package main

import (
	_ "embed"
	"encoding/json"
	"fmt"
	"net/http"
	"strings"

	"github.com/kami/maven/internal/ipc"
)

//go:embed reminders.html
var remindersHTML string

var remindersTmpl = parsePage("reminders", remindersHTML, nil)

// reminderRow is one line on /reminders, with the payload unwrapped and both
// timestamps already in his clock.
//
// The page rendered `{{.Payload}}` and the UTC instant, so a reminder read
// `{"text":"выпить таблетки"}` and fired an hour off what he was told
// (Vikunja #469). Neither is a formatting nicety: the envelope is an internal
// shape he never chose, and a time on a page he reads is the time on his wall.
type reminderRow struct {
	Created string
	Fires   string
	Status  string
	Detail  string
	Text    string
}

// reminderText unwraps the {"text":...} payload the router writes.
//
// A copy of store.ReminderText rather than a call to it, because mavweb is one
// of the pure-Go daemons and internal/store carries the CGO sqlite driver. The
// ipc DTO is decoupled from the store on purpose, so the unwrap belongs to
// whoever renders it. Payload that is not that shape is shown as he said it.
func reminderText(payload string) string {
	var m map[string]any
	if err := json.Unmarshal([]byte(payload), &m); err == nil {
		if t, ok := m["text"]; ok {
			if s, isStr := t.(string); isStr && s != "" {
				return s
			}
		}
	}
	return strings.TrimSpace(payload)
}

func reminderRows(rs []ipc.Reminder) []reminderRow {
	out := make([]reminderRow, 0, len(rs))
	for _, r := range rs {
		status := r.Status
		detail := ""
		if !r.DeliveryBlockedTs.IsZero() {
			status = "blocked"
			detail = r.DeliveryBlockedError
		} else if r.DeliveryAttempts > 0 && !r.NextAttemptTs.IsZero() {
			detail = "retry " + r.NextAttemptTs.Local().Format("02 Jan 15:04")
		}
		out = append(out, reminderRow{
			Created: r.CreatedTs.Local().Format("02 Jan 15:04"),
			Fires:   r.FireTs.Local().Format("02 Jan 15:04"),
			Status:  status,
			Detail:  detail,
			Text:    reminderText(r.Payload),
		})
	}
	return out
}

func handleReminders(w http.ResponseWriter, r *http.Request, core ipc.CoreAPI) {
	if !requireCore(w, r, core, "reminders") {
		return
	}
	reminders, err := core.ListReminders(r.Context(), 50)
	if err != nil {
		writeProblem(w, r, http.StatusBadGateway, problemCoreReadFailed,
			"reminders unavailable", fmt.Errorf("list reminders: %w", err))
		return
	}
	renderPage(w, remindersTmpl, map[string]any{"Reminders": reminderRows(reminders)})
}