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|
package main
import (
"bytes"
"fmt"
tea "github.com/charmbracelet/bubbletea"
"math/rand"
"os"
"time"
)
type point struct {
x, y int
}
type direction int
const (
up = iota
right
down
left
)
func (d direction) toByte() byte {
return []byte{'^', '>', 'v', '<'}[d]
}
type tickMsg time.Time
type model struct {
dx, dy int
head point
tail []point
maxLen int
dir, newDir direction
food point
points int
}
func (m model) toOffset(p point) int {
return p.y*(m.dx+1) + p.x
}
func (m model) isEmpty(p point) bool {
// Check collision with head
if p == m.head {
return false
}
// Check collision with borders
if p.x < 0 || p.x >= m.dx || p.y < 0 || p.y >= m.dy {
return false
}
// Check collision with tail
for _, t := range m.tail {
if p == t {
return false
}
}
return true
}
func (m model) randFood() point {
candidate := point{x: rand.Intn(m.dx), y: rand.Intn(m.dy)}
for !m.isEmpty(candidate) {
candidate = point{x: rand.Intn(m.dx), y: rand.Intn(m.dy)}
}
return candidate
}
func initialModel() model {
m := model{
dx: 20,
dy: 10,
head: point{1, 1},
tail: make([]point, 0, 10),
maxLen: 5,
dir: right,
newDir: right,
points: 0,
}
m.food = m.randFood()
return m
}
func tickCmd(points int) func() tea.Msg {
base := 300
scaled := base - (10 * points)
return tea.Tick(time.Millisecond*time.Duration(scaled), func(t time.Time) tea.Msg {
return tickMsg(t)
})
}
func (m model) Init() tea.Cmd {
return tickCmd(m.points)
}
func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
switch msg := msg.(type) {
case tea.KeyMsg:
var newDir direction
switch msg.String() {
case "ctrl+c":
return m, tea.Quit
case "up", "k":
newDir = up
case "right", "l":
newDir = right
case "down", "j":
newDir = down
case "left", "h":
newDir = left
}
// Prevent from going in the reverse direction
if (newDir+2)%4 != m.dir {
m.newDir = newDir
}
case tickMsg:
// Calculate new head position
var newHead point
switch m.newDir {
case up:
newHead = point{m.head.x, m.head.y - 1}
case right:
newHead = point{m.head.x + 1, m.head.y}
case down:
newHead = point{m.head.x, m.head.y + 1}
case left:
newHead = point{m.head.x - 1, m.head.y}
}
m.dir = m.newDir
if !m.isEmpty(newHead) {
fmt.Println("DEP, siempre saludaba.")
return m, tea.Quit
}
// Good to go; update head and tail
m.tail = append(m.tail, m.head)
if len(m.tail) >= m.maxLen {
m.tail = m.tail[1:]
}
m.head = newHead
// Finally, when the snake eats the food:
if m.head == m.food {
m.food = m.randFood()
m.maxLen += 1
m.points += 1
}
return m, tickCmd(m.points)
}
return m, nil
}
func (m model) View() string {
// Generate board
row := append(bytes.Repeat([]byte{'-'}, m.dx), '\n')
board := bytes.Repeat(row, m.dy)
// Draw head
board[m.toOffset(m.head)] = m.dir.toByte()
// Draw tail
for _, p := range m.tail {
board[m.toOffset(p)] = '#'
}
// Draw food
board[m.toOffset(m.food)] = 'o'
return fmt.Sprintf("%s\nPoints: %d\n", string(board), m.points)
}
func main() {
rand.Seed(time.Now().UnixNano())
p := tea.NewProgram(initialModel())
if err := p.Start(); err != nil {
fmt.Println(err)
os.Exit(1)
}
}
|
