package main

import (
	"encoding/json"
	"io"
	"net/http"
	"sync"
	"time"

	"github.com/golang/freetype/truetype"
)

type Config struct {
	TimeAPIURL string `json:"timeApiUrl"`
}

type appPaths struct {
	ConfigFile  string
	AccountFile string
	LogDir      string
	SuccessDir  string
	FontFiles   []string
}

type TraceConfig struct {
	Enabled      bool
	MaxBodyBytes int
}

type Account struct {
	Name     string `json:"name"`
	Password string `json:"password"`
	Cookie   string `json:"cookie"`
}

type Product struct {
	CommodityID   string `json:"commodityId"`
	CommodityName string `json:"commodityName"`
	Score         int    `json:"score"`
	Count         int    `json:"count"`
	Pic           string `json:"pic"`
	Status        int    `json:"status"`
	OpenStatus    int    `json:"openStatus"`
	StoreStatus   int    `json:"storeStatus"`
	TimeLimited   int    `json:"timeLimited"`
	CountLimited  int    `json:"countLimited"`
	EliteLimited  int    `json:"eliteLimited"`
}

type ProductPayload struct {
	Success   bool      `json:"success"`
	Source    string    `json:"source"`
	Products  []Product `json:"products"`
	Count     int       `json:"count"`
	FetchedAt string    `json:"fetchedAt"`
	AgeSecond int       `json:"ageSecond"`
	Stale     bool      `json:"stale"`
}

type AccountView struct {
	Index  int    `json:"index"`
	Name   string `json:"name"`
	Cookie string `json:"cookie"`
}

type SeckillRequest struct {
	AccountProducts map[string]string `json:"accountProducts"`
	TargetTime      string            `json:"targetTime"`
	Advance         int               `json:"advance"`
}

type APIResponse struct {
	Error int             `json:"error"`
	Msg   string          `json:"msg"`
	Data  json.RawMessage `json:"data"`
}

type LogEntry struct {
	ID       int64  `json:"id"`
	Time     string `json:"time"`
	Level    string `json:"level"`
	Category string `json:"category"`
	Message  string `json:"message"`
}

type appState struct {
	config Config
	paths  appPaths
	client *DouyuClient
	logs   *memoryLogStore
	trace  *traceRecorder

	accountsMu sync.RWMutex
	accounts   []Account

	productsMu sync.RWMutex
	products   []Product
	productsAt time.Time

	resultsMu sync.RWMutex
	results   map[string]string

	scheduleMu     sync.Mutex
	schedule       *time.Timer
	warmupSchedule *time.Timer
	resyncSchedule *time.Timer

	warmupsMu sync.RWMutex
	warmups   map[string]WarmupData

	fontMu sync.Mutex
	font   *truetype.Font
}

type DouyuClient struct {
	httpClient *http.Client
	timeAPIURL string
	trace      *traceRecorder
}

type traceRecorder struct {
	enabled      bool
	maxBodyBytes int
	writer       *asyncLogWriter
	filePath     string
	seq          uint64
}

type asyncLogWriter struct {
	dst     io.Writer
	ch      chan []byte
	wg      sync.WaitGroup
	closed  uint32
	dropped uint64
}

type ExchangeAttempt struct {
	Account Account
	Product Product
	Index   int
}

type ExchangeResult struct {
	OK       bool
	Account  string
	Product  string
	Attempt  int
	RoleName string
	Message  string
}

type TimeSample struct {
	ServerTime     time.Time
	LocalTime      time.Time
	RTT            time.Duration
	Offset         time.Duration
	ErrorBound     time.Duration
	RawCurrentTime int64
	Samples        int
	Source         string
	Fallback       bool
}

type TimeCalibration struct {
	Offset     time.Duration
	ErrorBound time.Duration
	RTT        time.Duration
	Samples    int
	CreatedAt  time.Time
	Source     string
	Fallback   bool
}

func (c TimeCalibration) EstimatedServerNow() time.Time {
	if c.CreatedAt.IsZero() {
		return time.Now().UTC()
	}
	return time.Now().Add(c.Offset).UTC()
}

func (c TimeCalibration) IsZero() bool {
	return c.CreatedAt.IsZero()
}

type WarmupData struct {
	CSRF      string
	RoleName  string
	CreatedAt time.Time
}

// EstimatedServerNow 根据采样偏移估算当前斗鱼时间。
func (t TimeSample) EstimatedServerNow() time.Time {
	if t.LocalTime.IsZero() {
		return t.ServerTime
	}
	return time.Now().Add(t.Offset).UTC()
}

type memoryLogStore struct {
	mu       sync.RWMutex
	nextID   int64
	max      int
	filePath string
	entries  []LogEntry
}

var state = &appState{
	config:  Config{TimeAPIURL: defaultTimeAPI},
	results: make(map[string]string),
}