diff --git a/tests/test_viewer_helpers.py b/tests/test_viewer_helpers.py
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+++ b/tests/test_viewer_helpers.py
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+"""Tests unitaires pour src/viewer/helpers.py.
+
+Couvre : filtres Jinja2, helpers de statistiques, fonctions utilitaires.
+Pas de dépendance à Ollama ni au système de fichiers (sauf tmpdir).
+"""
+
+from __future__ import annotations
+
+import re
+from collections import Counter
+from unittest.mock import patch, MagicMock
+
+import pytest
+from markupsafe import Markup
+
+from src.config import (
+    DossierMedical,
+    Diagnostic,
+    DPSelection,
+    DPCandidate,
+    ActeCCAM,
+    CodeDecision,
+    GHMEstimation,
+    VetoReport,
+    VetoIssue,
+    CompletudeDossier,
+    ControleCPAM,
+    FinancialImpact,
+    Sejour,
+)
+from src.viewer.helpers import (
+    compute_group_stats,
+    compute_dashboard_stats,
+    compute_dim_synthesis,
+    confidence_badge,
+    confidence_label,
+    severity_badge,
+    cma_level_badge,
+    format_duration,
+    format_dossier_name,
+    format_doc_name,
+    decision_badge,
+    format_cpam_text,
+    human_where,
+    _date_to_iso,
+    _sort_qc_alerts,
+    _compute_jours_restants,
+)
+
+
+# ── Helpers ────────────────────────────────────────────────────────────
+
+
+def _item(dossier: DossierMedical, path_rel: str = "test/file.json") -> dict:
+    """Crée un item de scan_dossiers minimal."""
+    return {"name": "file", "path_rel": path_rel, "dossier": dossier}
+
+
+def _diag(
+    texte: str = "Diagnostic",
+    code: str | None = None,
+    confidence: str | None = None,
+    est_cma: bool | None = None,
+    decision: CodeDecision | None = None,
+    cim10_final: str | None = None,
+) -> Diagnostic:
+    return Diagnostic(
+        texte=texte,
+        cim10_suggestion=code,
+        cim10_confidence=confidence,
+        est_cma=est_cma,
+        cim10_decision=decision,
+        cim10_final=cim10_final,
+    )
+
+
+# ===================================================================
+# confidence_badge / confidence_label
+# ===================================================================
+
+
+class TestConfidenceBadge:
+    def test_high(self):
+        result = confidence_badge("high")
+        assert isinstance(result, Markup)
+        assert "Haute" in result
+        assert "#16a34a" in result
+
+    def test_medium(self):
+        result = confidence_badge("medium")
+        assert "Moyenne" in result
+
+    def test_low(self):
+        result = confidence_badge("low")
+        assert "Basse" in result
+        assert "#dc2626" in result
+
+    def test_none_returns_empty(self):
+        assert confidence_badge(None) == ""
+
+    def test_empty_string_returns_empty(self):
+        assert confidence_badge("") == ""
+
+    def test_unknown_value_uses_default_colors(self):
+        result = confidence_badge("unknown")
+        assert "unknown" in result
+        assert "#6b7280" in result  # default foreground
+
+
+class TestConfidenceLabel:
+    @pytest.mark.parametrize("value,expected", [
+        ("high", "Haute"),
+        ("medium", "Moyenne"),
+        ("low", "Basse"),
+        (None, ""),
+        ("", ""),
+        ("autre", "autre"),
+    ])
+    def test_labels(self, value, expected):
+        assert confidence_label(value) == expected
+
+
+# ===================================================================
+# cma_level_badge
+# ===================================================================
+
+
+class TestCmaLevelBadge:
+    def test_none_returns_empty(self):
+        assert cma_level_badge(None) == ""
+
+    def test_zero_returns_empty(self):
+        assert cma_level_badge(0) == ""
+
+    def test_negative_returns_empty(self):
+        assert cma_level_badge(-1) == ""
+
+    @pytest.mark.parametrize("level", [1, 2, 3, 4])
+    def test_valid_levels(self, level):
+        result = cma_level_badge(level)
+        assert isinstance(result, Markup)
+        assert f"CMA {level}" in result
+
+    def test_level_above_4_capped(self):
+        """Un niveau > 4 est cappé à 4."""
+        result = cma_level_badge(5)
+        assert "CMA 4" in result
+
+
+# ===================================================================
+# format_dossier_name / format_doc_name
+# ===================================================================
+
+
+class TestFormatDossierName:
+    def test_racine(self):
+        assert format_dossier_name("racine") == "Non classés"
+
+    def test_normal_name(self):
+        assert format_dossier_name("190_23139234") == "190_23139234"
+
+
+class TestFormatDocName:
+    @pytest.mark.parametrize("name,expected", [
+        ("190_fusionne_cim10", "Fusionné"),
+        ("CRH_23139234_cim10", "CRH"),
+        ("CRO_23139234_cim10", "CRO"),
+        ("crh_23139234", "CRH"),
+        ("trackare-01295620", "Trackare"),
+        ("ANAPATH_23103383", "Anapath"),
+        ("some_other_doc", "some_other_doc"),
+    ])
+    def test_doc_names(self, name, expected):
+        assert format_doc_name(name) == expected
+
+
+# ===================================================================
+# decision_badge
+# ===================================================================
+
+
+class TestDecisionBadge:
+    def test_none_returns_empty(self):
+        assert decision_badge(None) == ""
+
+    def test_keep_returns_empty(self):
+        """KEEP n'a pas de badge (cas par défaut)."""
+        dec = CodeDecision(action="KEEP")
+        assert decision_badge(dec) == ""
+
+    @pytest.mark.parametrize("action,label", [
+        ("DOWNGRADE", "Rétrogradé"),
+        ("REMOVE", "Supprimé"),
+        ("RULED_OUT", "Écarté"),
+        ("NEED_INFO", "Preuve manquante"),
+        ("PROMOTE_DP", "Promu en DP"),
+    ])
+    def test_action_labels(self, action, label):
+        dec = CodeDecision(action=action)
+        result = decision_badge(dec)
+        assert label in result
+
+    def test_dict_input(self):
+        """Accepte un dict en plus d'un CodeDecision."""
+        result = decision_badge({"action": "REMOVE"})
+        assert "Supprimé" in result
+
+    def test_dict_keep(self):
+        result = decision_badge({"action": "KEEP"})
+        assert result == ""
+
+    def test_unknown_action(self):
+        """Action inconnue affiche le texte brut."""
+        result = decision_badge({"action": "CUSTOM_ACTION"})
+        assert "CUSTOM_ACTION" in result
+
+
+# ===================================================================
+# human_where
+# ===================================================================
+
+
+class TestHumanWhere:
+    @pytest.mark.parametrize("value,expected", [
+        (None, "Global"),
+        ("", "Global"),
+        ("diagnostic_principal", "Diagnostic Principal"),
+        ("diagnostics_associes", "Diagnostics Associés"),
+        ("sejour", "Séjour"),
+        ("diagnostics_associes[0]", "DAS n°1"),
+        ("diagnostics_associes[5]", "DAS n°6"),
+        ("actes_ccam[0]", "Acte n°1"),
+        ("actes_ccam[2]", "Acte n°3"),
+        ("autre_chose", "autre_chose"),
+    ])
+    def test_conversions(self, value, expected):
+        assert human_where(value) == expected
+
+
+# ===================================================================
+# _date_to_iso
+# ===================================================================
+
+
+class TestDateToIso:
+    def test_valid_date(self):
+        assert _date_to_iso("15/03/2025") == "2025-03-15"
+
+    def test_invalid_format(self):
+        assert _date_to_iso("2025-03-15") == ""
+
+    def test_empty_string(self):
+        assert _date_to_iso("") == ""
+
+    def test_single_part(self):
+        assert _date_to_iso("15") == ""
+
+
+# ===================================================================
+# _sort_qc_alerts
+# ===================================================================
+
+
+class TestSortQcAlerts:
+    def test_critical_first(self):
+        alerts = [
+            "Recommandation : ajouter un DAS",
+            "Erreur critique : code invalide",
+            "Code justifié solidement",
+        ]
+        sorted_alerts = _sort_qc_alerts(alerts)
+        assert sorted_alerts[0] == "Erreur critique : code invalide"
+        assert sorted_alerts[-1] == "Code justifié solidement"
+
+    def test_empty_list(self):
+        assert _sort_qc_alerts([]) == []
+
+    def test_dp_prioritized_within_tier(self):
+        """Les alertes mentionnant le DP sont priorisées dans leur tier."""
+        alerts = [
+            "Redondance dans DAS",
+            "Redondance DP diagnostic principal suspect",
+        ]
+        sorted_alerts = _sort_qc_alerts(alerts)
+        assert "DP" in sorted_alerts[0] or "diagnostic principal" in sorted_alerts[0]
+
+
+# ===================================================================
+# _compute_jours_restants
+# ===================================================================
+
+
+class TestComputeJoursRestants:
+    def test_no_date(self):
+        ctrl = MagicMock()
+        ctrl.date_limite_reponse = None
+        assert _compute_jours_restants(ctrl) is None
+
+    def test_invalid_date(self):
+        ctrl = MagicMock()
+        ctrl.date_limite_reponse = "not-a-date"
+        assert _compute_jours_restants(ctrl) is None
+
+    def test_valid_date_returns_int(self):
+        ctrl = MagicMock()
+        ctrl.date_limite_reponse = "15/03/2030"
+        result = _compute_jours_restants(ctrl)
+        assert isinstance(result, int)
+        assert result > 0  # well into the future
+
+
+# ===================================================================
+# compute_group_stats
+# ===================================================================
+
+
+class TestComputeGroupStats:
+    def test_empty_items(self):
+        stats = compute_group_stats([])
+        assert stats == {"das_count": 0, "alertes_count": 0, "actes_count": 0, "cma_count": 0}
+
+    def test_cma_counted_on_dp(self):
+        """CMA sur le DP est compté."""
+        d = DossierMedical(
+            diagnostic_principal=_diag("DP", "K85.9", est_cma=True),
+        )
+        stats = compute_group_stats([_item(d)])
+        assert stats["cma_count"] == 1
+
+    def test_multiple_items(self):
+        d1 = DossierMedical(
+            diagnostics_associes=[_diag("DAS1", "I10", est_cma=True)],
+            actes_ccam=[ActeCCAM(texte="Acte1")],
+            alertes_codage=["Alerte"],
+        )
+        d2 = DossierMedical(
+            diagnostics_associes=[_diag("DAS2", "E11.9"), _diag("DAS3", "J18.9", est_cma=True)],
+        )
+        stats = compute_group_stats([_item(d1), _item(d2)])
+        assert stats["das_count"] == 3
+        assert stats["actes_count"] == 1
+        assert stats["alertes_count"] == 1
+        assert stats["cma_count"] == 2
+
+
+# ===================================================================
+# compute_dashboard_stats
+# ===================================================================
+
+
+class TestComputeDashboardStats:
+    def test_empty_groups(self):
+        stats = compute_dashboard_stats({})
+        assert stats["total_dossiers"] == 0
+        assert stats["total_fichiers"] == 0
+        assert stats["top_codes"] == []
+        assert stats["processing_time_avg"] == 0
+
+    def test_single_dossier(self):
+        d = DossierMedical(
+            diagnostic_principal=_diag("DP", "K85.9", confidence="high"),
+            diagnostics_associes=[_diag("DAS", code="I10")],
+            actes_ccam=[ActeCCAM(texte="Acte")],
+            alertes_codage=["Alerte"],
+            processing_time_s=10.5,
+        )
+        groups = {"grp1": [_item(d)]}
+        stats = compute_dashboard_stats(groups)
+        assert stats["total_dossiers"] == 1
+        assert stats["total_fichiers"] == 1
+        assert stats["total_das"] == 1
+        assert stats["total_actes"] == 1
+        assert stats["total_alertes"] == 1
+        assert stats["processing_time_avg"] == 10.5
+
+    def test_dp_validity_absent_when_no_dp(self):
+        d = DossierMedical()
+        groups = {"grp": [_item(d)]}
+        stats = compute_dashboard_stats(groups)
+        assert stats["dp_validity"].get("absent", 0) == 1
+
+    def test_ghm_types_counted(self):
+        d = DossierMedical(
+            ghm_estimation=GHMEstimation(type_ghm="C", severite=3),
+        )
+        groups = {"grp": [_item(d)]}
+        stats = compute_dashboard_stats(groups)
+        assert stats["ghm_types"].get("C") == 1
+        assert stats["severity_dist"].get(3) == 1
+
+
+# ===================================================================
+# compute_dim_synthesis
+# ===================================================================
+
+
+class TestComputeDimSynthesis:
+    def test_empty_groups(self):
+        result = compute_dim_synthesis({})
+        assert result["dp"]["total"] == 0
+        assert result["das"]["total"] == 0
+        assert result["veto"]["avg_score"] == 0
+
+    def test_dp_confirmed(self):
+        d = DossierMedical(
+            dp_final=DPSelection(
+                chosen_code="K85.9",
+                verdict="CONFIRMED",
+                confidence="high",
+                evidence=["Test evidence"],
+            ),
+        )
+        groups = {"grp": [_item(d)]}
+        result = compute_dim_synthesis(groups)
+        assert result["dp"]["total"] == 1
+        assert result["dp"]["confirmed"] == 1
+
+    def test_dp_review_creates_alert(self):
+        d = DossierMedical(
+            dp_final=DPSelection(
+                chosen_code="R10.4",
+                verdict="REVIEW",
+                confidence="medium",
+                reason="Ambigu",
+                evidence=[],
+            ),
+        )
+        groups = {"grp": [_item(d)]}
+        result = compute_dim_synthesis(groups)
+        assert result["dp"]["review"] == 1
+        assert len(result["alertes"]["review"]) == 1
+
+    def test_das_decisions_counted(self):
+        d = DossierMedical(
+            diagnostics_associes=[
+                _diag("DAS1", "I10", decision=CodeDecision(action="KEEP")),
+                _diag("DAS2", "D69.6", decision=CodeDecision(action="RULED_OUT")),
+                _diag("DAS3", "D50", decision=CodeDecision(action="DOWNGRADE", final_code="D64.9")),
+                _diag("DAS4", "Z87.1", decision=CodeDecision(action="REMOVE")),
+            ],
+        )
+        groups = {"grp": [_item(d)]}
+        result = compute_dim_synthesis(groups)
+        assert result["das"]["total"] == 4
+        assert result["das"]["kept"] == 1
+        assert result["das"]["ruled_out"] == 1
+        assert result["das"]["downgraded"] == 1
+        assert result["das"]["removed"] == 1
+
+    def test_das_no_decision_counted_as_kept(self):
+        d = DossierMedical(
+            diagnostics_associes=[_diag("DAS", "I10")],  # no decision
+        )
+        groups = {"grp": [_item(d)]}
+        result = compute_dim_synthesis(groups)
+        assert result["das"]["kept"] == 1
+
+    def test_veto_report_aggregated(self):
+        d = DossierMedical(
+            veto_report=VetoReport(
+                verdict="FAIL",
+                score_contestabilite=40,
+                issues=[
+                    VetoIssue(veto="VETO-01", severity="HARD", where="dp", message="test"),
+                ],
+            ),
+        )
+        groups = {"grp": [_item(d)]}
+        result = compute_dim_synthesis(groups)
+        assert result["veto"]["avg_score"] == 40
+        assert result["veto"]["distribution"].get("FAIL") == 1
+        assert len(result["alertes"]["fail"]) == 1
+
+    def test_completude_indefendable(self):
+        d = DossierMedical(
+            completude=CompletudeDossier(
+                verdict_global="indefendable",
+                score_global=20,
+                documents_manquants=["CRO", "Anapath"],
+            ),
+        )
+        groups = {"grp": [_item(d)]}
+        result = compute_dim_synthesis(groups)
+        assert result["completude"]["distribution"].get("indefendable") == 1
+        assert len(result["alertes"]["indefendable"]) == 1
+
+    def test_taux_modification_zero_when_no_das(self):
+        result = compute_dim_synthesis({})
+        assert result["das"]["taux_modification"] == 0
+
+    def test_cpam_impact(self):
+        d = DossierMedical(
+            controles_cpam=[
+                ControleCPAM(
+                    numero_ogc=1,
+                    financial_impact=FinancialImpact(
+                        impact_estime_euros=1500,
+                        priorite="haute",
+                    ),
+                    validation_dim="valide",
+                ),
+            ],
+        )
+        groups = {"grp": [_item(d)]}
+        result = compute_dim_synthesis(groups)
+        assert result["cpam"]["total"] == 1
+        assert result["cpam"]["impact_total"] == 1500
+        assert result["cpam"]["by_priority"].get("haute") == 1
+        assert result["cpam"]["by_status"].get("valide") == 1
+
+
+# ===================================================================
+# format_cpam_text (additional edge cases beyond test_viewer.py)
+# ===================================================================
+
+
+class TestFormatCpamTextExtra:
+    def test_blank_lines_produce_br(self):
+        result = format_cpam_text("Line 1\n\nLine 2")
+        assert "<br>" in result
+
+    def test_list_closed_at_end(self):
+        """A list not followed by text should still be closed."""
+        result = format_cpam_text("- Item 1\n- Item 2")
+        assert result.count("<ul") == 1
+        assert result.count("</ul>") == 1