package widgets
import (
"bufio"
"errors"
"fmt"
"io"
"os/exec"
"regexp"
"strings"
"github.com/danwakefield/fnmatch"
"github.com/emersion/go-message"
_ "github.com/emersion/go-message/charset"
"github.com/emersion/go-message/mail"
"github.com/gdamore/tcell"
"github.com/google/shlex"
"github.com/mattn/go-runewidth"
"git.sr.ht/~sircmpwn/aerc/config"
"git.sr.ht/~sircmpwn/aerc/lib"
"git.sr.ht/~sircmpwn/aerc/lib/ui"
"git.sr.ht/~sircmpwn/aerc/models"
)
var ansi = regexp.MustCompile("^\x1B\\[[0-?]*[ -/]*[@-~]")
type MessageViewer struct {
ui.Invalidatable
acct *AccountView
conf *config.AercConfig
err error
grid *ui.Grid
msg *models.MessageInfo
switcher *PartSwitcher
store *lib.MessageStore
}
type PartSwitcher struct {
ui.Invalidatable
parts []*PartViewer
selected int
showHeaders bool
alwaysShowMime bool
}
func NewMessageViewer(acct *AccountView, conf *config.AercConfig,
store *lib.MessageStore, msg *models.MessageInfo) *MessageViewer {
header, headerHeight := createHeader(msg, conf.Viewer.HeaderLayout)
grid := ui.NewGrid().Rows([]ui.GridSpec{
{ui.SIZE_EXACT, headerHeight},
{ui.SIZE_WEIGHT, 1},
}).Columns([]ui.GridSpec{
{ui.SIZE_WEIGHT, 1},
})
switcher := &PartSwitcher{}
switcher.selected = -1
err := createSwitcher(switcher, conf, store, msg)
if err != nil {
return &MessageViewer{
err: err,
grid: grid,
msg: msg,
}
}
grid.AddChild(header).At(0, 0)
grid.AddChild(switcher).At(1, 0)
return &MessageViewer{
acct: acct,
conf: conf,
grid: grid,
msg: msg,
store: store,
switcher: switcher,
}
}
func createHeader(msg *models.MessageInfo, layout [][]string) (grid *ui.Grid, height int) {
presentHeaders := presentHeaders(msg, layout)
rowCount := len(presentHeaders) + 1 // extra row for spacer
grid = ui.MakeGrid(rowCount, 1, ui.SIZE_EXACT, ui.SIZE_WEIGHT)
for i, cols := range presentHeaders {
r := ui.MakeGrid(1, len(cols), ui.SIZE_EXACT, ui.SIZE_WEIGHT)
for j, col := range cols {
r.AddChild(
&HeaderView{
Name: col,
Value: fmtHeader(msg, col),
}).At(0, j)
}
grid.AddChild(r).At(i, 0)
}
grid.AddChild(ui.NewFill(' ')).At(rowCount-1, 0)
return grid, rowCount
}
// presentHeaders returns a filtered header layout, removing rows whose headers
// do not appear in the provided message.
func presentHeaders(msg *models.MessageInfo, layout [][]string) [][]string {
headers := msg.RFC822Headers
result := make([][]string, 0, len(layout))
for _, row := range layout {
// To preserve layout alignment, only hide rows if all columns are empty
for _, col := range row {
if headers.Get(col) != "" {
result = append(result, row)
break
}
}
}
return result
}
func fmtHeader(msg *models.MessageInfo, header string) string {
switch header {
case "From":
return models.FormatAddresses(msg.Envelope.From)
case "To":
return models.FormatAddresses(msg.Envelope.To)
case "Cc":
return models.FormatAddresses(msg.Envelope.Cc)
case "Bcc":
return models.FormatAddresses(msg.Envelope.Bcc)
case "Date":
return msg.Envelope.Date.Format("Mon Jan 2, 2006 at 3:04 PM")
case "Subject":
return msg.Envelope.Subject
default:
return msg.RFC822Headers.Get(header)
}
}
func enumerateParts(conf *config.AercConfig, store *lib.MessageStore,
msg *models.MessageInfo, body *models.BodyStructure,
index []int) ([]*PartViewer, error) {
var parts []*PartViewer
for i, part := range body.Parts {
curindex := append(index, i+1)
if part.MIMEType == "multipart" {
// Multipart meta-parts are faked
pv := &PartViewer{part: part}
parts = append(parts, pv)
subParts, err := enumerateParts(
conf, store, msg, part, curindex)
if err != nil {
return nil, err
}
parts = append(parts, subParts...)
continue
}
pv, err := NewPartViewer(conf, store, msg, part, curindex)
if err != nil {
return nil, err
}
parts = append(parts, pv)
}
return parts, nil
}
func createSwitcher(switcher *PartSwitcher, conf *config.AercConfig,
store *lib.MessageStore, msg *models.MessageInfo) error {
var err error
switcher.showHeaders = conf.Viewer.ShowHeaders
switcher.alwaysShowMime = conf.Viewer.AlwaysShowMime
if len(msg.BodyStructure.Parts) == 0 {
switcher.selected = 0
pv, err := NewPartViewer(conf, store, msg, msg.BodyStructure, []int{1})
if err != nil {
return err
}
switcher.parts = []*PartViewer{pv}
pv.OnInvalidate(func(_ ui.Drawable) {
switcher.Invalidate()
})
} else {
switcher.parts, err = enumerateParts(conf, store,
msg, msg.BodyStructure, []int{})
if err != nil {
return err
}
selectedPriority := -1
for i, pv := range switcher.parts {
pv.OnInvalidate(func(_ ui.Drawable) {
switcher.Invalidate()
})
// Switch to user's preferred mimetype
if switcher.selected == -1 && pv.part.MIMEType != "multipart" {
switcher.selected = i
} else if selectedPriority == -1 {
for idx, m := range conf.Viewer.Alternatives {
if m != pv.part.MIMEType+"/"+pv.part.MIMESubType {
continue
}
priority := len(conf.Viewer.Alternatives) - idx
if priority > selectedPriority {
selectedPriority = priority
switcher.selected = i
}
}
}
}
}
return nil
}
func (mv *MessageViewer) Draw(ctx *ui.Context) {
if mv.err != nil {
ctx.Fill(0, 0, ctx.Width(), ctx.Height(), ' ', tcell.StyleDefault)
ctx.Printf(0, 0, tcell.StyleDefault, "%s", mv.err.Error())
return
}
mv.grid.Draw(ctx)
}
func (mv *MessageViewer) Invalidate() {
mv.grid.Invalidate()
}
func (mv *MessageViewer) OnInvalidate(fn func(d ui.Drawable)) {
mv.grid.OnInvalidate(func(_ ui.Drawable) {
fn(mv)
})
}
func (mv *MessageViewer) Store() *lib.MessageStore {
return mv.store
}
func (mv *MessageViewer) SelectedAccount() *AccountView {
return mv.acct
}
func (mv *MessageViewer) SelectedMessage() (*models.MessageInfo, error) {
if mv.msg == nil {
return nil, errors.New("no message selected")
}
return mv.msg, nil
}
func (mv *MessageViewer) ToggleHeaders() {
switcher := mv.switcher
mv.conf.Viewer.ShowHeaders = !mv.conf.Viewer.ShowHeaders
err := createSwitcher(
switcher, mv.conf, mv.store, mv.msg)
if err != nil {
mv.acct.Logger().Printf(
"warning: error during create switcher - %v", err)
}
switcher.Invalidate()
}
func (mv *MessageViewer) SelectedMessagePart() *PartInfo {
switcher := mv.switcher
part := switcher.parts[switcher.selected]
return &PartInfo{
Index: part.index,
Msg: part.msg,
Part: part.part,
Store: part.store,
}
}
func (mv *MessageViewer) PreviousPart() {
switcher := mv.switcher
for {
switcher.selected--
if switcher.selected < 0 {
switcher.selected = len(switcher.parts) - 1
}
if switcher.parts[switcher.selected].part.MIMEType != "multipart" {
break
}
}
mv.Invalidate()
}
func (mv *MessageViewer) NextPart() {
switcher := mv.switcher
for {
switcher.selected++
if switcher.selected >= len(switcher.parts) {
switcher.selected = 0
}
if switcher.parts[switcher.selected].part.MIMEType != "multipart" {
break
}
}
mv.Invalidate()
}
func (ps *PartSwitcher) Invalidate() {
ps.DoInvalidate(ps)
}
func (ps *PartSwitcher) Focus(focus bool) {
if ps.parts[ps.selected].term != nil {
ps.parts[ps.selected].term.Focus(focus)
}
}
func (ps *PartSwitcher) Event(event tcell.Event) bool {
if ps.parts[ps.selected].term != nil {
return ps.parts[ps.selected].term.Event(event)
}
return false
}
func (ps *PartSwitcher) Draw(ctx *ui.Context) {
height := len(ps.parts)
if height == 1 && !ps.alwaysShowMime {
ps.parts[ps.selected].Draw(ctx)
return
}
// TODO: cap height and add scrolling for messages with many parts
y := ctx.Height() - height
for i, part := range ps.parts {
style := tcell.StyleDefault.Reverse(ps.selected == i)
ctx.Fill(0, y+i, ctx.Width(), 1, ' ', style)
name := fmt.Sprintf("%s/%s",
strings.ToLower(part.part.MIMEType),
strings.ToLower(part.part.MIMESubType))
if filename, ok := part.part.DispositionParams["filename"]; ok {
name += fmt.Sprintf(" (%s)", filename)
}
ctx.Printf(len(part.index)*2, y+i, style, "%s", name)
}
ps.parts[ps.selected].Draw(ctx.Subcontext(
0, 0, ctx.Width(), ctx.Height()-height))
}
func (mv *MessageViewer) Event(event tcell.Event) bool {
return mv.switcher.Event(event)
}
func (mv *MessageViewer) Focus(focus bool) {
mv.switcher.Focus(focus)
}
type PartViewer struct {
ui.Invalidatable
err error
fetched bool
filter *exec.Cmd
index []int
msg *models.MessageInfo
pager *exec.Cmd
pagerin io.WriteCloser
part *models.BodyStructure
showHeaders bool
sink io.WriteCloser
source io.Reader
store *lib.MessageStore
term *Terminal
}
func NewPartViewer(conf *config.AercConfig,
store *lib.MessageStore, msg *models.MessageInfo,
part *models.BodyStructure,
index []int) (*PartViewer, error) {
var (
filter *exec.Cmd
pager *exec.Cmd
pipe io.WriteCloser
pagerin io.WriteCloser
term *Terminal
)
cmd, err := shlex.Split(conf.Viewer.Pager)
if err != nil {
return nil, err
}
pager = exec.Command(cmd[0], cmd[1:]...)
for _, f := range conf.Filters {
mime := strings.ToLower(part.MIMEType) +
"/" + strings.ToLower(part.MIMESubType)
switch f.FilterType {
case config.FILTER_MIMETYPE:
if fnmatch.Match(f.Filter, mime, 0) {
filter = exec.Command("sh", "-c", f.Command)
}
case config.FILTER_HEADER:
var header string
switch f.Header {
case "subject":
header = msg.Envelope.Subject
case "from":
header = models.FormatAddresses(msg.Envelope.From)
case "to":
header = models.FormatAddresses(msg.Envelope.To)
case "cc":
header = models.FormatAddresses(msg.Envelope.Cc)
}
if f.Regex.Match([]byte(header)) {
filter = exec.Command("sh", "-c", f.Command)
}
}
if filter != nil {
break
}
}
if filter != nil {
if pipe, err = filter.StdinPipe(); err != nil {
return nil, err
}
if pagerin, _ = pager.StdinPipe(); err != nil {
return nil, err
}
if term, err = NewTerminal(pager); err != nil {
return nil, err
}
}
pv := &PartViewer{
filter: filter,
index: index,
msg: msg,
pager: pager,
pagerin: pagerin,
part: part,
showHeaders: conf.Viewer.ShowHeaders,
sink: pipe,
store: store,
term: term,
}
if term != nil {
term.OnStart = func() {
pv.attemptCopy()
}
term.OnInvalidate(func(_ ui.Drawable) {
pv.Invalidate()
})
}
return pv, nil
}
func (pv *PartViewer) SetSource(reader io.Reader) {
pv.source = reader
pv.attemptCopy()
}
func (pv *PartViewer) attemptCopy() {
if pv.source != nil && pv.pager.Process != nil {
header := message.Header{}
header.SetText("Content-Transfer-Encoding", pv.part.Encoding)
header.SetContentType(pv.part.MIMEType, pv.part.Params)
header.SetText("Content-Description", pv.part.Description)
if pv.filter != nil {
stdout, _ := pv.filter.StdoutPipe()
stderr, _ := pv.filter.StderrPipe()
pv.filter.Start()
ch := make(chan interface{})
go func() {
_, err := io.Copy(pv.pagerin, stdout)
if err != nil {
pv.err = err
pv.Invalidate()
}
stdout.Close()
ch <- nil
}()
go func() {
_, err := io.Copy(pv.pagerin, stderr)
if err != nil {
pv.err = err
pv.Invalidate()
}
stderr.Close()
ch <- nil
}()
go func() {
<-ch
<-ch
pv.pagerin.Close()
}()
}
go func() {
if pv.showHeaders && pv.msg.RFC822Headers != nil {
fields := pv.msg.RFC822Headers.Fields()
for fields.Next() {
field := fmt.Sprintf(
"%s: %s\n", fields.Key(), fields.Value())
pv.sink.Write([]byte(field))
}
pv.sink.Write([]byte{'\n'})
}
entity, err := message.New(header, pv.source)
if err != nil {
pv.err = err
pv.Invalidate()
return
}
reader := mail.NewReader(entity)
part, err := reader.NextPart()
if err != nil {
pv.err = err
pv.Invalidate()
return
}
if pv.part.MIMEType == "text" {
scanner := bufio.NewScanner(part.Body)
for scanner.Scan() {
text := scanner.Text()
text = ansi.ReplaceAllString(text, "")
io.WriteString(pv.sink, text+"\n")
}
} else {
io.Copy(pv.sink, part.Body)
}
pv.sink.Close()
}()
}
}
func (pv *PartViewer) Invalidate() {
pv.DoInvalidate(pv)
}
func (pv *PartViewer) Draw(ctx *ui.Context) {
if pv.filter == nil {
// TODO: Let them download it directly or something
ctx.Fill(0, 0, ctx.Width(), ctx.Height(), ' ', tcell.StyleDefault)
ctx.Printf(0, 0, tcell.StyleDefault.Foreground(tcell.ColorRed),
"No filter configured for this mimetype")
return
}
if !pv.fetched {
pv.store.FetchBodyPart(pv.msg.Uid, pv.index, pv.SetSource)
pv.fetched = true
}
if pv.err != nil {
ctx.Fill(0, 0, ctx.Width(), ctx.Height(), ' ', tcell.StyleDefault)
ctx.Printf(0, 0, tcell.StyleDefault, "%s", pv.err.Error())
return
}
pv.term.Draw(ctx)
}
type HeaderView struct {
ui.Invalidatable
Name string
Value string
}
func (hv *HeaderView) Draw(ctx *ui.Context) {
name := hv.Name
size := runewidth.StringWidth(name)
lim := ctx.Width() - size - 1
value := runewidth.Truncate(" "+hv.Value, lim, "…")
var (
hstyle tcell.Style
vstyle tcell.Style
)
// TODO: Make this more robust and less dumb
if hv.Name == "PGP" {
vstyle = tcell.StyleDefault.Foreground(tcell.ColorGreen)
hstyle = tcell.StyleDefault.Bold(true)
} else {
vstyle = tcell.StyleDefault
hstyle = tcell.StyleDefault.Bold(true)
}
ctx.Fill(0, 0, ctx.Width(), ctx.Height(), ' ', vstyle)
ctx.Printf(0, 0, hstyle, name)
ctx.Printf(size, 0, vstyle, value)
}
func (hv *HeaderView) Invalidate() {
hv.DoInvalidate(hv)
}