import {
    isDataObject,
    ISdtfReadableContentComponent,
    ISdtfWriteableAttribute,
    SdtfError,
} from '@shapediver/sdk.sdtf-core';
import { ISdtfReadableComponentList } from '../reader/ISdtfReadableComponentList';
import { ISdtfComponentValidator } from '../validation/ISdtfComponentValidator';
import { SdtfComponentValidator } from '../validation/SdtfComponentValidator';
import { ISdtfWriteableComponentList } from '../writer/ISdtfWriteableComponentList';
import { ISdtfComponentFactory } from './ISdtfComponentFactory';
import { ISdtfComponentList, ISdtfPartialComponentList } from './ISdtfComponentList';
import { SdtfComponentFactory } from './SdtfComponentFactory';

export class SdtfComponentFactoryWrapper implements SdtfComponentFactoryWrapper {
    private readonly factory: ISdtfComponentFactory;

    constructor() {
        this.factory = new SdtfComponentFactory();
    }

    createFromJson(json: Record<string, unknown>): ISdtfComponentList {
        const f = this.factory; // Alias to shorten lines
        return this.createComponentList({
            accessors: this.buildFromArray(
                json,
                f.propertyNameAccessors,
                f.createAccessor.bind(f)
            ),
            asset: this.buildFromObject(json, '', f.createAsset.bind(f)),
            attributes: this.buildFromArray(
                json,
                f.propertyNameAttributes,
                f.createAttributes.bind(f)
            ),
            buffers: this.buildFromArray(json, f.propertyNameBuffers, f.createBuffer.bind(f)),
            bufferViews: this.buildFromArray(
                json,
                f.propertyNameBufferViews,
                f.createBufferView.bind(f)
            ),
            chunks: this.buildFromArray(json, f.propertyNameChunks, f.createChunk.bind(f)),
            items: this.buildFromArray(json, f.propertyNameDataItems, f.createDataItem.bind(f)),
            fileInfo: this.buildFromObject(json, f.propertyNameFileInfo, f.createFileInfo.bind(f)),
            nodes: this.buildFromArray(json, f.propertyNameNodes, f.createNode.bind(f)),
            typeHints: this.buildFromArray(
                json,
                f.propertyNameTypeHints,
                f.createTypeHint.bind(f)
            ),
        });
    }

    createFromReadable(readableComponents: ISdtfReadableComponentList): ISdtfComponentList {
        const f = this.factory; // Alias to shorten lines
        const partialComponentList: ISdtfPartialComponentList = {
            accessors: readableComponents.accessors.map((a) => f.createAccessor(a.toDataObject())),
            asset: f.createAsset(readableComponents.asset.toDataObject()),
            attributes: readableComponents.attributes.map((a) =>
                f.createAttributes(a.toDataObject())
            ),
            buffers: readableComponents.buffers.map((b) => f.createBuffer(b.toDataObject())),
            bufferViews: readableComponents.bufferViews.map((b) =>
                f.createBufferView(b.toDataObject())
            ),
            chunks: readableComponents.chunks.map((c) => f.createChunk(c.toDataObject())),
            items: readableComponents.items.map((i) => f.createDataItem(i.toDataObject())),
            fileInfo: f.createFileInfo(readableComponents.fileInfo.toDataObject()),
            nodes: readableComponents.nodes.map((n) => f.createNode(n.toDataObject())),
            typeHints: readableComponents.typeHints.map((y) => f.createTypeHint(y.toDataObject())),
        };

        this.mapHierarchyRepresentation(partialComponentList, readableComponents);
        return this.createComponentList(partialComponentList);
    }

    createFromWriteable(writeableComponents: ISdtfWriteableComponentList): ISdtfComponentList {
        const f = this.factory; // Alias to shorten lines
        const partialComponentList: ISdtfPartialComponentList = {
            accessors: writeableComponents.accessors.map((a) =>
                f.createAccessor(a.toDataObject())
            ),
            asset: f.createAsset(writeableComponents.asset.toDataObject()),
            attributes: writeableComponents.attributes.map((a) =>
                f.createAttributes(a.toDataObject())
            ),
            buffers: writeableComponents.buffers.map((b) => f.createBuffer(b.toDataObject())),
            bufferViews: writeableComponents.bufferViews.map((b) =>
                f.createBufferView(b.toDataObject())
            ),
            chunks: writeableComponents.chunks.map((c) => f.createChunk(c.toDataObject())),
            items: writeableComponents.items.map((i) => f.createDataItem(i.toDataObject())),
            fileInfo: f.createFileInfo(writeableComponents.fileInfo.toDataObject()),
            nodes: writeableComponents.nodes.map((n) => f.createNode(n.toDataObject())),
            typeHints: writeableComponents.typeHints.map((t) =>
                f.createTypeHint(t.toDataObject())
            ),
            // The writeable-optimizer merges all buffers, thus there is only a single binary buffer
            binaryBody: writeableComponents.buffers.find((buffer) => !buffer.uri)?.data,
        };

        this.mapHierarchyRepresentation(partialComponentList, writeableComponents);
        return this.createComponentList(partialComponentList);
    }

    /**
     * Validates every partial-component and returns a corresponding component list.
     * @private
     * @throws {@link SdtfError} when a partial-component is invalid.
     */
    createComponentList(partialComponents: ISdtfPartialComponentList): ISdtfComponentList {
        const validator: ISdtfComponentValidator = new SdtfComponentValidator(partialComponents);

        // NOTE the validation order is important here!
        const asset = partialComponents.asset;
        validator.validateAsset(asset);

        const fileInfo = partialComponents.fileInfo;
        validator.validateFileInfo(fileInfo);

        const buffers = partialComponents.buffers.map((b) => {
            validator.validateBuffer(b);
            return b;
        });
        const bufferViews = partialComponents.bufferViews.map((b) => {
            validator.validateBufferView(b);
            return b;
        });
        const accessors = partialComponents.accessors.map((a) => {
            validator.validateAccessor(a);
            return a;
        });
        const typeHints = partialComponents.typeHints.map((t) => {
            validator.validateTypeHint(t);
            return t;
        });
        const attributes = partialComponents.attributes.map((a) => {
            validator.validateAttributes(a);
            return a;
        });
        const chunks = partialComponents.chunks.map((c) => {
            validator.validateChunk(c);
            return c;
        });
        const dataItems = partialComponents.items.map((d) => {
            validator.validateDataItem(d);
            return d;
        });
        const nodes = partialComponents.nodes.map((n) => {
            validator.validateNode(n);
            return n;
        });

        return {
            accessors,
            asset,
            attributes,
            buffers,
            bufferViews,
            chunks,
            items: dataItems,
            nodes,
            typeHints,
            fileInfo,
            binaryBody: partialComponents.binaryBody,
        };
    }

    /**
     * Validation wrapper around the given create function for a content object of the specified name.
     * @private
     * @throws {@link SdtfError} when something goes wrong.
     */
    buildFromObject<T>(
        jsonObject: Record<string, unknown>,
        propertyName: string,
        createFn: (data: Record<string, unknown>) => T
    ): T {
        const componentDataObject = propertyName ? jsonObject[propertyName] : jsonObject;
        if (!isDataObject(componentDataObject))
            throw new SdtfError(`Invalid item at ${propertyName}: Item must be an object.`);
        return createFn(componentDataObject);
    }

    /**
     * Validation wrapper around the given create function for a content array of the specified name.
     * @private
     * @throws {@link SdtfError} when something goes wrong.
     */
    buildFromArray<T>(
        jsonArray: Record<string, unknown>,
        propertyName: string,
        createFn: (data: Record<string, unknown>) => T
    ): T[] {
        const componentDataArray = jsonArray[propertyName];
        if (componentDataArray === undefined) return [];
        if (!Array.isArray(componentDataArray))
            throw new SdtfError(`Invalid content property: '${propertyName}' must be an array.`);

        return componentDataArray.map((componentDataItem: unknown, i) => {
            if (!isDataObject(componentDataItem))
                throw new SdtfError(
                    `Invalid item at ${propertyName}[${i}]: Item must be an object.`
                );
            return createFn(componentDataItem);
        });
    }

    /**
     * Readable and writeable components use object references to represent the hierarchy.
     * However, sdTF components use reference IDs for this.
     * This method maps the object representation into a reference ID representation.
     * @private
     */
    mapHierarchyRepresentation(
        target: ISdtfPartialComponentList,
        src: ISdtfWriteableComponentList | ISdtfReadableComponentList
    ): void {
        // Helper to find the element position in an array
        const getIndex = (list: { componentId: string }[], componentId?: string) => {
            if (!componentId) return -1;
            return list.findIndex((c) => c.componentId === componentId);
        };

        target.asset.fileInfo = 0;

        target.accessors.forEach((accessor, index) => {
            const srcComponent = src.accessors[index];
            accessor.bufferView = getIndex(src.bufferViews, srcComponent?.bufferView?.componentId);
        });
        target.attributes.forEach((attributes, index) => {
            if (!attributes.entries) return;
            Object.entries(attributes.entries).forEach(([name, attribute]) => {
                const srcComponent: ISdtfWriteableAttribute | ISdtfReadableContentComponent =
                    src.attributes[index].entries[name];
                if (srcComponent.accessor)
                    attribute.accessor = getIndex(
                        src.accessors,
                        srcComponent?.accessor?.componentId
                    );
                if (srcComponent.typeHint)
                    attribute.typeHint = getIndex(
                        src.typeHints,
                        srcComponent?.typeHint?.componentId
                    );
            });
        });
        target.bufferViews.forEach((bufferView, index) => {
            const srcComponent = src.bufferViews[index];
            bufferView.buffer = getIndex(src.buffers, srcComponent?.buffer?.componentId);
        });
        target.chunks.forEach((chunk, index) => {
            const srcComponent = src.chunks[index];
            if (srcComponent.attributes)
                chunk.attributes = getIndex(src.attributes, srcComponent?.attributes?.componentId);
            chunk.items = srcComponent.items.map((item) => getIndex(src.items, item?.componentId));
            chunk.nodes = srcComponent.nodes.map((node) => getIndex(src.nodes, node?.componentId));
            if (srcComponent.typeHint)
                chunk.typeHint = getIndex(src.typeHints, srcComponent?.typeHint?.componentId);
        });
        target.items.forEach((dataItem, index) => {
            const srcComponent = src.items[index];
            if (srcComponent.accessor)
                dataItem.accessor = getIndex(src.accessors, srcComponent?.accessor?.componentId);
            if (srcComponent.attributes)
                dataItem.attributes = getIndex(
                    src.attributes,
                    srcComponent?.attributes?.componentId
                );
            if (srcComponent.typeHint)
                dataItem.typeHint = getIndex(src.typeHints, srcComponent?.typeHint?.componentId);
        });
        target.nodes.forEach((node, index) => {
            const srcComponent = src.nodes[index];
            if (srcComponent.attributes)
                node.attributes = getIndex(src.attributes, srcComponent?.attributes?.componentId);
            node.items = srcComponent.items.map((item) => getIndex(src.items, item?.componentId));
            node.nodes = srcComponent.nodes.map((node) => getIndex(src.nodes, node?.componentId));
            if (srcComponent.typeHint)
                node.typeHint = getIndex(src.typeHints, srcComponent?.typeHint?.componentId);
        });
    }
}