package checker

import (
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"net/url"
	"time"

	sdk "git.happydns.org/checker-sdk-go/checker"
)

const pulsediveEndpoint = "https://pulsedive.com/api/info.php"

func init() { Register(&pulsediveSource{endpoint: pulsediveEndpoint}) }

type pulsediveSource struct{ endpoint string }

func (*pulsediveSource) ID() string   { return "pulsedive" }
func (*pulsediveSource) Name() string { return "Pulsedive" }

func (*pulsediveSource) Options() SourceOptions {
	return SourceOptions{
		Admin: []sdk.CheckerOptionField{
			{
				Id:          "pulsedive_api_key",
				Type:        "string",
				Label:       "Pulsedive API key",
				Description: "Pulsedive API key (free account at pulsedive.com). Leave empty to skip Pulsedive lookups.",
				Secret:      true,
			},
		},
	}
}

type pulsediveDetails struct {
	Risk    string           `json:"risk"`
	Threats []pulsediveThreat `json:"threats"`
}

type pulsediveThreat struct {
	Name     string `json:"name"`
	Category string `json:"category"`
	Risk     string `json:"risk,omitempty"`
}

func (s *pulsediveSource) Query(ctx context.Context, domain, registered string, opts sdk.CheckerOptions) []SourceResult {
	apiKey := stringOpt(opts, "pulsedive_api_key")
	if apiKey == "" || registered == "" {
		return disabledResult(s.ID(), s.Name())
	}

	res := SourceResult{
		SourceID:  s.ID(),
		SourceName: s.Name(),
		Enabled:   true,
		Reference: "https://pulsedive.com/indicator/" + registered,
	}

	params := url.Values{
		"indicator": {registered},
		"key":       {apiKey},
	}
	reqURL := s.endpoint + "?" + params.Encode()

	reqCtx, cancel := context.WithTimeout(ctx, 15*time.Second)
	defer cancel()

	req, err := http.NewRequestWithContext(reqCtx, http.MethodGet, reqURL, nil)
	if err != nil {
		res.Error = redactSecret(err.Error(), apiKey)
		return []SourceResult{res}
	}
	req.Header.Set("User-Agent", "happydomain-checker-blacklist/1.0")

	body, status, err := httpDo(req, 1<<20)
	if err != nil {
		res.Error = redactSecret(err.Error(), apiKey)
		return []SourceResult{res}
	}
	if status != http.StatusOK {
		res.Error = fmt.Sprintf("HTTP %d: %s", status, truncate(string(body), 200))
		return []SourceResult{res}
	}

	// Check for "not found" before full parse — Pulsedive returns 200
	// with {"error": "Indicator not found."} for unknown indicators.
	var errEnvelope struct {
		Error string `json:"error"`
	}
	if json.Unmarshal(body, &errEnvelope) == nil && errEnvelope.Error != "" {
		return []SourceResult{res}
	}

	var parsed struct {
		Risk    string `json:"risk"`
		Threats []struct {
			Name     string `json:"name"`
			Category string `json:"category"`
			Risk     string `json:"risk"`
		} `json:"threats"`
	}
	if err := json.Unmarshal(body, &parsed); err != nil {
		res.Error = "decode: " + err.Error()
		return []SourceResult{res}
	}

	d := pulsediveDetails{Risk: parsed.Risk}
	seen := map[string]bool{}
	for _, t := range parsed.Threats {
		d.Threats = append(d.Threats, pulsediveThreat{
			Name:     t.Name,
			Category: t.Category,
			Risk:     t.Risk,
		})
		if !seen[t.Name] {
			seen[t.Name] = true
			res.Reasons = append(res.Reasons, t.Name)
		}
		res.Evidence = append(res.Evidence, Evidence{
			Label:  "Threat",
			Value:  t.Name,
			Status: t.Category,
		})
	}
	res.Details = mustJSON(d)
	return []SourceResult{res}
}

func (*pulsediveSource) Evaluate(r SourceResult) (bool, string) {
	if !r.Enabled || r.Error != "" || len(r.Evidence) == 0 {
		return false, ""
	}
	var d pulsediveDetails
	_ = json.Unmarshal(r.Details, &d)
	switch d.Risk {
	case "critical", "high":
		return true, SeverityCrit
	default:
		return true, SeverityWarn
	}
}

func (*pulsediveSource) Diagnose(res SourceResult) Diagnosis {
	var d pulsediveDetails
	_ = json.Unmarshal(res.Details, &d)
	previewN := min(len(d.Threats), 5)
	names := make([]string, 0, previewN)
	for _, t := range d.Threats[:previewN] {
		names = append(names, t.Name)
	}
	return Diagnosis{
		Severity: SeverityCrit,
		Title:    fmt.Sprintf("Pulsedive risk: %s — %d threat(s) associated", d.Risk, len(d.Threats)),
		Detail: fmt.Sprintf(
			"Pulsedive assigned a risk of %q to this domain. Associated threat(s): %s. Review the indicator page for feed context, related IPs, and historical activity, then follow up with the relevant threat's removal or remediation procedure.",
			d.Risk, joinNonEmpty(names, ", "),
		),
		Fix:      res.Reference,
		FixIsURL: res.Reference != "",
	}
}