sesame oracle: explicit platform, cache fallback

docs/user_guide.md

@@ -113,6 +113,32 @@ simurg export finalreport --bpm M.bpm --csv M.csv --egt C.egt --gtcs run/gtc --o
 Global logging options on every command: `--quiet`, `--log-level`, `--log-json` (JSON Lines on stderr), `--debug`.
 Run `simurg COMMAND --help` for the full list.
 
+## Methylation arrays
+
+`simurg methyl qc` runs control-probe QC and a signal summary for Infinium methylation arrays (EPIC v1/v2, MSA,
+custom designs) from IDATs and the methylation CSV manifest (spec MET-001 … MET-018). It is a QC tool: there is no
+differential-methylation analysis.
+
+```bash
+simurg methyl qc --manifest infinium-methylationepic-v-1-0-b5-manifest-file.csv --idats idats/ \
+    --sheet SampleSheet.csv --out run/methyl --profile auto
+```
+
+* 21 control metrics (staining, extension, hybridization, target removal I/II, bisulfite conversion I/II with their
+  background ratios, specificity I/II, non-polymorphic, restoration); thresholds from the `methylation_epic` /
+  `methylation_msa` profiles (`auto` picks by manifest name), `--config` or `--threshold KEY=VALUE`.
+* Per sample: detection p-values (pOOBAH: out-of-band Infinium I signal and negative controls), noob background
+  correction, dye-bias correction (`--dye-bias linear|nonlinear`), β = M/(M+U+α) (`--beta-offset`, default 0) and
+  M-values.
+* `pass_qc` = every enabled, evaluable metric passes; `--min-prop-passing X` also requires that fraction of probes
+  to pass detection (`--pval-threshold`, default 0.05).
+* Outputs: `methyl_qc_summary.tsv/.xlsx/.html` (detection histogram and a β PCA coloured by `Sample_Group`),
+  `samples/<id>/<id>_cgs.tsv.gz` (probe_id, beta, m_value, detection_p), `<id>_ctrl.tsv.gz`, `pcs.tsv.gz`,
+  `probes.tsv`/`controls.tsv` (the manifest in the open-source toolkits' layout; also written by
+  `simurg methyl convert-manifest`), and `controls_raw.tsv`/`controls_qc.tsv`, so `simurg qc report` accepts the folder.
+* Sample sheets may use `Sentrix_ID`/`Sentrix_Position` (minfi/sesame convention) as key columns.
+* `simurg qc controls --array-type methylation --csv MANIFEST.csv` computes only the control tables.
+
 ## Presets and reproducibility
 
 * `--preset current` (default): normalization 1.2.0, sex rule 2, GTC v5 — the current vendor software behaviour.
@@ -185,7 +211,7 @@ A nightly differential run (`scripts/nightly.py`) re-checks these against the or
 * Speed: with the compiled kernels a GSA sample takes ~1.1 s on a Raspberry Pi 5 core (pure Python ~3.4 s); see
   `docs/validation/P9.md` for server numbers and thread scaling. Loading a manifest/cluster file is a fixed cost
   per run (GSA ~5 s, Omni2.5 ~15 s on the Pi).
-* Methylation arrays: control-probe QC only.
+* Methylation arrays: control-probe QC, detection and β values only (no differential analysis).
 
 ## Troubleshooting
 

scripts/v2/sesame_oracle.R

@@ -20,9 +20,12 @@ inband <- function(s) {
   list(m = m, u = u)
 }
 for (prefix in args[-(1:3)]) {
-  sdf <- tryCatch(readIDATpair(prefix, manifest = mft, controls = controls, min_beads = 3),
+  read <- function() readIDATpair(prefix, platform = "EPIC", manifest = mft, controls = controls, min_beads = 3)
-                  error = function(e) { message("min_beads not accepted: ", conditionMessage(e));
+  sdf <- tryCatch(read(), error = function(e) {
-                                        readIDATpair(prefix, manifest = mft, controls = controls) })
+    message("first read failed (", conditionMessage(e), "); caching idatSignature and retrying")
+    sesameDataCache("idatSignature")
+    read()
+  })
   pv <- pOOBAH(sdf, return.pval = TRUE)
   sn <- noob(sdf)
   ib <- inband(sn)