package parser
import (
"bytes"
"github.com/gomarkdown/markdown/ast"
)
// citation parses a citation. In its most simple form [@ref], we allow multiple
// being separated by semicolons and a sub reference inside ala pandoc: [@ref, p. 23].
// Each citation can have a modifier: !, ? or - wich mean:
//
// ! - normative
// ? - formative
// - - suppressed
//
// The suffix starts after a comma, we strip any whitespace before and after. If the output
// allows for it, this can be rendered.
func citation(p *Parser, data []byte, offset int) (int, ast.Node) {
// look for the matching closing bracket
i := offset + 1
for level := 1; level > 0 && i < len(data); i++ {
switch {
case data[i] == '\n':
// no newlines allowed.
return 0, nil
case data[i-1] == '\\':
continue
case data[i] == '[':
level++
case data[i] == ']':
level--
if level <= 0 {
i-- // compensate for extra i++ in for loop
}
}
}
if i >= len(data) {
return 0, nil
}
node := &ast.Citation{}
citations := bytes.Split(data[1:i], []byte(";"))
for _, citation := range citations {
var suffix []byte
citation = bytes.TrimSpace(citation)
j := 0
if citation[j] != '@' {
// not a citation, drop out entirely.
return 0, nil
}
if c := bytes.Index(citation, []byte(",")); c > 0 {
part := citation[:c]
suff := citation[c+1:]
part = bytes.TrimSpace(part)
suff = bytes.TrimSpace(suff)
citation = part
suffix = suff
}
citeType := ast.CitationTypeInformative
j = 1
switch citation[j] {
case '!':
citeType = ast.CitationTypeNormative
j++
case '?':
citeType = ast.CitationTypeInformative
j++
case '-':
citeType = ast.CitationTypeSuppressed
j++
}
node.Destination = append(node.Destination, citation[j:])
node.Type = append(node.Type, citeType)
node.Suffix = append(node.Suffix, suffix)
}
return i + 1, node
}