v/vlib/v/parser/tmpl.v

326 lines
9.5 KiB
V

// Copyright (c) 2019-2022 Alexander Medvednikov. All rights reserved.
// Use of this source code is governed by an MIT license
// that can be found in the LICENSE file.
module parser
import v.token
import v.errors
import os
import strings
enum State {
simple // default - no special interpretation of tags, *at all*!
// That is suitable for the general case of text template interpolation,
// for example for interpolating arbitrary source code (even V source) templates.
//
html // default, only when the template extension is .html
css // <style>
js // <script>
// span // span.{
}
fn (mut state State) update(line string) {
trimmed_line := line.trim_space()
if is_html_open_tag('style', line) {
state = .css
} else if trimmed_line == '</style>' {
state = .html
} else if is_html_open_tag('script', line) {
state = .js
} else if trimmed_line == '</script>' {
state = .html
}
}
const tmpl_str_end = "')\n"
// check HTML open tag `<name attr="x" >`
fn is_html_open_tag(name string, s string) bool {
trimmed_line := s.trim_space()
mut len := trimmed_line.len
if len < name.len {
return false
}
mut sub := trimmed_line[0..1]
if sub != '<' { // not start with '<'
return false
}
sub = trimmed_line[len - 1..len]
if sub != '>' { // not end with '<'
return false
}
sub = trimmed_line[len - 2..len - 1]
if sub == '/' { // self-closing
return false
}
sub = trimmed_line[1..len - 1]
if sub.contains_any('<>') { // `<name <bad> >`
return false
}
if sub == name { // `<name>`
return true
} else {
len = name.len
if sub.len <= len { // `<nam>` or `<meme>`
return false
}
if sub[..len + 1] != '$name ' { // not `<name ...>`
return false
}
return true
}
}
fn insert_template_code(fn_name string, tmpl_str_start string, line string) string {
// HTML, may include `@var`
// escaped by cgen, unless it's a `vweb.RawHtml` string
trailing_bs := parser.tmpl_str_end + 'sb_${fn_name}.write_u8(92)\n' + tmpl_str_start
round1 := ['\\', '\\\\', r"'", "\\'", r'@', r'$']
round2 := [r'$$', r'\@', r'.$', r'.@']
mut rline := line.replace_each(round1).replace_each(round2)
if rline.ends_with('\\') {
rline = rline[0..rline.len - 2] + trailing_bs
}
return rline
}
// compile_file compiles the content of a file by the given path as a template
pub fn (mut p Parser) compile_template_file(template_file string, fn_name string) string {
mut lines := os.read_lines(template_file) or {
p.error('reading from $template_file failed')
return ''
}
basepath := os.dir(template_file)
lstartlength := lines.len * 30
tmpl_str_start := "\tsb_${fn_name}.write_string('"
mut source := strings.new_builder(1000)
source.writeln('
import strings
// === vweb html template ===
fn vweb_tmpl_${fn_name}() string {
mut sb_$fn_name := strings.new_builder($lstartlength)\n
')
source.write_string(tmpl_str_start)
//
mut state := State.simple
template_ext := os.file_ext(template_file)
if template_ext.to_lower() == '.html' {
state = .html
}
//
mut in_span := false
mut end_of_line_pos := 0
mut start_of_line_pos := 0
mut tline_number := -1 // keep the original line numbers, even after insert/delete ops on lines; `i` changes
for i := 0; i < lines.len; i++ {
line := lines[i]
tline_number++
start_of_line_pos = end_of_line_pos
end_of_line_pos += line.len + 1
if state != .simple {
state.update(line)
}
$if trace_tmpl ? {
eprintln('>>> tfile: $template_file, spos: ${start_of_line_pos:6}, epos:${end_of_line_pos:6}, fi: ${tline_number:5}, i: ${i:5}, state: ${state:10}, line: $line')
}
if line.contains('@header') {
position := line.index('@header') or { 0 }
p.error_with_error(errors.Error{
message: "Please use @include 'header' instead of @header (deprecated)"
file_path: template_file
pos: token.Pos{
len: '@header'.len
line_nr: tline_number
pos: start_of_line_pos + position
last_line: lines.len
}
reporter: .parser
})
continue
}
if line.contains('@footer') {
position := line.index('@footer') or { 0 }
p.error_with_error(errors.Error{
message: "Please use @include 'footer' instead of @footer (deprecated)"
file_path: template_file
pos: token.Pos{
len: '@footer'.len
line_nr: tline_number
pos: start_of_line_pos + position
last_line: lines.len
}
reporter: .parser
})
continue
}
if line.contains('@include ') {
lines.delete(i)
mut file_name := line.split("'")[1]
mut file_ext := os.file_ext(file_name)
if file_ext == '' {
file_ext = '.html'
}
file_name = file_name.replace(file_ext, '')
// relative path, starting with the current folder
mut templates_folder := os.real_path(basepath)
if file_name.contains('/') && file_name.starts_with('/') {
// an absolute path
templates_folder = ''
}
file_path := os.real_path(os.join_path_single(templates_folder, '$file_name$file_ext'))
$if trace_tmpl ? {
eprintln('>>> basepath: "$basepath" , template_file: "$template_file" , fn_name: "$fn_name" , @include line: "$line" , file_name: "$file_name" , file_ext: "$file_ext" , templates_folder: "$templates_folder" , file_path: "$file_path"')
}
file_content := os.read_file(file_path) or {
position := line.index('@include ') or { 0 } + '@include '.len
p.error_with_error(errors.Error{
message: 'Reading file $file_name from path: $file_path failed'
details: "Failed to @include '$file_name'"
file_path: template_file
pos: token.Pos{
len: '@include '.len + file_name.len
line_nr: tline_number
pos: start_of_line_pos + position
last_line: lines.len
}
reporter: .parser
})
''
}
file_splitted := file_content.split_into_lines().reverse()
for f in file_splitted {
tline_number--
lines.insert(i, f)
}
i--
continue
}
if line.contains('@if ') {
source.writeln(parser.tmpl_str_end)
pos := line.index('@if') or { continue }
source.writeln('if ' + line[pos + 4..] + '{')
source.writeln(tmpl_str_start)
continue
}
if line.contains('@end') {
// Remove new line byte
source.go_back(1)
source.writeln(parser.tmpl_str_end)
source.writeln('}')
source.writeln(tmpl_str_start)
continue
}
if line.contains('@else') {
// Remove new line byte
source.go_back(1)
source.writeln(parser.tmpl_str_end)
source.writeln(' } else { ')
source.writeln(tmpl_str_start)
continue
}
if line.contains('@for') {
source.writeln(parser.tmpl_str_end)
pos := line.index('@for') or { continue }
source.writeln('for ' + line[pos + 4..] + '{')
source.writeln(tmpl_str_start)
continue
}
if state == .simple {
// by default, just copy 1:1
source.writeln(insert_template_code(fn_name, tmpl_str_start, line))
continue
}
// The .simple mode ends here. The rest handles .html/.css/.js state transitions.
if state != .simple {
if line.contains('@js ') {
pos := line.index('@js') or { continue }
source.write_string('<script src="')
source.write_string(line[pos + 5..line.len - 1])
source.writeln('"></script>')
continue
}
if line.contains('@css ') {
pos := line.index('@css') or { continue }
source.write_string('<link href="')
source.write_string(line[pos + 6..line.len - 1])
source.writeln('" rel="stylesheet" type="text/css">')
continue
}
}
match state {
.html {
line_t := line.trim_space()
if line_t.starts_with('span.') && line.ends_with('{') {
// `span.header {` => `<span class='header'>`
class := line.find_between('span.', '{').trim_space()
source.writeln('<span class="$class">')
in_span = true
continue
} else if line_t.starts_with('.') && line.ends_with('{') {
// `.header {` => `<div class='header'>`
class := line.find_between('.', '{').trim_space()
trimmed := line.trim_space()
source.write_string(strings.repeat(`\t`, line.len - trimmed.len)) // add the necessary indent to keep <div><div><div> code clean
source.writeln('<div class="$class">')
continue
} else if line_t.starts_with('#') && line.ends_with('{') {
// `#header {` => `<div id='header'>`
class := line.find_between('#', '{').trim_space()
source.writeln('<div id="$class">')
continue
} else if line_t == '}' {
source.write_string(strings.repeat(`\t`, line.len - line_t.len)) // add the necessary indent to keep <div><div><div> code clean
if in_span {
source.writeln('</span>')
in_span = false
} else {
source.writeln('</div>')
}
continue
}
}
.js {
// if line.contains('//V_TEMPLATE') {
source.writeln(insert_template_code(fn_name, tmpl_str_start, line))
//} else {
// replace `$` to `\$` at first to escape JavaScript template literal syntax
// source.writeln(line.replace(r'$', r'\$').replace(r'$$', r'@').replace(r'.$',
// r'.@').replace(r"'", r"\'"))
//}
continue
}
.css {
// disable template variable declaration in inline stylesheet
// because of some CSS rules prefixed with `@`.
source.writeln(line.replace(r'.$', r'.@').replace(r"'", r"\'"))
continue
}
else {}
}
// by default, just copy 1:1
source.writeln(insert_template_code(fn_name, tmpl_str_start, line))
}
source.writeln(parser.tmpl_str_end)
source.writeln('\t_tmpl_res_$fn_name := sb_${fn_name}.str() ')
source.writeln('\treturn _tmpl_res_$fn_name')
source.writeln('}')
source.writeln('// === end of vweb html template_file: $template_file ===')
result := source.str()
$if trace_tmpl_expansion ? {
eprintln('>>>>>>> template expanded to:')
eprintln(result)
eprintln('-----------------------------')
}
return result
}