import { isNumber, sizeNumber } from '$lib/helpers/leaderboard';
import type { DetailsDataset } from '$lib/types/details-data';
import type {
	BenchmarkCard,
	BenchmarkFamilyLanguage,
	BenchmarkRankingRow,
	DetailMetric,
	DetailsLanguageFilter,
	MatrixGroup,
	MatrixDataset,
	MatrixSortDirection,
	ModelGroupRow,
	ModelSort,
	ModelTypeFilter,
	RadarPoint,
	SizeFilter
} from '$lib/types/details';
import type { DetailsDatasetMatrixCell } from '$lib/types/details-data';
import type { LocalizedString } from '$lib/types/i18n';
import type { GroupScore, GuardModel } from '$lib/types/leaderboard';

type SupportedLocale = keyof LocalizedString;
type BenchmarkLeaderMetric = NonNullable<BenchmarkCard['leader']>['metric'];

function localized(value: LocalizedString | null, locale: SupportedLocale, fallback: string) {
	return value?.[locale] ?? value?.en ?? fallback;
}

export function groupMatchesLanguage(dataset: MatrixDataset, language: DetailsLanguageFilter) {
	if (language === 'any') return true;
	return dataset.language === language;
}

export function visibleDetailMatrixDatasets(
	detailMatrixDatasets: readonly MatrixDataset[],
	selectedGroups: readonly string[],
	language: DetailsLanguageFilter
) {
	return detailMatrixDatasets.filter((dataset) => {
		if (!selectedGroups.includes(dataset.sourceGroup)) return false;
		return groupMatchesLanguage(dataset, language);
	});
}

export function buildMatrixGroups(datasets: readonly MatrixDataset[]) {
	const groups: Array<{ key: string; label: string; datasets: MatrixDataset[] }> = [];

	for (const dataset of datasets) {
		const group = groups.find((item) => item.key === dataset.group);
		if (group) {
			group.datasets.push(dataset);
			continue;
		}

		groups.push({
			key: dataset.group,
			label: dataset.group,
			datasets: [dataset]
		});
	}

	return groups;
}

export function detailMetricValue(
	group: GroupScore | DetailsDatasetMatrixCell | undefined,
	metric: DetailMetric
) {
	if (!group) return null;
	if (metric === 'score') return group.score;
	if (metric === 'f1') return group.f1 ?? group.score;
	if (metric === 'recall') {
		if ('recall' in group && group.recall !== undefined) return group.recall;
		return isNumber(group.fnr) ? 1 - group.fnr : null;
	}
	if (metric === 'precision') {
		return 'precision' in group ? (group.precision ?? null) : null;
	}
	if (metric === 'accuracy') {
		return 'accuracy' in group ? (group.accuracy ?? null) : null;
	}
	return group[metric];
}

export function matrixDatasetLabel(dataset: MatrixDataset) {
	return dataset.label;
}

function modelKey(model: GuardModel) {
	return model.modelId ?? model.name;
}

function csvCell(value: string | number | null | undefined) {
	return `"${String(value ?? '').replaceAll('"', '""')}"`;
}

function csvNumber(value: number | null | undefined, digits = 4) {
	return isNumber(value) ? value.toFixed(digits) : '';
}

export function matrixCellValue(
	model: GuardModel,
	dataset: MatrixDataset,
	metric: DetailMetric,
	datasetCells: Record<string, Record<string, DetailsDatasetMatrixCell>>
) {
	const cell = datasetCells[modelKey(model)]?.[dataset.id];
	return detailMetricValue(cell, metric);
}

export function detailMetricSortPolarity(metric: DetailMetric) {
	return metric === 'fpr' || metric === 'fnr' ? -1 : 1;
}

export function sortMatrixRows(
	rows: readonly GuardModel[],
	metric: DetailMetric,
	sortDatasetName: string | null,
	sortDirection: MatrixSortDirection,
	detailMatrixDatasets: readonly MatrixDataset[],
	datasetCells: Record<string, Record<string, DetailsDatasetMatrixCell>>
) {
	const sorted = [...rows];
	const sortDataset = sortDatasetName
		? detailMatrixDatasets.find((dataset) => dataset.name === sortDatasetName)
		: null;

	if (!sortDataset) {
		return sorted.sort((a, b) =>
			sortDirection === -1 ? b.integral - a.integral : a.integral - b.integral
		);
	}

	const polarity = detailMetricSortPolarity(metric);
	return sorted.sort((a, b) => {
		const aValue = matrixCellValue(a, sortDataset, metric, datasetCells);
		const bValue = matrixCellValue(b, sortDataset, metric, datasetCells);
		const aEmpty = !isNumber(aValue);
		const bEmpty = !isNumber(bValue);
		if (aEmpty && bEmpty) return 0;
		if (aEmpty) return 1;
		if (bEmpty) return -1;

		const comparison = ((bValue ?? 0) - (aValue ?? 0)) * polarity;
		return sortDirection === -1 ? comparison : -comparison;
	});
}

export function buildMatrixRows(
	search: string,
	metric: DetailMetric,
	sortDatasetName: string | null,
	sortDirection: MatrixSortDirection,
	sourceModels: readonly GuardModel[],
	detailMatrixDatasets: readonly MatrixDataset[],
	datasetCells: Record<string, Record<string, DetailsDatasetMatrixCell>>
) {
	const normalizedSearch = search.trim().toLowerCase();
	const rows = normalizedSearch
		? sourceModels.filter((model) =>
				[model.short, model.name, model.family, model.org]
					.join(' ')
					.toLowerCase()
					.includes(normalizedSearch)
			)
		: sourceModels;

	return sortMatrixRows(
		rows,
		metric,
		sortDatasetName,
		sortDirection,
		detailMatrixDatasets,
		datasetCells
	);
}

export function benchmarkRows(
	groupName: string | null,
	models: readonly GuardModel[]
): BenchmarkRankingRow[] {
	if (!groupName) return [];
	const metric = benchmarkLeaderMetric(groupName, models);

	return models
		.map((model) => {
			const group = model.groups[groupName];
			return {
				model,
				score: group?.f1 ?? null,
				fpr: group?.fpr ?? null,
				fnr: group?.fnr ?? null,
				hasData: isNumber(group?.f1) || isNumber(group?.fpr) || isNumber(group?.fnr)
			};
		})
		.sort((a, b) => {
			if (a.hasData !== b.hasData) return a.hasData ? -1 : 1;
			const aValue = benchmarkRowMetricValue(a, metric);
			const bValue = benchmarkRowMetricValue(b, metric);
			const aEmpty = !isNumber(aValue);
			const bEmpty = !isNumber(bValue);
			if (aEmpty && bEmpty) return 0;
			if (aEmpty) return 1;
			if (bEmpty) return -1;

			return metric === 'f1' ? (bValue ?? 0) - (aValue ?? 0) : (aValue ?? 0) - (bValue ?? 0);
		});
}

function benchmarkLeaderMetric(
	groupName: string,
	models: readonly GuardModel[]
): BenchmarkLeaderMetric | null {
	const metrics: BenchmarkLeaderMetric[] = ['f1', 'fnr', 'fpr'];
	return (
		metrics.find((metric) => models.some((model) => isNumber(model.groups[groupName]?.[metric]))) ??
		null
	);
}

function benchmarkMetricValue(group: GroupScore | undefined, metric: BenchmarkLeaderMetric | null) {
	if (!group || !metric) return null;
	return group[metric];
}

function benchmarkRowMetricValue(row: BenchmarkRankingRow, metric: BenchmarkLeaderMetric | null) {
	if (!metric) return null;
	return metric === 'f1' ? row.score : row[metric];
}

function benchmarkLeader(
	groupName: string,
	models: readonly GuardModel[]
): BenchmarkCard['leader'] {
	const metric = benchmarkLeaderMetric(groupName, models);
	if (!metric) return null;

	return models.reduce<BenchmarkCard['leader']>((leader, model) => {
		const group = model.groups[groupName];
		const value = benchmarkMetricValue(group, metric);
		if (!isNumber(value)) return leader;
		if (leader && (metric === 'f1' ? leader.value >= value : leader.value <= value)) return leader;

		return {
			modelShort: model.short,
			value,
			metric
		};
	}, null);
}

export function buildBenchmarkCards(
	search: string,
	language: BenchmarkFamilyLanguage,
	dataset: DetailsDataset,
	locale: SupportedLocale
) {
	const normalizedSearch = search.trim().toLowerCase();

	return dataset.allGroups
		.filter((group) => {
			const meta = dataset.benchmarkMeta[group];
			if (!meta) return false;
			if (language !== 'all' && !meta.languages.includes(language)) return false;
			if (!normalizedSearch) return true;

			return [
				localized(dataset.groupLabels[group], locale, group),
				localized(meta.description, locale, '')
			]
				.join(' ')
				.toLowerCase()
				.includes(normalizedSearch);
		})
		.map<BenchmarkCard>((group) => ({
			name: group,
			meta: dataset.benchmarkMeta[group],
			leader: benchmarkLeader(group, dataset.models)
		}));
}

export function matchesLanguage(model: GuardModel, language: DetailsLanguageFilter) {
	if (language === 'any') return true;
	return model.languages.includes(language);
}

export function matchesSize(model: GuardModel, filter: SizeFilter) {
	if (filter === 'all') return true;

	const size = sizeNumber(model.params);
	if (filter === 'small') return size < 1;
	if (filter === 'medium') return size >= 1 && size <= 8;
	return size > 8;
}

export function modelSortValue(model: GuardModel, sort: ModelSort) {
	if (sort === 'f1') return model.f1;
	if (sort === 'p95') return -model.p95;
	if (sort === 'size') return sizeNumber(model.params);
	return model.integral;
}

export function filterModels(
	search: string,
	language: DetailsLanguageFilter,
	type: ModelTypeFilter,
	size: SizeFilter,
	sort: ModelSort,
	models: readonly GuardModel[]
) {
	const normalizedSearch = search.trim().toLowerCase();

	return [...models]
		.filter((model) => {
			if (type !== 'all' && model.type !== type) return false;
			if (!matchesSize(model, size)) return false;
			if (!matchesLanguage(model, language)) return false;
			if (!normalizedSearch) return true;

			return [model.short, model.name, model.family, model.org]
				.join(' ')
				.toLowerCase()
				.includes(normalizedSearch);
		})
		.sort((a, b) => modelSortValue(b, sort) - modelSortValue(a, sort));
}

export function detailMatrixRowsToCsv(
	rows: readonly GuardModel[],
	groups: readonly MatrixGroup[],
	metric: DetailMetric,
	datasetCells: Record<string, Record<string, DetailsDatasetMatrixCell>>
) {
	const datasets = groups.flatMap((group) =>
		group.datasets.map((dataset) => ({
			...dataset,
			header: `${group.label} / ${dataset.label} ${metric}`
		}))
	);
	const header = [
		'rank',
		'model',
		'organization',
		'size',
		'integral',
		'metric',
		...datasets.map((dataset) => dataset.header)
	];
	const lines = rows.map((model, index) => [
		index + 1,
		model.name,
		model.org,
		model.params,
		csvNumber(model.integral),
		metric,
		...datasets.map((dataset) =>
			csvNumber(detailMetricValue(datasetCells[modelKey(model)]?.[dataset.id], metric))
		)
	]);

	return [header, ...lines].map((row) => row.map(csvCell).join(',')).join('\n');
}

export function detailModelRowsToCsv(rows: readonly GuardModel[]) {
	const header = [
		'rank',
		'model',
		'organization',
		'family',
		'type',
		'license',
		'size',
		'languages',
		'integral',
		'min_group',
		'overall_fpr',
		'overall_fnr',
		'overall_f1',
		'p50_ms',
		'p95_ms',
		'p99_ms',
		'run_date'
	];
	const lines = rows.map((model, index) => [
		index + 1,
		model.name,
		model.org,
		model.family,
		model.type,
		model.license,
		model.params,
		model.languages.join('; '),
		csvNumber(model.integral),
		csvNumber(model.minGroup),
		csvNumber(model.fpr),
		csvNumber(model.fnr),
		csvNumber(model.f1),
		csvNumber(model.p50, 1),
		csvNumber(model.p95, 1),
		csvNumber(model.p99, 1),
		model.runDate
	]);

	return [header, ...lines].map((row) => row.map(csvCell).join(',')).join('\n');
}

function groupName(key: string, dataset: DetailsDataset, locale: SupportedLocale) {
	return localized(dataset.groupLabels[key], locale, key);
}

export function modelGroupRows(
	model: GuardModel | null,
	dataset: DetailsDataset,
	locale: SupportedLocale
) {
	if (!model) return [];

	return Object.entries(model.groups)
		.map<ModelGroupRow>(([name, group]) => ({
			name: groupName(name, dataset, locale),
			score: group.score,
			recall: group.recall ?? null,
			precision: group.precision ?? null
		}))
		.sort((a, b) => b.score - a.score);
}

export function modelRadarGroups(
	model: GuardModel | null,
	dataset: DetailsDataset,
	locale: SupportedLocale
) {
	if (!model) return [];

	const rows: ModelGroupRow[] = [];
	for (const name of dataset.allGroups) {
		const group = model.groups[name];
		if (!group || !isNumber(group.score)) continue;
		rows.push({
			name: groupName(name, dataset, locale),
			score: group.score,
			recall: group.recall ?? null,
			precision: group.precision ?? null
		});
	}

	return rows;
}

export function weakestModelGroups(groups: readonly ModelGroupRow[]) {
	return [...groups].reverse().slice(0, 5);
}

export function radarPoint(index: number, total: number, radius: number) {
	if (!total) return [160, 160] as const;
	const angle = -Math.PI / 2 + (2 * Math.PI * index) / total;
	return [160 + Math.cos(angle) * radius, 160 + Math.sin(angle) * radius] as const;
}

export function shortRadarLabel(label: string) {
	return label.length > 14 ? `${label.slice(0, 13)}...` : label;
}

export function radarPoints(groups: readonly ModelGroupRow[]) {
	const total = groups.length;
	if (!total) return [];

	return groups.map<RadarPoint>((group, index) => {
		const [x, y] = radarPoint(index, total, 118 * Math.max(0, Math.min(1, group.score)));
		const [labelX, labelY] = radarPoint(index, total, 142);
		return {
			...group,
			x,
			y,
			labelX,
			labelY,
			label: shortRadarLabel(group.name),
			anchor: labelX < 155 ? 'end' : labelX > 165 ? 'start' : 'middle'
		};
	});
}

export function radarPolygon(points: readonly RadarPoint[]) {
	return points.map((point) => `${point.x.toFixed(1)},${point.y.toFixed(1)}`).join(' ');
}

export function radarGridPolygons(groups: readonly ModelGroupRow[]) {
	return [0.25, 0.5, 0.75, 1].map((scale) =>
		groups
			.map((_, index) => {
				const [x, y] = radarPoint(index, groups.length, 118 * scale);
				return `${x.toFixed(1)},${y.toFixed(1)}`;
			})
			.join(' ')
	);
}