//go:build js && wasm

package ultraviolet

import (
	"context"
	"fmt"
	"sync"

	fw "git.buran.team/main/fairwind"
)

type UVContext struct {
	ctx     context.Context
	log     *fw.Log
	mutex   sync.Mutex
	factory Factory
	state   *State
	source  *Source
	values  []Value
	router  *Router
}

func NewUVContext(ctx context.Context, log *fw.Log, platform int, routing Routing) (*UVContext, error) {
	this := &UVContext{
		ctx:     ctx,
		factory: NewFactory(platform),
		state:   NewStateWithOpts(ctx),
		values:  []Value{},
	}

	router, err := NewRouter(ctx, log, this, routing)
	if err != nil {
		return nil, fmt.Errorf("can't create uv-context: %w", err)
	}

	this.router = router
	this.source = NewSource(ctx, this.state)
	return this, nil
}

func (this *UVContext) Start() error {
	err := this.state.Start()
	if err != nil {
		return fmt.Errorf("can't start context: %w", err)
	}

	err = this.source.Start()
	if err != nil {
		return fmt.Errorf("can't start context: %w", err)
	}

	return nil
}

func (this *UVContext) Stop() error {
	err := this.state.Stop()
	if err != nil {
		return fmt.Errorf("can't stop context: %w", err)
	}

	err = this.source.Stop()
	if err != nil {
		return fmt.Errorf("can't stop context: %w", err)
	}

	for _, value := range this.values {
		err = value.Stop()
		if err != nil {
			return fmt.Errorf("can't stop context: %w", err)
		}
	}

	return nil
}

func (this *UVContext) Update() {
	this.router.Update()
}

func (this *UVContext) Factory() Factory {
	return this.factory
}

func (this *UVContext) Router() *Router {
	return this.router
}

func (this *UVContext) State() *State {
	return this.state
}

func (this *UVContext) Value(expression string) (Value, error) {
	this.mutex.Lock()
	defer this.mutex.Unlock()

	result := NewValueReactive(this.ctx, this.source, ExpressionToSelector(expression))
	err := result.Start()
	if err != nil {
		return nil, fmt.Errorf("can't create value: %w", err)
	}

	this.values = append(this.values, result)
	return result, nil
}