import {
	GET_ALL_ENTRIES,
	GET_ENTRY,
	GET_ENTRIES_FOR_TAG,
	GET_BACKLINKS_FOR_ENTRY,
	GET_OUTLINKS_FOR_ENTRY,
} from "../sql/entries.js"

export default class EntriesService {
	database

	constructor(database) {
		this.database = database
	}

	getEntry = (title) => {
		return this.database.prepare(GET_ENTRY).get(title)
	}

	getAllEntries = (sort, limit) => {
		const entries = this.database.prepare(GET_ALL_ENTRIES).all()

		const sorted =
			sort === "date" ? this._sortByDate(entries) : this._sortByTitle(entries, "title")

		const sliced = sorted.slice(0, Number(limit) || -1)

		return {
			count: sliced.length,
			data: sliced,
		}
	}

	getEntriesForTag = (tag, sort) => {
		const entries = this.database.prepare(GET_ENTRIES_FOR_TAG).all(tag)
		return {
			count: entries.length,
			data:
				sort === "date"
					? this._sortByDate(entries)
					: this._sortByTitle(entries, "entry_title"),
		}
	}

	getBacklinksForEntry = (title) => {
		const backlinks = this.database.prepare(GET_BACKLINKS_FOR_ENTRY).all(title)
		const sorted = this._sortByTitle(backlinks, "source_entry_title")
		const list = sorted.flatMap((i) => i.source_entry_title)
		return {
			count: backlinks.length,
			data: list,
		}
	}

	getOutlinksForEntry = (title) => {
		const outlinks = this.database.prepare(GET_OUTLINKS_FOR_ENTRY).all(title)
		const sorted = this._sortByTitle(outlinks, "target_entry_title")
		const list = sorted.flatMap((i) => i.target_entry_title)
		return {
			count: outlinks.length,
			data: list,
		}
	}

	_sortByTitle = (entries, fieldName) => {
		return entries.sort((a, b) => a[fieldName].localeCompare(b[fieldName]))
	}

	_sortByDate = (entries, fieldName = "last_modified") => {
		const sorted = entries.sort((a, b) => new Date(b[fieldName]) - new Date(a[fieldName]))
		return sorted
	}
}