mtgban: Guarantee to keep data arrays sorted

abugames/abugames.go

@@ -3,7 +3,6 @@ package abugames
 import (
 	"errors"
 	"net/url"
-	"sort"
 	"sync"
 	"time"
 
@@ -238,18 +237,6 @@ func (abu *ABUGames) scrape() error {
 		}
 	}
 
-	// Sort to keep NM entries first
-	for cardId := range abu.inventory {
-		sort.Slice(abu.inventory[cardId], func(i, j int) bool {
-			return abu.inventory[cardId][i].Price > abu.inventory[cardId][j].Price
-		})
-	}
-	for cardId := range abu.buylist {
-		sort.Slice(abu.buylist[cardId], func(i, j int) bool {
-			return abu.buylist[cardId][i].BuyPrice > abu.buylist[cardId][j].BuyPrice
-		})
-	}
-
 	abu.inventoryDate = time.Now()
 	abu.buylistDate = time.Now()
 

cardtrader/cardtrader.go

@@ -4,7 +4,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"sort"
 	"sync"
 	"time"
 
@@ -294,14 +293,6 @@ func (ct *CardtraderMarket) scrape() error {
 		}
 	}
 
-	// Sort to keep NM-SP-MP-HP-PO order
-	conds := map[string]int{"NM": 0, "SP": 1, "MP": 2, "HP": 3, "PO": 4}
-	for cardId := range ct.inventory {
-		sort.Slice(ct.inventory[cardId], func(i, j int) bool {
-			return conds[ct.inventory[cardId][i].Conditions] < conds[ct.inventory[cardId][j].Conditions]
-		})
-	}
-
 	ct.inventoryDate = time.Now()
 
 	return nil

mtgban/base.go

@@ -2,9 +2,11 @@ package mtgban
 
 import (
 	"fmt"
+	"sort"
 
 	"github.com/google/uuid"
 	"github.com/mtgban/go-mtgban/mtgmatcher"
+	"golang.org/x/exp/slices"
 )
 
 func computeSKU(cardId, condition string) (string, error) {
@@ -60,6 +62,24 @@ func (inv InventoryRecord) add(cardId string, entry *InventoryEntry, strict int)
 	}
 
 	inv[cardId] = append(inv[cardId], *entry)
+
+	// Keep array sorted
+	sort.Slice(inv[cardId], func(i, j int) bool {
+		iIdx := slices.Index(FullGradeTags, inv[cardId][i].Conditions)
+		jIdx := slices.Index(FullGradeTags, inv[cardId][j].Conditions)
+
+		if iIdx == jIdx {
+			if inv[cardId][i].Price == inv[cardId][j].Price {
+				// Prioritize higher quantity for same price and same condition
+				return inv[cardId][i].Quantity > inv[cardId][j].Quantity
+			}
+			// Prioritize lower prices first for the same condition
+			return inv[cardId][i].Price < inv[cardId][j].Price
+		}
+
+		return iIdx < jIdx
+	})
+
 	return nil
 }
 
@@ -110,6 +130,22 @@ func (bl BuylistRecord) add(cardId string, entry *BuylistEntry, strict bool) err
 
 	bl[cardId] = append(bl[cardId], *entry)
 
+	sort.Slice(bl[cardId], func(i, j int) bool {
+		iIdx := slices.Index(FullGradeTags, bl[cardId][i].Conditions)
+		jIdx := slices.Index(FullGradeTags, bl[cardId][j].Conditions)
+
+		if iIdx == jIdx {
+			if bl[cardId][i].BuyPrice == bl[cardId][j].BuyPrice {
+				// Prioritize higher quantity for same price and same condition
+				return bl[cardId][i].Quantity > bl[cardId][j].Quantity
+			}
+			// Prioritize higher prices first for the same condition
+			return bl[cardId][i].BuyPrice > bl[cardId][j].BuyPrice
+		}
+
+		return iIdx < jIdx
+	})
+
 	return nil
 }
 

mtgban/base_test.go

@@ -1,6 +1,7 @@
 package mtgban
 
 import (
+	"math/rand"
 	"testing"
 )
 
@@ -237,3 +238,78 @@ func TestAddStrict(t *testing.T) {
 
 	t.Log("PASS: AddStrict")
 }
+
+func TestSort(t *testing.T) {
+	testEntries := []InventoryEntry{
+		{
+			Quantity:   5,
+			Conditions: "NM",
+			Price:      20.0,
+			URL:        "https://mtgban.com",
+			SellerName: "BANNED",
+		},
+		{
+			Quantity:   4,
+			Conditions: "SP",
+			Price:      8.0,
+			URL:        "https://mtgban.com",
+			SellerName: "BANNED",
+		},
+		{
+			Quantity:   4,
+			Conditions: "SP",
+			Price:      10.0,
+			URL:        "https://mtgban.com",
+			SellerName: "BANNED",
+		},
+		{
+			Quantity:   1,
+			Conditions: "SP",
+			Price:      10.0,
+			URL:        "https://mtgban.com",
+			SellerName: "BANNED_TWO",
+		},
+	}
+
+	rand.Shuffle(len(testEntries), func(i, j int) {
+		testEntries[i], testEntries[j] = testEntries[j], testEntries[i]
+	})
+
+	expectedCond := []string{"NM", "SP", "SP", "SP"}
+	expectedPrice := []float64{20.0, 8.0, 10.0, 10.0}
+	expectedQty := []int{5, 4, 4, 1}
+
+	inventory := InventoryRecord{}
+
+	// Add all the entries in wrong order
+	for _, testEntry := range testEntries {
+		err := inventory.AddStrict("A", &testEntry)
+		if err != nil {
+			t.Errorf("FAIL: Unexpected error: %s", err.Error())
+			return
+		}
+	}
+	if len(inventory["A"]) != len(testEntries) {
+		t.Errorf("FAIL: inventory contains a differen number of entries (%d) than expected (%d) for A", len(inventory["A"]), len(testEntries))
+		return
+	}
+
+	for _, entries := range inventory {
+		for i := range entries {
+			if entries[i].Conditions != expectedCond[i] {
+				t.Errorf("FAIL: array not sorted: condition of %d is not %s (got %s)", i, expectedCond[i], entries[i].Conditions)
+				return
+			}
+			if entries[i].Price != expectedPrice[i] {
+				t.Errorf("FAIL: array not sorted: price of %d is not %f (got %f)", i, expectedPrice[i], entries[i].Price)
+				return
+			}
+			if entries[i].Quantity != expectedQty[i] {
+				t.Errorf("FAIL: array not sorted: quantity of %d is not %d (got %d)", i, expectedQty[i], entries[i].Quantity)
+				return
+			}
+		}
+	}
+
+	t.Log("PASS: Sort")
+}