package game

import (
	"fmt"
	"strings"

	"thehouseoficarus/internal/casino"
	"thehouseoficarus/internal/net"
	"thehouseoficarus/internal/player"
)

func (g *Game) doGet(sess *net.Session, input string) {
	p := sess.Player
	g.cancelAction(p)
	// Only stock this player may actually take counts: entries reserved
	// for another player are invisible to the pickup, so a blocked pickup
	// can never half-remove the ground stack.
	ground := g.World.AccessibleGround(p.RoomID, p.Name)
	if len(ground) == 0 {
		sess.WriteLine("There's nothing on the ground to pick up.")
		return
	}

	qty, itemName := parseQty(input)

	matches := g.findGroundMatches(itemName, p.RoomID)
	if len(matches) == 0 {
		sess.WriteLine(fmt.Sprintf("There's no '%s' here.", itemName))
		return
	}

	if len(matches) > 1 {
		unique := uniqueItemNames(matches)
		if len(unique) > 1 {
			g.showWhichOne(sess, matches)
			return
		}
	}

	itemID := matches[0].ID

	if itemID == "credits" {
		g.pickupCredits(sess, p, itemID)
		return
	}

	def, _ := g.ItemStore.Load(itemID)
	name := itemID
	if def != nil {
		name = def.Name
	}

	available := 0
	if gqty, ok := ground[itemID]; ok {
		available = gqty
	}
	if available <= 0 {
		sess.WriteLine("There's none of that here.")
		return
	}

	if qty == 0 {
		if def != nil && def.Stackable {
			qty = available
		} else {
			qty = 1
		}
	} else if qty > available {
		qty = available
	}

	// No premature free-slot gate here: a stackable pickup may merge into an
	// existing stack even when every slot is occupied, so capacity is only
	// required when a new slot is actually needed (matching doGetAll and
	// doGetAllNamed). See TestPickupMergesIntoFullInventory.

	if def != nil && def.Stackable {
		quality, maxQuality := g.pickedStackProps(itemID)
		for i := 0; i < 28; i++ {
			slot := p.InvSlot(i)
			if slot == nil || slot.ItemID != itemID || slot.Quality != quality || slot.MaxQuality != maxQuality {
				continue
			}
			removed, ok := g.World.RemoveReservedItem(p.RoomID, itemID, qty, p.Name)
			if !ok {
				sess.WriteLine("That's not yours!")
				return
			}
			slot.Quantity += removed
			g.saveCharacter(p)
			sess.WriteLine(fmt.Sprintf("You pick up %d x %s. (now %d)", qty, g.itemColorize(sess, def, def.Name), slot.Quantity))
			return
		}
		freeSlot := p.FirstFreeSlot()
		if freeSlot == -1 {
			sess.WriteLine("Your inventory is full.")
			return
		}
		if _, ok := g.World.RemoveReservedItem(p.RoomID, itemID, qty, p.Name); !ok {
			sess.WriteLine("That's not yours!")
			return
		}
		p.SetInvSlot(freeSlot, g.newInventorySlot(itemID, qty))
		g.saveCharacter(p)
		if qty == 1 {
			sess.WriteLine(fmt.Sprintf("You pick up a %s.", g.itemColorize(sess, def, def.Name)))
		} else {
			sess.WriteLine(fmt.Sprintf("You pick up %d x %s.", qty, g.itemColorize(sess, def, def.Name)))
		}
		return
	}

	picked := 0
	for picked < qty {
		fs := p.FirstFreeSlot()
		if fs == -1 {
			break
		}
		if _, ok := g.World.RemoveReservedItem(p.RoomID, itemID, 1, p.Name); !ok {
			break
		}
		p.SetInvSlot(fs, g.newInventorySlot(itemID, 1))
		picked++
	}

	g.saveCharacter(p)
	if picked == 0 {
		sess.WriteLine("Your inventory is full.")
	} else if picked == 1 {
		sess.WriteLine(fmt.Sprintf("You pick up a %s.", g.itemColorize(sess, def, name)))
	} else {
		sess.WriteLine(fmt.Sprintf("You pick up %d x %s.", picked, g.itemColorize(sess, def, name)))
	}
}

func (g *Game) doGetAllNamed(sess *net.Session, input string) {
	p := sess.Player
	g.cancelAction(p)
	// Only takeable stock counts (see doGet).
	ground := g.World.AccessibleGround(p.RoomID, p.Name)
	if len(ground) == 0 {
		sess.WriteLine("There's nothing on the ground to pick up.")
		return
	}

	matches := g.findGroundMatches(input, p.RoomID)
	if len(matches) == 0 {
		sess.WriteLine(fmt.Sprintf("There's no '%s' here.", input))
		return
	}

	if len(matches) > 1 {
		unique := uniqueItemNames(matches)
		if len(unique) > 1 {
			g.showWhichOne(sess, matches)
			return
		}
	}

	itemID := matches[0].ID

	if itemID == "credits" {
		g.pickupCredits(sess, p, itemID)
		return
	}

	def, _ := g.ItemStore.Load(itemID)

	available := 0
	if gqty, ok := ground[itemID]; ok {
		available = gqty
	}
	if available <= 0 {
		sess.WriteLine("There's none of that here.")
		return
	}

	wanted := available
	if def != nil && !def.Stackable {
		free := p.FreeSlots()
		if wanted > free {
			wanted = free
		}
	}

	if wanted <= 0 {
		sess.WriteLine("Your inventory is full.")
		return
	}

	name := itemID
	if def != nil {
		name = def.Name
	}
	coloredName := g.itemColorize(sess, def, name)

	if def != nil && def.Stackable {
		quality, maxQuality := g.pickedStackProps(itemID)
		for i := 0; i < 28; i++ {
			slot := p.InvSlot(i)
			if slot == nil || slot.ItemID != itemID || slot.Quality != quality || slot.MaxQuality != maxQuality {
				continue
			}
			removed, ok := g.World.RemoveReservedItem(p.RoomID, itemID, wanted, p.Name)
			if !ok {
				sess.WriteLine("That's not yours!")
				return
			}
			slot.Quantity += removed
			g.saveCharacter(p)
			sess.WriteLine(fmt.Sprintf("You pick up %d x %s. (now %d)", removed, coloredName, slot.Quantity))
			return
		}
		freeSlot := p.FirstFreeSlot()
		if freeSlot == -1 {
			sess.WriteLine("Your inventory is full.")
			return
		}
		removed, ok := g.World.RemoveReservedItem(p.RoomID, itemID, wanted, p.Name)
		if !ok {
			sess.WriteLine("That's not yours!")
			return
		}
		p.SetInvSlot(freeSlot, g.newInventorySlot(itemID, removed))
		g.saveCharacter(p)
		if removed == 1 {
			sess.WriteLine(fmt.Sprintf("You pick up a %s.", coloredName))
		} else {
			sess.WriteLine(fmt.Sprintf("You pick up %d x %s.", removed, coloredName))
		}
		return
	}

	picked := 0
	for picked < wanted {
		fs := p.FirstFreeSlot()
		if fs == -1 {
			break
		}
		_, ok := g.World.RemoveReservedItem(p.RoomID, itemID, 1, p.Name)
		if !ok {
			break
		}
		p.SetInvSlot(fs, g.newInventorySlot(itemID, 1))
		picked++
	}

	g.saveCharacter(p)
	if picked == 0 {
		sess.WriteLine("Your inventory is full.")
	} else if picked == 1 {
		sess.WriteLine(fmt.Sprintf("You pick up a %s.", coloredName))
	} else {
		sess.WriteLine(fmt.Sprintf("You pick up %d x %s.", picked, coloredName))
	}
	if picked < available {
		sess.WriteLine(fmt.Sprintf("You're only able to take %d x %s!", picked, coloredName))
	}
}

func (g *Game) doGetAll(sess *net.Session) {
	p := sess.Player
	g.cancelAction(p)
	// Only takeable stock counts (see doGet); the all-or-nothing
	// RemoveReservedItem then never aborts a partial pickup.
	ground := g.World.AccessibleGround(p.RoomID, p.Name)
	if len(ground) == 0 {
		sess.WriteLine("There's nothing on the ground to pick up.")
		return
	}

	var picked []string
	creditsCapped := false
	for itemID, qty := range ground {
		if qty <= 0 {
			continue
		}
		if itemID == "credits" {
			// Same capped-removal rule as pickupCredits: only the balance
			// headroom is taken, so credits at the cap stay on the ground
			// instead of being destroyed by the clamped grant.
			room := creditHeadroom(p)
			taken := 0
			if room > 0 {
				taken = g.World.RemoveAvailableItem(p.RoomID, itemID, room, p.Name)
			}
			if taken <= 0 {
				if room <= 0 {
					creditsCapped = true
				}
				continue
			}
			g.grantCredits(p, taken)
			if taken == 1 {
				picked = append(picked, "1 credit")
			} else {
				picked = append(picked, fmt.Sprintf("%d credits", taken))
			}
			continue
		}

		def, _ := g.ItemStore.Load(itemID)
		for qty > 0 {
			if def != nil && def.Stackable {
				stacked := false
				quality, maxQuality := g.pickedStackProps(itemID)
				for i := 0; i < 28; i++ {
					slot := p.InvSlot(i)
					if slot == nil || slot.ItemID != itemID || slot.Quality != quality || slot.MaxQuality != maxQuality {
						continue
					}
					_, ok := g.World.RemoveReservedItem(p.RoomID, itemID, qty, p.Name)
					if !ok {
						qty = 0
						stacked = true
						break
					}
					slot.Quantity += qty
					picked = append(picked, fmt.Sprintf("%s (now %d)", g.itemColorize(sess, def, def.Name), slot.Quantity))
					stacked = true
					qty = 0
					break
				}
				if stacked {
					break
				}
				freeSlot := p.FirstFreeSlot()
				if freeSlot == -1 {
					if len(picked) > 0 {
						sess.WriteLine("You can't hold everything but you picked up:")
						formatPickupList(sess, picked)
					} else {
						sess.WriteLine("Your inventory is full!")
					}
					g.saveCharacter(p)
					return
				}
				_, ok := g.World.RemoveReservedItem(p.RoomID, itemID, qty, p.Name)
				if !ok {
					break
				}
				p.SetInvSlot(freeSlot, g.newInventorySlot(itemID, qty))
				name := itemID
				if def != nil {
					name = def.Name
				}
				picked = append(picked, g.itemColorize(sess, def, name))
				break
			}

			freeSlot := p.FirstFreeSlot()
			if freeSlot == -1 {
				if len(picked) > 0 {
					sess.WriteLine("You can't hold everything but you picked up:")
					formatPickupList(sess, picked)
				} else {
					sess.WriteLine("Your inventory is full!")
				}
				g.saveCharacter(p)
				return
			}

			take := 1
			_, ok := g.World.RemoveReservedItem(p.RoomID, itemID, take, p.Name)
			if !ok {
				break
			}
			p.SetInvSlot(freeSlot, g.newInventorySlot(itemID, take))
			name := itemID
			if def != nil {
				name = def.Name
			}
			picked = append(picked, g.itemColorize(sess, def, name))
			qty -= take
		}
	}

	g.saveCharacter(p)

	if creditsCapped {
		sess.WriteLine(g.colorize(sess, "currency_pickup", "Your purse can't hold any more credits."))
	}
	switch {
	case len(picked) > 0:
		sess.Write("You picked up: ")
		formatPickupList(sess, picked)
	case !creditsCapped:
		sess.WriteLine("Your inventory is full.")
	}
}

func (g *Game) pickupCredits(sess *net.Session, p *player.Player, itemID string) {
	// The balance cap is a hard limit: credits the purse cannot absorb must
	// stay on the ground instead of being removed and then clamped away by
	// grantCredits. Only the headroom below the cap is taken.
	room := creditHeadroom(p)
	if room <= 0 {
		sess.WriteLine(g.colorize(sess, "currency_pickup", "Your purse can't hold any more credits."))
		return
	}
	qty := g.World.RemoveAvailableItem(p.RoomID, itemID, room, p.Name)
	if qty <= 0 {
		return
	}
	g.grantCredits(p, qty)
	g.saveCharacter(p)
	if qty == 1 {
		sess.WriteLine(g.colorize(sess, "currency_pickup", "You pick up 1 credit."))
	} else {
		sess.WriteLine(g.colorize(sess, "currency_pickup", fmt.Sprintf("You pick up %d credits. (total: %d)", qty, p.Credits)))
	}
}

// creditHeadroom is how many credits p's balance can still absorb before the
// economy cap (casino.MaxCredits) is reached.
func creditHeadroom(p *player.Player) int {
	room := casino.MaxCredits - p.Credits
	if room < 0 {
		return 0
	}
	return room
}

// pickedStackProps returns the Quality and MaxQuality a freshly picked-up
// stack receives (newInventorySlot stamps full quality onto quality-bearing
// items). A pickup only merges into a slot with matching properties, since
// merging a differently qualified stack would silently destroy the picked-up
// stack's quality - the same rule withdrawBankItem applies in cmd_bank.go.
// It reads the rule through stackProps so every other stack-creation site
// (craft, harvest, ammo removal) agrees on the same values.
func (g *Game) pickedStackProps(itemID string) (quality, maxQuality int) {
	def, _ := g.ItemStore.Load(itemID)
	return stackProps(def)
}

func (g *Game) collectMatches(input string, each func(func(itemID string, slot int) bool)) []itemMatch {
	var matches []itemMatch
	each(func(itemID string, slot int) bool {
		def, err := g.ItemStore.Load(itemID)
		if err != nil {
			return true
		}
		if def.MatchesName(input) {
			matches = append(matches, itemMatch{ID: itemID, Name: def.Name, Slot: slot})
		}
		return true
	})
	return matches
}

func (g *Game) findGroundMatches(input string, roomID int) []itemMatch {
	ground := g.World.GroundItems(roomID)
	return g.collectMatches(input, func(yield func(string, int) bool) {
		for itemID := range ground {
			if !yield(itemID, -1) {
				return
			}
		}
	})
}

func (g *Game) findInventoryMatches(input string, p *player.Player) []itemMatch {
	return g.collectMatches(input, func(yield func(string, int) bool) {
		for i := 0; i < 28; i++ {
			slot := p.InvSlot(i)
			if slot == nil {
				continue
			}
			if !yield(slot.ItemID, i) {
				return
			}
		}
	})
}

func (g *Game) executeGet(sess *net.Session, args []string, rawInput string) {
	if len(args) == 0 {
		sess.WriteLine("Get what?")
	} else if args[0] == "all" {
		if len(args) == 1 {
			g.doGetAll(sess)
		} else {
			g.doGetAllNamed(sess, strings.Join(args[1:], " "))
		}
	} else {
		g.doGet(sess, strings.Join(args, " "))
	}
}