package main

import (
	"bufio"
	"crypto/rand"
	"encoding/hex"
	"fmt"
	"net/http"
	"os"
	"strconv"
	"strings"
)

// readAPIKey returns the trimmed contents of $JEAN_HOME/.api_key, or "" if the
// file is absent/empty. This store is independent of config.env so the key
// survives preset switches (which rewrite config.env wholesale).
func readAPIKey() string {
	b, err := os.ReadFile(apiKeyPath())
	if err != nil {
		return ""
	}
	return strings.TrimSpace(string(b))
}

// authHeader sets the Authorization: Bearer header on req when an API key is
// configured, so jean's own internal calls (chat/web/bench/test) authenticate
// against a protected llama-server. No-op when no key is set.
func authHeader(req *http.Request) {
	if k := readAPIKey(); k != "" {
		req.Header.Set("Authorization", "Bearer "+k)
	}
}

// cmdSetAPIKey sets (or clears) the API key stored in $JEAN_HOME/.api_key. When
// exposed on the internet, llama-server requires "Authorization: Bearer <clé>"
// for every call.
//
//	jean set-api-key <clé>     définit la clé
//	jean set-api-key           génère une clé aléatoire
//	jean set-api-key ""        supprime la protection
func cmdSetAPIKey(args []string) error {
	var key string
	switch {
	case len(args) == 0:
		buf := make([]byte, 24)
		if _, err := rand.Read(buf); err != nil {
			return err
		}
		key = "sk-jean-" + hex.EncodeToString(buf)
		fmt.Printf("%s clé générée : %s\n", green("[ok]"), bold(key))
	case args[0] == "" || args[0] == "off" || args[0] == "none":
		key = ""
	default:
		key = strings.TrimSpace(args[0])
	}
	// Stocke dans le fichier dédié (survit aux switches de preset). On nettoie
	// aussi un éventuel API_KEY résiduel dans config.env pour éviter la confusion.
	_ = SetConfigKey("API_KEY", "")
	if key == "" {
		if err := os.Remove(apiKeyPath()); err != nil && !os.IsNotExist(err) {
			return err
		}
	} else if err := os.WriteFile(apiKeyPath(), []byte(key+"\n"), 0o600); err != nil {
		return err
	}
	if key == "" {
		fmt.Printf("%s API_KEY supprimée — serveur ouvert (pas d'authentification)\n", yellow("[info]"))
	} else {
		fmt.Printf("%s API_KEY enregistrée dans %s\n", green("[ok]"), apiKeyPath())
		fmt.Printf("       les clients doivent envoyer : %s\n", dim("Authorization: Bearer "+key))
	}
	fmt.Print(dim("[info] redémarrer le service pour appliquer ? [Y/n] "))
	sc := bufio.NewScanner(os.Stdin)
	if sc.Scan() && strings.HasPrefix(strings.ToLower(strings.TrimSpace(sc.Text())), "n") {
		fmt.Println(dim("[info] pense à lancer 'jean restart'"))
		return nil
	}
	return serviceAction("restart")
}

// ReadConfig parses config.env into a key/value map.
// Lines starting with '#' and blanks are ignored. Values may be quoted with ".
func ReadConfig() map[string]string {
	m := map[string]string{}
	b, err := os.ReadFile(confPath())
	if err != nil {
		return m
	}
	for _, line := range strings.Split(string(b), "\n") {
		s := strings.TrimSpace(line)
		if s == "" || strings.HasPrefix(s, "#") {
			continue
		}
		i := strings.IndexByte(s, '=')
		if i < 0 {
			continue
		}
		k := strings.TrimSpace(s[:i])
		v := strings.TrimSpace(s[i+1:])
		v = strings.Trim(v, "\"")
		m[k] = v
	}
	return m
}

// SetConfigKey sets key=value in config.env, updating the line in place if the
// key already exists (preserving comments/order) or appending it otherwise.
// An empty value removes the key. The file is created if missing.
func SetConfigKey(key, value string) error {
	b, _ := os.ReadFile(confPath())
	lines := []string{}
	if len(b) > 0 {
		lines = strings.Split(strings.TrimRight(string(b), "\n"), "\n")
	}
	newLine := key + "=" + value
	found := false
	out := []string{}
	for _, line := range lines {
		s := strings.TrimSpace(line)
		if s == "" || strings.HasPrefix(s, "#") {
			out = append(out, line)
			continue
		}
		i := strings.IndexByte(s, '=')
		if i >= 0 && strings.TrimSpace(s[:i]) == key {
			found = true
			if value != "" {
				out = append(out, newLine)
			}
			// empty value => drop the line
			continue
		}
		out = append(out, line)
	}
	if !found && value != "" {
		out = append(out, newLine)
	}
	content := strings.Join(out, "\n") + "\n"
	return os.WriteFile(confPath(), []byte(content), 0o644)
}

// LLMPort returns the configured server port (config.env PORT), default 8080.
func LLMPort() int {
	if p, ok := ReadConfig()["PORT"]; ok {
		if n, err := strconv.Atoi(p); err == nil && n > 0 {
			return n
		}
	}
	return 8080
}