import { Injectable, inject } from '@angular/core';
import { Result, ok, err } from '@shared/kernel/fp';
import { runSubmit } from '@shared/application/submit';
import { ApiClient, StamdataColumnDto } from '@shared/infrastructure/api-client';
import { ColumnType, StamColumn, StamRow, StamTable } from '@beheer/domain/stamdata';

/** A loaded table: its schema plus the rows for editing (or the peildatum-filtered view). */
export interface LoadedTable {
  table: StamTable;
  rows: StamRow[];
}

const FAILED = $localize`:@@beheer.load.failed:De stamdata kon niet worden geladen.`;
const COLUMN_TYPES: readonly ColumnType[] = ['text', 'date', 'number', 'enum'];

/**
 * The only place stamdata HTTP lives (ADR-0001 boundary). Both endpoints are reads; the
 * generic `parse*` narrows the untrusted wire shape (schema + opaque rows) into the domain
 * model. There is no write method — the edit is downloaded and lands as a PR.
 */
@Injectable({ providedIn: 'root' })
export class StamdataAdapter {
  private client = inject(ApiClient);

  /** The tables in the catalog (schema only, no rows) — for the table switcher. */
  async list(): Promise<Result<string, StamTable[]>> {
    const r = await runSubmit(() => this.client.stamdataTables(), FAILED);
    if (!r.ok) return r;
    const out: StamTable[] = [];
    for (const t of r.value ?? []) {
      const parsed = parseTable(t);
      if (!parsed.ok) return parsed;
      out.push(parsed.value);
    }
    return ok(out);
  }

  /** One table's schema + rows. `peildatum` (yyyy-MM-dd) asks the server for only the rows
      valid on that date; the editor uses it for a server-side cross-check, previewing
      locally for instant feedback (see `activeOn`). */
  async load(tableId: string, peildatum?: string): Promise<Result<string, LoadedTable>> {
    const r = await runSubmit(() => this.client.stamdataTable(tableId, peildatum), FAILED);
    return r.ok ? parseStamdataTable(r.value) : r;
  }
}

// --- parse: wire → domain, validating at the boundary ---

/** Trust-boundary parse for one table response: schema + rows → domain. Exported so its
    spec can exercise it without HTTP (the house `parse*` seam, ADR-0001). */
export function parseStamdataTable(dto: {
  id?: string;
  label?: string;
  columns?: StamdataColumnDto[];
  temporal?: boolean;
  rows?: readonly unknown[];
}): Result<string, LoadedTable> {
  const table = parseTable(dto);
  if (!table.ok) return table;
  return ok({ table: table.value, rows: parseRows(dto.rows ?? [], table.value.columns) });
}

function parseColumn(dto: StamdataColumnDto): Result<string, StamColumn> {
  if (typeof dto.name !== 'string' || dto.name === '') return err('stamdata column: bad name');
  const raw = dto.type ?? '';
  const type = (COLUMN_TYPES as string[]).includes(raw) ? (raw as ColumnType) : 'text';
  return ok({ name: dto.name, type, isKey: dto.isKey === true, options: dto.options ?? [] });
}

function parseTable(dto: { id?: string; label?: string; columns?: StamdataColumnDto[]; temporal?: boolean }): Result<string, StamTable> {
  if (typeof dto.id !== 'string' || !Array.isArray(dto.columns))
    return err('stamdata table: bad shape');
  const columns: StamColumn[] = [];
  for (const c of dto.columns) {
    const parsed = parseColumn(c);
    if (!parsed.ok) return parsed;
    columns.push(parsed.value);
  }
  if (columns.length === 0) return err('stamdata table: no columns');
  return ok({ id: dto.id, label: dto.label ?? dto.id, columns, temporal: dto.temporal === true });
}

/** Every cell becomes editable text: null → '' (open-ended), number/bool → its string form. */
function parseRows(rows: readonly unknown[], columns: readonly StamColumn[]): StamRow[] {
  return rows.map((raw) => {
    const row: StamRow = {};
    const obj = (raw ?? {}) as Record<string, unknown>;
    for (const c of columns) {
      const v = obj[c.name];
      row[c.name] = v === null || v === undefined ? '' : String(v);
    }
    return row;
  });
}