package handlers

import (
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"

	"github.com/gin-gonic/gin"
)

// ── ParseCapabilities ───────────────────────────────────────────────

func TestParseCapabilities_Full(t *testing.T) {
	manifest := map[string]any{
		"id": "test-pkg",
		"capabilities": map[string]any{
			"required": []any{"postgres", "pgvector"},
			"optional": []any{"s3"},
		},
	}
	caps, ok := ParseCapabilities(manifest)
	if !ok {
		t.Fatal("expected ok=true")
	}
	if len(caps.Required) != 2 || caps.Required[0] != "postgres" || caps.Required[1] != "pgvector" {
		t.Errorf("required = %v, want [postgres pgvector]", caps.Required)
	}
	if len(caps.Optional) != 1 || caps.Optional[0] != "s3" {
		t.Errorf("optional = %v, want [s3]", caps.Optional)
	}
}

func TestParseCapabilities_Missing(t *testing.T) {
	manifest := map[string]any{"id": "test-pkg"}
	_, ok := ParseCapabilities(manifest)
	if ok {
		t.Error("expected ok=false when no capabilities block")
	}
}

func TestParseCapabilities_EmptyArrays(t *testing.T) {
	manifest := map[string]any{
		"capabilities": map[string]any{
			"required": []any{},
			"optional": []any{},
		},
	}
	caps, ok := ParseCapabilities(manifest)
	if !ok {
		t.Fatal("expected ok=true")
	}
	if len(caps.Required) != 0 {
		t.Errorf("required should be empty, got %v", caps.Required)
	}
	if len(caps.Optional) != 0 {
		t.Errorf("optional should be empty, got %v", caps.Optional)
	}
}

func TestParseCapabilities_IgnoresEmpty(t *testing.T) {
	manifest := map[string]any{
		"capabilities": map[string]any{
			"required": []any{"pgvector", "", "postgres"},
		},
	}
	caps, _ := ParseCapabilities(manifest)
	if len(caps.Required) != 2 {
		t.Errorf("expected 2 entries (empty filtered), got %v", caps.Required)
	}
}

// ── CheckRequiredCapabilities ───────────────────────────────────────

func TestCheckRequired_AllMet(t *testing.T) {
	detected := map[string]bool{"postgres": true, "pgvector": true, "s3": true}
	missing := CheckRequiredCapabilities([]string{"postgres", "pgvector"}, detected)
	if len(missing) != 0 {
		t.Errorf("expected no missing, got %v", missing)
	}
}

func TestCheckRequired_SomeUnmet(t *testing.T) {
	detected := map[string]bool{"postgres": true, "pgvector": false, "s3": false}
	missing := CheckRequiredCapabilities([]string{"postgres", "pgvector", "s3"}, detected)
	if len(missing) != 2 {
		t.Errorf("expected 2 missing, got %v", missing)
	}
}

func TestCheckRequired_EmptyRequired(t *testing.T) {
	detected := map[string]bool{"postgres": true}
	missing := CheckRequiredCapabilities(nil, detected)
	if len(missing) != 0 {
		t.Errorf("expected no missing for nil required, got %v", missing)
	}
}

func TestCheckRequired_UnknownCap(t *testing.T) {
	detected := map[string]bool{"postgres": true}
	missing := CheckRequiredCapabilities([]string{"gpu"}, detected)
	if len(missing) != 1 || missing[0] != "gpu" {
		t.Errorf("expected [gpu], got %v", missing)
	}
}

// ── capabilityHelpText ──────────────────────────────────────────────

func TestCapabilityHelpText_KnownCaps(t *testing.T) {
	hints := capabilityHelpText([]string{"pgvector", "s3"})
	if len(hints) != 2 {
		t.Fatalf("expected 2 hints, got %d", len(hints))
	}
	if hints["pgvector"] == "" {
		t.Error("pgvector hint is empty")
	}
	if hints["s3"] == "" {
		t.Error("s3 hint is empty")
	}
}

func TestCapabilityHelpText_UnknownCap(t *testing.T) {
	hints := capabilityHelpText([]string{"gpu"})
	if hints["gpu"] == "" {
		t.Error("expected fallback hint for unknown cap")
	}
}

// ── DetectCapabilities (SQLite path — no real DB) ───────────────────

func TestDetectCapabilities_SQLite_NilStore(t *testing.T) {
	caps := DetectCapabilities(nil, false, nil, "")
	if caps["postgres"] {
		t.Error("postgres should be false on SQLite")
	}
	if caps["pgvector"] {
		t.Error("pgvector should be false on SQLite")
	}
	if caps["object_storage"] {
		t.Error("object_storage should be false with nil store")
	}
	if caps["s3"] {
		t.Error("s3 should be false with nil store")
	}
	if caps["workspace"] {
		t.Error("workspace should be false with empty root")
	}
}

func TestDetectCapabilities_WorkspaceWritable(t *testing.T) {
	tmpDir := t.TempDir()
	caps := DetectCapabilities(nil, false, nil, tmpDir)
	if !caps["workspace"] {
		t.Error("workspace should be true for writable temp dir")
	}
}

func TestDetectCapabilities_WorkspaceUnwritable(t *testing.T) {
	caps := DetectCapabilities(nil, false, nil, "/nonexistent/path/xyz")
	if caps["workspace"] {
		t.Error("workspace should be false for nonexistent path")
	}
}

// ── Admin endpoint ──────────────────────────────────────────────────

func TestGetCapabilities_HTTP(t *testing.T) {
	gin.SetMode(gin.TestMode)

	h := NewCapabilitiesHandler(func() map[string]bool {
		return map[string]bool{
			"postgres":       false,
			"pgvector":       false,
			"object_storage": true,
			"s3":             false,
			"workspace":      true,
		}
	})

	r := gin.New()
	r.GET("/api/v1/admin/capabilities", h.GetCapabilities)

	req := httptest.NewRequest(http.MethodGet, "/api/v1/admin/capabilities", nil)
	w := httptest.NewRecorder()
	r.ServeHTTP(w, req)

	if w.Code != 200 {
		t.Fatalf("status = %d, want 200", w.Code)
	}

	var result map[string]bool
	if err := json.Unmarshal(w.Body.Bytes(), &result); err != nil {
		t.Fatalf("unmarshal: %v", err)
	}

	if result["postgres"] {
		t.Error("postgres should be false")
	}
	if !result["object_storage"] {
		t.Error("object_storage should be true")
	}
	if !result["workspace"] {
		t.Error("workspace should be true")
	}
}