package api

import (
	"net/http"
	"sync"
	"time"

	"git.sati.ac/sati.ac/bridge/config"
	"git.sati.ac/sati.ac/sati-go"
	"github.com/sirupsen/logrus"
)

type TaskState uint

const (
	StateProcessing TaskState = iota
	StateSuccess
	StateError
)

type Task struct {
	State      TaskState
	Entity     *sati.TaskEntity
	Result     any
	CreateTime int64
	EndTime    int64
}

type RegistryStats struct {
	Total      uint32
	Success    uint32
	Error      uint32
	Processing uint32
}

type TaskRegistry struct {
	mu        *sync.RWMutex
	config    *config.Config
	tasks     map[uint32]*Task
	idCounter uint32
	api       *sati.Api
	stats     RegistryStats
}

func NewTaskRegistry(api *sati.Api, config *config.Config) *TaskRegistry {
	return &TaskRegistry{
		mu:     &sync.RWMutex{},
		tasks:  map[uint32]*Task{},
		api:    api,
		config: config,
	}
}

func (t *TaskRegistry) CreateTask(task sati.AnyTask) uint32 {
	t.mu.Lock()
	t.idCounter++
	id := t.idCounter
	entry := &Task{
		State:      StateProcessing,
		CreateTime: time.Now().Unix(),
	}
	t.stats.Total++
	t.stats.Processing++
	t.tasks[id] = entry
	t.mu.Unlock()

	go func() {
		result := task.Result()
		entity, err := t.api.Solve(task, result)

		t.mu.Lock()
		t.stats.Processing--
		if err != nil {
			t.stats.Error++
			entry.State = StateError
		} else {
			t.stats.Success++
			entry.State = StateSuccess
			entry.Entity = entity
			entry.Result = result
		}
		entry.EndTime = time.Now().Unix()
		t.mu.Unlock()

		time.Sleep(time.Millisecond * time.Duration(t.config.TaskLifetime))
		t.mu.Lock()
		delete(t.tasks, id)
		t.mu.Unlock()
	}()

	return id
}

func (t *TaskRegistry) Stats() RegistryStats {
	t.mu.RLock()
	defer t.mu.RUnlock()
	return t.stats
}

func (t *TaskRegistry) Get(id uint32) *Task {
	if t.config.TaskGetDelay != 0 {
		time.Sleep(time.Millisecond * time.Duration(t.config.TaskGetDelay))
	}

	t.mu.RLock()
	defer t.mu.RUnlock()
	task := t.tasks[id]
	if task == nil {
		return nil
	}

	cloned := *task
	return &cloned
}

type ApiContext struct {
	Config   *config.Config
	Api      *sati.Api
	Registry *TaskRegistry
	Logger   *logrus.Logger
	Server   *ApiServer
}

type ApiHandler interface {
	Name() string
	Domains() []string
	ServeHTTP(w http.ResponseWriter, r *http.Request)
}

type ApiServer struct {
	handlers map[string]ApiHandler
	domains  map[string]ApiHandler
	ctx      *ApiContext
}

func (a *ApiServer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	a.ctx.Logger.WithFields(logrus.Fields{
		"method": r.Method,
		"host":   r.Host,
		"path":   r.URL.Path,
	}).Debug("request")

	handler, ok := a.domains[r.Host]
	if !ok {
		w.Header().Set("Content-Type", "text/plain")
		w.WriteHeader(400)
		w.Write([]byte("domain not found"))
		return
	}

	handler.ServeHTTP(w, r)
}

func (a *ApiServer) GetDomains() []string {
	domains := make([]string, 0, len(a.domains))

	for domain := range a.domains {
		domains = append(domains, domain)
	}

	return domains
}

func NewApiServer(ctx *ApiContext) *ApiServer {
	handlers := []ApiHandler{
		newStatsApi(ctx),
		newAntigateV2Api(ctx),
		newRuCaptchaApi(ctx),
	}

	server := &ApiServer{
		handlers: map[string]ApiHandler{},
		domains:  map[string]ApiHandler{},
		ctx:      ctx,
	}

	for _, handler := range handlers {
		server.handlers[handler.Name()] = handler
		for _, domain := range handler.Domains() {
			server.domains[domain] = handler
		}
	}

	for domain, handlerName := range ctx.Config.ExtraDomains {
		handler, ok := server.handlers[handlerName]
		if !ok {
			ctx.Logger.WithFields(logrus.Fields{
				"domain":  domain,
				"handler": handlerName,
			}).Warn("extraDomains: handler not found, ignoring it")
			continue
		}

		server.domains[domain] = handler
	}

	ctx.Server = server
	return server
}