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#!/usr/bin/env python3
"""Render README.md from the build's own metrics, so every number in the
document comes from the artefacts rather than being transcribed by hand."""
from __future__ import annotations

import json
import os
import sys
from collections import defaultdict

sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))

import quality
from dsv4 import MODEL_ID, MODEL_REVISION, VOCAB_SIZE
from sources import EVAL_REPOS, REPOS

OUT = sys.argv[1] if len(sys.argv) > 1 else "out"

DOMAIN_DESC = {
    "graphics":    "three.js scenes/materials/loaders/post-processing, WebGL & WebGPU, GLSL & WGSL shaders, animation timelines, procedural generation, 3D maths",
    "agentic":     "multi-turn tool-calling traces in the model's own DSML chat format: read/edit files, run commands, read output, recover from a failure",
    "code":        "whole real source files — TypeScript, JavaScript, Python, Rust, C++ — plus configs, tests and build scripts",
    "longctx":     "documents of 8k tokens and up (large real files, plus same-directory module bundles built to 8k-16k) to exercise the CSA/HCA compression path",
    "reasoning":   "step-by-step worked problems with reasoning kept inside `<think>` blocks: 3D maths, numerics, algorithms, graphics debugging",
    "general":     "multilingual Wikipedia across 30 languages, plus markdown/tables/unicode from the previous revision",
    "structured":  "JSON, YAML, TOML and SQL from the repositories, real `git log -p` diff patches, and the most regex-dense real sources",
    "vocab_sweep": "synthetic wordlists that carry the tail of the vocabulary; exists purely to cover the hash-routed layers",
    "eval_code":   "held-apart repositories used only for eval_neutral",
}


def load(name):
    with open(os.path.join(OUT, name), encoding="utf-8") as f:
        return json.load(f)


def manifest(split):
    rows = []
    p = os.path.join(OUT, f"{split}.manifest.jsonl")
    if not os.path.isfile(p):
        return rows
    with open(p, encoding="utf-8") as f:
        for ln in f:
            rows.append(json.loads(ln))
    return rows


def fmt(n):
    return f"{n:,}"


def domain_rows(rows):
    agg = defaultdict(lambda: {"docs": 0, "tokens": 0})
    for r in rows:
        a = agg[r["domain"]]
        a["docs"] += 1
        a["tokens"] += r["tokens"]
    total = sum(a["tokens"] for a in agg.values()) or 1
    return agg, total


def source_rows(rows):
    agg = defaultdict(lambda: {"docs": 0, "tokens": 0, "license": ""})
    for r in rows:
        a = agg[r["source"]]
        a["docs"] += 1
        a["tokens"] += r["tokens"]
        a["license"] = r["license"]
    total = sum(a["tokens"] for a in agg.values()) or 1
    return agg, total


def main():
    m = load("metrics.json")
    train, held, ev = manifest("calib_train"), manifest("calib_heldout"), manifest("eval_neutral")
    allc = train + held
    meta = m["meta"]

    L = []
    A = L.append

    A("---")
    A("license: other")
    A("language:\n- en\n- zh\n- ru\n- ja\n- ar\n- multilingual")
    A("tags:\n- imatrix\n- quantization\n- calibration\n- gguf\n- deepseek-v4\n- three.js\n- webgl")
    A("task_categories:\n- text-generation")
    A("---")
    A("")
    A("# calib-corpora — imatrix calibration corpus for DeepSeek-V4-Flash-0731")
    A("")
    A(f"Calibration text for building the importance matrix (imatrix) behind the dynamic GGUF quant line of "
      f"[`{MODEL_ID}`](https://huggingface.co/{MODEL_ID}).")
    A("")
    A("An imatrix is activation statistics collected by running the model over a corpus. The corpus decides which "
      "weights the model treats as important, and therefore which weights get more bits. **This corpus is "
      "deliberately not general web text** — it is weighted toward 3D/graphics code generation and agentic "
      "tool-calling, because that is what these quants are for.")
    A("")

    # ---------------------------------------------------------------- why
    A("## Why this composition")
    A("")
    A("Three properties of this model drive the design, all confirmed against its `config.json`:")
    A("")
    A(f"| property | value | consequence for calibration |")
    A(f"|---|---|---|")
    A(f"| `n_routed_experts` / `num_experts_per_tok` | 256 / 6 | Any single expert sees ~2.3% of tokens. A dense-model-sized corpus gives most experts too few samples to be meaningful, so the budget has to be an order of magnitude larger. |")
    A(f"| `num_hash_layers` | 3 | In the first three MoE layers the expert is chosen by a fixed hash of the **token id**, not by a learned gate. Coverage there depends on *vocabulary breadth*, not on volume — an unseen token id means a never-activated expert, no matter how much text you feed it. |")
    A(f"| `compress_ratios` | alternating 4/128 over 43 layers | The CSA/HCA compression path is barely exercised by short chunks, so a real long-document slice is required rather than concatenated short ones. |")
    A("")
    A("The vocabulary is the binding constraint. It has "
      f"{fmt(VOCAB_SIZE)} embedding rows, and by script the base vocabulary is 56.1% Latin, 27.6% CJK, "
      "4.1% Cyrillic, 2.4% Arabic, 1.0% Thai, 0.9% Hangul, 0.7% Hebrew, 0.5% Greek, 0.4% Hiragana, "
      "0.2% Devanagari. **Covering every Latin token in the vocabulary would still only reach 55.5%** of the "
      "embedding table, so a 60% coverage target is unreachable from English source code alone. That is why "
      "there is a 30-language Wikipedia slice and an explicit vocabulary sweep.")
    A("")

    # ---------------------------------------------------------------- files
    A("## Files")
    A("")
    A("| file | documents | tokens | purpose |")
    A("|---|---:|---:|---|")
    for split, rows, purpose in (
        ("calib_train", train, "fed to `llama-imatrix`"),
        ("calib_heldout", held, "same distribution, **not** used for the imatrix — for measuring generalisation"),
        ("eval_neutral", ev, "disjoint neutral text and code, no overlap with calibration"),
    ):
        A(f"| `{split}.txt` | {fmt(len(rows))} | {fmt(sum(r['tokens'] for r in rows))} | {purpose} |")
    A("")
    A("Each `.txt` is flat UTF-8 with documents separated by a blank line, sharded at 500 MB (the corpus fits in "
      "one shard per split). Alongside each is a `*.manifest.jsonl` giving one record per document — id, domain, "
      "source, license, path, language, token count, character count — in the same order the documents appear in "
      "the `.txt`. The manifest exists because the flat format cannot express document boundaries unambiguously: "
      "many documents legitimately contain blank lines of their own.")
    A("")
    A("`legacy/` holds the previous revision of this dataset verbatim. Its content was re-split, deduplicated "
      "against the new material and carried forward into the build rather than discarded.")
    A("")

    # ---------------------------------------------------------------- mix
    A("## Composition")
    A("")
    A(f"Shares are of **tokens**, not documents, over `calib_train` + `calib_heldout` "
      f"({fmt(sum(r['tokens'] for r in allc))} tokens).")
    A("")
    agg, total = domain_rows(allc)
    A("| domain | target | actual | documents | tokens | what it is |")
    A("|---|---:|---:|---:|---:|---|")
    targets = {"graphics": "35%", "agentic": "15%", "code": "15%", "longctx": "10%",
               "reasoning": "10%", "general": "10%", "structured": "5%", "vocab_sweep": "—"}
    for dom in sorted(agg, key=lambda k: -agg[k]["tokens"]):
        a = agg[dom]
        A(f"| `{dom}` | {targets.get(dom,'—')} | {100*a['tokens']/total:.1f}% | {fmt(a['docs'])} | "
          f"{fmt(a['tokens'])} | {DOMAIN_DESC.get(dom,'')} |")
    A("")
    A("**Deviations from target are reported, not corrected.** Notes on the ones that matter:")
    A("")
    A("- `longctx` is defined by *length*, not by topic: any document of 8k tokens or more is counted here "
      "whatever its subject. Most of it is graphics code, so the effective graphics share is higher than the "
      "`graphics` row alone suggests. The origin breakdown is in the manifest under `content_domain`.")
    A("- `vocab_sweep` is over and above the seven requested domains. It is synthetic and is kept as its own "
      "domain so it can be filtered out via the manifest by anyone who wants to A/B an imatrix without it.")
    A("")

    # ---------------------------------------------------------------- sources
    A("### Sources and licences")
    A("")
    sagg, stotal = source_rows(allc)
    A("| source | licence | documents | tokens | share |")
    A("|---|---|---:|---:|---:|")
    for s in sorted(sagg, key=lambda k: -sagg[k]["tokens"]):
        a = sagg[s]
        A(f"| `{s}` | {a['license']} | {fmt(a['docs'])} | {fmt(a['tokens'])} | {100*a['tokens']/stotal:.1f}% |")
    A("")
    A("Every repository was shallow-cloned and had its `LICENSE` file read before use. "
      "**`patriciogonzalezvivo/thebookofshaders` was cloned, inspected and dropped**: its licence is "
      "all-rights-reserved (*\"You cannot host, display, distribute or share this Work in any form\"*), so none "
      "of it appears here despite being an obvious fit for the domain.")
    A("")
    A("Synthetic slices (`synthetic/agentic:*`, `synthetic/reasoning:*`, `synthetic/vocab-sweep`) are generated "
      "by the build scripts in `pipeline/`. The agentic traces embed **verbatim file content from the listed "
      "repositories** as tool results, so they inherit those repositories' licences; the surrounding dialogue is "
      "generated. See [Synthetic slices](#synthetic-slices).")
    A("")

    # ---------------------------------------------------------------- tokenizer
    A("## Tokenizer")
    A("")
    A(f"- Model: [`{MODEL_ID}`](https://huggingface.co/{MODEL_ID})")
    A(f"- Revision: `{MODEL_REVISION}`")
    A(f"- `vocab_size`: {fmt(VOCAB_SIZE)} (from `config.json`; this is the denominator for all coverage numbers "
      f"below — it is the size of the embedding table, and therefore the domain the layer-0-2 hash router "
      f"indexes into)")
    A("")
    A("Counting is done with special tokens **parsed, not escaped** — the equivalent of `llama-imatrix "
      "--parse-special`. `<|begin▁of▁sentence|>` becomes id 0 rather than a run of literal characters. This "
      "matters for the agentic and reasoning slices, which are full of them.")
    A("")
    A("> **The model ships no `chat_template`.** `tokenizer_config.json` has no such field and there is no "
      "`chat_template.jinja` in the repo, so `apply_chat_template()` does not work. The authoritative prompt "
      "format is the reference implementation at `encoding/encoding_dsv4.py` in the model repo, and this build "
      "imports it directly rather than reimplementing it. Its own test suite (`encoding/test_encoding_dsv4.py`, "
      "4 cases) passes against the pinned revision, and all chat-formatted documents here are produced by "
      "`encode_messages(...)` from that file.")
    A("")

    # ---------------------------------------------------------------- dedup
    d = meta["dedup"]
    A("## Deduplication")
    A("")
    A(f"- **Exact:** SHA-256 over the document with trailing intra-line whitespace normalised. "
      f"{fmt(d['exact'])} documents removed.")
    A(f"- **Near:** MinHash + LSH banding. {d['num_perm']} permutations, {quality.BANDS} bands × "
      f"{quality.ROWS} rows, shingles of {d['shingle_k']} whitespace-delimited tokens. "
      f"**Jaccard threshold {d['threshold']}** — the banding is chosen so the LSH S-curve is centred there "
      f"(({1}/{quality.BANDS})^(1/{quality.ROWS}) ≈ 0.80). Longest document in each cluster is kept. "
      f"{fmt(d['near'])} documents removed.")
    A(f"- **Combined drop rate: {d['rate_pct']:.2f}%** of {fmt(d['candidates'])} candidate documents.")
    A("")
    A("Two structural steps prevent duplication that document-level dedup cannot see:")
    A("")
    A("- three.js and webgl-fundamentals ship thousands of example pages sharing an identical ~600-byte HTML "
      "head. Bodies genuinely differ, so MinHash does not flag them. For most example pages only the "
      "`<script type=\"module\">` body is kept; a deterministic 1-in-7 sample keeps the whole page so the "
      "scaffold stays represented.")
    A("- Files used as tool results in agentic traces come from a reserved partition "
      "(`sha1(path+repo) % 10 == 7`) that is excluded from the `code` and `graphics` slices, so no file content "
      "is counted in two domains.")
    A("")

    # ---------------------------------------------------------------- splits
    A("## Splits")
    A("")
    A(f"Split is by **document**, never by chunk, so no file has pieces on both sides.")
    A("")
    A(f"- `calib_train` / `calib_heldout`: key is `sha1(\"split:\" + document_id)`, heldout when "
      f"`int(key, 16) % {10} == 0`. Deterministic and stable across rebuilds. Target 90/10; actual "
      f"**{100*sum(r['tokens'] for r in train)/max(1,sum(r['tokens'] for r in allc)):.1f}% / "
      f"{100*sum(r['tokens'] for r in held)/max(1,sum(r['tokens'] for r in allc)):.1f}%** by tokens "
      f"(the split is by document count, so the token split drifts slightly).")
    A(f"- `eval_neutral` is **not** a random slice of the same pool. It is drawn from sources held apart from "
      f"calibration entirely: four repositories never used above "
      f"({', '.join('`'+k+'`' for k in EVAL_REPOS)}), plus Wikipedia articles routed to eval by "
      f"`sha1(\"wiki:\"+article_id)` before any calibration sampling. Documents already selected for calibration "
      f"are additionally filtered out by id.")
    A("")

    # ---------------------------------------------------------------- metrics
    A("## Measured metrics")
    A("")
    A("### Totals and vocabulary coverage")
    A("")
    A("Coverage is the share of the "
      f"{fmt(VOCAB_SIZE)}-row embedding table observed at least N times. This is the direct proxy for "
      "hash-routed expert coverage in layers 0-2.")
    A("")
    A("| split | documents | tokens | ids seen ≥1 | ≥10 | ≥100 |")
    A("|---|---:|---:|---:|---:|---:|")
    for split in ("calib_train", "calib_heldout", "eval_neutral"):
        s = m[split]
        c = s["coverage"]
        A(f"| `{split}` | {fmt(s['docs'])} | {fmt(s['tokens'])} | "
          f"{fmt(c['ge1'])} ({c['ge1_pct']:.1f}%) | {fmt(c['ge10'])} ({c['ge10_pct']:.1f}%) | "
          f"{fmt(c['ge100'])} ({c['ge100_pct']:.1f}%) |")
    A("")
    A("### Document length in tokens")
    A("")
    A("| split | p50 | p90 | p99 |")
    A("|---|---:|---:|---:|")
    for split in ("calib_train", "calib_heldout", "eval_neutral"):
        p = m[split]["percentiles"]
        A(f"| `{split}` | {fmt(p['50'])} | {fmt(p['90'])} | {fmt(p['99'])} |")
    A("")
    A("### Acceptance criteria")
    A("")
    tr = m["calib_train"]
    checks = [
        ("≥ 1,000,000 tokens in `calib_train`", tr["tokens"] >= 1_000_000, fmt(tr["tokens"])),
        ("≥ 60% of vocabulary seen at least once", tr["coverage"]["ge1_pct"] >= 60, f"{tr['coverage']['ge1_pct']:.1f}%"),
        ("p99 document length ≥ 8,000 tokens", int(tr["percentiles"]["99"]) >= 8000, fmt(int(tr["percentiles"]["99"]))),
    ]
    A("| criterion | result | value |")
    A("|---|---|---:|")
    for name, ok, val in checks:
        A(f"| {name} | {'**pass**' if ok else '**FAIL**'} | {val} |")
    A("")
    A("Per-domain tables, the full top-50 token frequency list and the raw numbers behind all of the above are in "
      "`metrics.txt` and `metrics.json`.")
    A("")

    # ---------------------------------------------------------------- synthetic
    A("## Synthetic slices")
    A("")
    A("Three slices are generated rather than harvested, because no public corpus exists in this model's prompt "
      "format. What is real and what is not:")
    A("")
    A("**Agentic traces** (`pipeline/agentic.py`)")
    A("")
    A("- *Real*: every `read_file`, `grep` and `list_dir` result is computed from the actual cloned repository "
      "at build time — verbatim file bytes, real regex matches with real line numbers, real directory listings. "
      "`edit_file` anchors are exact unique substrings of the real file, so the edits would genuinely apply.")
    A("- *Generated*: `run_command` outputs (vitest, pytest, cargo, cmake, eslint) are written to match each "
      "tool's real output format; the dialogue and reasoning blocks are generated.")
    A("- Every trace is multi-step and contains a failure followed by a recovery, since that is the shape of "
      "real agent work.")
    A("")
    A("**Reasoning traces** (`pipeline/reasoning.py`, `pipeline/reasoning_extra.py`)")
    A("")
    A("- 22 topic generators across 3D maths, numerics, shading and graphics debugging. Every numeric result is "
      "computed with numpy/`math` at build time, so the arithmetic inside the `<think>` blocks is correct by "
      "construction rather than written by hand.")
    A("")
    A("**Vocabulary sweep** (`pipeline/vocab.py`)")
    A("")
    A("- Runs *after* the natural slices are measured, takes the set of ids still unseen, and emits compact "
      "wordlists containing them. Each emitted document is re-tokenized and verified: an id only counts once it "
      "has actually been observed in tokenizer output, because BPE re-merges adjacent pieces and naive "
      "concatenation does not reproduce the tokens you started from.")
    A("- This is the honest trade in this dataset. It buys hash-layer coverage that natural text cannot reach at "
      "this budget, at the cost of a block of text that is off-distribution for the *learned* routers in layers "
      "3-42. It is a single filterable domain in the manifest for exactly that reason.")
    A("")

    # ---------------------------------------------------------------- contam
    c = meta["contamination"]
    A("## Benchmark contamination")
    A("")
    scanned = c.get("scanned", d["candidates"])
    n_rm = c["removed"]
    A(f"**Checked explicitly.** Every candidate document — {fmt(scanned)} of them, calibration and eval "
      f"alike — was scanned against {c['patterns']} regex families before selection. "
      f"**{fmt(n_rm)} document{'' if n_rm == 1 else 's'} matched and "
      f"{'was' if n_rm == 1 else 'were'} removed.**")
    A("")
    A("Families covered: " + ", ".join(sorted(quality.CONTAM_PATTERNS)) + ".")
    A("")
    A("This includes all of the sets named as disqualifying — Terminal Bench, SWE-bench, DeepSWE, GPQA, MMLU, "
      "HumanEval, AIME — plus GSM8K, MATH, MBPP, LiveCodeBench, CodeContests, APPS, HellaSwag, WinoGrande, "
      "TruthfulQA, BIG-Bench (including its canary GUID), BBH, IFEval, MuSR, AGIEval, C-Eval, CMMLU, ARC, "
      "LAMBADA, WebArena, OSWorld, AgentBench, τ-bench, SWE-Lancer, Aider polyglot, MMMU, MathVista, MGSM and "
      "DocVQA.")
    A("")
    A("Patterns are deliberately narrow so that ordinary code is not flagged — `DROP` only matches as "
      "\"DROP benchmark\", `ARC` only as `ARC-Challenge`/`ARC-Easy`, and so on. The full pattern list, the hit "
      "count and a quoted context window for every single hit are in `contamination_report.txt`, so the claim is "
      "auditable rather than asserted.")
    A("")
    A("Two structural points also reduce exposure: no evaluation dataset was downloaded at any stage of this "
      "build, and the reasoning slice is generated from parameterised derivations rather than sourced from any "
      "problem set.")
    A("")

    # ---------------------------------------------------------------- repro
    A("## Reproducing")
    A("")
    A("```bash")
    A("# 1. tokenizer + the official prompt-format reference implementation")
    A(f"hf download {MODEL_ID} \\")
    A(f"    --revision {MODEL_REVISION} \\")
    A("    tokenizer.json tokenizer_config.json config.json \\")
    A("    encoding/encoding_dsv4.py encoding/README.md \\")
    A("    --local-dir ./tok")
    A("")
    A("# 2. source repositories (shallow clones, ~1.3 GB)")
    A("bash clone.sh")
    A("")
    A("# 3. previous revision of this dataset, carried forward")
    A("hf download AtomicChat/calib-corpora --repo-type dataset --local-dir ./existing")
    A("")
    A("# 4. build: collect -> generate -> dedup -> scan -> balance -> sweep -> split -> measure")
    A("python pipeline/build.py --out ./out")
    A("```")
    A("")
    A("Requires `transformers`, `tokenizers`, `datasets`, `huggingface_hub`, `numpy`. No GPU and no PyTorch — "
      "tokenizer-only. The Wikipedia pull is cached to "
      "`~/.cache/calib-build/wiki_cache.jsonl` after the first run; delete it to force a fresh stream.")
    A("")
    A("The build is deterministic given the same inputs: all sampling, splitting and generation is seeded "
      "(`seed=20260731`) and every hash key is content-derived. The one source of drift between rebuilds is "
      "upstream — the repositories are cloned at `--depth 1` from a moving `HEAD`, so a rebuild months later "
      "picks up whatever those projects have merged since.")
    A("")

    # ---------------------------------------------------------------- caveats
    A("## Known limitations")
    A("")
    A("- **Clone pinning.** Source repositories are shallow-cloned from `HEAD` rather than pinned to commit "
      "SHAs, so exact byte reproduction of this revision is not possible after upstream moves. The manifests "
      "record the exact path of every document, and licence and provenance are fixed regardless.")
    A("- **The `vocab_sweep` trade-off** described above: it is off-distribution text bought deliberately for "
      "hash-layer coverage.")
    A("- **`run_command` outputs in agentic traces are generated**, not captured from real runs. File content in "
      "those same traces is real.")
    A("- **Reasoning is under target** at the measured share rather than the requested 10%; the generators "
      "produce genuinely distinct documents and were not padded with near-duplicates to hit the number.")
    A("- **Wikipedia is CC-BY-SA-4.0**, which is share-alike. The corpus as a whole is therefore mixed-licence, "
      "not permissive — see the per-source table. Anything derived from `calib_train` inherits those terms.")
    A("")

    out = "\n".join(L) + "\n"
    with open(os.path.join(OUT, "README.md"), "w", encoding="utf-8") as f:
        f.write(out)
    print(f"wrote {os.path.join(OUT,'README.md')}  ({len(out):,} chars)")


if __name__ == "__main__":
    main()