package crypto

import (
	"context"
	"encoding/json"

	decimal "github.com/alpacahq/alpacadecimal"
	"s1d3sw1ped/robinhood-agentic-mcp/client"
	"s1d3sw1ped/robinhood-agentic-mcp/internal/wire"
)

const (
	toolPairs     = "get_currency_pairs"
	toolQuotes    = "get_crypto_quotes"
	toolPositions = "get_crypto_positions"
	toolOrders    = "get_crypto_orders"
	toolPreview   = "preview_crypto_order"
	toolPlace     = "place_crypto_order"
	toolCancel    = "cancel_crypto_order"
)

// PairsRequest is the argument set for get_currency_pairs.
type PairsRequest struct {
	Cursor string
	Limit  int
}

// CurrencyPair is one row from get_currency_pairs.
type CurrencyPair struct {
	ID     string
	Symbol string
}

// PairsResult is the parsed get_currency_pairs payload.
type PairsResult struct {
	Pairs      []CurrencyPair
	NextCursor string
}

// QuotesRequest is the argument set for get_crypto_quotes.
type QuotesRequest struct {
	Symbols          []string
	Timezone         string
	RHSAccountNumber string
}

// CryptoQuote is one pair quote from get_crypto_quotes.
type CryptoQuote struct {
	Symbol    string
	Bid       decimal.Decimal
	Ask       decimal.Decimal
	Mark      decimal.Decimal
	PrevClose decimal.Decimal
}

// QuotesResult is the parsed get_crypto_quotes payload.
type QuotesResult struct {
	Quotes []CryptoQuote
}

// PositionsRequest is the argument set for get_crypto_positions.
type PositionsRequest struct {
	RHSAccountNumber string
	Cursor           string
}

// CryptoPosition is one holding from get_crypto_positions.
type CryptoPosition struct {
	Symbol    string
	Quantity  decimal.Decimal
	CostBasis decimal.Decimal
}

// PositionsResult is the parsed get_crypto_positions payload.
type PositionsResult struct {
	Positions  []CryptoPosition
	NextCursor string
}

// OrdersRequest is the argument set for get_crypto_orders.
type OrdersRequest struct {
	RHSAccountNumber string
	OrderID          string
	State            string
	StateGroup       string
	Side             client.Side
	Symbol           string
	CreatedAtGTE     string
	UpdatedAtGTE     string
	Cursor           string
}

// OrdersResult is the parsed get_crypto_orders payload.
type OrdersResult struct {
	Orders     []Order
	NextCursor string
}

// PlaceOrderRequest is the argument set for preview_crypto_order and place_crypto_order.
type PlaceOrderRequest struct {
	RHSAccountNumber string
	Symbol           string
	Side             client.Side
	Type             client.OrderType
	Qty              *decimal.Decimal
	DollarAmount     *decimal.Decimal
	LimitPrice       *decimal.Decimal
	StopPrice        *decimal.Decimal
	TimeInForce      client.TimeInForce // empty → omit (Robinhood defaults gtc/gfd by type)
	RefID            string
}

// PreviewResult is the pre-trade check from preview_crypto_order.
type PreviewResult struct {
	Errors   []string        `json:"errors"`
	Warnings []string        `json:"warnings"`
	Quantity decimal.Decimal `json:"-"`
	Price    decimal.Decimal `json:"-"`
}

// Order is a placed or listed crypto order.
type Order struct {
	ID     string          `json:"id"`
	Symbol string          `json:"symbol"`
	Side   string          `json:"side"`
	State  string          `json:"state"`
	Qty    decimal.Decimal `json:"-"`
}

// CancelOrderRequest is the argument set for cancel_crypto_order.
type CancelOrderRequest struct {
	RHSAccountNumber string
	OrderID          string
}

// Pairs calls get_currency_pairs.
func (c *Client) Pairs(ctx context.Context, req PairsRequest) (PairsResult, error) {
	args := map[string]any{}
	if req.Cursor != "" {
		args["cursor"] = req.Cursor
	}
	if req.Limit != 0 {
		args["limit"] = req.Limit
	}
	var out PairsResult
	if err := c.parse(ctx, toolPairs, args, &out); err != nil {
		return PairsResult{}, err
	}
	return out, nil
}

// Quotes calls get_crypto_quotes.
func (c *Client) Quotes(ctx context.Context, req QuotesRequest) (QuotesResult, error) {
	args := map[string]any{}
	if len(req.Symbols) > 0 {
		args["symbols"] = req.Symbols
	}
	if req.Timezone != "" {
		args["timezone"] = req.Timezone
	}
	if req.RHSAccountNumber != "" {
		args["rhs_account_number"] = req.RHSAccountNumber
	}
	var out QuotesResult
	if err := c.parse(ctx, toolQuotes, args, &out); err != nil {
		return QuotesResult{}, err
	}
	return out, nil
}

// Positions calls get_crypto_positions.
func (c *Client) Positions(ctx context.Context, req PositionsRequest) (PositionsResult, error) {
	args := map[string]any{}
	if req.RHSAccountNumber != "" {
		args["rhs_account_number"] = req.RHSAccountNumber
	}
	if req.Cursor != "" {
		args["cursor"] = req.Cursor
	}
	var out PositionsResult
	if err := c.parse(ctx, toolPositions, args, &out); err != nil {
		return PositionsResult{}, err
	}
	return out, nil
}

// Orders calls get_crypto_orders.
func (c *Client) Orders(ctx context.Context, req OrdersRequest) (OrdersResult, error) {
	args := map[string]any{}
	if req.RHSAccountNumber != "" {
		args["rhs_account_number"] = req.RHSAccountNumber
	}
	if req.OrderID != "" {
		args["order_id"] = req.OrderID
	}
	if req.State != "" {
		args["state"] = req.State
	}
	if req.StateGroup != "" {
		args["state_group"] = req.StateGroup
	}
	if req.Side != "" {
		args["side"] = string(req.Side)
	}
	if req.Symbol != "" {
		args["symbol"] = req.Symbol
	}
	if req.CreatedAtGTE != "" {
		args["created_at_gte"] = req.CreatedAtGTE
	}
	if req.UpdatedAtGTE != "" {
		args["updated_at_gte"] = req.UpdatedAtGTE
	}
	if req.Cursor != "" {
		args["cursor"] = req.Cursor
	}
	var out OrdersResult
	if err := c.parse(ctx, toolOrders, args, &out); err != nil {
		return OrdersResult{}, err
	}
	return out, nil
}

// PreviewOrder calls preview_crypto_order. RefID is not sent.
func (c *Client) PreviewOrder(ctx context.Context, req PlaceOrderRequest) (PreviewResult, error) {
	var out PreviewResult
	if err := c.parse(ctx, toolPreview, placeArgs(req, false), &out); err != nil {
		return PreviewResult{}, err
	}
	return out, nil
}

// PlaceOrder calls place_crypto_order. RefID is sent as ref_id.
func (c *Client) PlaceOrder(ctx context.Context, req PlaceOrderRequest) (Order, error) {
	raw, err := c.c.Call(ctx, toolPlace, placeArgs(req, true))
	if err != nil {
		return Order{}, err
	}
	ords, err := parseOrders(raw)
	if err != nil {
		return Order{}, client.ToolErrorf(toolPlace, "parse: %w", err)
	}
	if len(ords) > 0 {
		return ords[0], nil
	}
	return Order{}, nil
}

// CancelOrder calls cancel_crypto_order.
func (c *Client) CancelOrder(ctx context.Context, req CancelOrderRequest) error {
	args := map[string]any{}
	if req.RHSAccountNumber != "" {
		args["rhs_account_number"] = req.RHSAccountNumber
	}
	if req.OrderID != "" {
		args["order_id"] = req.OrderID
	}
	_, err := c.c.Call(ctx, toolCancel, args)
	return err
}

func placeArgs(req PlaceOrderRequest, withRef bool) map[string]any {
	args := map[string]any{}
	if req.RHSAccountNumber != "" {
		args["rhs_account_number"] = req.RHSAccountNumber
	}
	if req.Symbol != "" {
		args["symbol"] = req.Symbol
	}
	if req.Side != "" {
		args["side"] = string(req.Side)
	}
	if req.Type != "" {
		args["type"] = string(req.Type)
	}
	if req.Qty != nil {
		args["quantity"] = wire.Encode(*req.Qty)
	}
	if req.DollarAmount != nil {
		args["dollar_amount"] = wire.Encode(*req.DollarAmount)
	}
	if req.LimitPrice != nil {
		args["limit_price"] = wire.Encode(*req.LimitPrice)
	}
	if req.StopPrice != nil {
		args["stop_price"] = wire.Encode(*req.StopPrice)
	}
	if req.TimeInForce != "" {
		args["time_in_force"] = string(req.TimeInForce)
	}
	if withRef && req.RefID != "" {
		args["ref_id"] = req.RefID
	}
	return args
}

func (c *Client) parse(ctx context.Context, tool string, args map[string]any, dest any) error {
	raw, err := c.c.Call(ctx, tool, args)
	if err != nil {
		return err
	}
	if err := json.Unmarshal(wire.Unwrap(raw), dest); err != nil {
		return client.ToolErrorf(tool, "parse: %w", err)
	}
	return nil
}