feat: compute proper tx prioritization (#1290)

## Description

closes: #510

---

### Author Checklist

_All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues._

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] added appropriate labels to the PR
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/umee-network/umee/blob/main/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

_All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items._

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed all author checklist items have been addressed
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

ante/fee.go

@@ -1,12 +1,12 @@
 package ante
 
 import (
-	"math"
-
 	gbtypes "github.com/Gravity-Bridge/Gravity-Bridge/module/x/gravity/types"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
+	evidencetypes "github.com/cosmos/cosmos-sdk/x/evidence/types"
 
+	leveragetypes "github.com/umee-network/umee/v3/x/leverage/types"
 	oracletypes "github.com/umee-network/umee/v3/x/oracle/types"
 )
 
@@ -50,7 +50,7 @@ func FeeAndPriority(ctx sdk.Context, tx sdk.Tx) (sdk.Coins, int64, error) {
 		}
 	}
 
-	priority := getTxPriority(feeCoins, isOracleOrGravity)
+	priority := getTxPriority(isOracleOrGravity, msgs)
 	if !chargeFees {
 		return sdk.Coins{}, priority, nil
 	}
@@ -59,6 +59,9 @@ func FeeAndPriority(ctx sdk.Context, tx sdk.Tx) (sdk.Coins, int64, error) {
 
 // IsOracleOrGravityTx checks if all messages are oracle messages
 func IsOracleOrGravityTx(msgs []sdk.Msg) bool {
+	if len(msgs) == 0 {
+		return false
+	}
 	for _, msg := range msgs {
 		switch msg.(type) {
 		case *oracletypes.MsgAggregateExchangeRatePrevote,
@@ -89,23 +92,42 @@ func IsOracleOrGravityTx(msgs []sdk.Msg) bool {
 
 // getTxPriority returns naive tx priority based on the lowest fee amount (regardless of the
 // denom) and oracle tx check.
-func getTxPriority(fee sdk.Coins, isOracleOrGravity bool) int64 {
+// Dirty optimization: since we already check if msgs are oracle or gravity messages, then we
+// don't recomupte it again: isOracleOrGravity flag takes a precedence over msgs check.
+func getTxPriority( /*fees, gasAmount*/ isOracleOrGravity bool, msgs []sdk.Msg) int64 {
 	var priority int64
-	for _, c := range fee {
-		// TODO: we should better compare amounts
-		// https://github.com/umee-network/umee/issues/510
+	/* TODO: IBC tx prioritization is not stable and we will implement a more general
+	 * tx prioritization once that will be resolved
+	 * https://github.com/umee-network/umee/issues/1289
+	for _, c := range fees {
 		p := int64(math.MaxInt64)
-		if c.Amount.IsInt64() {
-			p = c.Amount.Int64()
+		gasPrice := c.Amount.QuoRaw(gasAmount)
+		if gasPrice.IsInt64() {
+			p = gasPrice.Int64()
 		}
 		if priority == 0 || p < priority {
 			priority = p
 		}
 	}
+	*/
 	if isOracleOrGravity {
-		// TODO: this is a naive version.
-		// Proper solution will be implemented in https://github.com/umee-network/umee/issues/510
-		priority += 100000
+		return 100
 	}
+	for _, msg := range msgs {
+		var p int64
+		switch msg.(type) {
+		case *evidencetypes.MsgSubmitEvidence:
+			p = 90
+		case *leveragetypes.MsgLiquidate:
+			p = 80
+		default:
+			// in case there is a non-prioritized mixed message, we return 0
+			return 0
+		}
+		if priority == 0 || p < priority {
+			priority = p
+		}
+	}
+
 	return priority
 }

ante/fee_unit_test.go

@@ -0,0 +1,37 @@
+package ante
+
+import (
+	"testing"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	bank "github.com/cosmos/cosmos-sdk/x/bank/types"
+	evidence "github.com/cosmos/cosmos-sdk/x/evidence/types"
+	"github.com/stretchr/testify/assert"
+
+	leverage "github.com/umee-network/umee/v3/x/leverage/types"
+)
+
+func TestPriority(t *testing.T) {
+	tcs := []struct {
+		name     string
+		oracle   bool
+		msgs     []sdk.Msg
+		priority int64
+	}{
+		{"empty priority 0", false, []sdk.Msg{}, 0},
+		{"when oracleOrGravity is set, then tx is max", true, []sdk.Msg{}, 100},
+		{"evidence1", true, []sdk.Msg{&evidence.MsgSubmitEvidence{}}, 100},
+		{"evidence2", false, []sdk.Msg{&evidence.MsgSubmitEvidence{}}, 90},
+		{"evidence3", false, []sdk.Msg{&evidence.MsgSubmitEvidence{}, &evidence.MsgSubmitEvidence{}}, 90},
+		{"leverage1", false, []sdk.Msg{&leverage.MsgLiquidate{}}, 80},
+		{"leverage-evidence1", false, []sdk.Msg{&leverage.MsgLiquidate{}, &evidence.MsgSubmitEvidence{}}, 80},
+		{"leverage-evidence2", false, []sdk.Msg{&evidence.MsgSubmitEvidence{}, &leverage.MsgLiquidate{}}, 80},
+		{"mixed1", false, []sdk.Msg{&evidence.MsgSubmitEvidence{}, &leverage.MsgLiquidate{}, &bank.MsgSend{}}, 0},
+		{"mixed2", false, []sdk.Msg{&bank.MsgSend{}, &evidence.MsgSubmitEvidence{}, &leverage.MsgLiquidate{}}, 0},
+	}
+
+	for _, tc := range tcs {
+		p := getTxPriority(tc.oracle, tc.msgs)
+		assert.Equal(t, tc.priority, p, tc.name)
+	}
+}