package ai

import (
	"encoding/json"
	"testing"

	"github.com/greyson/super-auto-pets-board-game/internal/game"
)

// A debug report is only worth taking if replaying it reproduces the battle it
// captured, and the situations worth reporting are the messy ones — six seats,
// three packs shuffled together, Mana and Trumpets banked, Komodo shuffling
// apples into a deck mid-fight. This test lives in the ai package because that
// is where full games get played: it hands the bots a table, then replays every
// battle of the last round out of the report and demands the identical result.
//
// If it ever fails, the engine has grown a source of randomness (or a piece of
// battle input) that the result doesn't record, and reports of that battle are
// no longer reproducible.
func TestDebugReportReplaysRealGames(t *testing.T) {
	for _, tc := range []struct {
		name   string
		packs  []string
		levels []float64
	}{
		{"two seats, one pack", []string{"turtle"}, []float64{0.9, 0.9}},
		{"six seats, three packs", []string{"turtle", "golden", "unicorn"},
			[]float64{0.9, 0.9, 0.9, 0.9, 0.9, 0.9}},
	} {
		t.Run(tc.name, func(t *testing.T) {
			g := playBotTable(t, tc.packs, tc.levels...)
			rep, err := g.DebugReport()
			if err != nil {
				t.Fatal(err)
			}
			if len(g.Battles) == 0 {
				t.Fatal("a finished game should have battles to replay")
			}
			for i, recorded := range g.Battles {
				replayed, err := rep.ReplayBattle(i)
				if err != nil {
					t.Fatalf("battle %d: %v", i, err)
				}
				if got, want := marshal(t, replayed), marshal(t, recorded); got != want {
					t.Fatalf("battle %d replayed differently:\nrecorded %s\nreplayed %s", i, want, got)
				}
			}
		})
	}
}

func marshal(t *testing.T, res *game.BattleResult) string {
	t.Helper()
	b, err := json.Marshal(res)
	if err != nil {
		t.Fatal(err)
	}
	return string(b)
}