import {
  AlignmentType,
  Document,
  HeightRule,
  ImageRun,
  Packer,
  PageOrientation,
  Paragraph,
  Table,
  TableCell,
  TableRow,
  TextRun,
  WidthType,
  BorderStyle,
  Footer,
  LevelFormat,
  PageNumber,
} from "docx";
import pkg from "file-saver";
const { saveAs } = pkg;

export interface PleadingFootnote {
  id: number;
  text: string;
}

export interface PleadingSignature {
  /** Multi-line block placed under the signature line (name, bar no., firm, etc.) */
  block: string;
  /** Optional typed signature (rendered in a cursive script font above the line) */
  typed?: string;
  /** Optional PNG/JPG bytes of a scanned signature placed above the line (for DOCX) */
  imageBytes?: ArrayBuffer | Uint8Array;
  /** Same image as a data URL (for PDF generator, which needs a string) */
  imageDataUrl?: string;
  imageType?: "png" | "jpg" | "jpeg";
}

export interface PleadingInput {
  courtType: "CIRCUIT" | "COUNTY";
  circuit: string; // e.g. "ELEVENTH"
  county: string; // e.g. "Miami-Dade"
  plaintiffs: string; // multi-line
  defendants: string; // multi-line
  caseNumber: string;
  title?: string;
  bodyHtml?: string; // rich HTML body
  body?: string; // legacy plain text fallback
  footnotes?: PleadingFootnote[];
  footerLeft?: string;
  footerCenter?: string;
  footerRight?: string; // user text prepended to "Page X of Y"
  signature?: PleadingSignature;
}

const FONT = "Bookman Old Style";
const SIZE = 24; // 12pt (docx uses half-points)

const noBorder = {
  top: { style: BorderStyle.NONE, size: 0, color: "FFFFFF" },
  bottom: { style: BorderStyle.NONE, size: 0, color: "FFFFFF" },
  left: { style: BorderStyle.NONE, size: 0, color: "FFFFFF" },
  right: { style: BorderStyle.NONE, size: 0, color: "FFFFFF" },
  insideHorizontal: { style: BorderStyle.NONE, size: 0, color: "FFFFFF" },
  insideVertical: { style: BorderStyle.NONE, size: 0, color: "FFFFFF" },
};

const verticalLine = {
  top: { style: BorderStyle.NONE, size: 0, color: "FFFFFF" },
  bottom: { style: BorderStyle.NONE, size: 0, color: "FFFFFF" },
  left: { style: BorderStyle.NONE, size: 0, color: "FFFFFF" },
  right: { style: BorderStyle.SINGLE, size: 8, color: "000000" },
};

function run(text: string, opts: { bold?: boolean; italic?: boolean; underline?: boolean; superscript?: boolean; size?: number } = {}) {
  return new TextRun({
    text,
    bold: opts.bold,
    italics: opts.italic,
    underline: opts.underline ? {} : undefined,
    superScript: opts.superscript,
    font: FONT,
    size: opts.size ?? SIZE,
  });
}

function p(text: string, opts: { bold?: boolean; align?: (typeof AlignmentType)[keyof typeof AlignmentType] } = {}) {
  return new Paragraph({
    alignment: opts.align,
    children: [run(text, { bold: opts.bold })],
  });
}

function emptyP() {
  return new Paragraph({ children: [run("")] });
}

// ---------- HTML → docx Paragraphs ----------

type RunStyle = { bold?: boolean; italic?: boolean; underline?: boolean; superscript?: boolean };

function alignFromStyle(node: Element): (typeof AlignmentType)[keyof typeof AlignmentType] | undefined {
  const ta = (node.getAttribute("style") || "").match(/text-align:\s*(left|center|right|justify)/i)?.[1]?.toLowerCase();
  switch (ta) {
    case "center": return AlignmentType.CENTER;
    case "right": return AlignmentType.RIGHT;
    case "justify": return AlignmentType.JUSTIFIED;
    case "left": return AlignmentType.LEFT;
    default: return undefined;
  }
}

function collectRuns(node: Node, style: RunStyle, out: TextRun[]) {
  if (node.nodeType === Node.TEXT_NODE) {
    const text = node.textContent || "";
    if (text) out.push(run(text, style));
    return;
  }
  if (node.nodeType !== Node.ELEMENT_NODE) return;
  const el = node as Element;
  const tag = el.tagName.toLowerCase();
  const next: RunStyle = { ...style };
  if (tag === "strong" || tag === "b") next.bold = true;
  if (tag === "em" || tag === "i") next.italic = true;
  if (tag === "u") next.underline = true;
  if (tag === "sup") next.superscript = true;
  if (tag === "br") {
    out.push(new TextRun({ text: "", break: 1, font: FONT, size: SIZE }));
    return;
  }
  el.childNodes.forEach((child) => collectRuns(child, next, out));
}

function blockToParagraphs(el: Element, listCtx?: { ref: string; level: number }): Paragraph[] {
  const tag = el.tagName.toLowerCase();
  const align = alignFromStyle(el);

  if (tag === "ul" || tag === "ol") {
    const ref = tag === "ul" ? "pl-bullets" : "pl-numbers";
    const level = (listCtx?.level ?? -1) + 1;
    const out: Paragraph[] = [];
    el.querySelectorAll(":scope > li").forEach((li) => {
      const runs: TextRun[] = [];
      li.childNodes.forEach((child) => {
        if (child.nodeType === Node.ELEMENT_NODE && /^(ul|ol)$/i.test((child as Element).tagName)) return;
        collectRuns(child, {}, runs);
      });
      out.push(new Paragraph({
        numbering: { reference: ref, level },
        children: runs.length ? runs : [run("")],
      }));
      li.querySelectorAll(":scope > ul, :scope > ol").forEach((nested) => {
        out.push(...blockToParagraphs(nested as Element, { ref, level }));
      });
    });
    return out;
  }

  if (tag === "blockquote") {
    const out: Paragraph[] = [];
    el.childNodes.forEach((child) => {
      if (child.nodeType === Node.ELEMENT_NODE) {
        out.push(...blockToParagraphs(child as Element).map((par) => par));
      } else if (child.nodeType === Node.TEXT_NODE && (child.textContent || "").trim()) {
        out.push(new Paragraph({
          alignment: align,
          indent: { left: 720 },
          children: [run(child.textContent || "")],
        }));
      }
    });
    if (out.length === 0) out.push(new Paragraph({ indent: { left: 720 }, children: [run("")] }));
    return out;
  }

  if (tag === "h1" || tag === "h2" || tag === "h3") {
    const runs: TextRun[] = [];
    el.childNodes.forEach((c) => collectRuns(c, { bold: true }, runs));
    return [new Paragraph({ alignment: align, children: runs.length ? runs : [run("")] })];
  }

  // Default: paragraph
  const runs: TextRun[] = [];
  el.childNodes.forEach((c) => collectRuns(c, {}, runs));
  return [new Paragraph({ alignment: align, children: runs.length ? runs : [run("")] })];
}

function htmlToParagraphs(html: string): Paragraph[] {
  if (typeof window === "undefined" || !html) return [];
  const doc = new DOMParser().parseFromString(`<div>${html}</div>`, "text/html");
  const root = doc.body.firstElementChild;
  if (!root) return [];
  const out: Paragraph[] = [];
  Array.from(root.children).forEach((child) => {
    out.push(...blockToParagraphs(child));
  });
  return out;
}

function footerCell(width: number, align: (typeof AlignmentType)[keyof typeof AlignmentType], children: TextRun[]) {
  return new TableCell({
    width: { size: width, type: WidthType.DXA },
    borders: noBorder,
    margins: { top: 40, bottom: 40, left: 60, right: 60 },
    children: [
      new Paragraph({
        alignment: align,
        children: children.length ? children : [run("")],
      }),
    ],
  });
}

function buildFooterTable(left?: string, center?: string, right?: string): Table {
  const total = 9360;
  const col = Math.floor(total / 3);
  const cols = [col, col, total - 2 * col];

  const leftRuns: TextRun[] = left ? [run(left, { size: 20 })] : [];
  const centerRuns: TextRun[] = center ? [run(center, { size: 20 })] : [];

  // Right column: optional user text + always "Page X of Y"
  const rightRuns: TextRun[] = [];
  if (right && right.trim()) {
    rightRuns.push(run(`${right} `, { size: 20 }));
  }
  rightRuns.push(run("Page ", { size: 20 }));
  rightRuns.push(new TextRun({ children: [PageNumber.CURRENT], font: FONT, size: 20 }));
  rightRuns.push(run(" of ", { size: 20 }));
  rightRuns.push(new TextRun({ children: [PageNumber.TOTAL_PAGES], font: FONT, size: 20 }));

  return new Table({
    width: { size: total, type: WidthType.DXA },
    columnWidths: cols,
    borders: noBorder,
    rows: [
      new TableRow({
        children: [
          footerCell(cols[0], AlignmentType.LEFT, leftRuns),
          footerCell(cols[1], AlignmentType.CENTER, centerRuns),
          footerCell(cols[2], AlignmentType.RIGHT, rightRuns),
        ],
      }),
    ],
  });
}

export function buildPleadingDoc(input: PleadingInput): Document {
  const headerLine1 = `IN THE ${input.courtType} COURT OF THE ${input.circuit} JUDICIAL CIRCUIT,`;
  const headerLine2 = `IN AND FOR ${input.county.toUpperCase()} COUNTY, FLORIDA`;

  const plaintiffLines = (input.plaintiffs || "").split("\n").filter((l) => l.trim().length > 0);
  const defendantLines = (input.defendants || "").split("\n").filter((l) => l.trim().length > 0);

  // Left side of caption
  const leftCells: Paragraph[] = [];
  plaintiffLines.forEach((l) => leftCells.push(p(l)));
  if (plaintiffLines.length === 0) leftCells.push(p(""));
  leftCells.push(emptyP());
  leftCells.push(p("Plaintiff(s),"));
  leftCells.push(emptyP());
  leftCells.push(p("v."));
  leftCells.push(emptyP());
  defendantLines.forEach((l) => leftCells.push(p(l)));
  if (defendantLines.length === 0) leftCells.push(p(""));
  leftCells.push(emptyP());
  leftCells.push(p("Defendant(s)."));

  const rightCells: Paragraph[] = [
    p(`CASE NO.: ${input.caseNumber || ""}`, { bold: true }),
  ];

  const captionTable = new Table({
    width: { size: 9360, type: WidthType.DXA },
    columnWidths: [5400, 3960],
    rows: [
      new TableRow({
        height: { value: 400, rule: HeightRule.AUTO },
        children: [
          new TableCell({
            width: { size: 5400, type: WidthType.DXA },
            borders: verticalLine,
            margins: { top: 80, bottom: 80, left: 0, right: 200 },
            children: leftCells,
          }),
          new TableCell({
            width: { size: 3960, type: WidthType.DXA },
            borders: noBorder,
            margins: { top: 80, bottom: 80, left: 200, right: 0 },
            children: rightCells,
          }),
        ],
      }),
    ],
  });

  const bodyParagraphs: Paragraph[] = [];
  if (input.title) {
    bodyParagraphs.push(emptyP());
    bodyParagraphs.push(p(input.title.toUpperCase(), { bold: true, align: AlignmentType.CENTER }));
    bodyParagraphs.push(emptyP());
  }
  if (input.bodyHtml && input.bodyHtml.trim()) {
    bodyParagraphs.push(...htmlToParagraphs(input.bodyHtml));
  } else if (input.body) {
    input.body.split("\n").forEach((line) => bodyParagraphs.push(p(line)));
  }

  // Signature block (above footnotes, after body) — right-side, indented ~2/3 of page width
  const sig = input.signature;
  const SIG_INDENT = 6240; // ~4.33" from left margin (page content is 9360 dxa wide)
  const sigParagraph = (children: TextRun[]) =>
    new Paragraph({ indent: { left: SIG_INDENT }, children });
  if (sig && (sig.block?.trim() || sig.imageBytes || sig.typed?.trim())) {
    bodyParagraphs.push(emptyP());
    bodyParagraphs.push(emptyP());
    if (sig.imageBytes) {
      const data =
        sig.imageBytes instanceof Uint8Array
          ? sig.imageBytes
          : new Uint8Array(sig.imageBytes);
      bodyParagraphs.push(
        new Paragraph({
          indent: { left: SIG_INDENT },
          children: [
            new ImageRun({
              type: (sig.imageType as any) || "png",
              data,
              transformation: { width: 200, height: 60 },
              altText: { title: "Signature", description: "Attorney signature", name: "signature" },
            }),
          ],
        }),
      );
    } else if (sig.typed?.trim()) {
      // Typed cursive signature — script font, larger size
      bodyParagraphs.push(
        new Paragraph({
          indent: { left: SIG_INDENT },
          children: [
            new TextRun({
              text: sig.typed.trim(),
              font: "Lucida Handwriting",
              size: 36,
            }),
          ],
        }),
      );
    } else {
      bodyParagraphs.push(emptyP());
      bodyParagraphs.push(emptyP());
    }
    bodyParagraphs.push(sigParagraph([run("_______________________________")]));
    sig.block.split("\n").forEach((line) =>
      bodyParagraphs.push(sigParagraph([run(line)])),
    );
  }

  // Footnotes rendered as endnote-style block at bottom of document
  const footnotes = (input.footnotes || []).filter((f) => f.text.trim().length > 0);
  if (footnotes.length > 0) {
    bodyParagraphs.push(emptyP());
    bodyParagraphs.push(new Paragraph({
      border: { top: { style: BorderStyle.SINGLE, size: 6, color: "000000", space: 4 } },
      children: [run("")],
    }));
    footnotes.forEach((f) => {
      bodyParagraphs.push(new Paragraph({
        children: [
          run(`${f.id}`, { superscript: true, size: 20 }),
          run(" "),
          run(f.text, { size: 20 }),
        ],
      }));
    });
  }

  return new Document({
    styles: {
      default: { document: { run: { font: FONT, size: SIZE } } },
    },
    numbering: {
      config: [
        {
          reference: "pl-bullets",
          levels: [0, 1, 2].map((lvl) => ({
            level: lvl,
            format: LevelFormat.BULLET,
            text: "\u2022",
            alignment: AlignmentType.LEFT,
            style: { paragraph: { indent: { left: 720 * (lvl + 1), hanging: 360 } } },
          })),
        },
        {
          reference: "pl-numbers",
          levels: [0, 1, 2].map((lvl) => ({
            level: lvl,
            format: LevelFormat.DECIMAL,
            text: `%${lvl + 1}.`,
            alignment: AlignmentType.LEFT,
            style: { paragraph: { indent: { left: 720 * (lvl + 1), hanging: 360 } } },
          })),
        },
      ],
    },
    sections: [
      {
        properties: {
          page: {
            size: { width: 12240, height: 15840, orientation: PageOrientation.PORTRAIT },
            margin: { top: 1440, right: 1440, bottom: 1440, left: 1440 },
          },
        },
        footers: {
          default: new Footer({
            children: [buildFooterTable(input.footerLeft, input.footerCenter, input.footerRight)],
          }),
        },
        children: [
          p(headerLine1, { bold: true, align: AlignmentType.CENTER }),
          p(headerLine2, { bold: true, align: AlignmentType.CENTER }),
          emptyP(),
          captionTable,
          ...bodyParagraphs,
        ],
      },
    ],
  });
}

export async function downloadPleading(input: PleadingInput, filename: string) {
  const doc = buildPleadingDoc(input);
  const blob = await Packer.toBlob(doc);
  saveAs(blob, filename.endsWith(".docx") ? filename : `${filename}.docx`);
}

// ---------- Generic template (custom fields) ----------

export interface GenericDocInput {
  title?: string;
  body: string; // Already merged (fields substituted)
  fontFamily?: string;
  fontSizePt?: number;
}

export async function downloadGeneric(input: GenericDocInput, filename: string) {
  const font = input.fontFamily || "Bookman Old Style";
  const size = (input.fontSizePt || 12) * 2;

  const mkP = (text: string, bold = false, center = false) =>
    new Paragraph({
      alignment: center ? AlignmentType.CENTER : undefined,
      children: [new TextRun({ text, bold, font, size })],
    });

  const children: Paragraph[] = [];
  if (input.title) {
    children.push(mkP(input.title, true, true));
    children.push(new Paragraph({ children: [new TextRun({ text: "", font, size })] }));
  }
  input.body.split("\n").forEach((line) => children.push(mkP(line)));

  const doc = new Document({
    styles: { default: { document: { run: { font, size } } } },
    sections: [
      {
        properties: {
          page: {
            size: { width: 12240, height: 15840 },
            margin: { top: 1440, right: 1440, bottom: 1440, left: 1440 },
          },
        },
        children,
      },
    ],
  });

  const blob = await Packer.toBlob(doc);
  saveAs(blob, filename.endsWith(".docx") ? filename : `${filename}.docx`);
}