Files
outline/shared/editor/rules/mark.ts
2022-01-19 18:43:15 -08:00

157 lines
4.0 KiB
TypeScript

// Adapted from:
// https://github.com/markdown-it/markdown-it-mark/blob/master/index.js
import MarkdownIt from "markdown-it";
import StateInline from "markdown-it/lib/rules_inline/state_inline";
export default function (options: { delim: string; mark: string }) {
const delimCharCode = options.delim.charCodeAt(0);
return function emphasisPlugin(md: MarkdownIt) {
function tokenize(state: StateInline, silent: boolean) {
let i, token;
const start = state.pos,
marker = state.src.charCodeAt(start);
if (silent) {
return false;
}
if (marker !== delimCharCode) {
return false;
}
const scanned = state.scanDelims(state.pos, true);
const ch = String.fromCharCode(marker);
let len = scanned.length;
if (len < 2) {
return false;
}
if (len % 2) {
token = state.push("text", "", 0);
token.content = ch;
len--;
}
for (i = 0; i < len; i += 2) {
token = state.push("text", "", 0);
token.content = ch + ch;
if (!scanned.can_open && !scanned.can_close) {
continue;
}
state.delimiters.push({
marker,
length: 0, // disable "rule of 3" length checks meant for emphasis
jump: i,
token: state.tokens.length - 1,
end: -1,
open: scanned.can_open,
close: scanned.can_close,
});
}
state.pos += scanned.length;
return true;
}
// Walk through delimiter list and replace text tokens with tags
//
function postProcess(
state: StateInline,
delimiters: StateInline.Delimiter[]
) {
let i = 0,
j,
startDelim,
endDelim,
token;
const loneMarkers: number[] = [],
max = delimiters.length;
for (i = 0; i < max; i++) {
startDelim = delimiters[i];
if (startDelim.marker !== delimCharCode) {
continue;
}
if (startDelim.end === -1) {
continue;
}
endDelim = delimiters[startDelim.end];
token = state.tokens[startDelim.token];
token.type = `${options.mark}_open`;
token.tag = "span";
token.attrs = [["class", options.mark]];
token.nesting = 1;
token.markup = options.delim;
token.content = "";
token = state.tokens[endDelim.token];
token.type = `${options.mark}_close`;
token.tag = "span";
token.nesting = -1;
token.markup = options.delim;
token.content = "";
if (
state.tokens[endDelim.token - 1].type === "text" &&
state.tokens[endDelim.token - 1].content === options.delim[0]
) {
loneMarkers.push(endDelim.token - 1);
}
}
// If a marker sequence has an odd number of characters, it's split
// like this: `~~~~~` -> `~` + `~~` + `~~`, leaving one marker at the
// start of the sequence.
//
// So, we have to move all those markers after subsequent s_close tags.
while (loneMarkers.length) {
i = loneMarkers.pop() as number;
j = i + 1;
while (
j < state.tokens.length &&
state.tokens[j].type === `${options.mark}_close`
) {
j++;
}
j--;
if (i !== j) {
token = state.tokens[j];
state.tokens[j] = state.tokens[i];
state.tokens[i] = token;
}
}
}
md.inline.ruler.before("emphasis", options.mark, tokenize);
md.inline.ruler2.before("emphasis", options.mark, function (state) {
let curr;
const tokensMeta = state.tokens_meta,
max = (state.tokens_meta || []).length;
postProcess(state, state.delimiters);
for (curr = 0; curr < max; curr++) {
const delimiters = tokensMeta[curr]?.delimiters;
if (tokensMeta[curr] && delimiters) {
postProcess(state, delimiters);
}
}
return false;
});
};
}