u8
    // minimum number of oracle results required for valid price
    minOraclesThresh: number; // u8
    oracles: OracleData[]; // [OracleData; MAX_ORACLES_PER_TOKEN]
    // minimum confidence ratio allowed (conf / price)
    minConfBps: number; // u16
    // maximum confidence ratio allowed (conf / price)
    confThreshBps: number; // u16
    // factor to expand confidence bands (≥ 1.0)
    confMultiplier: Fraction;
}

export const OracleAggregatorLayout = struct<OracleAggregator>([
    u8('numOracles'),
    u8('minOraclesThresh'),
    array(OracleDataLayout, MAX_ORACLES_PER_TOKEN, 'oracles'),
    u16('minConfBps'),
    u16('confThreshBps'),
    FractionLayout.replicate('confMultiplier')
]);


export const DEFAULT_ORACLE_SETTINGS: OracleSettings = {
    oracleType: OracleType.Pyth,
    numRequiredAccounts: 1,
    weight: HUNDRED_PERCENT_BPS,
    isRequired: 1,
    confThreshBps: 100, // TODO: 1% ??
    volatilityThreshBps: 50000,
    maxSlippageBps: 1000,
    minLiquidity: new BN(0),
    stalenessThresh: new BN(120),
    stalenessConfRateBps: 50,
    tokenDecimals: WSOL_DECIMALS,
    twapSecondsAgo:new BN(0),
    twapSecondarySecondsAgo: new BN(0),
    quote: Quote.Wsol,
    side: Side.Base,
};

export const PYTH_WSOL_ORACLE_SETTINGS: OracleSettings = {
    ...DEFAULT_ORACLE_SETTINGS,
    tokenDecimals: WSOL_DECIMALS,
}

export const PYTH_USDC_ORACLE_SETTINGS: OracleSettings = {
    ...DEFAULT_ORACLE_SETTINGS,
    tokenDecimals: USDC_DECIMALS,
}