package webui

import (
	"encoding/json"
	"html/template"
	"net/http"
	"strconv"
	"strings"

	"mailgoserver/internal/db"
)

// webmailRulesList is the self-service mirror of rulesList (mailbox_rules.go) — same
// underlying CRUD (ListRulesForMailbox/CreateRuleMulti/UpdateRuleMulti/RemoveRule),
// just reached from the mailbox owner's own portal instead of an admin managing it on
// their behalf. ?edit=<id> loads an existing rule into the builder instead of a blank
// one, mirroring webmailSignaturesPage's ?edit= pattern.
func (a *App) webmailRulesList(w http.ResponseWriter, r *http.Request) {
	mbox := mailboxFromContext(r)
	rules, err := a.DB.ListRulesForMailbox(mbox.ID)
	if err != nil {
		setFlash(w, "error", "Error loading rules")
	}

	var editing *db.MailboxFilterRule
	editingConditions := []db.RuleCondition{}
	var editingMatchType string
	if idStr := r.URL.Query().Get("edit"); idStr != "" {
		editing, _ = a.DB.GetRuleByID(mbox.ID, int64(atoi(idStr)))
		if editing != nil {
			editingConditions, editingMatchType = editing.Conditions()
		}
	}
	// json.Marshal HTML-escapes <, >, & by default (Go's documented behavior
	// specifically for safe embedding in HTML/script contexts), so this is safe to
	// mark template.JS and emit raw — a condition value containing "</script>" can't
	// break out of the tag. Plain string would instead get html/template's own
	// JS-value auto-escaping applied on top, which quotes the whole blob as a single
	// JS string literal (mangling it — confirmed live, JSON.parse('"null"') is the
	// string "null", not an array, so seedData.forEach threw).
	editingConditionsJSON, _ := json.Marshal(editingConditions)

	a.render(w, r, "webmail_rules.html", M{
		"mailbox": mbox, "rules": rules, "flashes": popFlashes(w, r), "active_section": "rules",
		"editing": editing, "editing_match_type": editingMatchType,
		"editing_conditions_json": template.JS(editingConditionsJSON),
	})
}

// webmailSaveRule creates a new rule, or updates one when rule_id (a hidden form
// field, not a path segment — one form reused for add and edit, mirroring
// webmailSignatureSave) is set and non-zero.
func (a *App) webmailSaveRule(w http.ResponseWriter, r *http.Request) {
	mbox := mailboxFromContext(r)
	if err := r.ParseForm(); err != nil {
		setFlash(w, "error", "Invalid form submission")
		http.Redirect(w, r, MailboxPrefix+"/rules", http.StatusFound)
		return
	}
	ruleID := int64(atoi(r.FormValue("rule_id")))
	redirectTarget := MailboxPrefix + "/rules"
	if ruleID != 0 {
		redirectTarget += "?edit=" + strconv.FormatInt(ruleID, 10)
	}

	name := strings.TrimSpace(r.FormValue("name"))
	priority, _ := strconv.Atoi(r.FormValue("priority"))
	matchType := r.FormValue("match_type")
	action := r.FormValue("action")
	actionValue := strings.TrimSpace(r.FormValue("action_value"))

	conditions, ok := parseRuleConditions(r)
	if !ok || !validActions[action] {
		setFlash(w, "error", "Please fill in a valid condition and action")
		http.Redirect(w, r, redirectTarget, http.StatusFound)
		return
	}
	if action == "move_to_folder" && actionValue == "" {
		setFlash(w, "error", "Please name the folder to move matching mail into")
		http.Redirect(w, r, redirectTarget, http.StatusFound)
		return
	}
	if action == "forward" && !strings.Contains(actionValue, "@") {
		setFlash(w, "error", "Please enter a valid address to forward to")
		http.Redirect(w, r, redirectTarget, http.StatusFound)
		return
	}

	actionOptionsJSON := ""
	if action == "forward" {
		opts := db.RuleActionOptions{KeepCopy: r.FormValue("keep_copy") != ""}
		if b, err := json.Marshal(opts); err == nil {
			actionOptionsJSON = string(b)
		}
	}

	var err error
	if ruleID != 0 {
		err = a.DB.UpdateRuleMulti(mbox.ID, ruleID, priority, conditions, matchType, name, action, actionValue, actionOptionsJSON)
		// A checkbox only ever appears in the submitted form when checked — its
		// absence means "unchecked", not "field not present", so this can't be
		// folded into UpdateRuleMulti's own column list the way the others are.
		if err == nil {
			err = a.DB.SetRuleActive(ruleID, mbox.ID, r.FormValue("is_active") != "")
		}
	} else {
		_, err = a.DB.CreateRuleMulti(mbox.ID, priority, conditions, matchType, name, action, actionValue, actionOptionsJSON)
	}
	if err != nil {
		setFlash(w, "error", "Error saving rule")
		http.Redirect(w, r, redirectTarget, http.StatusFound)
		return
	}
	setFlash(w, "success", "Rule saved")
	http.Redirect(w, r, MailboxPrefix+"/rules", http.StatusFound)
}

func (a *App) webmailToggleRule(w http.ResponseWriter, r *http.Request) {
	mbox := mailboxFromContext(r)
	ruleID := int64(atoi(r.PathValue("rule_id")))
	rule, _ := a.DB.GetRuleByID(mbox.ID, ruleID)
	if rule == nil {
		setFlash(w, "error", "Rule not found")
		http.Redirect(w, r, MailboxPrefix+"/rules", http.StatusFound)
		return
	}
	if err := a.DB.SetRuleActive(ruleID, mbox.ID, !rule.IsActive); err != nil {
		setFlash(w, "error", "Error updating rule")
	} else if rule.IsActive {
		setFlash(w, "success", "Rule disabled")
	} else {
		setFlash(w, "success", "Rule enabled")
	}
	http.Redirect(w, r, MailboxPrefix+"/rules", http.StatusFound)
}

func (a *App) webmailRemoveRule(w http.ResponseWriter, r *http.Request) {
	mbox := mailboxFromContext(r)
	ruleID := int64(atoi(r.PathValue("rule_id")))
	if err := a.DB.RemoveRule(ruleID, mbox.ID); err != nil {
		setFlash(w, "error", "Error removing rule")
	} else {
		setFlash(w, "success", "Rule removed")
	}
	http.Redirect(w, r, MailboxPrefix+"/rules", http.StatusFound)
}