package main

import (
	"encoding/json"
	"io"
	"net/http"
	"net/http/httptest"
	"strings"
	"sync/atomic"
	"testing"
)

// TestExtractRoleFromNeed locks the four query-shape patterns documented
// in real_003_findings.md so a future change to the regex can't silently
// drop coverage of any production-shape style. Real_001 used `need`-only;
// real_003 confirmed `shorthand` cross-role bleed; the extended
// extractor in real_003b covers `client_first` + `looking` and leaves
// `shorthand` as a known limitation (no separator between role and city).
func TestExtractRoleFromNeed(t *testing.T) {
	cases := []struct {
		name  string
		query string
		want  string
	}{
		{
			"need style — original real_001 form",
			"Need 1 Forklift Operator in Detroit MI starting at 15:00 for Beacon Freight",
			"Forklift Operator",
		},
		{
			"need with deadline trailer",
			"Need 4 Pickers in Detroit MI starting at 13:30 for Beacon Freight, deadline 2026-05-28",
			"Pickers",
		},
		{
			"client_first style — added in real_003b",
			"Beacon Freight needs 1 Forklift Operator in Detroit MI at 15:00",
			"Forklift Operator",
		},
		{
			"client_first with multi-word client",
			"Parallel Machining needs 5 Warehouse Associates in Kansas City MO at 09:00",
			"Warehouse Associates",
		},
		{
			"looking style — added in real_003b",
			"Looking for 1 Forklift Operator at Beacon Freight in Detroit MI for 15:00 shift",
			"Forklift Operator",
		},
		{
			"looking with multi-word role + 4-digit count",
			"Looking for 1234 Senior Production Supervisors at Heritage Foods in Flint MI for 08:30 shift",
			"Senior Production Supervisors",
		},
		{
			"shorthand — known limitation, returns empty",
			"1 Forklift Operator Detroit MI 15:00 Beacon Freight",
			"",
		},
		{
			"shorthand multi-word city — also empty",
			"5 Warehouse Associates Kansas City MO 09:00 Parallel Machining",
			"",
		},
		{
			"lift-suite multi-constraint — no clean role, returns empty",
			"Forklift operator with OSHA-30, warehouse experience, day shift availability",
			"",
		},
		{
			"OOD honesty signal — lift-suite, returns empty",
			"Dental hygienist with three years experience, Indianapolis area",
			"",
		},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			got := extractRoleFromNeed(c.query)
			if got != c.want {
				t.Errorf("extractRoleFromNeed(%q) = %q, want %q", c.query, got, c.want)
			}
		})
	}
}

// fakeOllama returns a minimal Ollama-shape /api/chat handler that
// echoes a fixed role string. Counts hits so caching tests can assert
// on call count.
func fakeOllama(role string) (*httptest.Server, *int64) {
	var hits int64
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path != "/api/chat" {
			http.NotFound(w, r)
			return
		}
		atomic.AddInt64(&hits, 1)
		_, _ = io.ReadAll(r.Body)
		// Ollama wraps the model's response under message.content as
		// a JSON-string. The model's output is itself the
		// {"role":"..."} JSON our extractor parses.
		inner, _ := json.Marshal(map[string]string{"role": role})
		out, _ := json.Marshal(map[string]any{
			"message": map[string]string{"content": string(inner)},
		})
		w.Header().Set("Content-Type", "application/json")
		_, _ = w.Write(out)
	}))
	return srv, &hits
}

// TestRoleExtractor_RegexFirst locks the priority order: when the
// regex matches, the LLM must NOT be called even if configured. Same
// behavior the real_003b shipping config relies on (don't pay LLM
// cost on need/client_first/looking queries).
func TestRoleExtractor_RegexFirst(t *testing.T) {
	srv, hits := fakeOllama("LLM-WONT-BE-CALLED")
	defer srv.Close()
	rx := &roleExtractor{
		hc:        srv.Client(),
		ollamaURL: srv.URL,
		model:     "test-model", // LLM is configured...
	}
	got := rx.extract("Need 5 Forklift Operators in Detroit MI starting at 09:00 for ACME")
	if got != "Forklift Operators" {
		t.Errorf("regex should win on Need-form query, got %q", got)
	}
	if *hits != 0 {
		t.Errorf("LLM should not be called when regex matched, got %d hits", *hits)
	}
}

// TestRoleExtractor_LLMFallback locks the shorthand-coverage path:
// when regex returns empty AND LLM is configured, the LLM is called
// and its result is used. Closes the real_003 shorthand bleed at the
// extraction layer.
func TestRoleExtractor_LLMFallback(t *testing.T) {
	srv, hits := fakeOllama("CNC Operator")
	defer srv.Close()
	rx := &roleExtractor{
		hc:        srv.Client(),
		ollamaURL: srv.URL,
		model:     "test-model",
	}
	got := rx.extract("1 CNC Operator Detroit MI 17:30 Beacon Freight")
	if got != "CNC Operator" {
		t.Errorf("LLM fallback should fire on shorthand, got %q", got)
	}
	if *hits != 1 {
		t.Errorf("expected exactly 1 LLM hit, got %d", *hits)
	}
}

// TestRoleExtractor_LLMOffLeavesEmpty locks the opt-in default: with
// LLM model unset, shorthand queries return empty (preserves
// real_003b shipping config — no LLM cost paid by default).
func TestRoleExtractor_LLMOffLeavesEmpty(t *testing.T) {
	rx := &roleExtractor{} // model = "" disables LLM
	got := rx.extract("1 CNC Operator Detroit MI 17:30 Beacon Freight")
	if got != "" {
		t.Errorf("with LLM off, shorthand should return empty, got %q", got)
	}
}

// TestRoleExtractor_Cache locks the per-process cache: re-extracting
// the same query must NOT call the LLM twice. Paraphrase passes hit
// the same query under cold + warm + paraphrase + rejudge — without
// the cache that's 4× LLM cost per query.
func TestRoleExtractor_Cache(t *testing.T) {
	srv, hits := fakeOllama("Pickers")
	defer srv.Close()
	rx := &roleExtractor{
		hc:        srv.Client(),
		ollamaURL: srv.URL,
		model:     "test-model",
	}
	q := "4 Pickers Detroit MI 13:30 Beacon Freight"
	for i := 0; i < 3; i++ {
		got := rx.extract(q)
		if got != "Pickers" {
			t.Errorf("call %d: got %q, want Pickers", i, got)
		}
	}
	if *hits != 1 {
		t.Errorf("expected 1 LLM hit (rest cached), got %d", *hits)
	}
}

// TestRoleExtractor_NilSafe locks the nil-receiver behavior so call
// sites in matrixSearch + playbookRecord don't need a guard. nil
// extractor degrades to regex-only.
func TestRoleExtractor_NilSafe(t *testing.T) {
	var rx *roleExtractor
	got := rx.extract("Need 1 Loader in Indianapolis IN starting at 12:00 for Midway")
	if got != "Loader" {
		t.Errorf("nil receiver should still run regex, got %q", got)
	}
	got = rx.extract("1 CNC Operator Detroit MI 17:30 Beacon")
	if got != "" {
		t.Errorf("nil receiver should return empty when regex misses (no LLM), got %q", got)
	}
}

// TestExtractRoleViaLLM_HTTPError locks the failure path: HTTP non-2xx
// surfaces as an error so the caller can fall back to empty cleanly.
func TestExtractRoleViaLLM_HTTPError(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		http.Error(w, "internal", http.StatusInternalServerError)
	}))
	defer srv.Close()
	_, err := extractRoleViaLLM(srv.Client(), srv.URL, "test-model", "anything")
	if err == nil || !strings.Contains(err.Error(), "HTTP 500") {
		t.Errorf("expected HTTP 500 error, got %v", err)
	}
}

// TestRoleExtractor_ClosesCrossRoleShorthandBleed is the synthetic
// witness for the real_003 finding: when both record AND query are
// shorthand-style (no anchor between role and city), the regex
// returns "" for both. With LLM off, both sides go empty → gate
// disabled → cross-role bleed possible. With LLM on, both sides
// extract a non-empty role → role-mismatch is caught at the matrix
// gate.
//
// This test isolates the EXTRACTION layer (does the harness produce
// the right role token?). The matrix gate's behavior on those tokens
// is locked separately in internal/matrix/playbook_test.go's
// TestInjectPlaybookMisses_RoleGateRejectsCrossRole.
func TestRoleExtractor_ClosesCrossRoleShorthandBleed(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		body, _ := io.ReadAll(r.Body)
		// Determine which role to return based on the user message.
		role := ""
		if strings.Contains(string(body), "CNC") {
			role = "CNC Operator"
		} else if strings.Contains(string(body), "Forklift") {
			role = "Forklift Operator"
		}
		inner, _ := json.Marshal(map[string]string{"role": role})
		out, _ := json.Marshal(map[string]any{
			"message": map[string]string{"content": string(inner)},
		})
		_, _ = w.Write(out)
	}))
	defer srv.Close()

	rx := &roleExtractor{
		hc:        srv.Client(),
		ollamaURL: srv.URL,
		model:     "test-model",
	}

	// Both queries are shorthand — regex would return "" for both.
	// LLM extracts a real role for each, and they differ.
	cnc := rx.extract("1 CNC Operator Detroit MI 17:30 Beacon Freight")
	fork := rx.extract("1 Forklift Operator Detroit MI 15:00 Beacon Freight")

	if cnc != "CNC Operator" {
		t.Errorf("CNC shorthand should extract via LLM, got %q", cnc)
	}
	if fork != "Forklift Operator" {
		t.Errorf("Forklift shorthand should extract via LLM, got %q", fork)
	}
	if cnc == fork {
		t.Errorf("cross-role shorthand should produce DIFFERENT role tokens (cnc=%q fork=%q)", cnc, fork)
	}
}

// TestExtractRoleViaLLM_BadJSON locks the model-output validation: if
// the LLM returns non-JSON content, the error is surfaced (don't
// silently treat it as empty role).
func TestExtractRoleViaLLM_BadJSON(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		out, _ := json.Marshal(map[string]any{
			"message": map[string]string{"content": "this is not json"},
		})
		_, _ = w.Write(out)
	}))
	defer srv.Close()
	_, err := extractRoleViaLLM(srv.Client(), srv.URL, "test-model", "anything")
	if err == nil || !strings.Contains(err.Error(), "decode role") {
		t.Errorf("expected decode error, got %v", err)
	}
}