package world

import (
	"fmt"
	"math/rand"
	"os"
	"path/filepath"
	"strings"
	"sync"

	"thehouseoficarus/internal/action"
	"thehouseoficarus/internal/object"
	"gopkg.in/yaml.v3"
)

type MobDropTable struct {
	Remains string             `yaml:"remains"`
	Loot    []action.DropEntry `yaml:"loot"`
}

type MobDef struct {
	ID                 string    `yaml:"id"`
	Name               string    `yaml:"name"`
	Description        string    `yaml:"description"`
	IdleDescriptions   []string  `yaml:"idle_descriptions"`
	CombatDescriptions []string  `yaml:"combat_descriptions"`
	Attack             int       `yaml:"attack"`
	Strength           int       `yaml:"strength"`
	Defense            int       `yaml:"defense"`
	HP                 int       `yaml:"hp"`
	Ranged             int       `yaml:"ranged"`
	Science            int       `yaml:"science"`
	Speed              float64   `yaml:"speed"`
	Aggressive         bool      `yaml:"aggressive"`
	Protected          bool      `yaml:"protected"`
	Unique             bool      `yaml:"unique"`
	RespawnTicks       float64   `yaml:"respawn_ticks"`
	Drops              MobDropTable `yaml:"drops"`

	AttackBonus    int    `yaml:"attack_bonus"`
	StrengthBonus  int    `yaml:"strength_bonus"`
	AttackType     string `yaml:"attack_type"`

	StabDefense    int `yaml:"stab_defense"`
	SlashDefense   int `yaml:"slash_defense"`
	CrushDefense   int `yaml:"crush_defense"`
	ScienceDefense int `yaml:"science_defense"`
	RangedDefense  int `yaml:"ranged_defense"`

	Weakness    string  `yaml:"weakness"`
	StealTable  string  `yaml:"steal_table"`
	StealLevel  int     `yaml:"steal_level"`
	StealXP     int     `yaml:"steal_xp"`
	StealSpeed  float64 `yaml:"steal_speed"`

	AssassinLevel int    `yaml:"assassin_level"`
	FinishingBlow string `yaml:"finishing_blow"`
	DamageWithout string `yaml:"damage_without"`
	Size          string `yaml:"size"`

	// Kind discriminates a normal combat mob ("" or "combat") from a "task"
	// worksite (build a solar panel, survey a rock, etc.). A task mob reuses the
	// entire combat engine but its HP drains to 0 to COMPLETE the work; it never
	// attacks back (the room hazard, if any, supplies the danger). The progress
	// bar is displayed inverted (filling toward 100%).
	Kind            string `yaml:"kind"`
	Verb            string `yaml:"verb"`             // flavor verb for messages (default "work")
	ProgressNoun    string `yaml:"progress_noun"`    // flavor noun, e.g. "construction"
	CompleteMessage string `yaml:"complete_message"` // shown on completion

	Talk *action.TalkConfig `yaml:"talk,omitempty"`
}

func (d *MobDef) IsTalkable() bool { return d.Talk != nil }

func (d *MobDef) IsTask() bool { return d.Kind == "task" }

type MobInstance struct {
	InstanceID        string
	DefID             string
	Name              string
	HP                int
	MaxHP             int
	Attack            int
	Strength          int
	Defense           int
	Ranged            int
	Science           int
	Speed             float64
	Aggressive        bool
	Protected         bool
	Unique            bool
	RespawnTicks      float64
	RoomID            int
	HomeRoomID        int
	Drops             MobDropTable
	IdleDescription   string
	WanderRooms       []int
	WanderInterval    float64
	WanderTickCounter int
	regenerateTick    int

	AttackBonus    int
	StrengthBonus  int
	AttackType     string

	StabDefense    int
	SlashDefense   int
	CrushDefense   int
	ScienceDefense int
	RangedDefense  int

	Weakness    string
	StealTable  string
	StealLevel  int
	StealXP     int
	StealSpeed  float64

	AssassinLevel int
	FinishingBlow string
	DamageWithout string
	Size          string

	Kind            string
	Verb            string
	ProgressNoun    string
	CompleteMessage string

	TalkConfig *action.TalkConfig
}

func (m *MobInstance) IsTalkable() bool { return m.TalkConfig != nil }

func (m *MobInstance) IsTask() bool { return m.Kind == "task" }

func NewMobInstance(def *MobDef, instanceID string, roomID int, wanderRooms []int, wanderInterval float64) *MobInstance {
	return &MobInstance{
		InstanceID:     instanceID,
		DefID:          def.ID,
		Name:           def.Name,
		HP:             def.HP,
		MaxHP:          def.HP,
		Attack:         def.Attack,
		Strength:       def.Strength,
		Defense:        def.Defense,
		Ranged:         def.Ranged,
		Science:        def.Science,
		Speed:          def.Speed,
		Aggressive:     def.Aggressive,
		Protected:      def.Protected,
		Unique:         def.Unique,
		RespawnTicks:   def.RespawnTicks,
		RoomID:         roomID,
		HomeRoomID:     roomID,
		WanderRooms:    wanderRooms,
		WanderInterval: wanderInterval,
		Drops:          def.Drops,
		AttackBonus:    def.AttackBonus,
		StrengthBonus:  def.StrengthBonus,
		AttackType:     def.AttackType,
		StabDefense:    def.StabDefense,
		SlashDefense:   def.SlashDefense,
		CrushDefense:   def.CrushDefense,
		ScienceDefense: def.ScienceDefense,
		RangedDefense:  def.RangedDefense,
		Weakness:       def.Weakness,
		StealTable:     def.StealTable,
		StealLevel:     def.StealLevel,
		StealXP:        def.StealXP,
		StealSpeed:     def.StealSpeed,
		AssassinLevel:  def.AssassinLevel,
		FinishingBlow:  def.FinishingBlow,
		DamageWithout:  def.DamageWithout,
		Size:           def.Size,
		Kind:           def.Kind,
		Verb:           def.Verb,
		ProgressNoun:   def.ProgressNoun,
		CompleteMessage: def.CompleteMessage,
		TalkConfig:     def.Talk,
	}
}

const (
	MatchNone   = 0
	MatchPrefix = 1
	MatchExact  = 2
)

func (m *MobInstance) MatchQuality(input string) int {
	lower := strings.ToLower(input)
	if strings.ToLower(m.Name) == lower {
		return MatchExact
	}
	if object.WordPrefixMatch(input, m.Name) {
		return MatchPrefix
	}
	return MatchNone
}

func pickIdleDescription(descriptions []string) string {
	if len(descriptions) == 0 {
		return ""
	}
	return descriptions[rand.Intn(len(descriptions))]
}

func (m *MobInstance) StartRegen() {
	if m.regenerateTick == 0 {
		m.regenerateTick = 100
	}
}

type MobStore struct {
	dataDir   string
	mu        sync.Mutex
	pathIndex map[string]string
	defs      map[string]*MobDef
	instances map[string]*MobInstance
}

func NewMobStore(dataDir string) *MobStore {
	return &MobStore{
		dataDir:   dataDir,
		pathIndex: action.BuildPathIndex(filepath.Join(dataDir, "mobs")),
		defs:      make(map[string]*MobDef),
		instances: make(map[string]*MobInstance),
	}
}

func (s *MobStore) LoadDef(id string) (*MobDef, error) {
	s.mu.Lock()
	if def, ok := s.defs[id]; ok {
		s.mu.Unlock()
		return def, nil
	}
	s.mu.Unlock()

	path, ok := s.pathIndex[id]
	if !ok {
		return nil, fmt.Errorf("read mob %s: no such mob", id)
	}
	data, err := os.ReadFile(path)
	if err != nil {
		return nil, fmt.Errorf("read mob %s: %w", id, err)
	}
	var def MobDef
	if err := yaml.Unmarshal(data, &def); err != nil {
		return nil, fmt.Errorf("parse mob %s: %w", id, err)
	}

	s.mu.Lock()
	s.defs[id] = &def
	s.mu.Unlock()
	return &def, nil
}

func (s *MobStore) AllDefIDs() map[string]bool {
	ids := make(map[string]bool)
	for id := range s.pathIndex {
		ids[id] = true
	}
	return ids
}

func (s *MobStore) GetInstance(id string) *MobInstance {
	s.mu.Lock()
	defer s.mu.Unlock()
	return s.instances[id]
}

func (s *MobStore) AllInstances() []*MobInstance {
	s.mu.Lock()
	defer s.mu.Unlock()
	var out []*MobInstance
	for _, inst := range s.instances {
		out = append(out, inst)
	}
	return out
}

func (s *MobStore) MobsInRoom(roomID int) []*MobInstance {
	s.mu.Lock()
	defer s.mu.Unlock()
	var out []*MobInstance
	for _, inst := range s.instances {
		if inst.RoomID == roomID && inst.HP > 0 {
			out = append(out, inst)
		}
	}
	return out
}

func (s *MobStore) Tick() {
	s.mu.Lock()
	defer s.mu.Unlock()

	for _, inst := range s.instances {
		if inst.HP <= 0 || inst.HP >= inst.MaxHP {
			inst.regenerateTick = 0
			continue
		}
		inst.regenerateTick--
		if inst.regenerateTick <= 0 {
			inst.HP++
			if inst.HP >= inst.MaxHP {
				inst.HP = inst.MaxHP
				inst.regenerateTick = 0
			} else {
				inst.regenerateTick = 100
			}
		}
	}
}

func (s *MobStore) RollIdleDescription(inst *MobInstance) {
	def, err := s.LoadDef(inst.DefID)
	if err != nil {
		return
	}
	inst.IdleDescription = pickIdleDescription(def.IdleDescriptions)
	inst.WanderTickCounter = 0
}

func (s *MobStore) SeedMobs(roomID int, entries []RoomMob) {
	type defWrapper struct {
		def *MobDef
		err error
		rm  RoomMob
	}
	defs := make([]defWrapper, len(entries))
	for i, rm := range entries {
		d, err := s.LoadDef(rm.ID)
		defs[i] = defWrapper{d, err, rm}
	}

	s.mu.Lock()
	defer s.mu.Unlock()
	for i, dw := range defs {
		if dw.err != nil {
			continue
		}
		defID := dw.rm.ID
		instID := fmt.Sprintf("%s_%d_%d", defID, roomID, i)
		if _, exists := s.instances[instID]; exists {
			continue
		}
		inst := NewMobInstance(dw.def, instID, roomID, dw.rm.WanderRooms, dw.rm.WanderInterval)
		inst.IdleDescription = pickIdleDescription(dw.def.IdleDescriptions)
		s.instances[instID] = inst
	}
}