feat: investment accounts

internal/model/investment.go

@@ -0,0 +1,83 @@
+package model
+
+import (
+	"time"
+
+	"github.com/shopspring/decimal"
+)
+
+type InvestmentContributionRoom struct {
+	AccountID  string          `db:"account_id"`
+	Year       int             `db:"year"`
+	RoomAmount decimal.Decimal `db:"room_amount"`
+	CreatedAt  time.Time       `db:"created_at"`
+	UpdatedAt  time.Time       `db:"updated_at"`
+}
+
+type InvestmentHolding struct {
+	ID          string    `db:"id"`
+	AccountID   string    `db:"account_id"`
+	Symbol      string    `db:"symbol"`
+	DisplayName string    `db:"display_name"`
+	CreatedAt   time.Time `db:"created_at"`
+	UpdatedAt   time.Time `db:"updated_at"`
+}
+
+type InvestmentTradeType string
+
+const (
+	InvestmentTradeTypeBuy  InvestmentTradeType = "buy"
+	InvestmentTradeTypeSell InvestmentTradeType = "sell"
+)
+
+func IsValidInvestmentTradeType(t string) bool {
+	switch InvestmentTradeType(t) {
+	case InvestmentTradeTypeBuy, InvestmentTradeTypeSell:
+		return true
+	}
+	return false
+}
+
+type InvestmentTrade struct {
+	ID           string              `db:"id"`
+	HoldingID    string              `db:"holding_id"`
+	Type         InvestmentTradeType `db:"type"`
+	Quantity     decimal.Decimal     `db:"quantity"`
+	PricePerUnit decimal.Decimal     `db:"price_per_unit"`
+	Fees         *decimal.Decimal    `db:"fees"`
+	OccurredAt   time.Time           `db:"occurred_at"`
+	Notes        *string             `db:"notes"`
+	CreatedAt    time.Time           `db:"created_at"`
+}
+
+// HoldingPosition aggregates a holding with its derived figures across all
+// trades. Quantity is the net of buys minus sells. AvgCost is the weighted
+// average per-unit cost of remaining shares (reduced proportionally on sells).
+// RealizedPL is the cumulative realized profit/loss from sells.
+type HoldingPosition struct {
+	Holding        InvestmentHolding
+	Quantity       decimal.Decimal
+	AvgCost        decimal.Decimal
+	CostBasis      decimal.Decimal
+	LastBuyPrice   *decimal.Decimal
+	LastSellPrice  *decimal.Decimal
+	RealizedPL     decimal.Decimal
+	TotalBuyQty    decimal.Decimal
+	TotalSellQty   decimal.Decimal
+	TotalFees      decimal.Decimal
+}
+
+// InvestmentAccountSummary is the rolled-up view for an investment-flagged
+// account: contribution room and YTD cash flow plus aggregate cost basis across
+// holdings.
+type InvestmentAccountSummary struct {
+	Account            *Account
+	Year               int
+	RoomAmount         *decimal.Decimal // nil if room not yet set for the year
+	YTDContributions   decimal.Decimal
+	YTDWithdrawals     decimal.Decimal
+	RoomRemaining      *decimal.Decimal // nil if RoomAmount is nil
+	NetContributions   decimal.Decimal  // lifetime: all deposits minus all withdrawals
+	TotalCostBasis     decimal.Decimal
+	HoldingCount       int
+}