import { jsPDF } from 'jspdf';
import autoTable from 'jspdf-autotable';

/** LLMagnet brand palette (purple / plum / accent) */
export const REPORT_COLORS = {
  primary: [124, 58, 237] as [number, number, number],
  accent: [219, 39, 119] as [number, number, number],
  border: [242, 215, 242] as [number, number, number],
  text: [17, 24, 39] as [number, number, number],
  muted: [107, 114, 128] as [number, number, number],
  headerBg: [250, 245, 255] as [number, number, number],
};

const HEADER_BAND_H = 26;
const PAGE_MARGIN = 14;
const HEADER_LOGO_TOP = 7;

function formatNow(): string {
  return new Date().toLocaleString(undefined, {
    dateStyle: 'medium',
    timeStyle: 'short',
  });
}

export async function loadLogoDataUrl(pluginUrl: string): Promise<string | null> {
  const base = pluginUrl.replace(/\/?$/, '/');
  const url = `${base}assets/react-build/assets/llmmagnetlogo.svg`;
  return new Promise((resolve) => {
    const img = new Image();
    img.crossOrigin = 'anonymous';
    img.onload = () => {
      try {
        const w = 64;
        const h = 64;
        const canvas = document.createElement('canvas');
        canvas.width = w;
        canvas.height = h;
        const ctx = canvas.getContext('2d');
        if (!ctx) {
          resolve(null);
          return;
        }
        ctx.drawImage(img, 0, 0, w, h);
        resolve(canvas.toDataURL('image/png'));
      } catch {
        resolve(null);
      }
    };
    img.onerror = () => resolve(null);
    img.src = url;
  });
}

function drawHeaderBand(
  doc: jsPDF,
  pageWidth: number,
  opts: {
    logoDataUrl: string | null;
    reportTitle: string;
    pageNum: number;
  }
) {
  doc.setFillColor(REPORT_COLORS.headerBg[0], REPORT_COLORS.headerBg[1], REPORT_COLORS.headerBg[2]);
  doc.rect(0, 0, pageWidth, HEADER_BAND_H + 2, 'F');
  doc.setDrawColor(REPORT_COLORS.border[0], REPORT_COLORS.border[1], REPORT_COLORS.border[2]);
  doc.setLineWidth(0.3);
  doc.line(0, HEADER_BAND_H + 2, pageWidth, HEADER_BAND_H + 2);

  let x = PAGE_MARGIN;
  if (opts.logoDataUrl) {
    try {
      doc.addImage(opts.logoDataUrl, 'PNG', x, HEADER_LOGO_TOP - 2, 10, 10);
      x += 14;
    } catch {
      // ignore
    }
  }

  doc.setTextColor(REPORT_COLORS.primary[0], REPORT_COLORS.primary[1], REPORT_COLORS.primary[2]);
  doc.setFont('helvetica', 'bold');
  doc.setFontSize(11);
  doc.text('LLMagnet', x, HEADER_LOGO_TOP + 6);

  doc.setTextColor(REPORT_COLORS.muted[0], REPORT_COLORS.muted[1], REPORT_COLORS.muted[2]);
  doc.setFont('helvetica', 'normal');
  doc.setFontSize(8);
  doc.text(opts.reportTitle, x + 42, HEADER_LOGO_TOP + 6);

  doc.text(`Page ${opts.pageNum}`, pageWidth - PAGE_MARGIN, HEADER_LOGO_TOP + 6, { align: 'right' });
}

function tableStartAfterMeta(metaLines: string[], summaryTailMm: number): number {
  return (
    HEADER_BAND_H +
    6 +
    7 +
    5 +
    5 +
    metaLines.length * 4.5 +
    8 +
    summaryTailMm
  );
}

export interface BotAnalyticsPdfRow {
  bot: string;
  visits: string;
  clicks: string;
  ctr: string;
  trend: string;
}

export async function createBotAnalyticsPdf(params: {
  pluginUrl: string;
  siteName: string;
  reportTitle: string;
  metaLines: string[];
  tableRows: BotAnalyticsPdfRow[];
}): Promise<jsPDF> {
  const logo = await loadLogoDataUrl(params.pluginUrl);
  const doc = new jsPDF({ unit: 'mm', format: 'a4' });
  const pageW = doc.internal.pageSize.getWidth();

  const head = [['Bot', 'Visits', 'Clicks', 'CTR', 'Trend']];
  const body = params.tableRows.map((r) => [
    r.bot,
    r.visits,
    r.clicks,
    r.ctr,
    r.trend,
  ]);

  const tableStartY = tableStartAfterMeta(params.metaLines, 0);

  autoTable(doc, {
    head,
    body,
    startY: tableStartY,
    margin: { left: PAGE_MARGIN, right: PAGE_MARGIN, bottom: 16, top: HEADER_BAND_H + 2 },
    styles: {
      fontSize: 9,
      cellPadding: 2.5,
      textColor: REPORT_COLORS.text,
    },
    headStyles: {
      fillColor: REPORT_COLORS.primary,
      textColor: 255,
      fontStyle: 'bold',
    },
    alternateRowStyles: { fillColor: [252, 250, 255] },
    theme: 'striped',
    willDrawPage: (data) => {
      drawHeaderBand(data.doc, pageW, {
        logoDataUrl: logo,
        reportTitle: params.reportTitle,
        pageNum: data.pageNumber,
      });
      if (data.pageNumber !== 1) return;
      let yy = HEADER_BAND_H + 6;
      data.doc.setTextColor(REPORT_COLORS.text[0], REPORT_COLORS.text[1], REPORT_COLORS.text[2]);
      data.doc.setFont('helvetica', 'bold');
      data.doc.setFontSize(14);
      data.doc.text('Bot Analytics', PAGE_MARGIN, yy);
      yy += 7;
      data.doc.setFont('helvetica', 'normal');
      data.doc.setFontSize(9);
      data.doc.setTextColor(REPORT_COLORS.muted[0], REPORT_COLORS.muted[1], REPORT_COLORS.muted[2]);
      data.doc.text(params.siteName, PAGE_MARGIN, yy);
      yy += 5;
      data.doc.text(`Generated: ${formatNow()}`, PAGE_MARGIN, yy);
      yy += 5;
      params.metaLines.forEach((line) => {
        data.doc.text(line, PAGE_MARGIN, yy);
        yy += 4.5;
      });
    },
  });

  return doc;
}

export interface PageStatPdfRow {
  page: string;
  visits: string;
  clicks: string;
  ctr: string;
  models: string;
}

export async function createPagesReportPdf(params: {
  pluginUrl: string;
  siteName: string;
  reportTitle: string;
  metaLines: string[];
  rows: PageStatPdfRow[];
}): Promise<jsPDF> {
  const logo = await loadLogoDataUrl(params.pluginUrl);
  const doc = new jsPDF({ unit: 'mm', format: 'a4' });
  const pageW = doc.internal.pageSize.getWidth();

  const head = [['Page', 'Bot visits', 'Clicks', 'CTR', 'Models']];
  const body = params.rows.map((r) => [r.page, r.visits, r.clicks, r.ctr, r.models]);

  const tableStartY = tableStartAfterMeta(params.metaLines, 0);

  autoTable(doc, {
    head,
    body,
    startY: tableStartY,
    margin: { left: PAGE_MARGIN, right: PAGE_MARGIN, bottom: 16, top: HEADER_BAND_H + 2 },
    styles: { fontSize: 8, cellPadding: 2, textColor: REPORT_COLORS.text },
    headStyles: {
      fillColor: REPORT_COLORS.primary,
      textColor: 255,
      fontStyle: 'bold',
    },
    columnStyles: {
      0: { cellWidth: 62 },
      4: { cellWidth: 42 },
    },
    alternateRowStyles: { fillColor: [252, 250, 255] },
    theme: 'striped',
    willDrawPage: (data) => {
      drawHeaderBand(data.doc, pageW, {
        logoDataUrl: logo,
        reportTitle: params.reportTitle,
        pageNum: data.pageNumber,
      });
      if (data.pageNumber !== 1) return;
      let yy = HEADER_BAND_H + 6;
      data.doc.setTextColor(REPORT_COLORS.text[0], REPORT_COLORS.text[1], REPORT_COLORS.text[2]);
      data.doc.setFont('helvetica', 'bold');
      data.doc.setFontSize(14);
      data.doc.text('Pages', PAGE_MARGIN, yy);
      yy += 7;
      data.doc.setFont('helvetica', 'normal');
      data.doc.setFontSize(9);
      data.doc.setTextColor(REPORT_COLORS.muted[0], REPORT_COLORS.muted[1], REPORT_COLORS.muted[2]);
      data.doc.text(params.siteName, PAGE_MARGIN, yy);
      yy += 5;
      data.doc.text(`Generated: ${formatNow()}`, PAGE_MARGIN, yy);
      yy += 5;
      params.metaLines.forEach((line) => {
        data.doc.text(line, PAGE_MARGIN, yy);
        yy += 4.5;
      });
    },
  });

  return doc;
}

export interface ProductPdfRow {
  name: string;
  impressions: string;
  clicks: string;
  ctr: string;
  addToCart: string;
  revenue: string;
}

export async function createProductsReportPdf(params: {
  pluginUrl: string;
  siteName: string;
  reportTitle: string;
  metaLines: string[];
  summaryLines: string[];
  rows: ProductPdfRow[];
}): Promise<jsPDF> {
  const logo = await loadLogoDataUrl(params.pluginUrl);
  const doc = new jsPDF({ unit: 'mm', format: 'a4' });
  const pageW = doc.internal.pageSize.getWidth();

  const head = [['Product', 'Impr.', 'Clicks', 'CTR', 'Add to cart', 'Revenue']];
  const body = params.rows.map((r) => [
    r.name,
    r.impressions,
    r.clicks,
    r.ctr,
    r.addToCart,
    r.revenue,
  ]);

  const summaryTail =
    3 + 5 + params.summaryLines.length * 4 + 8;
  const tableStartY = tableStartAfterMeta(params.metaLines, summaryTail);

  autoTable(doc, {
    head,
    body,
    startY: tableStartY,
    margin: { left: PAGE_MARGIN, right: PAGE_MARGIN, bottom: 16, top: HEADER_BAND_H + 2 },
    styles: { fontSize: 7.5, cellPadding: 1.8, textColor: REPORT_COLORS.text },
    headStyles: {
      fillColor: REPORT_COLORS.primary,
      textColor: 255,
      fontStyle: 'bold',
    },
    columnStyles: {
      0: { cellWidth: 52 },
    },
    alternateRowStyles: { fillColor: [252, 250, 255] },
    theme: 'striped',
    willDrawPage: (data) => {
      drawHeaderBand(data.doc, pageW, {
        logoDataUrl: logo,
        reportTitle: params.reportTitle,
        pageNum: data.pageNumber,
      });
      if (data.pageNumber !== 1) return;
      let yy = HEADER_BAND_H + 6;
      data.doc.setTextColor(REPORT_COLORS.text[0], REPORT_COLORS.text[1], REPORT_COLORS.text[2]);
      data.doc.setFont('helvetica', 'bold');
      data.doc.setFontSize(14);
      data.doc.text('Products', PAGE_MARGIN, yy);
      yy += 7;
      data.doc.setFont('helvetica', 'normal');
      data.doc.setFontSize(9);
      data.doc.setTextColor(REPORT_COLORS.muted[0], REPORT_COLORS.muted[1], REPORT_COLORS.muted[2]);
      data.doc.text(params.siteName, PAGE_MARGIN, yy);
      yy += 5;
      data.doc.text(`Generated: ${formatNow()}`, PAGE_MARGIN, yy);
      yy += 5;
      params.metaLines.forEach((line) => {
        data.doc.text(line, PAGE_MARGIN, yy);
        yy += 4.5;
      });
      yy += 3;
      data.doc.setFont('helvetica', 'bold');
      data.doc.setFontSize(9);
      data.doc.setTextColor(REPORT_COLORS.primary[0], REPORT_COLORS.primary[1], REPORT_COLORS.primary[2]);
      data.doc.text('Summary', PAGE_MARGIN, yy);
      yy += 5;
      data.doc.setFont('helvetica', 'normal');
      data.doc.setFontSize(8.5);
      data.doc.setTextColor(REPORT_COLORS.text[0], REPORT_COLORS.text[1], REPORT_COLORS.text[2]);
      params.summaryLines.forEach((line) => {
        data.doc.text(line, PAGE_MARGIN, yy);
        yy += 4;
      });
    },
  });

  return doc;
}

export function arrayBufferToBase64(buffer: ArrayBuffer): string {
  let binary = '';
  const bytes = new Uint8Array(buffer);
  for (let i = 0; i < bytes.byteLength; i++) {
    binary += String.fromCharCode(bytes[i]);
  }
  return window.btoa(binary);
}