import "package:auto_route/auto_route.dart";
import "package:flutter/material.dart";
import "package:flutter_riverpod/flutter_riverpod.dart";

import "package:smol_mail/data/providers/providers.dart";
import "package:smol_mail/presentation/routes/app_router.gr.dart";
import "package:smol_mail/shared/utils/format.dart";
import "package:smol_mail/shared/utils/snackbar.dart";
import "package:smol_mail/smol/client.dart";
import "package:smol_mail/smol/store.dart";
import "package:smol_mail/smol/ui.dart";

/// The opened message: trust row (fingerprint and how the sender's key is
/// known), frontmatter fields, and the plain body — smol mail has no HTML.
class MessageView extends ConsumerWidget {
  final String folder;
  final MailRecord record;
  final OpenedRecord opened;
  final void Function(String senderKey)? onNameSender;

  const MessageView({
    super.key,
    required this.folder,
    required this.record,
    required this.opened,
    this.onNameSender,
  });

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    if (opened.error != null) {
      return Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text("<unreadable: ${opened.error}>",
              style: TextStyle(color: Theme.of(context).colorScheme.error)),
        ],
      );
    }

    final store = ref.watch(storeProvider);
    final client = ref.read(clientProvider);

    // Sent copies carry no signature from a third party; the trust row then
    // just says what they are.
    final isSent = folder == "sent";
    final isRequest = folder == "requests";
    final senderKey = opened.sender;
    final known = senderKey == null ? null : store.addressForKey(senderKey);
    final contact = known == null ? null : store.contact(known);
    final verifiedSender = contact?.verified ?? false;
    final replyTo = isSent ? null : client.replyAddress(opened);
    final accepted = known == null ? null : store.accepted(known);

    final subject =
        opened.subject.isEmpty ? "(no subject)" : opened.subject;

    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        Text(subject, style: Theme.of(context).textTheme.titleLarge),
        const SizedBox(height: 14),
        if (isSent) _badge(context, "your own sealed copy") else
          _badge(
            context,
            verifiedSender
                ? "verified sender key"
                : known != null
                    ? "key pinned on first use"
                    : "key bound to no address",
            alert: known == null,
          ),
        if (isRequest) ...[
          const SizedBox(height: 10),
          _badge(context, "arrived without an accept token (SPEC.md §5.8)", alert: true),
        ],
        if (!isSent && senderKey != null) ...[
          const SizedBox(height: 10),
          _keyBlock(context, "${fingerprint(senderKey)}\n$senderKey"),
        ],
        const SizedBox(height: 18),
        _field(context, isSent ? "To" : "From",
            isSent ? (record.recipient ?? "") : (known ?? "unknown sender")),
        _field(context, "Date", formatTime(opened.time)),
        for (final entry in opened.fields.entries)
          if (entry.key != "subject" && entry.key != "reply-to" && entry.key != "accept")
            _field(context, entry.key, entry.value),
        if (!isSent && replyTo != null)
          Row(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Expanded(child: _field(context, "Reply-To", replyTo.short)),
              TextButton(
                onPressed: () async {
                  try {
                    await client.saveReplyAddress(replyTo, senderKey!);
                    ref.read(revisionProvider.notifier).bump();
                    if (context.mounted) {
                      ScaffoldMessenger.of(context).showSnackBar(
                        const SnackBar(
                            content: Text("Address saved for this sender")),
                      );
                    }
                  } catch (err) {
                    if (context.mounted) {
                      showErrorSnackBar(context, err.toString());
                    }
                  }
                },
                child: const Text("Save"),
              ),
            ],
          ),
        if (!isSent && senderKey != null && onNameSender != null)
          Align(
            alignment: Alignment.centerLeft,
            child: TextButton(
              onPressed: () => onNameSender!(senderKey),
              child: const Text("Name this sender"),
            ),
          ),
        if (isRequest && known != null && !(accepted?.active ?? false))
          Align(
            alignment: Alignment.centerLeft,
            child: TextButton.icon(
              icon: const Icon(Icons.check_circle_outline, size: 18),
              label: const Text("Accept sender"),
              onPressed: () async {
                try {
                  await client.acceptContact(known);
                  ref.read(revisionProvider.notifier).bump();
                  if (context.mounted) {
                    ScaffoldMessenger.of(context).showSnackBar(
                      SnackBar(content: Text("$known accepted")),
                    );
                  }
                } catch (err) {
                  if (context.mounted) showErrorSnackBar(context, err.toString());
                }
              },
            ),
          ),
        const SizedBox(height: 10),
        const Divider(height: 1),
        const SizedBox(height: 20),
        SelectableText(
          opened.body,
          style: Theme.of(context).textTheme.bodyMedium,
        ),
        const SizedBox(height: 25),
        if (!isSent && senderKey != null)
          Align(
            alignment: Alignment.centerRight,
            child: OutlinedButton.icon(
              icon: const Icon(Icons.reply, size: 18),
              label: const Text("Reply"),
              onPressed: () => AutoRouter.of(context).push(
                ComposeRoute(
                  to: known ?? replyTo?.short ?? "",
                  subject: replySubject(opened.subject),
                ),
              ),
            ),
          ),
      ],
    );
  }

  Widget _badge(BuildContext context, String text, {bool alert = false}) {
    final scheme = Theme.of(context).colorScheme;
    final background = alert ? scheme.errorContainer : scheme.primaryContainer;
    final foreground = alert ? scheme.onErrorContainer : scheme.onPrimaryContainer;
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 4),
      decoration: BoxDecoration(
        color: background,
        borderRadius: BorderRadius.circular(10),
      ),
      child: Text(
        text,
        style: Theme.of(context)
            .textTheme
            .labelSmall!
            .copyWith(color: foreground, fontWeight: FontWeight.w500),
      ),
    );
  }

  /// Technical detail (fingerprint, full key) — quiet by design, so it never
  /// competes with the subject or body for attention.
  Widget _keyBlock(BuildContext context, String text) => Text(
        text,
        style: Theme.of(context).textTheme.bodySmall!.copyWith(
              fontSize: 12,
              height: 1.5,
              fontWeight: FontWeight.normal,
              color: Theme.of(context).colorScheme.onSurfaceVariant,
            ),
      );

  Widget _field(BuildContext context, String label, String value) => Padding(
        padding: const EdgeInsets.symmetric(vertical: 4),
        child: Row(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            SizedBox(
              width: 90,
              child: Text(label, style: Theme.of(context).textTheme.labelSmall),
            ),
            Expanded(
              child: Text(value, style: Theme.of(context).textTheme.bodySmall),
            ),
          ],
        ),
      );
}