"""Generate the Colsys 'Objednávka' order form as a PDF, replicating the
ERP layout, followed by the line-items table. Output is one combined PDF.

Layout reference: samples/Objednavky_TU_2025_1576.PDF
"""
from __future__ import annotations

import os

from reportlab.lib.pagesizes import A4
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont
from reportlab.pdfgen import canvas

PAGE_W, PAGE_H = A4  # 595.27 x 841.89 pt
L = 40            # left margin
R = PAGE_W - 40   # right margin

# ── Fonts (DejaVu = full Czech diacritics) ──
_FONT, _BOLD = "Helvetica", "Helvetica-Bold"
for name, path in (
    ("DejaVu", "/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf"),
    ("DejaVu-Bold", "/usr/share/fonts/truetype/dejavu/DejaVuSans-Bold.ttf"),
):
    if os.path.exists(path):
        try:
            pdfmetrics.registerFont(TTFont(name, path))
        except Exception:
            pass
if "DejaVu" in pdfmetrics.getRegisteredFontNames():
    _FONT, _BOLD = "DejaVu", "DejaVu-Bold"


def _ty(y: float) -> float:
    """Top-origin → reportlab bottom-origin."""
    return PAGE_H - y


def _wrap(c, text, font, size, max_w):
    text = str(text or "")
    if not text:
        return [""]
    out, line = [], ""
    for word in text.split(" "):
        trial = (line + " " + word).strip()
        if pdfmetrics.stringWidth(trial, font, size) <= max_w or not line:
            line = trial
        else:
            out.append(line)
            line = word
    out.append(line)
    return out


def _money(v) -> str:
    if v is None or v == "":
        return ""
    try:
        s = f"{float(v):,.2f}"
        # CZ formatting: 1 234,56
        return s.replace(",", " ").replace(".", ",")
    except (TypeError, ValueError):
        return str(v)


def _qty(v) -> str:
    if v is None or v == "":
        return ""
    try:
        f = float(v)
        return str(int(f)) if f.is_integer() else f"{f:.3f}".rstrip("0").rstrip(".").replace(".", ",")
    except (TypeError, ValueError):
        return str(v)


# ─────────────────────────── page 1: the form ───────────────────────────

def _party_box(c, x0, x1, top, label, party):
    """Draw one bordered party box (Objednatel / Dodavatel): the label on
    its own line, a blank row, then the company name + address below."""
    name = party.get("name") or ""
    addr = party.get("address") or ""
    parts = [p.strip() for p in addr.split(",") if p.strip()]
    ico, dic = party.get("ico") or "", party.get("dic") or ""
    email = party.get("email")
    c.setFont(_FONT, 8)
    c.drawString(x0 + 6, _ty(top + 14), label)
    # blank row, then the company block on its own lines
    yy = top + 36
    c.setFont(_BOLD, 9.5)
    c.drawString(x0 + 6, _ty(yy), name)
    yy += 13
    c.setFont(_FONT, 8)
    for ln in parts:
        c.drawString(x0 + 6, _ty(yy), ln)
        yy += 11
    idline = "    ".join(s for s in (f"IČO: {ico}" if ico else "",
                                     f"DIČ: {dic}" if dic else "") if s)
    if idline:
        c.drawString(x0 + 6, _ty(yy + 2), idline)
        yy += 13
    if email:
        c.drawString(x0 + 6, _ty(yy + 2), f"e-mail: {email}")
        yy += 12
    return yy


def _kv_two(c, y, lx, ll, lv, rx, rl, rv):
    c.setFont(_FONT, 8)
    c.drawString(lx, _ty(y), ll)
    c.setFont(_BOLD, 8)
    c.drawString(lx + 82, _ty(y), str(lv or ""))
    c.setFont(_FONT, 8)
    c.drawString(rx, _ty(y), rl)
    c.setFont(_BOLD, 8)
    c.drawString(rx + 92, _ty(y), str(rv or ""))


def _draw_form_page(c, o):
    objednatel = o.get("objednatel") or {}
    dodavatel = o.get("dodavatel") or {}
    # Terms may arrive flat on the order or nested under "terms".
    _terms = o.get("terms") or {}
    terms = {k: (o.get(k) if o.get(k) not in (None, "") else _terms.get(k))
             for k in ("zpusob_platby", "zpusob_odberu", "zpusob_dopravy",
                       "forma_objednavky", "termin_dodani", "fakturujte")}
    num = o.get("objednavka_number") or ""

    # Title (with top breathing room)
    c.setFont(_BOLD, 14)
    c.drawRightString(R, _ty(44), f"Objednávka: {num}")

    # ── Header: two party boxes (with space above the boxes) ──
    top = 78
    box_h = 104
    mid = 300
    c.setLineWidth(0.6)
    c.rect(L, _ty(top + box_h), R - L, box_h, stroke=1, fill=0)
    c.line(mid, _ty(top + box_h), mid, _ty(top))
    _party_box(c, L, mid, top, "Objednatel", objednatel)
    _party_box(c, mid, R, top, "Dodavatel", dodavatel)

    # ── Dodací a platební podmínky ──
    t2 = top + box_h
    h2 = 60
    c.rect(L, _ty(t2 + h2), R - L, h2, stroke=1, fill=0)
    c.setFont(_BOLD, 8)
    c.drawString(L + 4, _ty(t2 + 11), "Dodací a platební podmínky")
    yy = t2 + 26
    _kv_two(c, yy, L + 4, "Způsob platby:", terms.get("zpusob_platby"),
            mid + 4, "Forma objednávky:", terms.get("forma_objednavky"))
    _kv_two(c, yy + 12, L + 4, "Způsob odběru:", terms.get("zpusob_odberu") or "-",
            mid + 4, "Termín dodání:", terms.get("termin_dodani"))
    _kv_two(c, yy + 24, L + 4, "Způsob dopravy:", terms.get("zpusob_dopravy") or "-",
            mid + 4, "Fakturujte:", terms.get("fakturujte"))

    # ── Datum vystavení / Popis ──
    t3 = t2 + h2
    h3 = 22
    c.rect(L, _ty(t3 + h3), R - L, h3, stroke=1, fill=0)
    c.line(mid, _ty(t3 + h3), mid, _ty(t3))
    c.setFont(_FONT, 8)
    c.drawString(L + 4, _ty(t3 + 14), "Datum vystavení")
    c.setFont(_BOLD, 8)
    c.drawString(L + 95, _ty(t3 + 14), str(o.get("datum_vystaveni") or ""))
    c.setFont(_FONT, 8)
    c.drawString(mid + 4, _ty(t3 + 14), "Popis:")
    c.setFont(_BOLD, 8)
    c.drawString(mid + 50, _ty(t3 + 14), str(o.get("popis") or ""))

    # ── Sub-header: order no + page ──
    t4 = t3 + h3 + 16
    c.setFont(_BOLD, 9)
    c.drawString(L, _ty(t4), f"Objednávka: {num}")
    c.drawRightString(R, _ty(t4), "Strana: 1/1")
    c.setLineWidth(0.6)
    c.line(L, _ty(t4 + 4), R, _ty(t4 + 4))

    # ── Body fields ──
    y = t4 + 22
    def field(label, value, gap_after=14, bold_label=True):
        nonlocal y
        c.setFont(_BOLD if bold_label else _FONT, 8.5)
        c.drawString(L, _ty(y), label)
        lw = pdfmetrics.stringWidth(label + " ", _BOLD, 8.5)
        c.setFont(_FONT, 8.5)
        for i, ln in enumerate(_wrap(c, value, _FONT, 8.5, R - L - lw)):
            c.drawString(L + (lw if i == 0 else 0), _ty(y), ln)
            if i > 0:
                y += 11
        y += gap_after

    field("NÁZEV ZAKÁZKY:", o.get("nazev_zakazky"))
    field("KÓD ZAKÁZKY/NS:", o.get("kod_zakazky"), gap_after=20)
    field("TEXT:", o.get("text"))
    field("CENA CELKEM (bez DPH):", o.get("cena_celkem_text") or _money(o.get("cena_celkem")) + (" Kč" if o.get("cena_celkem") not in (None, "") else ""))
    field("TERMÍN DODÁNÍ:", o.get("termin_dodani_text"), gap_after=20)
    field("MÍSTO DODÁNÍ:", o.get("misto_dodani"))
    field("KONTAKTNÍ OSOBA V MÍSTĚ DODÁNÍ (jméno, tel, email):",
          o.get("kontaktni_osoba"), gap_after=20)
    field("SPLATNOST:", o.get("splatnost"))
    field("ZÁRUKA:", o.get("zaruka"))
    field("POZNÁMKA:", o.get("poznamka"))
    field("PŘÍLOHY:", o.get("prilohy"))

    _draw_footer(c, o)


def _draw_footer(c, o):
    fy = 135  # pt from the bottom of the page; block is drawn downward
    # Datum / Vystavil
    c.setFont(_FONT, 8)
    c.drawString(L, fy, "Datum:")
    c.drawString(360, fy, "Vystavil:")
    c.setFont(_BOLD, 8)
    c.drawString(L, fy - 12, str(o.get("datum_vystaveni") or ""))
    c.drawString(360, fy - 12, str(o.get("vystavil") or ""))
    c.setFont(_BOLD, 8)
    c.drawString(L, fy - 30, "Faktury zasílejte na email adresu: faktury@colsys.cz")
    legal = (
        "Dodavatel souhlasí a potvrzuje, že se seznámil jako: A) prodávající s "
        "Všeobecnými nákupními podmínkami (VNP), B) nebo jako zhotovitel s "
        "Všeobecnými smluvními podmínkami (VSP) společnosti Colsys s.r.o. platnými "
        "ke dni vystavení objednávky (viz http://www.colsys.cz/dokumenty-ke-stazeni). "
        "Ve fakturách uvádějte vždy číslo objednávky přesně (včetně velkých a malých "
        "písmen) a zasílejte je v elektronické formě emailem ve formátu isdoc nebo "
        "isdocx. Přílohou faktury je vždy odsouhlasený protokol o předání/převzetí "
        "(Dodací list, Předávací protokol, Zjišťovací protokol apod.)."
    )
    c.setFont(_FONT, 6.5)
    yy = fy - 44
    for ln in _wrap(c, legal, _FONT, 6.5, R - L):
        c.drawString(L, yy, ln)
        yy -= 8
    c.drawString(L, yy - 2,
                 "Zapsáno: odd.C, vl. 902 obchodního rejstříku vedeného u Městského soudu v Praze.")


# ─────────────────────────── items table ───────────────────────────

_COLS = [
    ("Název zboží", "name", 200, "left"),
    ("ID dodavatele", "supplier_id", 80, "left"),
    ("Množství", "quantity", 55, "right"),
    ("MJ", "unit", 35, "left"),
    ("J. cena", "unit_price", 70, "right"),
    ("Celkem", "total_price", 75, "right"),
]


def _draw_items(c, o, items):
    c.showPage()
    num = o.get("objednavka_number") or ""
    y = 50
    c.setFont(_BOLD, 12)
    c.drawString(L, _ty(y), "Položky objednávky")
    c.setFont(_FONT, 9)
    c.drawRightString(R, _ty(y), f"Objednávka: {num}")
    y += 22

    def header():
        nonlocal y
        x = L
        c.setFont(_BOLD, 8)
        c.setFillColorRGB(1, 1, 1)
        c.setStrokeColorRGB(0.15, 0.39, 0.92)
        c.setFillColorRGB(0.15, 0.39, 0.92)
        c.rect(L, _ty(y + 14), R - L, 16, stroke=0, fill=1)
        c.setFillColorRGB(1, 1, 1)
        for title, _k, w, align in _COLS:
            if align == "right":
                c.drawRightString(x + w - 4, _ty(y + 10), title)
            else:
                c.drawString(x + 4, _ty(y + 10), title)
            x += w
        c.setFillColorRGB(0, 0, 0)
        y += 18

    header()
    c.setFont(_FONT, 8)
    total = 0.0
    for it in items or []:
        # page break
        if y > PAGE_H - 80:
            c.showPage()
            y = 50
            header()
            c.setFont(_FONT, 8)
        name_lines = _wrap(c, it.get("name"), _FONT, 8, _COLS[0][2] - 6)
        row_h = max(12, len(name_lines) * 10 + 2)
        x = L
        for title, k, w, align in _COLS:
            if k == "name":
                for i, ln in enumerate(name_lines):
                    c.drawString(x + 4, _ty(y + 9 + i * 10), ln)
            else:
                v = it.get(k)
                if k in ("unit_price", "total_price"):
                    s = _money(v)
                elif k == "quantity":
                    s = _qty(v)
                else:
                    s = str(v or "")
                if align == "right":
                    c.drawRightString(x + w - 4, _ty(y + 9), s)
                else:
                    c.drawString(x + 4, _ty(y + 9), s)
            x += w
        c.setStrokeColorRGB(0.85, 0.85, 0.85)
        c.setLineWidth(0.4)
        c.line(L, _ty(y + row_h), R, _ty(y + row_h))
        y += row_h
        try:
            total += float(it.get("total_price") or 0)
        except (TypeError, ValueError):
            pass

    # total row
    y += 6
    c.setFont(_BOLD, 9)
    c.drawString(L + 4, _ty(y + 9), "Celkem bez DPH")
    c.drawRightString(R - 4, _ty(y + 9), _money(total) + " Kč")


def build_order_pdf(order: dict, items: list, out_path: str) -> str:
    c = canvas.Canvas(out_path, pagesize=A4)
    _draw_form_page(c, order)
    _draw_items(c, order, items)
    c.save()
    return out_path