"""OCR 文档结果包的合成 fixtures(#34)。

全部**合成**: 保留 2026-10-21 实测的结构骨架(para_blocks 块类型、table/image 的嵌套
`blocks`、span 字段),一切识别文本替换为 `SYNTH-*` 占位——第三方论文内容许可不明、
医疗数据不入库(零业务假设 + P5),真实 ZIP 不提交。
"""

import io
import json
import zipfile

_BBOX = (10.0, 20.0, 110.0, 40.0)


def _span(content="SYNTH-TEXT", type_="text"):
    return {"type": type_, "content": content, "bbox": list(_BBOX), "score": 1.0}


def _text_block(content="SYNTH-TEXT", *, type_="text", bbox=_BBOX):
    return {
        "type": type_,
        "bbox": list(bbox),
        "index": 0,
        "lines": [{"bbox": list(bbox), "spans": [_span(content)]}],
    }


def _body(type_, spans, bbox=_BBOX):
    return {"type": type_, "bbox": list(bbox), "lines": [{"bbox": list(bbox), "spans": spans}]}


def _table_block(html="<table><tr><td>SYNTH-CELL</td></tr></table>", extra_subs=()):
    body = _body("table_body", [{"type": "table", "html": html, "image_path": "synth.jpg"}])
    return {"type": "table", "bbox": list(_BBOX), "index": 1, "blocks": [*extra_subs, body]}


def _image_block():
    body = _body("image_body", [{"type": "image", "image_path": "synth.jpg"}])
    return {"type": "image", "bbox": list(_BBOX), "index": 2, "blocks": [body]}


def _page(blocks=None, *, page_idx=0, page_size=(612.0, 792.0), **extra):
    page = {"page_idx": page_idx, "page_size": list(page_size), "discarded_blocks": []}
    if blocks is not None:
        page["para_blocks"] = blocks
    page.update(extra)
    return page


def _package(
    pages=None,
    *,
    md="# synth\n",
    middle=None,
    middle_name="doc_middle.json",
    md_name=None,
    extra=(),
):
    """组装结果包。`middle` 给原始 bytes 时原样写入;`md_name` 默认由 middle 名配对。"""
    if middle is None:
        middle = json.dumps({"pdf_info": pages if pages is not None else [_page([])]}).encode()
    if md_name is None:
        md_name = middle_name[: -len("_middle.json")] + ".md"
    buf = io.BytesIO()
    with zipfile.ZipFile(buf, "w") as zf:
        zf.writestr(middle_name, middle)
        if md is not None:
            zf.writestr(md_name, md if isinstance(md, bytes) else md.encode())
        for name, data in extra:
            zf.writestr(name, data)
    return buf.getvalue()