func (f *File) evalAdr(pa padr.Node, reverse bool, start int) (Adr, error) {
if reverse {
pa.Val = -pa.Val
}
switch pa.Type {
case padr.DOLLAR:
return Adr{Start: f.f.Length(), End: f.f.Length()}, nil
case padr.DOT:
return f.dot, nil
case padr.ADRMARK:
return adrmark, nil
case padr.HASH:
no, _ := f.f.OffsetRune(pa.Val, start)
return Adr{Start: no, End: no}, nil
case padr.NUMBER:
if pa.Val == 0 {
ind, _ := f.f.OffsetLine(0, start)
return Adr{Start: ind, End: ind}, nil
} else if pa.Val > 0 {
pa.Val--
st, _ := f.f.OffsetLine(pa.Val, start)
en, _ := f.f.OffsetLine(1, st)
return Adr{Start: st, End: en}, nil
} else if pa.Val < 0 {
pa.Val++
en, _ := f.f.OffsetLine(pa.Val, start)
st, _ := f.f.OffsetLine(-1, en)
return Adr{Start: st, End: en}, nil
}
case padr.REG:
if reverse {
reg, e := regexp.CompileReverse(pa.Reg)
if e != nil {
return Adr{}, e
}
rd := f.f.BackwardsReader(start)
ind := reg.FindReaderIndex(rd)
if ind == nil { // No match
return Adr{Start: f.f.Length(), End: f.f.Length()}, nil
}
a := Adr{Start: -ind[1] + start, End: -ind[0] + start}
return a, nil
}
reg, e := regexp.Compile(pa.Reg)
if e != nil {
return Adr{}, e
}
f.f.Seek(int64(start), 0)
ind := reg.FindInputIndex(f.f)
if ind == nil { // No match
return Adr{Start: f.f.Length(), End: f.f.Length()}, nil
}
return Adr{Start: ind[0] + start, End: ind[1] + start}, nil
case padr.PLUS:
la, le := f.evalAdr(*pa.Left, false, start)
if le != nil {
return Adr{}, le
}
la = f.sanitiseAdr(la)
return f.evalAdr(*pa.Right, false, la.End)
case padr.MINUS:
la, le := f.evalAdr(*pa.Left, false, start)
if le != nil {
return Adr{}, le
}
la = f.sanitiseAdr(la)
return f.evalAdr(*pa.Right, true, la.Start)
case padr.COMMA:
la, le := f.evalAdr(*pa.Left, false, start)
if le != nil {
return Adr{}, le
}
ra, re := f.evalAdr(*pa.Right, false, start)
if re != nil {
return Adr{}, re
}
return Adr{Start: la.Start, End: ra.End}, nil
case padr.SEMI:
la, le := f.evalAdr(*pa.Left, false, start)
if le != nil {
return Adr{}, le
}
f.dot = f.sanitiseAdr(la)
ra, re := f.evalAdr(*pa.Right, false, start)
if re != nil {
return Adr{}, re
}
return Adr{Start: la.Start, End: ra.End}, nil
default:
panic("Unkown adr operator")
}
spew.Dump(pa)
return Adr{}, nil
}
// fix is a int that refere to a fixed position in the file, it is returned updated
// to keep track for e.g. extract when it does modification
func (f *File) run(cmd parser.Command, fix int) (fa int, e error) {
var (
adr Adr
reg *regexp.Regexp
)
f.dot = f.sanitiseAdr(f.dot)
// TODO: Update fix locations
switch cmd.Type {
case parser.C_adr: // Set dot command
f.dot, e = f.EvalAdr(cmd.Adr)
case parser.C_a: // Append
f.f.Change(f.dot.End, f.dot.End, []byte(cmd.Text))
if fix >= f.dot.End {
fix += len(cmd.Text)
}
case parser.C_c: // Change
f.f.Change(f.dot.Start, f.dot.End, []byte(cmd.Text))
if fix >= f.dot.End {
fix += len(cmd.Text) - (f.dot.End - f.dot.Start)
} else if fix > f.dot.Start && fix < f.dot.End {
fix = -1 // Fix point not well defined with this change
}
case parser.C_i: // Insert
f.f.Change(f.dot.Start, f.dot.Start, []byte(cmd.Text))
if fix > f.dot.Start {
fix += len(cmd.Text)
}
case parser.C_d: // Delete
f.f.Change(f.dot.Start, f.dot.End, nil)
if fix >= f.dot.End {
fix -= (f.dot.End - f.dot.Start)
} else if fix > f.dot.Start && fix < f.dot.End {
fix = -1 // Fix point not well defined with this change
}
case parser.C_m: // Move
adr, e = f.EvalAdr(cmd.Adr)
if e != nil {
break
}
te, _ := f.f.Get(f.dot.Start, f.dot.End)
f.f.Change(adr.End, adr.End, te)
f.f.Change(f.dot.Start, f.dot.End, nil)
case parser.C_t: // Copy
adr, e = f.EvalAdr(cmd.Adr)
if e != nil {
break
}
te, _ := f.f.Get(f.dot.Start, f.dot.End)
f.f.Change(adr.End, adr.End, te)
case parser.C_s: // Substitute
reg, e = regexp.Compile(cmd.Text) // |Text|Sub|
if e != nil {
break
}
f.f.Seek(int64(f.dot.Start), 0)
loc := reg.FindInputSubmatchIndex(f.f)
if loc == nil {
break
}
for i := range loc {
loc[i] += f.dot.Start
}
t, _ := f.f.Get(loc[0], loc[1])
re := reg.Expand([]byte{}, []byte(cmd.Sub), t, loc)
// Now we have it so now substitute
f.f.Change(loc[0], loc[1], re)
case parser.C_x: // Extract
// TODO: Think about how this should work for after change overlapping etc. ... (need usage to know I think)
// Note that it may create eternal loop, if the user is not carefull... We consider this ok...
// Do a fast path for the common operation of working on every line
if cmd.Text == ".*" {
var fp = f.dot.Start
for n, e := f.f.OffsetBytes([]byte{'\n'}, fp); fp < f.f.Length(); n, e = f.f.OffsetBytes([]byte{'\n'}, fp) {
if e != nil {
panic(e) // Should not happen!
}
fn := File{f: f.f, dot: Adr{Start: fp, End: n}}
if n < 0 {
// Did not find any, consider everything until eof a line
fn = File{f: f.f, dot: Adr{Start: fp, End: f.f.Length()}}
}
fp = n + 1
fp, e = fn.run(cmd.Cmds[0], fp)
if e != nil {
panic(e)
} else if fp < 0 {
e = errors.New("Undefined inner extract change")
}
if n < 0 {
break
}
}
break
}
reg, e = regexp.Compile(cmd.Text)
if e != nil {
break
}
var fp = f.dot.Start
f.f.Seek(int64(fp), 0)
for loc := reg.FindInputIndex(f.f); loc != nil; loc = reg.FindInputIndex(f.f) {
if len(loc) > 1 && loc[0] == loc[1] {
// If we have null match we need to check so we don't keep stamping at the
// same location
if loc[0] == 0 {
//lastloc = -1;
fp++ // We should advance one rune note one byt
_, er := f.f.Seek(int64(fp), 0)
if er != nil { // End of file
break
}
continue
}
}
// Create a new file with dot set and run the provided cmd on that
fn := File{f: f.f, dot: Adr{Start: loc[0] + fp, End: loc[1] + fp}}
fp = fp + loc[1]
fp, e = fn.run(cmd.Cmds[0], fp) // TODO: What if this is nill, loop loop? i.e. Run all subcommands not just one!
if e != nil {
break
} else if fp < 0 {
e = errors.New("Undefined inner extract change")
}
// TODO: Maybe we could return negative fix point to indicate that we had an overlapping edit?
if fp >= f.f.Length() {
break
}
_, er := f.f.Seek(int64(fp), 0)
if er != nil {
break
}
}
case parser.C_y: // Extract between matches
e = errors.New("y not implemented yet")
case parser.C_g: // Guard
reg, e = regexp.Compile(cmd.Text)
if e != nil {
break
}
f.f.Seek(int64(f.dot.Start), 0)
loc := reg.FindInputIndex(f.f)
if loc != nil && loc[1]+f.dot.Start <= f.dot.End {
return f.run(cmd.Cmds[0], fix)
}
case parser.C_v: // Guard not
reg, e = regexp.Compile(cmd.Text)
if e != nil {
break
}
f.f.Seek(int64(f.dot.Start), 0)
loc := reg.FindInputIndex(f.f)
if loc == nil || loc[1]+f.dot.Start > f.dot.End {
return f.run(cmd.Cmds[0], fix)
}
case parser.C_k: // Store dot in adr mark
adrmark = f.dot
default:
return fix, fmt.Errorf("Unkown command %d", cmd.Type)
}
return fix, e
}