import {
  PWWLO_REGEX,
  normalizeContent,
  validateCallsign,
  validateCallsignList,
  isMultiOp,
  isSingleOp,
} from "@/utils/ediValidation";
import i18n from "@/i18n";
import { type EdiHeaderForm } from "@/types/edi";

const translate = (key: string, options?: Record<string, unknown>, fallback?: string) => {
  const value = i18n.t(key, options);
  if (fallback && (value === key || value === "")) return fallback;
  return value as string;
};

export const validateEdi = (content: string, name: string): string[] => {
  const errors: string[] = [];
  const lines = normalizeContent(content).split("\n");
  const nonEmpty = lines.map((l) => l.trim()).filter((l) => l.length > 0);
  let tDateStart: number | null = null;
  let tDateEnd: number | null = null;
  let tDateStartYear: number | null = null;
  let tDateEndYear: number | null = null;
  let tDateValid = false;
  if (nonEmpty.length === 0) {
    errors.push(
      translate("edi_error_file_empty", { name }, `${name}: soubor je prázdný.`)
    );
    return errors;
  }

  if (!nonEmpty[0].startsWith("[REG1TEST")) {
    errors.push(
      translate(
        "edi_error_missing_header",
        { name },
        `${name}: chybí hlavička [REG1TEST;1].`
      )
    );
  }

  const headerMap: Record<string, string> = {};
  let remarksStart = -1;
  let qsoStart = -1;

  nonEmpty.forEach((line, idx) => {
    if (line.startsWith("[Remarks")) remarksStart = idx;
    if (line.startsWith("[QSORecords")) qsoStart = idx;
    const m = line.match(/^([A-Za-z0-9]+)=(.*)$/);
    if (m) {
      headerMap[m[1]] = m[2].trim();
    }
  });

  // Required header fields
  const requiredFields: Array<[keyof EdiHeaderForm, string]> = [
    ["TName", translate("edi_field_tname", undefined, "název soutěže (TName)")],
    ["TDate", translate("edi_field_tdate", undefined, "datum závodu (TDate=YYYYMMDD;YYYYMMDD)")],
    ["PCall", translate("edi_field_pcall", undefined, "volací znak (PCall)")],
    ["PWWLo", translate("edi_field_pwwlo", undefined, "lokátor (PWWLo)")],
    ["PSect", translate("edi_field_psect", undefined, "sekce/kategorie (PSect)")],
    ["PBand", translate("edi_field_pband", undefined, "použité pásmo (PBand)")],
    ["SPowe", translate("edi_field_spowe", undefined, "výkon (SPowe)")],
    ["SAnte", translate("edi_field_sante", undefined, "anténa (SAnte)")],
    ["CQSOP", translate("edi_field_cqsop", undefined, "QSO body (CQSOP)")],
    ["CToSc", translate("edi_field_ctosc", undefined, "celkové body (CToSc)")],
  ];
  requiredFields.forEach(([key, label]) => {
    if (!headerMap[key] || headerMap[key].trim() === "") {
      errors.push(
        translate(
          "edi_error_missing_field",
          { name, field: label },
          `${name}: chybí ${label}.`
        )
      );
    }
  });

  if (headerMap["TDate"]) {
    const parts = headerMap["TDate"].split(";");
    const invalidCount = parts.length !== 2;
    const invalidFormat = parts.some((p) => !/^\d{8}$/.test(p));
    const invertedRange = !invalidCount && !invalidFormat && parseInt(parts[0], 10) > parseInt(parts[1], 10);
    if (invalidCount || invalidFormat || invertedRange) {
      errors.push(
        translate(
          "edi_error_tdate_format",
          { name },
          `${name}: TDate musí být ve formátu YYYYMMDD;YYYYMMDD a první datum nesmí být větší než druhé.`
        )
      );
    } else {
      tDateStart = parseInt(parts[0], 10);
      tDateEnd = parseInt(parts[1], 10);
      tDateStartYear = parseInt(parts[0].slice(0, 4), 10);
      tDateEndYear = parseInt(parts[1].slice(0, 4), 10);
      tDateValid = true;
    }
  }

  if (headerMap["PWWLo"]) {
    const normalizedPwwlo = headerMap["PWWLo"].trim().toUpperCase();
    if (!PWWLO_REGEX.test(normalizedPwwlo)) {
      errors.push(
        translate(
          "edi_error_pwwlo_format",
          { name },
          `${name}: PWWLo musí mít 6 znaků ve formátu lokátoru (AA00AA).`
        )
      );
    }
    headerMap["PWWLo"] = normalizedPwwlo;
  }

  if (headerMap["RHBBS"] && !/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(headerMap["RHBBS"])) {
    // měkká validace, řeší se upozorněním ve formuláři
  }

  const pcallValidation = validateCallsign(headerMap["PCall"] ?? "");
  if (!pcallValidation.isValid) {
    errors.push(
      translate(
        "edi_error_pcall_format",
        { name },
        `${name}: PCall musí být validní volací znak.`
      )
    );
  } else {
    headerMap["PCall"] = pcallValidation.normalized;
  }

  const section = headerMap["PSect"] ?? "";
  const requiresSingle = isSingleOp(section);
  const requiresMulti = isMultiOp(section);
  if (requiresSingle || requiresMulti) {
    const rcallValidation = validateCallsign(headerMap["RCall"] ?? "");
    if (!rcallValidation.isValid) {
      errors.push(
        translate(
          "edi_error_rcall_for_psect",
          { name, psect: section },
          `${name}: chybí nebo je neplatné RCall pro PSect ${section}.`
        )
      );
    }
    if (requiresMulti) {
      const mope1Val = validateCallsignList(headerMap["MOpe1"] ?? "");
      const mope2Val = validateCallsignList(headerMap["MOpe2"] ?? "");
      const hasAnyValid = mope1Val.hasValid || mope2Val.hasValid;
      const invalidTokens = [...mope1Val.invalidTokens, ...mope2Val.invalidTokens];
      if (!hasAnyValid) {
        errors.push(
          translate(
            "edi_error_mope_missing",
            { name },
            `${name}: chybí MOpe1/MOpe2 pro multi operátory.`
          )
        );
      }
      if (invalidTokens.length > 0) {
        errors.push(
          translate(
            "edi_error_mope_invalid",
            { name, invalid: invalidTokens.join(", ") },
            `${name}: neplatné značky v MOpe1/MOpe2 (${invalidTokens.join(", ")}).`
          )
        );
      }
    }
  }

  if (qsoStart === -1) {
    errors.push(
      translate(
        "edi_error_missing_qso_records",
        { name },
        `${name}: chybí sekce [QSORecords;N].`
      )
    );
    return errors;
  }

  const qsoHeader = nonEmpty[qsoStart];
  const m = qsoHeader.match(/^\[QSORecords;(\d+)\]/);
  const expectedCount = m ? parseInt(m[1], 10) : null;

  const qsoLines: string[] = [];
  for (let i = qsoStart + 1; i < nonEmpty.length; i++) {
    const line = nonEmpty[i];
    if (line.startsWith("[END")) break;
    if (line.startsWith("[") && !line.startsWith("[QSORecords")) break;
    qsoLines.push(line);
  }
  if (expectedCount !== null && qsoLines.length !== expectedCount) {
    // upozornění řeší computeQsoCountWarning, tady neblokujeme upload
  }

  let hasQsoValidationError = false;
  qsoLines.forEach((line, idx) => {
    const parts = line.split(";");
    if (parts.length < 10) {
      errors.push(
        translate(
          "edi_error_qso_fields_min",
          { name, index: idx + 1, min: 10 },
          `${name}: QSO #${idx + 1} má málo polí (minimálně 10 očekáváno).`
        )
      );
      hasQsoValidationError = true;
      return;
    }
    const date = parts[0] ?? "";
    const time = parts[1] ?? "";
    const call = parts[2] ?? "";
    if (!/^\d{6}$/.test(date)) {
      errors.push(
        translate(
          "edi_error_qso_date_format",
          { name, index: idx + 1 },
          `${name}: QSO #${idx + 1} má neplatné datum (YYMMDD).`
        )
      );
      hasQsoValidationError = true;
    } else if (tDateValid && tDateStart !== null && tDateEnd !== null) {
      const yy = parseInt(date.slice(0, 2), 10);
      const mmdd = date.slice(2);
      let fullYear: number | null = null;
      if (tDateStartYear !== null && tDateEndYear !== null) {
        if (tDateStartYear === tDateEndYear) {
          fullYear = tDateStartYear;
        } else if (yy === tDateStartYear % 100) {
          fullYear = tDateStartYear;
        } else if (yy === tDateEndYear % 100) {
          fullYear = tDateEndYear;
        }
      }
      if (fullYear === null) {
        errors.push(
          translate(
            "edi_error_qso_year_out_of_range",
            { name, index: idx + 1 },
            `${name}: QSO #${idx + 1} má rok mimo rozsah TDate.`
          )
        );
        hasQsoValidationError = true;
      } else {
        const fullDate = parseInt(`${fullYear}${mmdd}`, 10);
        if (fullDate < tDateStart || fullDate > tDateEnd) {
          errors.push(
            translate(
              "edi_error_qso_date_out_of_range",
              { name, index: idx + 1 },
              `${name}: QSO #${idx + 1} má datum mimo rozsah TDate.`
            )
          );
          hasQsoValidationError = true;
        }
      }
    }
    if (!/^\d{4}$/.test(time)) {
      errors.push(
        translate(
          "edi_error_qso_time_format",
          { name, index: idx + 1 },
          `${name}: QSO #${idx + 1} má neplatný čas (HHMM UTC).`
        )
      );
      hasQsoValidationError = true;
    }
    const qsoCallValidation = validateCallsign(call);
    if (!qsoCallValidation.isValid) {
      errors.push(
        translate(
          "edi_error_qso_callsign",
          { name, index: idx + 1 },
          `${name}: QSO #${idx + 1} má neplatný volací znak.`
        )
      );
      hasQsoValidationError = true;
    }
  });

  if (hasQsoValidationError) {
    errors.push(
      translate(
        "edi_error_qso_edit_in_file",
        { name },
        `${name}: Záznamy QSO nelze upravit ve formuláři, oprav je v souboru a zkus ho nahrát znovu.`
      )
    );
  }

  return errors;
};