package email

import (
	"bytes"
	"context"
	"encoding/json"
	"io"
	"net/http"
	"strconv"
	"time"

	"git.sendico.io/tech/sxchnge/notifications/model"
)

func (c *client) post(ctx context.Context, key string, payload any) Outcome {
	body, err := json.Marshal(payload)
	if err != nil {
		return Outcome{State: model.Failed, Code: "invalid_payload"}
	}
	req, err := http.NewRequestWithContext(ctx, http.MethodPost, c.endpoint, bytes.NewReader(body))
	if err != nil {
		return Outcome{State: model.Failed, Code: "invalid_provider_config"}
	}
	req.Header.Set("Authorization", "Bearer "+c.key)
	req.Header.Set("Content-Type", "application/json")
	if key != "" {
		req.Header.Set("Idempotency-Key", key)
	}
	resp, err := c.http.Do(req)
	if err != nil {
		return Outcome{State: model.Unknown, Code: "provider_outcome_unknown"}
	}
	defer resp.Body.Close()
	// Discard a bounded response without logging provider-controlled content.
	_, _ = io.Copy(io.Discard, io.LimitReader(resp.Body, 64<<10))
	switch {
	case resp.StatusCode >= 200 && resp.StatusCode < 300:
		return Outcome{State: model.Accepted}
	case resp.StatusCode == 429:
		delay := time.Minute
		if n, e := strconv.Atoi(resp.Header.Get("Retry-After")); e == nil && n > 0 && n <= 86400 {
			delay = time.Duration(n) * time.Second
		} else if date, e := http.ParseTime(resp.Header.Get("Retry-After")); e == nil && time.Until(date) > 0 {
			delay = time.Until(date)
		}
		return Outcome{State: model.RetryWait, Code: "provider_rate_limited", RetryAfter: delay}
	case resp.StatusCode >= 500 || resp.StatusCode == 408:
		return Outcome{State: model.Unknown, Code: "provider_outcome_unknown"}
	case resp.StatusCode == 401 || resp.StatusCode == 403:
		return Outcome{State: model.Failed, Code: "provider_authentication_failed"}
	default:
		return Outcome{State: model.Failed, Code: "provider_rejected"}
	}
}