package workbench

import (
	"fmt"
	"net"
	"net/url"
	"regexp"
	"strings"

	"aigateway.local/core/internal/provider"
)

// ScanFinding 是一条供应链安全扫描发现。
type ScanFinding struct {
	Rule        string `json:"rule"`
	Severity    string `json:"severity"` // high / medium / low
	Description string `json:"description"`
	Match       string `json:"match,omitempty"`
}

// 静态扫描规则:对 skill/mcp 资源定义内容(描述、提示词、工具配置、URL 等)
// 做供应链安全检查,发现高危模式时在管理端展示。
var (
	secretPatterns = []struct {
		rule, severity, pattern, description string
		re                                  *regexp.Regexp
	}{
		{rule: "openai_key", severity: "high", pattern: `sk-[A-Za-z0-9_-]{16,}`, description: "疑似硬编码 OpenAI API Key"},
		{rule: "aws_key", severity: "high", pattern: `AKIA[0-9A-Z]{16}`, description: "疑似硬编码 AWS Access Key"},
		{rule: "github_token", severity: "high", pattern: `gh[pousr]_[A-Za-z0-9]{20,}`, description: "疑似硬编码 GitHub Token"},
		{rule: "stripe_key", severity: "high", pattern: `sk_live_[A-Za-z0-9]{20,}`, description: "疑似硬编码 Stripe 密钥"},
		{rule: "generic_secret", severity: "medium", pattern: `(?i)(password|passwd|secret|api[_-]?key|token)\s*[:=]\s*['"][^'"]{8,}['"]`, description: "疑似硬编码凭据赋值"},
		{rule: "private_key_block", severity: "high", pattern: `-----BEGIN (RSA |EC |OPENSSH )?PRIVATE KEY-----`, description: "包含私钥块"},
	}
	dangerCommandPatterns = []struct {
		pattern, description string
		re                   *regexp.Regexp
	}{
		{pattern: `(?i)(rm\s+-rf\s+/|:\(\)\s*\{[^}]*\}\s*;|mkfs\.|dd\s+if=.*of=/dev/)`, description: "包含危险系统命令"},
		{pattern: `(?i)curl\s+[^|;&]*\|\s*(ba)?sh|wget\s+[^|;&]*\|\s*(ba)?sh`, description: "管道执行远程脚本(curl|sh)"},
	}
	injectionPatterns = []struct {
		pattern, description string
		re                   *regexp.Regexp
	}{
		{pattern: `(?i)ignore (all |any )?(previous|prior) instructions`, description: "疑似提示词注入(忽略历史指令)"},
		{pattern: `(?i)(reveal|leak|exfiltrate|print)\s+(your|the)\s+(system\s+)?(prompt|instructions|secret)`, description: "疑似提示词注入(诱导泄露系统提示/密钥)"},
		{pattern: `(?i)(you are now|act as|pretend to be).{0,40}(no restrictions|unfiltered|jailbreak)`, description: "疑似越狱/解除限制指令"},
	}
)

func compileStaticPatterns() {
	for i := range secretPatterns {
		secretPatterns[i].re = regexp.MustCompile(secretPatterns[i].pattern)
	}
	for i := range dangerCommandPatterns {
		dangerCommandPatterns[i].re = regexp.MustCompile(dangerCommandPatterns[i].pattern)
	}
	for i := range injectionPatterns {
		injectionPatterns[i].re = regexp.MustCompile(injectionPatterns[i].pattern)
	}
}

func init() { compileStaticPatterns() }

// ScanResource 对资源定义内容执行静态安全扫描。
// content 为拼接的文本(名称、描述、提示词、工具 URL、配置等)。
func ScanResource(content string) []ScanFinding {
	findings := []ScanFinding{}
	scanText := func(patterns []struct {
		pattern, description string
		re                   *regexp.Regexp
	}, severity string) {
		for _, p := range patterns {
			if match := p.re.FindString(content); match != "" {
				findings = append(findings, ScanFinding{
					Rule: p.pattern, Severity: severity, Description: p.description,
					Match: truncateRune(match, 80),
				})
			}
		}
	}
	for _, p := range secretPatterns {
		if match := p.re.FindString(content); match != "" {
			findings = append(findings, ScanFinding{
				Rule: p.rule, Severity: p.severity, Description: p.description,
				Match: maskMatch(match),
			})
		}
	}
	scanText(dangerCommandPatterns, "high")
	scanText(injectionPatterns, "medium")

	// URL 与内网地址检测。
	urlPattern := regexp.MustCompile(`https?://[^\s"'<>]+`)
	for _, raw := range urlPattern.FindAllString(content, -1) {
		parsed, err := url.Parse(strings.Trim(raw, `.,;)]}'"`))
		if err != nil || parsed.Hostname() == "" {
			continue
		}
		if parsed.Scheme != "http" && parsed.Scheme != "https" {
			findings = append(findings, ScanFinding{Rule: "non_http_scheme", Severity: "high", Description: "包含非 http(s) 协议 URL(可能用于 SSRF/文件读取)", Match: truncateRune(raw, 80)})
			continue
		}
		if addresses, err := net.LookupIP(parsed.Hostname()); err == nil {
			for _, ip := range addresses {
				if !provider.IsPublicAddress(ip) {
					findings = append(findings, ScanFinding{Rule: "private_endpoint", Severity: "high", Description: "资源引用了内网/保留地址(" + ip.String() + "),可能被用于内网探测", Match: truncateRune(raw, 80)})
					break
				}
			}
		}
	}
	// base64 混淆检测(>=64 字符的 base64 串)。
	base64Pattern := regexp.MustCompile(`[A-Za-z0-9+/]{64,}={0,2}`)
	if match := base64Pattern.FindString(content); match != "" {
		findings = append(findings, ScanFinding{Rule: "obfuscated_blob", Severity: "low", Description: "包含疑似 base64 混淆数据", Match: truncateRune(match, 40) + "..."})
	}
	return findings
}

// HighestSeverity 返回发现中的最高严重级。
func HighestSeverity(findings []ScanFinding) string {
	order := map[string]int{"high": 0, "medium": 1, "low": 2}
	best := ""
	for _, f := range findings {
		if rank, ok := order[f.Severity]; ok {
			if best == "" || rank < order[best] {
				best = f.Severity
			}
		}
	}
	return best
}

func maskMatch(value string) string {
	if len(value) <= 8 {
		return "***"
	}
	return value[:4] + "…" + value[len(value)-4:]
}

func truncateRune(value string, limit int) string {
	runes := []rune(value)
	if len(runes) <= limit {
		return value
	}
	return string(runes[:limit]) + "…"
}

var _ = fmt.Sprintf