package buffer_test

import (
	"bytes"
	"code.squareroundforest.org/arpio/buffer"
	"testing"
	"time"
)

func TestBlock(t *testing.T) {
	t.Run("read", func(t *testing.T) {
		segmentSize := 1 << 12
		blockAfter := segmentSize
		bc := make(chan struct{})
		g := &gen{
			max:        1 << 15,
			blockAfter: []int{blockAfter},
			unblock:    map[int]<-chan struct{}{blockAfter: bc},
		}

		r := buffer.BufferedReader(g, buffer.Options{BufferPool: buffer.NoPool(segmentSize)})
		b := make([]byte, 2*segmentSize)
		if n, err := r.Read(b); n != segmentSize || err != nil {
			t.Fatal(n, err)
		}

		if string(b[:segmentSize]) != string(generate(segmentSize)) {
			t.Log(string(b))
			t.Log(string(generate(segmentSize)))
			t.Fatal("invalid content 1")
		}

		ubc := make(chan struct{})
		go func() {
			if n, err := r.Read(b); n != segmentSize || err != nil {
				t.Fatal(n, err)
			}

			if string(b[:segmentSize]) != string(generate(2 * segmentSize)[segmentSize:]) {
				t.Fatal("invalid content 2")
			}

			close(ubc)
		}()

		select {
		case <-time.After(10 * time.Millisecond):
		case <-ubc:
			t.Fatal("unexpected read return")
		}

		close(bc)
		select {
		case <-time.After(10 * time.Millisecond):
			t.Fatal("timeout")
		case <-ubc:
		}
	})

	t.Run("read bytes", func(t *testing.T) {
		segmentSize := 1 << 12
		blockAfter := segmentSize
		bc := make(chan struct{})
		g := &gen{
			max:        1 << 15,
			blockAfter: []int{blockAfter},
			unblock:    map[int]<-chan struct{}{blockAfter: bc},
		}

		r := buffer.BufferedReader(g, buffer.Options{BufferPool: buffer.NoPool(segmentSize)})
		ubc := make(chan struct{})
		go func() {
			if b, err := r.ReadBytes([]byte("123"), 2*segmentSize); len(b) != 0 || err != nil {
				t.Fatal(len(b), err)
			}

			close(ubc)
		}()

		select {
		case <-time.After(10 * time.Millisecond):
		case <-ubc:
			t.Fatal("unexpected read return")
		}

		close(bc)
		select {
		case <-time.After(10 * time.Millisecond):
			t.Fatal("timeout")
		case <-ubc:
		}
	})

	t.Run("read utf8", func(t *testing.T) {
		segmentSize := 1 << 12
		blockAfter := segmentSize
		bc := make(chan struct{})
		g := &gen{
			max:        1 << 15,
			blockAfter: []int{blockAfter},
			unblock:    map[int]<-chan struct{}{blockAfter: bc},
		}

		r := buffer.BufferedReader(g, buffer.Options{BufferPool: buffer.NoPool(segmentSize)})
		ubc := make(chan struct{})
		go func() {
			if r, n, err := r.ReadUTF8(2 * segmentSize); len(r) != 2*segmentSize ||
				n != 2*segmentSize ||
				err != nil {
				t.Fatal(len(r), err)
			}

			close(ubc)
		}()

		select {
		case <-time.After(10 * time.Millisecond):
		case <-ubc:
			t.Fatal("unexpected read return")
		}

		close(bc)
		select {
		case <-time.After(10 * time.Millisecond):
			t.Fatal("timeout")
		case <-ubc:
		}
	})

	t.Run("peek", func(t *testing.T) {
		segmentSize := 1 << 12
		blockAfter := segmentSize
		bc := make(chan struct{})
		g := &gen{
			max:        1 << 15,
			blockAfter: []int{blockAfter},
			unblock:    map[int]<-chan struct{}{blockAfter: bc},
		}

		r := buffer.BufferedReader(g, buffer.Options{BufferPool: buffer.NoPool(segmentSize)})
		ubc := make(chan struct{})
		go func() {
			if b, err := r.Peek(2 * segmentSize); len(b) != 2*segmentSize || err != nil {
				t.Fatal(len(b), err)
			}

			close(ubc)
		}()

		select {
		case <-time.After(10 * time.Millisecond):
		case <-ubc:
			t.Fatal("unexpected read return")
		}

		close(bc)
		select {
		case <-time.After(10 * time.Millisecond):
			t.Fatal("timeout")
		case <-ubc:
		}
	})

	t.Run("write to", func(t *testing.T) {
		segmentSize := 1 << 12
		blockAfter := segmentSize
		bc := make(chan struct{})
		g := &gen{
			max:        1 << 15,
			blockAfter: []int{blockAfter},
			unblock:    map[int]<-chan struct{}{blockAfter: bc},
		}

		r := buffer.BufferedReader(g, buffer.Options{BufferPool: buffer.NoPool(segmentSize)})
		ubc := make(chan struct{})
		go func() {
			var b bytes.Buffer
			if n, err := r.WriteTo(&b); n != 1<<15 || err != nil {
				t.Fatal(b, err)
			}

			close(ubc)
		}()

		select {
		case <-time.After(10 * time.Millisecond):
		case <-ubc:
			t.Fatal("unexpected read return")
		}

		close(bc)
		select {
		case <-time.After(10 * time.Millisecond):
			t.Fatal("timeout")
		case <-ubc:
		}
	})
}