package strategy

import (
	"github.com/shopspring/decimal"
	"testing"
)

func TestRSI_WarmupAndRange(t *testing.T) {
	n := 2
	r := NewRSI(n)

	type step struct {
		close     float64
		wantReady bool
	}
	steps := []step{
		{10, false}, // 第一根，只建立 prevC
		{11, false}, // 第二根，累積
		{12, true},  // 第三根，完成 seed -> ready
		{13, true},
		{12, true},
		{11, true},
		{12, true},
		{13, true},
	}

	for i, st := range steps {
		val, ready := r.Push(CandleForStrategy{C: dv(st.close)})
		if ready != st.wantReady {
			t.Fatalf("step %d: ready got=%v want=%v", i, ready, st.wantReady)
		}
		if ready {
			// RSI 應落在 0..100
			if val.LessThan(decimal.Zero) || val.GreaterThan(decimal.NewFromInt(100)) {
				t.Fatalf("step %d: RSI out of [0,100], got %s", i, val)
			}
		}
	}
}

func TestRSI_PerfectUpAndDown(t *testing.T) {
	n := 2
	r := NewRSI(n)

	// 先 seed
	_, _ = r.Push(CandleForStrategy{C: d(10)})
	_, _ = r.Push(CandleForStrategy{C: d(11)})
	val, ready := r.Push(CandleForStrategy{C: d(12)})
	if !ready {
		t.Fatalf("should be ready after %d candles", n)
	}

	// 連續上漲：理想情況 avgLoss -> 0，RSI 逼近 100
	val, ready = r.Push(CandleForStrategy{C: d(13)})
	if !ready || !val.LessThanOrEqual(decimal.NewFromInt(100)) {
		t.Fatalf("uptrend: ready=%v val=%s", ready, val)
	}

	// 連續下跌：理想情況 avgGain -> 0，RSI 逼近 0
	r = NewRSI(n)
	_, _ = r.Push(CandleForStrategy{C: d(13)})
	_, _ = r.Push(CandleForStrategy{C: d(12)})
	val, ready = r.Push(CandleForStrategy{C: d(11)})
	if !ready {
		t.Fatalf("should be ready after %d candles", n)
	}
	val, ready = r.Push(CandleForStrategy{C: d(10)})
	if !ready || !val.GreaterThanOrEqual(decimal.Zero) {
		t.Fatalf("downtrend: ready=%v val=%s", ready, val)
	}
}