package repository

import (
	"context"
	"encoding/json"
	"io"
	"net/http"
	"net/http/httptest"
	"net/url"
	"strings"
	"testing"

	"github.com/Wei-Shaw/sub2api/internal/pkg/oauth"
	"github.com/stretchr/testify/require"
	"github.com/stretchr/testify/suite"
)

type ClaudeOAuthServiceSuite struct {
	suite.Suite
	srv    *httptest.Server
	client *claudeOAuthService
}

func (s *ClaudeOAuthServiceSuite) TearDownTest() {
	if s.srv != nil {
		s.srv.Close()
		s.srv = nil
	}
}

// requestCapture holds captured request data for assertions in the main goroutine.
type requestCapture struct {
	path        string
	method      string
	cookies     []*http.Cookie
	body        []byte
	formValues  url.Values
	bodyJSON    map[string]any
	contentType string
}

func (s *ClaudeOAuthServiceSuite) TestGetOrganizationUUID() {
	tests := []struct {
		name       string
		handler    http.HandlerFunc
		wantErr    bool
		errContain string
		wantUUID   string
		validate   func(captured requestCapture)
	}{
		{
			name: "success",
			handler: func(w http.ResponseWriter, r *http.Request) {
				w.Header().Set("Content-Type", "application/json")
				_, _ = w.Write([]byte(`[{"uuid":"org-1"}]`))
			},
			wantUUID: "org-1",
			validate: func(captured requestCapture) {
				require.Equal(s.T(), "/api/organizations", captured.path, "unexpected path")
				require.Len(s.T(), captured.cookies, 1, "expected 1 cookie")
				require.Equal(s.T(), "sessionKey", captured.cookies[0].Name)
				require.Equal(s.T(), "sess", captured.cookies[0].Value)
			},
		},
		{
			name: "non_200_returns_error",
			handler: func(w http.ResponseWriter, r *http.Request) {
				w.WriteHeader(http.StatusUnauthorized)
				_, _ = w.Write([]byte("unauthorized"))
			},
			wantErr:    true,
			errContain: "401",
		},
		{
			name: "invalid_json_returns_error",
			handler: func(w http.ResponseWriter, r *http.Request) {
				w.Header().Set("Content-Type", "application/json")
				_, _ = w.Write([]byte("not-json"))
			},
			wantErr: true,
		},
	}

	for _, tt := range tests {
		s.Run(tt.name, func() {
			var captured requestCapture

			s.srv = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				captured.path = r.URL.Path
				captured.cookies = r.Cookies()
				tt.handler(w, r)
			}))
			defer s.srv.Close()

			client, ok := NewClaudeOAuthClient().(*claudeOAuthService)
			require.True(s.T(), ok, "type assertion failed")
			s.client = client
			s.client.baseURL = s.srv.URL

			got, err := s.client.GetOrganizationUUID(context.Background(), "sess", "")

			if tt.wantErr {
				require.Error(s.T(), err)
				if tt.errContain != "" {
					require.ErrorContains(s.T(), err, tt.errContain)
				}
				return
			}

			require.NoError(s.T(), err)
			require.Equal(s.T(), tt.wantUUID, got)
			if tt.validate != nil {
				tt.validate(captured)
			}
		})
	}
}

func (s *ClaudeOAuthServiceSuite) TestGetAuthorizationCode() {
	tests := []struct {
		name     string
		handler  http.HandlerFunc
		wantErr  bool
		wantCode string
		validate func(captured requestCapture)
	}{
		{
			name: "parses_redirect_uri",
			handler: func(w http.ResponseWriter, r *http.Request) {
				w.Header().Set("Content-Type", "application/json")
				_ = json.NewEncoder(w).Encode(map[string]string{
					"redirect_uri": oauth.RedirectURI + "?code=AUTH&state=STATE",
				})
			},
			wantCode: "AUTH#STATE",
			validate: func(captured requestCapture) {
				require.True(s.T(), strings.HasPrefix(captured.path, "/v1/oauth/") && strings.HasSuffix(captured.path, "/authorize"), "unexpected path: %s", captured.path)
				require.Equal(s.T(), http.MethodPost, captured.method, "expected POST")
				require.Len(s.T(), captured.cookies, 1, "expected 1 cookie")
				require.Equal(s.T(), "sess", captured.cookies[0].Value)
				require.Equal(s.T(), "org-1", captured.bodyJSON["organization_uuid"])
				require.Equal(s.T(), oauth.ClientID, captured.bodyJSON["client_id"])
				require.Equal(s.T(), oauth.RedirectURI, captured.bodyJSON["redirect_uri"])
				require.Equal(s.T(), "st", captured.bodyJSON["state"])
			},
		},
		{
			name: "missing_code_returns_error",
			handler: func(w http.ResponseWriter, r *http.Request) {
				w.Header().Set("Content-Type", "application/json")
				_ = json.NewEncoder(w).Encode(map[string]string{
					"redirect_uri": oauth.RedirectURI + "?state=STATE", // no code
				})
			},
			wantErr: true,
		},
	}

	for _, tt := range tests {
		s.Run(tt.name, func() {
			var captured requestCapture

			s.srv = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				captured.path = r.URL.Path
				captured.method = r.Method
				captured.cookies = r.Cookies()
				captured.body, _ = io.ReadAll(r.Body)
				_ = json.Unmarshal(captured.body, &captured.bodyJSON)
				tt.handler(w, r)
			}))
			defer s.srv.Close()

			client, ok := NewClaudeOAuthClient().(*claudeOAuthService)
			require.True(s.T(), ok, "type assertion failed")
			s.client = client
			s.client.baseURL = s.srv.URL

			code, err := s.client.GetAuthorizationCode(context.Background(), "sess", "org-1", oauth.ScopeProfile, "cc", "st", "")

			if tt.wantErr {
				require.Error(s.T(), err)
				return
			}

			require.NoError(s.T(), err)
			require.Equal(s.T(), tt.wantCode, code)
			if tt.validate != nil {
				tt.validate(captured)
			}
		})
	}
}

func (s *ClaudeOAuthServiceSuite) TestExchangeCodeForToken() {
	tests := []struct {
		name     string
		handler  http.HandlerFunc
		code     string
		wantErr  bool
		wantResp *oauth.TokenResponse
		validate func(captured requestCapture)
	}{
		{
			name: "sends_state_when_embedded",
			handler: func(w http.ResponseWriter, r *http.Request) {
				w.Header().Set("Content-Type", "application/json")
				_ = json.NewEncoder(w).Encode(oauth.TokenResponse{
					AccessToken:  "at",
					TokenType:    "bearer",
					ExpiresIn:    3600,
					RefreshToken: "rt",
					Scope:        "s",
				})
			},
			code: "AUTH#STATE2",
			wantResp: &oauth.TokenResponse{
				AccessToken:  "at",
				RefreshToken: "rt",
			},
			validate: func(captured requestCapture) {
				require.Equal(s.T(), http.MethodPost, captured.method, "expected POST")
				require.True(s.T(), strings.HasPrefix(captured.contentType, "application/json"), "unexpected content-type")
				require.Equal(s.T(), "AUTH", captured.bodyJSON["code"])
				require.Equal(s.T(), "STATE2", captured.bodyJSON["state"])
				require.Equal(s.T(), oauth.ClientID, captured.bodyJSON["client_id"])
				require.Equal(s.T(), oauth.RedirectURI, captured.bodyJSON["redirect_uri"])
				require.Equal(s.T(), "ver", captured.bodyJSON["code_verifier"])
			},
		},
		{
			name: "non_200_returns_error",
			handler: func(w http.ResponseWriter, r *http.Request) {
				w.WriteHeader(http.StatusBadRequest)
				_, _ = w.Write([]byte("bad request"))
			},
			code:    "AUTH",
			wantErr: true,
		},
	}

	for _, tt := range tests {
		s.Run(tt.name, func() {
			var captured requestCapture

			s.srv = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				captured.method = r.Method
				captured.contentType = r.Header.Get("Content-Type")
				captured.body, _ = io.ReadAll(r.Body)
				_ = json.Unmarshal(captured.body, &captured.bodyJSON)
				tt.handler(w, r)
			}))
			defer s.srv.Close()

			client, ok := NewClaudeOAuthClient().(*claudeOAuthService)
			require.True(s.T(), ok, "type assertion failed")
			s.client = client
			s.client.tokenURL = s.srv.URL

			resp, err := s.client.ExchangeCodeForToken(context.Background(), tt.code, "ver", "", "")

			if tt.wantErr {
				require.Error(s.T(), err)
				return
			}

			require.NoError(s.T(), err)
			require.Equal(s.T(), tt.wantResp.AccessToken, resp.AccessToken)
			require.Equal(s.T(), tt.wantResp.RefreshToken, resp.RefreshToken)
			if tt.validate != nil {
				tt.validate(captured)
			}
		})
	}
}

func (s *ClaudeOAuthServiceSuite) TestRefreshToken() {
	tests := []struct {
		name     string
		handler  http.HandlerFunc
		wantErr  bool
		wantResp *oauth.TokenResponse
		validate func(captured requestCapture)
	}{
		{
			name: "sends_form",
			handler: func(w http.ResponseWriter, r *http.Request) {
				w.Header().Set("Content-Type", "application/json")
				_ = json.NewEncoder(w).Encode(oauth.TokenResponse{AccessToken: "at2", TokenType: "bearer", ExpiresIn: 3600})
			},
			wantResp: &oauth.TokenResponse{AccessToken: "at2"},
			validate: func(captured requestCapture) {
				require.Equal(s.T(), http.MethodPost, captured.method, "expected POST")
				require.Equal(s.T(), "refresh_token", captured.formValues.Get("grant_type"))
				require.Equal(s.T(), "rt", captured.formValues.Get("refresh_token"))
				require.Equal(s.T(), oauth.ClientID, captured.formValues.Get("client_id"))
			},
		},
		{
			name: "non_200_returns_error",
			handler: func(w http.ResponseWriter, r *http.Request) {
				w.WriteHeader(http.StatusUnauthorized)
				_, _ = w.Write([]byte("unauthorized"))
			},
			wantErr: true,
		},
	}

	for _, tt := range tests {
		s.Run(tt.name, func() {
			var captured requestCapture

			s.srv = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				captured.method = r.Method
				captured.body, _ = io.ReadAll(r.Body)
				captured.formValues, _ = url.ParseQuery(string(captured.body))
				tt.handler(w, r)
			}))
			defer s.srv.Close()

			client, ok := NewClaudeOAuthClient().(*claudeOAuthService)
			require.True(s.T(), ok, "type assertion failed")
			s.client = client
			s.client.tokenURL = s.srv.URL

			resp, err := s.client.RefreshToken(context.Background(), "rt", "")

			if tt.wantErr {
				require.Error(s.T(), err)
				return
			}

			require.NoError(s.T(), err)
			require.Equal(s.T(), tt.wantResp.AccessToken, resp.AccessToken)
			if tt.validate != nil {
				tt.validate(captured)
			}
		})
	}
}

func TestClaudeOAuthServiceSuite(t *testing.T) {
	suite.Run(t, new(ClaudeOAuthServiceSuite))
}
