package pipeline

import (
	"context"
	"strings"
	"sync"
	"time"

	"ai-operator/internal/ai/llm"
	"ai-operator/internal/ai/stt"
	"ai-operator/internal/ai/tts"
	"ai-operator/internal/media"
)

type FakeSTT struct {
	events chan stt.Event
	audio  int
}

func NewFakeSTT() *FakeSTT { return &FakeSTT{events: make(chan stt.Event, 16)} }

func (f *FakeSTT) Start(ctx context.Context, req stt.StreamRequest) error { return nil }

func (f *FakeSTT) SendAudio(ctx context.Context, chunk media.AudioChunk) error {
	f.audio += len(chunk.Data)
	f.events <- stt.Event{Type: stt.EventPartialTranscript, Text: "Сколько стоит", At: time.Now().UTC()}
	f.events <- stt.Event{Type: stt.EventCommittedTranscript, Text: "Сколько стоит первичное подключение газа?", Language: "ru", At: time.Now().UTC()}
	return nil
}

func (f *FakeSTT) Events() <-chan stt.Event { return f.events }

func (f *FakeSTT) Close(ctx context.Context) error {
	close(f.events)
	return nil
}

type FakeLLM struct {
	Text string
}

func (f FakeLLM) StreamGenerate(ctx context.Context, req llm.GenerateRequest) (<-chan llm.Event, error) {
	out := make(chan llm.Event, 8)
	text := f.Text
	if text == "" {
		text = "Первичное подключение газа к газовому оборудованию осуществляется бесплатно."
	}
	go func() {
		defer close(out)
		parts := strings.SplitAfter(text, " ")
		for _, p := range parts {
			if p != "" {
				out <- llm.Event{Type: llm.EventTextDelta, Text: p}
			}
		}
		out <- llm.Event{Type: llm.EventDone}
	}()
	return out, nil
}

type FakeTTSFactory struct {
	mu      sync.Mutex
	Texts   []string
	Starts  int
	Cancels int
}

func (f *FakeTTSFactory) New(language string) tts.StreamingTTS {
	return &FakeTTS{factory: f, audio: make(chan tts.AudioChunk, 16)}
}

type FakeTTS struct {
	factory *FakeTTSFactory
	audio   chan tts.AudioChunk
	closed  bool
}

func (f *FakeTTS) Start(ctx context.Context, req tts.TTSStreamRequest) error {
	f.factory.mu.Lock()
	f.factory.Starts++
	f.factory.mu.Unlock()
	return nil
}

func (f *FakeTTS) SendText(ctx context.Context, text string, flush bool) error {
	f.factory.mu.Lock()
	if text != "" {
		f.factory.Texts = append(f.factory.Texts, text)
	}
	f.factory.mu.Unlock()
	if text != "" {
		select {
		case f.audio <- tts.AudioChunk{Data: []byte{0, 1, 0, 1}, Timestamp: time.Now().UTC()}:
		default:
		}
	}
	if flush && text == "" {
		f.Close(ctx)
	}
	return nil
}

func (f *FakeTTS) Audio() <-chan tts.AudioChunk { return f.audio }

func (f *FakeTTS) Close(ctx context.Context) error {
	if !f.closed {
		close(f.audio)
		f.closed = true
	}
	return nil
}