// counter.go: death accounting.
//
// Deliberately has NOTHING Windows-specific: all memory reading lives in
// main.go. That keeps this part — which holds the actual rules (which
// character a death belongs to, what happens on a character switch, what
// to show with the game closed) — buildable and testable on any platform.
// All three times something counted wrong, the bug was here.
package main

import (
	"log"
	"strings"
	"sync"
)

// The total shown IS the one the game keeps for the loaded character. No
// adjustments or accumulators of our own: switching characters jumps the
// number to theirs on the very same reading.
type state struct {
	mu           sync.Mutex
	connected    bool
	playerLoaded bool
	rawDeaths    int32
	haveReading  bool
	bossFight    bool
	charName     string
	charKey      string
	slot         int
	total        int64
	announced    bool
	lastErr      string
}

type stateSnapshot struct {
	RawDeaths    int32
	Slot         int
	Total        int64
	BossFight    bool
	Connected    bool
	PlayerLoaded bool
	CharName     string
}

var st state
var totals *totalsStore

// init starts by showing the last known character, so the overlay has a
// sensible number before you even open the game.
func (s *state) init(store *totalsStore) {
	key, name, total := store.lastKnownTotal()
	s.mu.Lock()
	s.charName = name
	s.charKey = key
	s.slot = -1
	s.total = total
	s.mu.Unlock()
	if name != "" {
		log.Printf("last known character: %s with %d deaths", name, total)
	}
}

func (s *state) snapshot() stateSnapshot {
	s.mu.Lock()
	defer s.mu.Unlock()
	total := s.total
	if s.haveReading {
		total = int64(s.rawDeaths)
	}
	return stateSnapshot{
		RawDeaths:    s.rawDeaths,
		Slot:         s.slot,
		Total:        total,
		BossFight:    s.bossFight,
		Connected:    s.connected,
		PlayerLoaded: s.playerLoaded,
		CharName:     s.charName,
	}
}

func (s *state) name() string {
	s.mu.Lock()
	defer s.mu.Unlock()
	return s.charName
}

// displayName: whatever the config says wins; if it's empty, fall back to
// the character name read from the game.
func displayName(cfg config) string {
	if n := strings.TrimSpace(cfg.Name); n != "" {
		return n
	}
	if n := st.name(); n != "" {
		return n
	}
	// Empty on purpose: let the UI pick the label, since it's the one that
	// knows whether it's showing one player or two.
	return ""
}

// setCharacter is called when the loaded character changes: the total
// becomes whatever the game tracks for that character.
func (s *state) setCharacter(slot int, name string, raw int32) {
	key := characterKey(slot, name)
	if key == "" {
		return // neither slot nor name: no one to attribute this to
	}

	s.mu.Lock()
	if key == s.charKey && s.haveReading {
		// Same character: the name may have just shown up, since the slot
		// is read before the name.
		if name != "" && name != s.charName {
			s.charName = name
			total := s.total
			s.mu.Unlock()
			totals.save(key, charTotal{Name: name, Total: total})
			return
		}
		s.mu.Unlock()
		return
	}
	s.charKey = key
	s.slot = slot
	if name != "" {
		s.charName = name
	}
	name = s.charName
	// Adopt the new character's reading right away: otherwise the snapshot
	// would keep showing the PREVIOUS character's deaths until the next one.
	s.rawDeaths = raw
	s.haveReading = true
	s.total = int64(raw)
	total := s.total
	s.mu.Unlock()

	log.Printf("character: %s (slot %d) -> %d deaths", name, slot, total)
	totals.save(key, charTotal{Name: name, Total: total})
}

func (s *state) setReading(raw int32, boss bool) {
	s.mu.Lock()
	s.connected = true
	s.playerLoaded = true
	s.announced = false
	changed := !s.haveReading || s.rawDeaths != raw
	s.haveReading = true
	s.rawDeaths = raw
	s.bossFight = boss
	s.lastErr = ""
	total := int64(raw)
	grew := total > s.total
	s.total = total
	key, name := s.charKey, s.charName
	s.mu.Unlock()

	if !changed {
		return
	}
	if grew {
		log.Printf("new death for %s -> %d", name, total)
	}
	totals.save(key, charTotal{Name: name, Total: total})
}

// setPlayerUnloaded: the game is still open but there's no character in
// the world (main menu or a loading screen). Unlike a disconnect, this
// does NOT clear connected: the overlay has to keep showing the total
// instead of a dash, or it would flicker on every loading screen (i.e.
// every death).
func (s *state) setPlayerUnloaded(reason string) {
	s.mu.Lock()
	was := s.playerLoaded
	first := !s.announced
	s.announced = true
	s.connected = true
	s.playerLoaded = false
	s.bossFight = false
	s.lastErr = reason
	s.mu.Unlock()
	if was || first {
		log.Printf("no character loaded (%s) - total stays frozen until you're back in the world", reason)
	}
}

func (s *state) setDisconnected(reason string) {
	s.mu.Lock()
	wasConnected := s.connected
	s.connected = false
	s.playerLoaded = false
	s.bossFight = false
	s.lastErr = reason
	s.mu.Unlock()
	if wasConnected {
		log.Printf("lost the connection to the game: %s", reason)
	}
}