package ai

import (
	"testing"

	"nl-game-api-gin/internal/gamecore/ddz"
)

// card 按点数造一张牌（花色取 0-3 循环，保证同点数多张时编码不同）
// 点数 r：3-15（15=2），16=小王，17=大王
func card(r, i int) int {
	if r == 16 {
		return 52
	}
	if r == 17 {
		return 53
	}
	return (r-3)*4 + i
}

// TestFarmerNotBeatPartner 平民不压队友：队友出的中等牌（J 以上）应选择过牌
func TestFarmerNotBeatPartner(t *testing.T) {
	a := &ruleDdzAI{difficulty: DiffMedium, name: "测试"}
	// 手牌里有 2（能压 J）但队友出的 J 不该压
	hand := []int{card(15, 0), card(10, 0), card(5, 0), card(5, 1)}
	last := ddz.Parse([]int{card(11, 0)}) // 队友出单张 J
	pick, _ := a.DecidePlay(hand, last, PlayContext{
		IsLandlord: false, LastIsPartner: true,
		PartnerCards: 8, LandlordCards: 10, OppMin: 10,
	})
	if pick != nil {
		t.Fatalf("平民不应压队友的大牌，却出了 %v", pick)
	}
}

// TestFarmerBeatPartnerSmall 队友前期小牌可以用小牌接管，但不能动 2/王/炸弹
func TestFarmerBeatPartnerSmall(t *testing.T) {
	a := &ruleDdzAI{difficulty: DiffMedium, name: "测试"}
	hand := []int{card(15, 0), card(8, 0), card(6, 0), card(6, 1)}
	last := ddz.Parse([]int{card(4, 0)}) // 队友出单张 4（早期小牌）
	pick, _ := a.DecidePlay(hand, last, PlayContext{
		IsLandlord: false, LastIsPartner: true,
		PartnerCards: 10, LandlordCards: 12, OppMin: 12,
	})
	if pick == nil {
		t.Fatal("队友的小牌应该用小牌接管节奏")
	}
	if c := ddz.Parse(pick); c.MainRank > 12 {
		t.Fatalf("接队友的牌不应动大牌，却出了主点数 %d", c.MainRank)
	}
}

// TestFarmerFinishOverridesCoop 能一手出完时即使是队友的牌也直接出完取胜
func TestFarmerFinishOverridesCoop(t *testing.T) {
	a := &ruleDdzAI{difficulty: DiffMedium, name: "测试"}
	hand := []int{card(14, 0)}            // 只剩一张 A
	last := ddz.Parse([]int{card(11, 0)}) // 队友出单张 J
	pick, _ := a.DecidePlay(hand, last, PlayContext{
		IsLandlord: false, LastIsPartner: true,
		PartnerCards: 3, LandlordCards: 9, OppMin: 9,
	})
	if len(pick) != 1 {
		t.Fatalf("能直接出完应立即取胜，实际出牌 %v", pick)
	}
}

// TestFarmerFeedsPartnerSingle 队友只剩 1 张时，平民自由出牌应喂最小单张
func TestFarmerFeedsPartnerSingle(t *testing.T) {
	a := &ruleDdzAI{difficulty: DiffMedium, name: "测试"}
	hand := []int{card(15, 0), card(12, 0), card(12, 1), card(3, 0)}
	pick, _ := a.DecidePlay(hand, nil, PlayContext{
		IsLandlord: false, LastIsPartner: false,
		PartnerCards: 1, LandlordCards: 8, OppMin: 8,
	})
	c := ddz.Parse(pick)
	if c == nil || c.Type != ddz.ComboSingle {
		t.Fatalf("队友剩 1 张应喂单张，实际 %v", pick)
	}
	if c.MainRank != 3 {
		t.Fatalf("应喂最小单张 3，实际主点数 %d", c.MainRank)
	}
}

// TestFarmerFeedsPartnerPair 队友只剩 2 张时优先喂最小对子
func TestFarmerFeedsPartnerPair(t *testing.T) {
	a := &ruleDdzAI{difficulty: DiffMedium, name: "测试"}
	hand := []int{card(15, 0), card(9, 0), card(9, 1), card(4, 0), card(4, 1)}
	pick, _ := a.DecidePlay(hand, nil, PlayContext{
		IsLandlord: false, LastIsPartner: false,
		PartnerCards: 2, LandlordCards: 8, OppMin: 8,
	})
	c := ddz.Parse(pick)
	if c == nil || c.Type != ddz.ComboPair {
		t.Fatalf("队友剩 2 张应喂对子，实际 %v", pick)
	}
	if c.MainRank != 4 {
		t.Fatalf("应喂最小对子 4，实际主点数 %d", c.MainRank)
	}
}

// TestFarmerBlocksLandlordEndgame 地主只剩 1 张时，平民领出应避免送小单牌
func TestFarmerBlocksLandlordEndgame(t *testing.T) {
	a := &ruleDdzAI{difficulty: DiffMedium, name: "测试"}
	// 手牌：小单 3、对 7、大单 A
	hand := []int{card(14, 0), card(7, 0), card(7, 1), card(3, 0)}
	pick, _ := a.DecidePlay(hand, nil, PlayContext{
		IsLandlord: false, LastIsPartner: false,
		PartnerCards: 10, LandlordCards: 1, OppMin: 1,
	})
	c := ddz.Parse(pick)
	if c == nil {
		t.Fatal("应有出牌")
	}
	// 不应送出最小单张 3（地主最后一张很可能压过）
	if c.Type == ddz.ComboSingle && c.MainRank == 3 {
		t.Fatal("地主只剩 1 张时不应送最小单牌")
	}
}

// TestLandlordUnchanged 地主视角：正常出能压住的最小牌，不受配合逻辑影响
func TestLandlordUnchanged(t *testing.T) {
	a := &ruleDdzAI{difficulty: DiffMedium, name: "测试"}
	hand := []int{card(15, 0), card(10, 0), card(6, 0)}
	last := ddz.Parse([]int{card(5, 0)})
	pick, _ := a.DecidePlay(hand, last, PlayContext{
		IsLandlord: true, LandlordCards: 3, OppMin: 10,
	})
	c := ddz.Parse(pick)
	if c == nil || c.MainRank != 6 {
		t.Fatalf("地主应出能压住的最小牌 6，实际 %v", pick)
	}
}