package config

import (
	"os"
	"strings"
)

type Config struct {
	Port            string   // GITEA_MCP_PORT, default 8080
	GiteaBaseURL    string   // GITEA_BASE_URL, e.g. https://gitea.d-ma.be
	DefaultToken    string   // GITEA_MCP_DEFAULT_TOKEN, service PAT; used by Gitea client for all upstream calls
	StaticToken     string   // GITEA_MCP_STATIC_TOKEN, optional static bearer for service-to-service auth
	AllowedOwners   []string // GITEA_MCP_ALLOWED_OWNERS, comma-separated, default "mathias"
	OriginAllowlist []string // GITEA_MCP_ORIGIN_ALLOWLIST, comma-separated
	DexIssuerURL    string   // DEX_ISSUER_URL, e.g. https://auth.d-ma.be; empty disables JWT auth
	MCPAudience     string   // MCP_AUDIENCE, JWT audience claim to validate, e.g. claude-ai
	MCPResourceURL  string   // MCP_RESOURCE_URL, this server's public URL for /.well-known metadata
}

func Load() (Config, error) {
	cfg := Config{
		Port:            envOr("GITEA_MCP_PORT", "8080"),
		GiteaBaseURL:    os.Getenv("GITEA_BASE_URL"),
		DefaultToken:    os.Getenv("GITEA_MCP_DEFAULT_TOKEN"),
		StaticToken:     os.Getenv("GITEA_MCP_STATIC_TOKEN"),
		AllowedOwners:   splitCSV(envOr("GITEA_MCP_ALLOWED_OWNERS", "mathias")),
		OriginAllowlist: splitCSV(os.Getenv("GITEA_MCP_ORIGIN_ALLOWLIST")),
		DexIssuerURL:    os.Getenv("DEX_ISSUER_URL"),
		MCPAudience:     os.Getenv("MCP_AUDIENCE"),
		MCPResourceURL:  os.Getenv("MCP_RESOURCE_URL"),
	}
	return cfg, nil
}

func envOr(key, def string) string {
	if v := os.Getenv(key); v != "" {
		return v
	}
	return def
}

func splitCSV(s string) []string {
	if s == "" {
		return nil
	}
	parts := strings.Split(s, ",")
	out := make([]string, 0, len(parts))
	for _, p := range parts {
		if p = strings.TrimSpace(p); p != "" {
			out = append(out, p)
		}
	}
	return out
}