// Copyright (c) 2026 Probo Inc <hello@probo.com>.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

package drivers

import (
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"strings"

	"go.probo.inc/probo/pkg/coredata"
)

// BrexDriver fetches users from Brex via OAuth2-authenticated REST API
// requests.
type BrexDriver struct {
	httpClient *http.Client
}

var _ Driver = (*BrexDriver)(nil)

type brexUsersResponse struct {
	Items []struct {
		ID        string `json:"id"`
		FirstName string `json:"first_name"`
		LastName  string `json:"last_name"`
		Email     string `json:"email"`
		Status    string `json:"status"`
		Role      string `json:"role"`
	} `json:"items"`
	NextCursor string `json:"next_cursor"`
}

const brexUsersEndpoint = "https://platform.brexapis.com/v2/users"

func NewBrexDriver(httpClient *http.Client) *BrexDriver {
	return &BrexDriver{
		httpClient: httpClient,
	}
}

func (d *BrexDriver) ListAccounts(ctx context.Context) ([]AccountRecord, error) {
	var (
		records []AccountRecord
		cursor  *string
	)

	for range maxPaginationPages {
		resp, err := d.queryUsers(ctx, cursor)
		if err != nil {
			return nil, err
		}

		for _, u := range resp.Items {
			role := strings.TrimSpace(u.Role)

			roles := []string{}
			if role != "" {
				roles = []string{role}
			}

			record := AccountRecord{
				Email:       u.Email,
				FullName:    u.FirstName + " " + u.LastName,
				Roles:       roles,
				Active:      new(u.Status == "ACTIVE"),
				IsAdmin:     false,
				ExternalID:  u.ID,
				MFAStatus:   coredata.MFAStatusUnknown,
				AuthMethod:  coredata.AccessReviewEntryAuthMethodUnknown,
				AccountType: coredata.AccessReviewEntryAccountTypeUser,
			}

			if record.Email != "" {
				records = append(records, record)
			}
		}

		if resp.NextCursor == "" {
			return records, nil
		}

		nextCursor := resp.NextCursor
		cursor = &nextCursor
	}

	return nil, fmt.Errorf("cannot list all brex accounts: %w", ErrPaginationLimitReached)
}

func (d *BrexDriver) queryUsers(ctx context.Context, cursor *string) (*brexUsersResponse, error) {
	req, err := http.NewRequestWithContext(ctx, http.MethodGet, brexUsersEndpoint, nil)
	if err != nil {
		return nil, fmt.Errorf("cannot create brex users request: %w", err)
	}

	req.Header.Set("Accept", "application/json")
	req.Header.Set("Content-Type", "application/json")

	if cursor != nil {
		q := req.URL.Query()
		q.Set("cursor", *cursor)
		req.URL.RawQuery = q.Encode()
	}

	httpResp, err := d.httpClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("cannot execute brex users request: %w", err)
	}

	defer func() {
		_ = httpResp.Body.Close()
	}()

	if httpResp.StatusCode < 200 || httpResp.StatusCode >= 300 {
		return nil, fmt.Errorf("cannot fetch brex users: unexpected status %d", httpResp.StatusCode)
	}

	var resp brexUsersResponse
	if err := json.NewDecoder(httpResp.Body).Decode(&resp); err != nil {
		return nil, fmt.Errorf("cannot decode brex users response: %w", err)
	}

	return &resp, nil
}