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import { isSpace, normalizeReference } from '../common/utils.mjs'
export default function reference (state, startLine, _endLine, silent) {
let lines = 0
let pos = state.bMarks[startLine] + state.tShift[startLine]
let max = state.eMarks[startLine]
let nextLine = startLine + 1
// if it's indented more than 3 spaces, it should be a code block
if (state.sCount[startLine] - state.blkIndent >= 4) { return false }
if (state.src.charCodeAt(pos) !== 0x5B/* [ */) { return false }
// Simple check to quickly interrupt scan on [link](url) at the start of line.
// Can be useful on practice: https://github.com/markdown-it/markdown-it/issues/54
while (++pos < max) {
if (state.src.charCodeAt(pos) === 0x5D /* ] */ &&
state.src.charCodeAt(pos - 1) !== 0x5C/* \ */) {
if (pos + 1 === max) { return false }
if (state.src.charCodeAt(pos + 1) !== 0x3A/* : */) { return false }
break
}
}
const endLine = state.lineMax
// jump line-by-line until empty one or EOF
const terminatorRules = state.md.block.ruler.getRules('reference')
const oldParentType = state.parentType
state.parentType = 'reference'
for (; nextLine < endLine && !state.isEmpty(nextLine); nextLine++) {
// this would be a code block normally, but after paragraph
// it's considered a lazy continuation regardless of what's there
if (state.sCount[nextLine] - state.blkIndent > 3) { continue }
// quirk for blockquotes, this line should already be checked by that rule
if (state.sCount[nextLine] < 0) { continue }
// Some tags can terminate paragraph without empty line.
let terminate = false
for (let i = 0, l = terminatorRules.length; i < l; i++) {
if (terminatorRules[i](state, nextLine, endLine, true)) {
terminate = true
break
}
}
if (terminate) { break }
}
const str = state.getLines(startLine, nextLine, state.blkIndent, false).trim()
max = str.length
let labelEnd = -1
for (pos = 1; pos < max; pos++) {
const ch = str.charCodeAt(pos)
if (ch === 0x5B /* [ */) {
return false
} else if (ch === 0x5D /* ] */) {
labelEnd = pos
break
} else if (ch === 0x0A /* \n */) {
lines++
} else if (ch === 0x5C /* \ */) {
pos++
if (pos < max && str.charCodeAt(pos) === 0x0A) {
lines++
}
}
}
if (labelEnd < 0 || str.charCodeAt(labelEnd + 1) !== 0x3A/* : */) { return false }
// [label]: destination 'title'
// ^^^ skip optional whitespace here
for (pos = labelEnd + 2; pos < max; pos++) {
const ch = str.charCodeAt(pos)
if (ch === 0x0A) {
lines++
} else if (isSpace(ch)) {
/* eslint no-empty:0 */
} else {
break
}
}
// [label]: destination 'title'
// ^^^^^^^^^^^ parse this
const destRes = state.md.helpers.parseLinkDestination(str, pos, max)
if (!destRes.ok) { return false }
const href = state.md.normalizeLink(destRes.str)
if (!state.md.validateLink(href)) { return false }
pos = destRes.pos
lines += destRes.lines
// save cursor state, we could require to rollback later
const destEndPos = pos
const destEndLineNo = lines
// [label]: destination 'title'
// ^^^ skipping those spaces
const start = pos
for (; pos < max; pos++) {
const ch = str.charCodeAt(pos)
if (ch === 0x0A) {
lines++
} else if (isSpace(ch)) {
/* eslint no-empty:0 */
} else {
break
}
}
// [label]: destination 'title'
// ^^^^^^^ parse this
const titleRes = state.md.helpers.parseLinkTitle(str, pos, max)
let title
if (pos < max && start !== pos && titleRes.ok) {
title = titleRes.str
pos = titleRes.pos
lines += titleRes.lines
} else {
title = ''
pos = destEndPos
lines = destEndLineNo
}
// skip trailing spaces until the rest of the line
while (pos < max) {
const ch = str.charCodeAt(pos)
if (!isSpace(ch)) { break }
pos++
}
if (pos < max && str.charCodeAt(pos) !== 0x0A) {
if (title) {
// garbage at the end of the line after title,
// but it could still be a valid reference if we roll back
title = ''
pos = destEndPos
lines = destEndLineNo
while (pos < max) {
const ch = str.charCodeAt(pos)
if (!isSpace(ch)) { break }
pos++
}
}
}
if (pos < max && str.charCodeAt(pos) !== 0x0A) {
// garbage at the end of the line
return false
}
const label = normalizeReference(str.slice(1, labelEnd))
if (!label) {
// CommonMark 0.20 disallows empty labels
return false
}
// Reference can not terminate anything. This check is for safety only.
/* istanbul ignore if */
if (silent) { return true }
if (typeof state.env.references === 'undefined') {
state.env.references = {}
}
if (typeof state.env.references[label] === 'undefined') {
state.env.references[label] = { title, href }
}
state.parentType = oldParentType
state.line = startLine + lines + 1
return true
}