import {
  CodeBlock,
  Line,
  Node,
  parse,
  Table,
} from "../scrapbox-parser/mod.ts";

export const convert = (text: string): string => {
  const blocks = parse(text, { hasTitle: false });
  return blocks.flatMap((block) => {
    switch (block.type) {
      case "title":
        return [];
      case "codeBlock":
        return convertCodeBlock(block);
      case "table":
        return convertTable(block);
      case "line":
        return convertLine(block);
    }
  })
    .map((line) => line).join("\n");
};

/** コードブロックはそのまま復元する */
const convertCodeBlock = (
  { fileName, content, indent }: CodeBlock,
) => {
  const tag = " ".repeat(indent);

  return [
    `${tag}code:${fileName}`,
    ...content.split("\n").map((line) => `${tag} ${line}`),
  ];
};

/** テーブル中のリンクを外す */
const convertTable = ({ fileName, cells, indent }: Table) => {
  const tag = " ".repeat(indent);

  return [
    `${tag}table:${fileName}`,
    ...cells.map((cell) =>
      `${tag} ${
        cell.map((nodes) => nodes.map((node) => convertNode(node)).join("")).join("\t")
      }`
    ),
  ];
};

/** 行内リンクを外す */
const convertLine = ({ nodes, indent }: Line) => [
  `${" ".repeat(indent)}${
    nodes.map((node) => `${convertNode(node)}`).join(
      "",
    )
  }`,
];

/** リンクを外したnodeを作る */
const convertNode = (node: Node): string => {
  switch (node.type) {
    case "quote":
      return `> ${node.nodes.map((node) => convertNode(node)).join("")}`;
    case "strong":
      return `[[${node.nodes.map((node) => convertNode(node)).join("")}]]`;
    case "decoration": {
      const deco = node.decos.map((deco) => {
        const num = parseInt(deco.match(/\*-(\d)/)?.[1] ?? "0");
        return num > 0 ? "*".repeat(num) : deco;
      }).join("");

      return `[${deco ? `${deco} ` : ""}${
        node.nodes.map((node) => convertNode(node)).join("")
      }]`;
    }
    case "hashTag":
      return node.href;
    // linterのバグで、何故か警告が出る
    // deno-lint-ignore no-fallthrough
    case "link": 
      return node.pathType === "absolute" ? node.raw : node.href;
    default:
      return node.raw;
  }
};