package web

import (
	"context"
	"net/http"
	"time"

	"gitea.mynodes.xyz/ilker/llmgw/internal/audit"
	"gitea.mynodes.xyz/ilker/llmgw/internal/store"
)

// SetAudit has every change made through these pages recorded.
func (p *AccountPages) SetAudit(s audit.Sink) { p.audit = s }

// auditNote is what a handler says about the change it made: whom it was
// about, and how it ended in words — pages answer 200 to a refusal too.
type auditNote struct{ subject, result, refused string }

type auditNoteKey struct{}

// noteAudit lets the handler of a change say whom it concerned and how it
// ended.
func noteAudit(r *http.Request, subject, result, refused string) {
	if n, ok := r.Context().Value(auditNoteKey{}).(*auditNote); ok {
		n.subject, n.result, n.refused = subject, result, refused
	}
}

type statusRecorder struct {
	http.ResponseWriter
	status int
}

func (w *statusRecorder) WriteHeader(code int) {
	if w.status == 0 {
		w.status = code
	}
	w.ResponseWriter.WriteHeader(code)
}

func (w *statusRecorder) Write(b []byte) (int, error) {
	if w.status == 0 {
		w.status = http.StatusOK
	}
	return w.ResponseWriter.Write(b)
}

// audited runs a change and records it: who, which page, the form with its
// secrets taken out, and how it ended.
func (p *AccountPages) audited(w http.ResponseWriter, r *http.Request, actor store.User,
	run func(w http.ResponseWriter, r *http.Request),
) {
	if p.audit == nil || r.Method == http.MethodGet || r.Method == http.MethodHead {
		run(w, r)
		return
	}
	note := &auditNote{}
	r = r.WithContext(context.WithValue(r.Context(), auditNoteKey{}, note))
	sw := &statusRecorder{ResponseWriter: w}
	run(sw, r)
	fields := audit.FormFields(r.PostForm)
	if note.result != "" {
		fields["result"] = note.result
	}
	if note.refused != "" {
		fields["refused"] = note.refused
	}
	audit.Write(r.Context(), p.audit, p.log, store.AuditEvent{
		At: time.Now(), Actor: actor.Email, Source: "web", Action: r.Method + " " + r.URL.Path,
		Target: note.subject, Detail: audit.Redact(fields), Status: sw.status,
	})
}

// selfAudited records a change a person makes to their own account: a key
// made or revoked, a password changed.
func (p *AccountPages) selfAudited(h http.HandlerFunc) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		_, user, ok := p.session(r)
		if !ok {
			h(w, r)
			return
		}
		p.audited(w, r, user, h)
	}
}