package updater

import (
	"bytes"
	"context"
	"io"
	"net/http"
	"net/url"
	"testing"

	"github.com/Snider/Borg/pkg/mocks"
)

func TestGithub_GetPublicRepos_Good(t *testing.T) {
	mockClient := mocks.NewMockClient(map[string]*http.Response{
		"https://api.github.com/users/testuser/repos": {
			StatusCode: http.StatusOK,
			Header:     http.Header{"Content-Type": []string{"application/json"}},
			Body:       io.NopCloser(bytes.NewBufferString(`[{"clone_url": "https://github.com/testuser/repo1.git"}]`)),
		},
		"https://api.github.com/orgs/testorg/repos": {
			StatusCode: http.StatusOK,
			Header:     http.Header{"Content-Type": []string{"application/json"}, "Link": []string{`<https://api.github.com/organizations/123/repos?page=2>; rel="next"`}},
			Body:       io.NopCloser(bytes.NewBufferString(`[{"clone_url": "https://github.com/testorg/repo1.git"}]`)),
		},
		"https://api.github.com/organizations/123/repos?page=2": {
			StatusCode: http.StatusOK,
			Header:     http.Header{"Content-Type": []string{"application/json"}},
			Body:       io.NopCloser(bytes.NewBufferString(`[{"clone_url": "https://github.com/testorg/repo2.git"}]`)),
		},
	})

	client := &githubClient{}
	originalNewAuthenticatedClient := NewAuthenticatedClient
	NewAuthenticatedClient = func(ctx context.Context) *http.Client {
		return mockClient
	}
	defer func() { NewAuthenticatedClient = originalNewAuthenticatedClient }()

	// Test user repos
	repos, err := client.getPublicReposWithAPIURL(context.Background(), "https://api.github.com", "testuser")
	if err != nil {
		t.Fatalf("getPublicReposWithAPIURL for user failed: %v", err)
	}
	if len(repos) != 1 || repos[0] != "https://github.com/testuser/repo1.git" {
		t.Errorf("unexpected user repos: %v", repos)
	}

	// Test org repos with pagination
	repos, err = client.getPublicReposWithAPIURL(context.Background(), "https://api.github.com", "testorg")
	if err != nil {
		t.Fatalf("getPublicReposWithAPIURL for org failed: %v", err)
	}
	if len(repos) != 2 || repos[0] != "https://github.com/testorg/repo1.git" || repos[1] != "https://github.com/testorg/repo2.git" {
		t.Errorf("unexpected org repos: %v", repos)
	}
}

func TestGithub_GetPublicRepos_Bad(t *testing.T) {
	u, _ := url.Parse("https://api.github.com/users/testuser/repos")
	mockClient := mocks.NewMockClient(map[string]*http.Response{
		"https://api.github.com/users/testuser/repos": {
			StatusCode: http.StatusNotFound,
			Status:     "404 Not Found",
			Header:     http.Header{"Content-Type": []string{"application/json"}},
			Body:       io.NopCloser(bytes.NewBufferString("")),
			Request:    &http.Request{Method: "GET", URL: u},
		},
		"https://api.github.com/orgs/testuser/repos": {
			StatusCode: http.StatusNotFound,
			Status:     "404 Not Found",
			Header:     http.Header{"Content-Type": []string{"application/json"}},
			Body:       io.NopCloser(bytes.NewBufferString("")),
			Request:    &http.Request{Method: "GET", URL: u},
		},
	})
	expectedErr := "github.getPublicReposWithAPIURL: failed to fetch repos: 404 Not Found"

	client := &githubClient{}
	originalNewAuthenticatedClient := NewAuthenticatedClient
	NewAuthenticatedClient = func(ctx context.Context) *http.Client {
		return mockClient
	}
	defer func() { NewAuthenticatedClient = originalNewAuthenticatedClient }()

	_, err := client.getPublicReposWithAPIURL(context.Background(), "https://api.github.com", "testuser")
	if err == nil || err.Error() != expectedErr {
		t.Fatalf("expected %q, got %q", expectedErr, err)
	}
}

func TestGithub_GetPublicRepos_Ugly(t *testing.T) {
	// Context already cancelled — loop should terminate immediately
	ctx, cancel := context.WithCancel(context.Background())
	cancel()

	mockClient := mocks.NewMockClient(map[string]*http.Response{})
	client := &githubClient{}
	originalNewAuthenticatedClient := NewAuthenticatedClient
	NewAuthenticatedClient = func(ctx context.Context) *http.Client { return mockClient }
	defer func() { NewAuthenticatedClient = originalNewAuthenticatedClient }()

	_, err := client.getPublicReposWithAPIURL(ctx, "https://api.github.com", "testuser")
	if err == nil {
		t.Error("expected error from cancelled context, got nil")
	}
}

func TestGithub_FindNextURL_Good(t *testing.T) {
	client := &githubClient{}
	linkHeader := `<https://api.github.com/organizations/123/repos?page=2>; rel="next", <https://api.github.com/organizations/123/repos?page=1>; rel="prev"`
	nextURL := client.findNextURL(linkHeader)
	if nextURL != "https://api.github.com/organizations/123/repos?page=2" {
		t.Errorf("unexpected next URL: %s", nextURL)
	}
}

func TestGithub_FindNextURL_Bad(t *testing.T) {
	client := &githubClient{}
	linkHeader := `<https://api.github.com/organizations/123/repos?page=1>; rel="prev"`
	nextURL := client.findNextURL(linkHeader)
	if nextURL != "" {
		t.Errorf("expected empty string for no next link, got %q", nextURL)
	}
}

func TestGithub_FindNextURL_Ugly(t *testing.T) {
	client := &githubClient{}
	// Empty header
	if got := client.findNextURL(""); got != "" {
		t.Errorf("expected empty string for empty header, got %q", got)
	}
	// Malformed header — no rel attribute
	if got := client.findNextURL(`<https://example.com/page=2>`); got != "" {
		t.Errorf("expected empty string for malformed header, got %q", got)
	}
}

func TestGithub_NewAuthenticatedClient_Good(t *testing.T) {
	// With token set — should return an authenticated (non-default) client
	t.Setenv("GITHUB_TOKEN", "test-token")
	client := NewAuthenticatedClient(context.Background())
	if client == http.DefaultClient {
		t.Error("expected authenticated client, got http.DefaultClient")
	}
}

func TestGithub_NewAuthenticatedClient_Bad(t *testing.T) {
	// Without token — should return a plain (unauthenticated) HTTP client, not http.DefaultClient
	t.Setenv("GITHUB_TOKEN", "")
	client := NewAuthenticatedClient(context.Background())
	if client == nil {
		t.Error("expected non-nil client when no token set")
	}
}

func TestGithub_NewAuthenticatedClient_Ugly(t *testing.T) {
	// Cancelled context still returns a client (client creation does not fail on cancelled context)
	ctx, cancel := context.WithCancel(context.Background())
	cancel()
	client := NewAuthenticatedClient(ctx)
	if client == nil {
		t.Error("expected non-nil client even with cancelled context")
	}
}