package battle

import (
	"math/rand"
	"testing"

	"github.com/honghuang-game/server/config"
)

// testConfig 返回带默认战斗参数的静态配置，保证单元测试不依赖 Nacos
func testConfig() *config.Config {
	return config.NewStaticConfig(map[string]interface{}{
		"combat.atb.gauge_max":                100,
		"combat.atb.base_coefficient":         0.1,
		"combat.battle.max_ticks":             3000,
		"combat.battle.max_actions":           50,
		"combat.mana.max":                     100,
		"combat.mana.regen_per_tick":          0.15,
		"combat.mana.regen_per_action":        3,
		"combat.mana.small_skill_cost":        20,
		"combat.mana.big_skill_cost":          40,
		"combat.skill.normal_attack_coef":     1.0,
		"combat.skill.small_coef_max":         2.5,
		"combat.skill.big_coef_min":           2.5,
		"combat.skill.small_cd":               225,
		"combat.skill.big_cd":                 800,
		"combat.skill.small_trigger_rate":     1.25,
		"combat.skill.big_trigger_rate":       2.0,
		"combat.crit.multiplier":              1.5,
		"combat.crit.rate_cap":                0.6,
		"combat.evade.rate_cap":               0.5,
		"combat.defense.coefficient":          0.5,
		"combat.atk.coefficient":              1.0,
		"combat.magic_atk.coefficient":        1.0,
		"combat.element.advantage":            1.2,
		"combat.element.disadvantage":         0.85,
		"combat.faction.cap":                  0.15,
		"combat.cc.slow_value":                0.2,
	})
}

func makePlayer(id, name, side string, str, vit, agi, luk float64) *Fighter {
	return NewFighter(id, name, "tiger_yao", side, 1, 1, BaseStats{
		Str: str,
		Vit: vit,
		Wis: 10,
		Agi: agi,
		Spi: 10,
		Luk: luk,
	}, "neutral", "none", true)
}

// countSkillUses 统计某技能在战报中使用次数
func countSkillUses(report *BattleReport, skillID string) int {
	cnt := 0
	for _, r := range report.Rounds {
		if r.SkillID == skillID {
			cnt++
		}
	}
	return cnt
}

// countActorRounds 统计某方行动次数
func countActorRounds(report *BattleReport, side string) int {
	cnt := 0
	for _, r := range report.Rounds {
		if r.Actor == side {
			cnt++
		}
	}
	return cnt
}

// TestHighSpeedCrush 验证高速方可以碾压低速目标
func TestHighSpeedCrush(t *testing.T) {
	config.Global = testConfig()

	player := makePlayer("c-001", "铁爪传", "attacker", 50, 30, 300, 30)
	monster := makePlayer("npc-001", "幽魂", "defender", 30, 25, 80, 10)
	monster.IsPlayer = false
	monster.Side = "defender"

	eng := NewEngine(player, monster, rand.New(rand.NewSource(42)), "expedition_pve", 1)
	report := eng.Run()

	if report.Result.Winner != "attacker" {
		t.Fatalf("expected attacker win, got %s", report.Result.Winner)
	}

	pa := countActorRounds(report, "attacker")
	da := countActorRounds(report, "defender")
	if pa <= da {
		t.Fatalf("expected attacker actions > defender, got attacker=%d defender=%d", pa, da)
	}
	if report.Result.FinalHP["attacker"] <= 0 {
		t.Fatalf("expected attacker survive, final hp=%d", report.Result.FinalHP["attacker"])
	}
}

// TestLowSpeedTank 验证低速肉盾可凭 HP/防御耗死敌人
func TestLowSpeedTank(t *testing.T) {
	config.Global = testConfig()

	player := makePlayer("c-002", "石盾", "attacker", 35, 120, 80, 10)
	monster := makePlayer("npc-002", "赤焰狼妖", "defender", 45, 40, 150, 15)
	monster.IsPlayer = false
	monster.Side = "defender"

	// 给玩家一个中低速但高伤的简单技能，避免纯普攻超时
	skill := &SkillInstance{
		InstanceID:  "s-001",
		SkillID:     "heavy_blow",
		Name:        "重击",
		DamageType:  DamageTypePhysical,
		Element:     "none",
		Alignment:   "neutral",
		ScalingAttr: "str",
		BaseCoef:    2.0,
		CD:          300,
		Cost:        25,
		TriggerRate: 1.5,
		TargetType:  TargetSingle,
	}
	player.AddSkill(skill)

	eng := NewEngine(player, monster, rand.New(rand.NewSource(7)), "expedition_pve", 1)
	report := eng.Run()

	if report.Result.Winner != "attacker" {
		t.Fatalf("expected attacker win, got %s", report.Result.Winner)
	}
	if report.Result.FinalHP["attacker"] <= 0 {
		t.Fatalf("expected tank survive, final hp=%d", report.Result.FinalHP["attacker"])
	}
}

// TestSkillCDConstraint 验证技能受 CD 与内力双重约束，不能无限连发
func TestSkillCDConstraint(t *testing.T) {
	config.Global = testConfig()

	player := makePlayer("c-003", "剑修", "attacker", 60, 30, 150, 20)
	monster := makePlayer("npc-003", "山魈", "defender", 30, 40, 60, 10)
	monster.IsPlayer = false
	monster.Side = "defender"

	// 高伤大招，CD 225，消耗 40
	bigSkill := &SkillInstance{
		InstanceID:  "s-002",
		SkillID:     "sky_sword",
		Name:        "天剑斩",
		DamageType:  DamageTypePhysical,
		Element:     "none",
		Alignment:   "neutral",
		ScalingAttr: "str",
		BaseCoef:    3.0,
		CD:          225,
		Cost:        40,
		TriggerRate: 2.0,
		TargetType:  TargetSingle,
	}
	player.AddSkill(bigSkill)

	eng := NewEngine(player, monster, rand.New(rand.NewSource(13)), "expedition_pve", 1)
	report := eng.Run()

	uses := countSkillUses(report, "sky_sword")
	if uses == 0 {
		t.Fatalf("expected big skill used at least once")
	}

	// 总 tick 数应远小于上限，理论上最多使用次数受 CD+回蓝限制
	// 放宽判断：使用次数不超过 15，且大招不会连续出现
	if uses > 15 {
		t.Fatalf("expected skill uses <= 15 due to CD/mana, got %d", uses)
	}

	lastTick := -9999
	for _, r := range report.Rounds {
		if r.SkillID == "sky_sword" {
			if r.Tick-lastTick < 225 {
				t.Fatalf("skill reused too soon: last=%d current=%d", lastTick, r.Tick)
			}
			lastTick = r.Tick
		}
	}
}