package caddy

import (
	"encoding/json"
	"fmt"
	"net/http"
	"strings"
	"time"
)

type LogEntry struct {
	rawLogEntry
	Timestamp time.Time
	Duration  time.Duration
}

type logRequest struct {
	RemoteIP   string      `json:"remote_ip"`
	RemotePort string      `json:"remote_port"`
	ClientIP   string      `json:"client_ip"`
	Proto      string      `json:"proto"`
	Method     string      `json:"method"`
	Host       string      `json:"host"`
	URI        string      `json:"uri"`
	Headers    http.Header `json:"headers"`
}

type rawLogEntry struct {
	Level     string     `json:"level"`
	Timestamp float64    `json:"ts"`
	Logger    string     `json:"logger"`
	Message   string     `json:"msg"`
	Upstream  string     `json:"upstream"`
	Duration  float64    `json:"duration"`
	Request   logRequest `json:"request"`
}

func FromJSON(jsonData []byte) (logEntry LogEntry, err error) {
	rawLogEntry := rawLogEntry{}
	err = json.Unmarshal(jsonData, &rawLogEntry)
	if err != nil {
		return logEntry, fmt.Errorf("failed to JSON unmarshal caddy log entry: %w", err)
	}

	rawLogEntry.Request.Host = stripPort(rawLogEntry.Request.Host)

	seconds := int64(rawLogEntry.Timestamp)
	nanoSeconds := int64((rawLogEntry.Timestamp - float64(seconds)) * 1e9)

	logEntry.Timestamp = time.Unix(seconds, nanoSeconds)
	logEntry.Duration = time.Duration(float64(time.Second) * rawLogEntry.Duration)
	logEntry.rawLogEntry = rawLogEntry

	return logEntry, nil
}

func stripPort(host string) string {
	portIndex := strings.Index(host, ":")
	if portIndex >= 0 {
		return host[:portIndex]
	}

	return host
}