internal/screen/screen.go

   1 package screen
   2
   3 import (
   4         "fmt"
   5         "os"
   6         "sync"
   7
   8         "github.com/zyedidia/micro/internal/config"
   9         "github.com/zyedidia/micro/pkg/terminfo"
  10         "github.com/zyedidia/tcell"
  11 )
  12
  13 // Screen is the tcell screen we use to draw to the terminal
  14 // Synchronization is used because we poll the screen on a separate
  15 // thread and sometimes the screen is shut down by the main thread
  16 // (for example on TermMessage) so we don't want to poll a nil/shutdown
  17 // screen. TODO: maybe we should worry about polling and drawing at the
  18 // same time too.
  19 var Screen tcell.Screen
  20 var lock sync.Mutex
  21 var DrawChan chan bool
  22
  23 func Lock() {
  24         lock.Lock()
  25 }
  26
  27 func Unlock() {
  28         lock.Unlock()
  29 }
  30
  31 func Redraw() {
  32         DrawChan <- true
  33 }
  34
  35 // TempFini shuts the screen down temporarily
  36 func TempFini() bool {
  37         screenWasNil := Screen == nil
  38
  39         if !screenWasNil {
  40                 Screen.Fini()
  41                 Lock()
  42                 Screen = nil
  43         }
  44         return screenWasNil
  45 }
  46
  47 // TempStart restarts the screen after it was temporarily disabled
  48 func TempStart(screenWasNil bool) {
  49         if !screenWasNil {
  50                 Init()
  51                 Unlock()
  52         }
  53 }
  54
  55 // Init creates and initializes the tcell screen
  56 func Init() {
  57         DrawChan = make(chan bool, 8)
  58
  59         // Should we enable true color?
  60         truecolor := os.Getenv("MICRO_TRUECOLOR") == "1"
  61
  62         tcelldb := os.Getenv("TCELLDB")
  63         os.Setenv("TCELLDB", config.ConfigDir+"/.tcelldb")
  64
  65         // In order to enable true color, we have to set the TERM to `xterm-truecolor` when
  66         // initializing tcell, but after that, we can set the TERM back to whatever it was
  67         oldTerm := os.Getenv("TERM")
  68         if truecolor {
  69                 os.Setenv("TERM", "xterm-truecolor")
  70         }
  71
  72         // Initilize tcell
  73         var err error
  74         Screen, err = tcell.NewScreen()
  75         if err != nil {
  76                 if err == tcell.ErrTermNotFound {
  77                         err = terminfo.WriteDB(config.ConfigDir + "/.tcelldb")
  78                         if err != nil {
  79                                 fmt.Println(err)
  80                                 fmt.Println("Fatal: Micro could not create terminal database file", config.ConfigDir+"/.tcelldb")
  81                                 os.Exit(1)
  82                         }
  83                         Screen, err = tcell.NewScreen()
  84                         if err != nil {
  85                                 fmt.Println(err)
  86                                 fmt.Println("Fatal: Micro could not initialize a Screen.")
  87                                 os.Exit(1)
  88                         }
  89                 } else {
  90                         fmt.Println(err)
  91                         fmt.Println("Fatal: Micro could not initialize a Screen.")
  92                         os.Exit(1)
  93                 }
  94         }
  95         if err = Screen.Init(); err != nil {
  96                 fmt.Println(err)
  97                 os.Exit(1)
  98         }
  99
 100         // Now we can put the TERM back to what it was before
 101         if truecolor {
 102                 os.Setenv("TERM", oldTerm)
 103         }
 104
 105         if config.GetGlobalOption("mouse").(bool) {
 106                 Screen.EnableMouse()
 107         }
 108
 109         os.Setenv("TCELLDB", tcelldb)
 110 }