package matching

import (
	"context"
	"strings"
	"testing"
	"time"

	"github.com/google/uuid"
	"github.com/jackc/pgx/v5/pgtype"
	"github.com/shopspring/decimal"

	"github.com/missionworkforce/missionmatch/internal/modules/matching/engine"
	"github.com/missionworkforce/missionmatch/internal/platform/database/dbgen"
)

func dec(n int) decimal.Decimal { return decimal.NewFromInt(int64(n)) }

func TestProposalReadyGate(t *testing.T) {
	// Green with all certs held is the only YES.
	yes := proposalReady(engine.MatchResult{Band: engine.BandGreen, Total: dec(95), Certifications: dec(100)}, false)
	if yes.Value != "YES" {
		t.Fatalf("green plus certs must be YES, got %+v", yes)
	}

	// Green but a cert gap is REVIEW, and the reason names the missing certification (never a bare NO).
	certGap := proposalReady(engine.MatchResult{
		Band: engine.BandGreen, Total: dec(92), Certifications: dec(66),
		GapSummary: []string{"Missing required certification: CISSP"},
	}, false)
	if certGap.Value != "REVIEW" || !strings.Contains(certGap.Reason, "CISSP") {
		t.Fatalf("green with a cert gap must REVIEW citing the cert, got %+v", certGap)
	}

	// Below green is REVIEW with a readiness reason.
	below := proposalReady(engine.MatchResult{Band: engine.BandYellow, Total: dec(80), Certifications: dec(100)}, false)
	if below.Value != "REVIEW" || below.Reason == "" {
		t.Fatalf("below green must REVIEW with a reason, got %+v", below)
	}
}

func TestClearanceCellRendersStatusAndUnknown(t *testing.T) {
	asOf := time.Date(2026, 6, 24, 0, 0, 0, 0, time.UTC)
	date := func(y int) pgtype.Date {
		return pgtype.Date{Time: time.Date(y, 1, 1, 0, 0, 0, 0, time.UTC), Valid: true}
	}

	// Active Secret with a future expiry: shown as Active, SCI not eligible, investigation year present.
	active := dbgen.Candidate{
		ID: uuid.New(), ClearanceLevel: "secret", ClearancePoly: "none", ClearanceStatus: "active",
		ClearanceGrantedAt: date(2022), ClearanceExpiresAt: date(2030),
	}
	a := clearanceCell(active, ClearanceFactsFrom(active, nil), asOf)
	if !a.SciKnown || a.Status != "Active" || a.SciEligible || a.InvestigationYear != "2022" {
		t.Fatalf("active Secret rendered wrong: %+v", a)
	}

	// A clearance whose expiry has passed must render Expired, never a confident Active.
	lapsed := dbgen.Candidate{
		ID: uuid.New(), ClearanceLevel: "ts_sci", ClearancePoly: "full_scope", ClearanceStatus: "active",
		ClearanceExpiresAt: date(2024),
	}
	l := clearanceCell(lapsed, ClearanceFactsFrom(lapsed, nil), asOf)
	if l.Status != "Expired" {
		t.Fatalf("a lapsed clearance must show Expired, got %q", l.Status)
	}

	// Unknown clearance (sourced External lead): rendered as Unknown, not SciKnown, never blank.
	unknown := dbgen.Candidate{ID: uuid.New(), ClearanceLevel: "unknown", ClearancePoly: "none", ClearanceStatus: "unknown"}
	u := clearanceCell(unknown, ClearanceFactsFrom(unknown, nil), asOf)
	if u.SciKnown || u.Level != "Unknown" {
		t.Fatalf("unknown clearance must be Unknown and not SciKnown, got %+v", u)
	}
}

func TestBuildCandidateIntelNoRequirements(t *testing.T) {
	asOf := time.Date(2026, 6, 24, 0, 0, 0, 0, time.UTC)
	c := dbgen.Candidate{ID: uuid.New(), FullName: "No Reqs Org", ClearanceLevel: "unknown", ClearancePoly: "none", ClearanceStatus: "unknown"}
	ec := engine.Candidate{ID: c.ID.String()}
	// Empty reqs and nil maps must not panic (regression for the index out of range crash).
	v, _ := buildCandidateIntel(context.Background(), c, ec, asOf, nil, nil, nil, nil, nil)
	if v.MissionReadiness.Status != "No open requirements" || v.BestFit.Name != "" || v.WinImpact.Level != "LOW" {
		t.Fatalf("a requirement free org must render a clean view, got %+v", v)
	}
}

func TestWinImpactCellTiers(t *testing.T) {
	if got := winImpactCell(3, 6, 12, "Data Scientist"); got.Level != "HIGH" || !strings.Contains(got.Basis, "6 of 12") {
		t.Fatalf("tier 3 must be HIGH citing the open count, got %+v", got)
	}
	if got := winImpactCell(2, 0, 5, "ISSO"); got.Level != "MEDIUM" {
		t.Fatalf("tier 2 must be MEDIUM, got %+v", got)
	}
	if got := winImpactCell(1, 0, 5, "Cyber Engineer"); got.Level != "LOW" {
		t.Fatalf("tier 1 (redundant depth) must be LOW, got %+v", got)
	}
	if got := winImpactCell(0, 0, 0, ""); got.Level != "LOW" {
		t.Fatalf("tier 0 must be LOW, got %+v", got)
	}
}