docx-js/src/patcher/from-docx.ts

import JSZip from "jszip";
import { Element, js2xml } from "xml-js";

import { ImageReplacer } from "@export/packer/image-replacer";
import { IViewWrapper } from "@file/document-wrapper";
import { File } from "@file/file";
import { FileChild } from "@file/file-child";
import { IMediaData, Media } from "@file/media";
import { ConcreteHyperlink, ExternalHyperlink, ParagraphChild } from "@file/paragraph";
import { TargetModeType } from "@file/relationships/relationship/relationship";
import { IContext } from "@file/xml-components";
import { uniqueId } from "@util/convenience-functions";

import { appendContentType } from "./content-types-manager";
import { appendRelationship, getNextRelationshipIndex } from "./relationship-manager";
import { replacer } from "./replacer";
import { toJson } from "./util";

// eslint-disable-next-line functional/prefer-readonly-type
export type InputDataType = Buffer | string | number[] | Uint8Array | ArrayBuffer | Blob | NodeJS.ReadableStream;

export const PatchType = {
    DOCUMENT: "file",
    PARAGRAPH: "paragraph",
} as const;

type ParagraphPatch = {
    readonly type: typeof PatchType.PARAGRAPH;
    readonly children: readonly ParagraphChild[];
};

type FilePatch = {
    readonly type: typeof PatchType.DOCUMENT;
    readonly children: readonly FileChild[];
};

type IImageRelationshipAddition = {
    readonly key: string;
    readonly mediaDatas: readonly IMediaData[];
};

type IHyperlinkRelationshipAddition = {
    readonly key: string;
    readonly hyperlink: { readonly id: string; readonly link: string };
};

export type IPatch = ParagraphPatch | FilePatch;

// From JSZip
type OutputByType = {
    readonly base64: string;
    // eslint-disable-next-line id-denylist
    readonly string: string;
    readonly text: string;
    readonly binarystring: string;
    readonly array: readonly number[];
    readonly uint8array: Uint8Array;
    readonly arraybuffer: ArrayBuffer;
    readonly blob: Blob;
    readonly nodebuffer: Buffer;
};

export type PatchDocumentOutputType = keyof OutputByType;

export type PatchDocumentOptions<T extends PatchDocumentOutputType = PatchDocumentOutputType> = {
    readonly outputType: T;
    readonly data: InputDataType;
    readonly patches: Readonly<Record<string, IPatch>>;
    readonly keepOriginalStyles?: boolean;
};

const imageReplacer = new ImageReplacer();

export const patchDocument = async <T extends PatchDocumentOutputType = PatchDocumentOutputType>({
    outputType,
    data,
    patches,
    keepOriginalStyles,
}: PatchDocumentOptions<T>): Promise<OutputByType[T]> => {
    const zipContent = await JSZip.loadAsync(data);
    const contexts = new Map<string, IContext>();
    const file = {
        Media: new Media(),
    } as unknown as File;

    const map = new Map<string, Element>();

    // eslint-disable-next-line functional/prefer-readonly-type
    const imageRelationshipAdditions: IImageRelationshipAddition[] = [];
    // eslint-disable-next-line functional/prefer-readonly-type
    const hyperlinkRelationshipAdditions: IHyperlinkRelationshipAddition[] = [];
    let hasMedia = false;

    const binaryContentMap = new Map<string, Uint8Array>();

    for (const [key, value] of Object.entries(zipContent.files)) {
        if (!key.endsWith(".xml") && !key.endsWith(".rels")) {
            binaryContentMap.set(key, await value.async("uint8array"));
            continue;
        }

        const json = toJson(await value.async("text"));
        if (key.startsWith("word/") && !key.endsWith(".xml.rels")) {
            const context: IContext = {
                file,
                viewWrapper: {
                    Relationships: {
                        createRelationship: (
                            linkId: string,
                            _: string,
                            target: string,
                            __: (typeof TargetModeType)[keyof typeof TargetModeType],
                        ) => {
                            // eslint-disable-next-line functional/immutable-data
                            hyperlinkRelationshipAdditions.push({
                                key,
                                hyperlink: {
                                    id: linkId,
                                    link: target,
                                },
                            });
                        },
                    },
                } as unknown as IViewWrapper,
                stack: [],
            };
            contexts.set(key, context);

            for (const [patchKey, patchValue] of Object.entries(patches)) {
                const patchText = `{{${patchKey}}}`;
                // TODO: mutates json. Make it immutable
                // We need to loop through to catch every occurrence of the patch text
                // It is possible that the patch text is in the same run
                // This algorithm is limited to one patch per text run
                // Once it cannot find any more occurrences, it will throw an error, and then we break out of the loop
                // https://github.com/dolanmiu/docx/issues/2267
                while (true) {
                    try {
                        replacer({
                            json,
                            patch: {
                                ...patchValue,
                                children: patchValue.children.map((element) => {
                                    // We need to replace external hyperlinks with concrete hyperlinks
                                    if (element instanceof ExternalHyperlink) {
                                        const concreteHyperlink = new ConcreteHyperlink(element.options.children, uniqueId());
                                        // eslint-disable-next-line functional/immutable-data
                                        hyperlinkRelationshipAdditions.push({
                                            key,
                                            hyperlink: {
                                                id: concreteHyperlink.linkId,
                                                link: element.options.link,
                                            },
                                        });
                                        return concreteHyperlink;
                                    } else {
                                        return element;
                                    }
                                }),
                                // eslint-disable-next-line @typescript-eslint/no-explicit-any
                            } as any,
                            patchText,
                            context,
                            keepOriginalStyles,
                        });
                    } catch {
                        break;
                    }
                }
            }

            const mediaDatas = imageReplacer.getMediaData(JSON.stringify(json), context.file.Media);
            if (mediaDatas.length > 0) {
                hasMedia = true;
                // eslint-disable-next-line functional/immutable-data
                imageRelationshipAdditions.push({
                    key,
                    mediaDatas,
                });
            }
        }

        map.set(key, json);
    }

    for (const { key, mediaDatas } of imageRelationshipAdditions) {
        // eslint-disable-next-line functional/immutable-data
        const relationshipKey = `word/_rels/${key.split("/").pop()}.rels`;
        const relationshipsJson = map.get(relationshipKey) ?? createRelationshipFile();
        map.set(relationshipKey, relationshipsJson);

        const index = getNextRelationshipIndex(relationshipsJson);
        const newJson = imageReplacer.replace(JSON.stringify(map.get(key)), mediaDatas, index);
        map.set(key, JSON.parse(newJson) as Element);

        for (let i = 0; i < mediaDatas.length; i++) {
            const { fileName } = mediaDatas[i];
            appendRelationship(
                relationshipsJson,
                index + i,
                "http://schemas.openxmlformats.org/officeDocument/2006/relationships/image",
                `media/${fileName}`,
            );
        }
    }

    for (const { key, hyperlink } of hyperlinkRelationshipAdditions) {
        // eslint-disable-next-line functional/immutable-data
        const relationshipKey = `word/_rels/${key.split("/").pop()}.rels`;

        const relationshipsJson = map.get(relationshipKey) ?? createRelationshipFile();
        map.set(relationshipKey, relationshipsJson);

        appendRelationship(
            relationshipsJson,
            hyperlink.id,
            "http://schemas.openxmlformats.org/officeDocument/2006/relationships/hyperlink",
            hyperlink.link,
            TargetModeType.EXTERNAL,
        );
    }

    if (hasMedia) {
        const contentTypesJson = map.get("[Content_Types].xml");

        if (!contentTypesJson) {
            throw new Error("Could not find content types file");
        }

        appendContentType(contentTypesJson, "image/png", "png");
        appendContentType(contentTypesJson, "image/jpeg", "jpeg");
        appendContentType(contentTypesJson, "image/jpeg", "jpg");
        appendContentType(contentTypesJson, "image/bmp", "bmp");
        appendContentType(contentTypesJson, "image/gif", "gif");
        appendContentType(contentTypesJson, "image/svg+xml", "svg");
    }

    const zip = new JSZip();

    for (const [key, value] of map) {
        const output = toXml(value);

        zip.file(key, output);
    }

    for (const [key, value] of binaryContentMap) {
        zip.file(key, value);
    }

    for (const { data: stream, fileName } of file.Media.Array) {
        zip.file(`word/media/${fileName}`, stream);
    }

    return zip.generateAsync({
        type: outputType,
        mimeType: "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
        compression: "DEFLATE",
    });
};

const toXml = (jsonObj: Element): string => {
    const output = js2xml(jsonObj);
    return output;
};

const createRelationshipFile = (): Element => ({
    declaration: {
        attributes: {
            version: "1.0",
            encoding: "UTF-8",
            standalone: "yes",
        },
    },
    elements: [
        {
            type: "element",
            name: "Relationships",
            attributes: {
                xmlns: "http://schemas.openxmlformats.org/package/2006/relationships",
            },
            elements: [],
        },
    ],
});