/**
 * Contenido del detalle de una incidencia. Se reutiliza en móvil (pantalla
 * navegada) y en tablet (panel derecho del maestro-detalle).
 *
 * Todas las acciones pasan por src/sync/mutations.ts: escriben en local y
 * encolan la operación. Tras cada cambio refrescamos desde la BD.
 */
import React, { useCallback, useEffect, useState } from 'react';
import { ScrollView, StyleSheet, Text, TouchableOpacity, View } from 'react-native';
import {
  Issue,
  IssueComment,
  IssuePriority,
  IssueStatus,
  IssueTask,
} from '../../api/types';
import { hasPermission, useSession } from '../../auth/session';
import {
  getIssue,
  getIssueComments,
  getIssueTasks,
} from '../../db/repositories';
import {
  createIssueComment,
  createIssueTask,
  updateIssue,
  updateIssueTask,
} from '../../sync/mutations';
import {
  Badge,
  Card,
  ChipSelect,
  EmptyState,
  Field,
  ISSUE_PRIORITY_COLOR,
  ISSUE_STATUS_COLOR,
  PrimaryButton,
  SectionTitle,
} from '../../ui/components';
import { MediaStrip } from '../../ui/MediaStrip';

const STATUSES: readonly IssueStatus[] = ['open', 'in_review', 'resolved', 'closed'];
const PRIORITIES: readonly IssuePriority[] = ['low', 'medium', 'high', 'critical'];

export function IssueDetailContent({ issueId }: { issueId: number }) {
  const { user } = useSession();
  const canEdit = hasPermission(user, 'edit issues');

  const [issue, setIssue] = useState<Issue | null>(null);
  const [tasks, setTasks] = useState<IssueTask[]>([]);
  const [comments, setComments] = useState<IssueComment[]>([]);
  const [newTask, setNewTask] = useState('');
  const [newComment, setNewComment] = useState('');

  const refresh = useCallback(async () => {
    const [i, t, c] = await Promise.all([
      getIssue(issueId),
      getIssueTasks(issueId),
      getIssueComments(issueId),
    ]);
    setIssue(i);
    setTasks(t);
    setComments(c);
  }, [issueId]);

  useEffect(() => {
    void refresh();
  }, [refresh]);

  const onStatus = useCallback(
    async (status: IssueStatus) => {
      await updateIssue({ id: issueId, status });
      await refresh();
    },
    [issueId, refresh],
  );

  const onPriority = useCallback(
    async (priority: IssuePriority) => {
      await updateIssue({ id: issueId, priority });
      await refresh();
    },
    [issueId, refresh],
  );

  const onToggleTask = useCallback(
    async (task: IssueTask) => {
      await updateIssueTask({ id: task.id, is_done: !task.is_done });
      await refresh();
    },
    [refresh],
  );

  const onAddTask = useCallback(async () => {
    const title = newTask.trim();
    if (!title) return;
    setNewTask('');
    await createIssueTask({ issue_id: issueId, title });
    await refresh();
  }, [newTask, issueId, refresh]);

  const onAddComment = useCallback(async () => {
    const body = newComment.trim();
    if (!body) return;
    setNewComment('');
    await createIssueComment({ issue_id: issueId, body });
    await refresh();
  }, [newComment, issueId, refresh]);

  if (!issue) {
    return (
      <View style={styles.center}>
        <Text style={{ color: '#666' }}>Cargando…</Text>
      </View>
    );
  }

  const done = tasks.filter((t) => t.is_done).length;
  const progress = tasks.length ? Math.round((done / tasks.length) * 100) : 0;

  return (
    <ScrollView contentContainerStyle={styles.body}>
      <Text style={styles.title}>{issue.title}</Text>
      <View style={styles.badges}>
        {issue.status && (
          <Badge label={issue.status} color={ISSUE_STATUS_COLOR[issue.status] ?? '#666'} />
        )}
        {issue.priority && (
          <Badge
            label={issue.priority}
            color={ISSUE_PRIORITY_COLOR[issue.priority] ?? '#666'}
          />
        )}
        {issue.type && <Badge label={issue.type} color="#666" />}
      </View>
      {issue.description ? <Text style={styles.desc}>{issue.description}</Text> : null}

      <MediaStrip parentEntity="issue" parentId={issue.id} canUpload={hasPermission(user, 'upload media')} />

      {canEdit && (
        <Card style={styles.editCard}>
          <ChipSelect
            label="Estado"
            value={issue.status}
            options={STATUSES}
            onChange={(v) => void onStatus(v)}
          />
          <ChipSelect
            label="Prioridad"
            value={issue.priority}
            options={PRIORITIES}
            onChange={(v) => void onPriority(v)}
          />
        </Card>
      )}

      <SectionTitle>
        Tareas · {done}/{tasks.length} ({progress}%)
      </SectionTitle>
      {tasks.length === 0 && <EmptyState text="Sin tareas." />}
      {tasks.map((t) => (
        <TouchableOpacity
          key={t.id}
          style={styles.taskRow}
          disabled={!canEdit}
          onPress={() => void onToggleTask(t)}
        >
          <Text style={styles.checkbox}>{t.is_done ? '☑' : '☐'}</Text>
          <Text style={[styles.taskText, t.is_done && styles.taskDone]}>{t.title}</Text>
        </TouchableOpacity>
      ))}
      {canEdit && (
        <View style={styles.addRow}>
          <View style={{ flex: 1 }}>
            <Field
              label=""
              placeholder="Nueva tarea…"
              value={newTask}
              onChangeText={setNewTask}
              onSubmitEditing={() => void onAddTask()}
            />
          </View>
          <PrimaryButton title="Añadir" onPress={() => void onAddTask()} disabled={!newTask.trim()} />
        </View>
      )}

      <SectionTitle>Comentarios</SectionTitle>
      {comments.length === 0 && <EmptyState text="Sin comentarios." />}
      {comments.map((c) => (
        <Card key={c.id} style={styles.comment}>
          <Text style={styles.commentBody}>{c.body}</Text>
          {c.created_at ? (
            <Text style={styles.commentMeta}>{new Date(c.created_at).toLocaleString()}</Text>
          ) : null}
        </Card>
      ))}
      <View style={styles.addRow}>
        <View style={{ flex: 1 }}>
          <Field
            label=""
            placeholder="Escribe un comentario…"
            value={newComment}
            onChangeText={setNewComment}
            multiline
          />
        </View>
        <PrimaryButton
          title="Enviar"
          onPress={() => void onAddComment()}
          disabled={!newComment.trim()}
        />
      </View>
    </ScrollView>
  );
}

const styles = StyleSheet.create({
  center: { flex: 1, justifyContent: 'center', alignItems: 'center' },
  body: { padding: 16, gap: 4 },
  title: { fontSize: 20, fontWeight: '700' },
  badges: { flexDirection: 'row', gap: 6, marginTop: 6, flexWrap: 'wrap' },
  desc: { marginTop: 8, color: '#333', fontSize: 14 },
  editCard: { marginTop: 12, gap: 4 },
  taskRow: { flexDirection: 'row', alignItems: 'center', paddingVertical: 8, gap: 10 },
  checkbox: { fontSize: 20 },
  taskText: { fontSize: 15, flex: 1 },
  taskDone: { textDecorationLine: 'line-through', color: '#666' }, // muted
  addRow: { flexDirection: 'row', alignItems: 'flex-end', gap: 8, marginTop: 4 },
  comment: { marginBottom: 6 },
  commentBody: { fontSize: 14 },
  commentMeta: { fontSize: 11, color: '#666', marginTop: 4 }, // muted
});