const InteropService_Exporter_Base = require('lib/services/InteropService_Exporter_Base');
const { basename, dirname, friendlySafeFilename } = require('lib/path-utils.js');
const BaseModel = require('lib/BaseModel');
const Folder = require('lib/models/Folder');
const Note = require('lib/models/Note');
const { shim } = require('lib/shim');

class InteropService_Exporter_Md extends InteropService_Exporter_Base {
	async init(destDir) {
		this.destDir_ = destDir;
		this.resourceDir_ = destDir ? `${destDir}/_resources` : null;
		this.createdDirs_ = [];

		await shim.fsDriver().mkdir(this.destDir_);
		await shim.fsDriver().mkdir(this.resourceDir_);
	}

	async makeDirPath_(item, pathPart = null) {
		let output = '';
		while (true) {
			if (item.type_ === BaseModel.TYPE_FOLDER) {
				if (pathPart) {
					output = `${pathPart}/${output}`;
				} else {
					output = `${friendlySafeFilename(item.title, null, true)}/${output}`;
					output = await shim.fsDriver().findUniqueFilename(output);
				}
			}
			if (!item.parent_id) return output;
			item = await Folder.load(item.parent_id);
		}
	}

	async relaceLinkedItemIdsByRelativePaths_(item) {
		const relativePathToRoot = await this.makeDirPath_(item, '..');

		const newBody = await this.replaceResourceIdsByRelativePaths_(item.body, relativePathToRoot);
		return await this.replaceNoteIdsByRelativePaths_(newBody, relativePathToRoot);
	}

	async replaceResourceIdsByRelativePaths_(noteBody, relativePathToRoot) {
		const linkedResourceIds = await Note.linkedResourceIds(noteBody);
		const resourcePaths = this.context() && this.context().resourcePaths ? this.context().resourcePaths : {};

		const createRelativePath = function(resourcePath) {
			return `${relativePathToRoot}_resources/${basename(resourcePath)}`;
		};
		return await this.replaceItemIdsByRelativePaths_(noteBody, linkedResourceIds, resourcePaths, createRelativePath);
	}

	async replaceNoteIdsByRelativePaths_(noteBody, relativePathToRoot) {
		const linkedNoteIds = await Note.linkedNoteIds(noteBody);
		const notePaths = this.context() && this.context().notePaths ? this.context().notePaths : {};

		const createRelativePath = function(notePath) {
			return encodeURI(`${relativePathToRoot}${notePath}`.trim());
		};
		return await this.replaceItemIdsByRelativePaths_(noteBody, linkedNoteIds, notePaths, createRelativePath);
	}

	async replaceItemIdsByRelativePaths_(noteBody, linkedItemIds, paths, fn_createRelativePath) {
		let newBody = noteBody;

		for (let i = 0; i < linkedItemIds.length; i++) {
			const id = linkedItemIds[i];
			const itemPath = fn_createRelativePath(paths[id]);
			newBody = newBody.replace(new RegExp(`:/${id}`, 'g'), itemPath);
		}

		return newBody;
	}

	async prepareForProcessingItemType(type, itemsToExport) {
		if (type === BaseModel.TYPE_NOTE) {
			// Create unique file path for the note
			const context = {
				notePaths: {},
			};
			for (let i = 0; i < itemsToExport.length; i++) {
				const itemType = itemsToExport[i].type;

				if (itemType !== type) continue;

				const itemOrId = itemsToExport[i].itemOrId;
				const note = typeof itemOrId === 'object' ? itemOrId : await Note.load(itemOrId);

				if (!note) continue;

				let notePath = `${await this.makeDirPath_(note)}${friendlySafeFilename(note.title, null, true)}.md`;
				notePath = await shim.fsDriver().findUniqueFilename(`${this.destDir_}/${notePath}`, Object.values(context.notePaths));
				context.notePaths[note.id] = notePath;
			}

			// Strip the absolute path to export dir and keep only the relative paths
			const destDir = this.destDir_;
			Object.keys(context.notePaths).map(function(id) {
				context.notePaths[id] = context.notePaths[id].substr(destDir.length + 1);
			});

			this.updateContext(context);
		}
	}

	async processItem(ItemClass, item) {
		if ([BaseModel.TYPE_NOTE, BaseModel.TYPE_FOLDER].indexOf(item.type_) < 0) return;

		if (item.type_ === BaseModel.TYPE_FOLDER) {
			const dirPath = `${this.destDir_}/${await this.makeDirPath_(item)}`;

			if (this.createdDirs_.indexOf(dirPath) < 0) {
				await shim.fsDriver().mkdir(dirPath);
				this.createdDirs_.push(dirPath);
			}

		} else if (item.type_ === BaseModel.TYPE_NOTE) {
			const notePaths = this.context() && this.context().notePaths ? this.context().notePaths : {};
			const noteFilePath = `${this.destDir_}/${notePaths[item.id]}`;

			const noteBody = await this.relaceLinkedItemIdsByRelativePaths_(item);
			const modNote = Object.assign({}, item, { body: noteBody });
			const noteContent = await Note.serializeForEdit(modNote);
			await shim.fsDriver().mkdir(dirname(noteFilePath));
			await shim.fsDriver().writeFile(noteFilePath, noteContent, 'utf-8');
		}
	}

	async processResource(resource, filePath) {
		const destResourcePath = `${this.resourceDir_}/${basename(filePath)}`;
		await shim.fsDriver().copy(filePath, destResourcePath);
	}

	async close() {}
}

module.exports = InteropService_Exporter_Md;