package skill

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
)

// createTestSkill creates a temporary SKILL.md file for testing.
func createTestSkill(t *testing.T, dir, name, description string, triggers []string, body string) string {
	t.Helper()

	skillDir := filepath.Join(dir, name)
	if err := os.MkdirAll(skillDir, 0755); err != nil {
		t.Fatalf("failed to create skill dir: %v", err)
	}

	triggerStr := "[]"
	if len(triggers) > 0 {
		quoted := make([]string, len(triggers))
		for i, tr := range triggers {
			quoted[i] = `"` + tr + `"`
		}
		triggerStr = "[" + strings.Join(quoted, ", ") + "]"
	}

	manifest := "---\n"
	manifest += "name: " + name + "\n"
	manifest += "description: " + description + "\n"
	manifest += "triggers: " + triggerStr + "\n"
	manifest += "---\n\n"
	manifest += body

	manifestPath := filepath.Join(skillDir, "SKILL.md")
	if err := os.WriteFile(manifestPath, []byte(manifest), 0644); err != nil {
		t.Fatalf("failed to write SKILL.md: %v", err)
	}

	return manifestPath
}

func TestNewManager(t *testing.T) {
	m := NewManager("")
	if m == nil {
		t.Fatal("NewManager() returned nil")
	}
	if m.SkillsDir() == "" {
		t.Error("expected non-empty skills directory")
	}
}

func TestNewManagerWithCustomDir(t *testing.T) {
	tmpDir := t.TempDir()
	m := NewManager(tmpDir)

	if m.SkillsDir() != tmpDir {
		t.Errorf("expected skills dir %q, got %q", tmpDir, m.SkillsDir())
	}
}

func TestLoadAllNoDirectory(t *testing.T) {
	tmpDir := filepath.Join(t.TempDir(), "nonexistent")
	m := NewManager(tmpDir)

	count, err := m.LoadAll()
	if err != nil {
		t.Fatalf("LoadAll on nonexistent dir should not error: %v", err)
	}
	if count != 0 {
		t.Errorf("expected 0 skills, got %d", count)
	}
}

func TestLoadAllWithSkills(t *testing.T) {
	tmpDir := t.TempDir()

	createTestSkill(t, tmpDir, "skill-a", "Skill A", []string{"alpha", "a"}, "# Skill A\nContent")
	createTestSkill(t, tmpDir, "skill-b", "Skill B", []string{"beta", "b"}, "# Skill B\nContent")

	m := NewManager(tmpDir)
	count, err := m.LoadAll()
	if err != nil {
		t.Fatalf("LoadAll failed: %v", err)
	}
	if count != 2 {
		t.Errorf("expected 2 skills, got %d", count)
	}
}

func TestGetSkill(t *testing.T) {
	tmpDir := t.TempDir()
	createTestSkill(t, tmpDir, "test-skill", "Test Skill", []string{"test"}, "# Test")

	m := NewManager(tmpDir)
	m.LoadAll()

	skill, ok := m.GetSkill("test-skill")
	if !ok {
		t.Fatal("GetSkill returned false for existing skill")
	}
	if skill.Name != "test-skill" {
		t.Errorf("expected name 'test-skill', got %q", skill.Name)
	}
	if skill.Description != "Test Skill" {
		t.Errorf("expected description 'Test Skill', got %q", skill.Description)
	}
}

func TestGetSkillNotFound(t *testing.T) {
	tmpDir := t.TempDir()
	m := NewManager(tmpDir)
	m.LoadAll()

	_, ok := m.GetSkill("nonexistent")
	if ok {
		t.Error("expected false for nonexistent skill")
	}
}

func TestListSkills(t *testing.T) {
	tmpDir := t.TempDir()
	createTestSkill(t, tmpDir, "beta", "Beta", nil, "# Beta")
	createTestSkill(t, tmpDir, "alpha", "Alpha", nil, "# Alpha")

	m := NewManager(tmpDir)
	m.LoadAll()

	skills := m.ListSkills()
	if len(skills) != 2 {
		t.Errorf("expected 2 skills, got %d", len(skills))
	}

	// Should be sorted alphabetically
	if len(skills) >= 2 {
		if skills[0].Name != "alpha" {
			t.Errorf("expected first skill 'alpha', got %q", skills[0].Name)
		}
		if skills[1].Name != "beta" {
			t.Errorf("expected second skill 'beta', got %q", skills[1].Name)
		}
	}
}

func TestListSkillsEmpty(t *testing.T) {
	m := NewManager(t.TempDir())
	m.LoadAll()

	skills := m.ListSkills()
	if len(skills) != 0 {
		t.Errorf("expected empty list, got %d skills", len(skills))
	}
}

func TestFindSkill(t *testing.T) {
	tmpDir := t.TempDir()
	createTestSkill(t, tmpDir, "browser", "Browser automation", []string{"browser", "navigate", "screenshot"}, "# Browser")
	createTestSkill(t, tmpDir, "memory", "Project memory", []string{"memory", "remember"}, "# Memory")
	createTestSkill(t, tmpDir, "convert", "File converter", []string{"convert", "pdf"}, "# Convert")

	m := NewManager(tmpDir)
	m.LoadAll()

	// Find by trigger matching "browser"
	results := m.FindSkill("I need to use the browser to navigate")
	if len(results) == 0 {
		t.Fatal("expected at least 1 match for 'browser'")
	}

	found := false
	for _, s := range results {
		if s.Name == "browser" {
			found = true
			break
		}
	}
	if !found {
		t.Error("expected 'browser' skill in results")
	}
}

func TestFindSkillNoMatch(t *testing.T) {
	tmpDir := t.TempDir()
	createTestSkill(t, tmpDir, "browser", "Browser", []string{"browser"}, "# Browser")

	m := NewManager(tmpDir)
	m.LoadAll()

	results := m.FindSkill("completely unrelated query")
	if len(results) != 0 {
		t.Errorf("expected 0 matches, got %d", len(results))
	}
}

func TestFindSkillCaseInsensitive(t *testing.T) {
	tmpDir := t.TempDir()
	createTestSkill(t, tmpDir, "browser", "Browser", []string{"Browser"}, "# Browser")

	m := NewManager(tmpDir)
	m.LoadAll()

	results := m.FindSkill("browser")
	if len(results) != 1 {
		t.Errorf("expected 1 match for lowercase 'browser', got %d", len(results))
	}

	results = m.FindSkill("BROWSER")
	if len(results) != 1 {
		t.Errorf("expected 1 match for uppercase 'BROWSER', got %d", len(results))
	}
}

func TestFindSkillRelevanceOrder(t *testing.T) {
	tmpDir := t.TempDir()
	createTestSkill(t, tmpDir, "multi-match", "Multiple matches", []string{"alpha", "beta", "gamma"}, "# Multi")
	createTestSkill(t, tmpDir, "single-match", "Single match", []string{"alpha"}, "# Single")

	m := NewManager(tmpDir)
	m.LoadAll()

	// A query mentioning multiple triggers
	results := m.FindSkill("alpha beta")
	if len(results) != 2 {
		t.Errorf("expected 2 matches, got %d", len(results))
	}

	// The multi-match skill should come first (more trigger matches)
	if len(results) >= 2 {
		if results[0].Name != "multi-match" {
			t.Errorf("expected 'multi-match' first (more relevance), got %q", results[0].Name)
		}
	}
}

func TestReload(t *testing.T) {
	tmpDir := t.TempDir()
	createTestSkill(t, tmpDir, "initial", "Initial", []string{"init"}, "# Initial")

	m := NewManager(tmpDir)
	m.LoadAll()

	if len(m.ListSkills()) != 1 {
		t.Errorf("expected 1 skill after load, got %d", len(m.ListSkills()))
	}

	// Add another skill
	createTestSkill(t, tmpDir, "added", "Added later", []string{"new"}, "# New")

	count, err := m.Reload()
	if err != nil {
		t.Fatalf("Reload failed: %v", err)
	}
	if count != 2 {
		t.Errorf("expected 2 skills after reload, got %d", count)
	}
}

func TestSkillMatchTrigger(t *testing.T) {
	skill := &Skill{
		Name:     "test",
		Triggers: []string{"browser", "navigate"},
	}

	tests := []struct {
		query string
		want  bool
	}{
		{"I need to use the browser", true},
		{"navigate to a page", true},
		{"Browser automation", true},
		{"something unrelated", false},
	}

	for _, tt := range tests {
		got := skill.MatchTrigger(tt.query)
		if got != tt.want {
			t.Errorf("MatchTrigger(%q) = %v, want %v", tt.query, got, tt.want)
		}
	}
}

func TestSkillHasScripts(t *testing.T) {
	s1 := &Skill{Name: "no-scripts"}
	if s1.HasScripts() {
		t.Error("expected HasScripts() = false for empty scripts")
	}

	s2 := &Skill{Name: "has-scripts", Scripts: []string{"script.sh"}}
	if !s2.HasScripts() {
		t.Error("expected HasScripts() = true for non-empty scripts")
	}
}

func TestExpandHome(t *testing.T) {
	home, err := os.UserHomeDir()
	if err != nil {
		t.Fatalf("failed to get home dir: %v", err)
	}

	result := expandHome("~/test/path")
	if !strings.HasPrefix(result, home) {
		t.Errorf("expected path starting with %q, got %q", home, result)
	}

	// Non-tilde path should not change
	if expandHome("/absolute/path") != "/absolute/path" {
		t.Error("absolute path should not be modified")
	}
}