package discord

import (
	"context"
	"database/sql"
	"strings"
	"sync"
	"time"

	"plumber/internal/store"
)

// memoryLinks is an in-process DiscordLinkStore for tests.
type memoryLinks struct {
	mu        sync.Mutex
	byPost    map[string]store.DiscordLink
	byMessage map[string]string
	byThread  map[string]string
}

func newMemoryLinks() *memoryLinks {
	return &memoryLinks{
		byPost:    map[string]store.DiscordLink{},
		byMessage: map[string]string{},
		byThread:  map[string]string{},
	}
}

func (m *memoryLinks) GetByPostID(_ context.Context, postID string) (*store.DiscordLink, error) {
	m.mu.Lock()
	defer m.mu.Unlock()
	link, ok := m.byPost[strings.TrimSpace(postID)]
	if !ok {
		return nil, sql.ErrNoRows
	}
	cp := link
	return &cp, nil
}

func (m *memoryLinks) GetByMessageID(_ context.Context, messageID string) (*store.DiscordLink, error) {
	m.mu.Lock()
	defer m.mu.Unlock()
	postID, ok := m.byMessage[strings.TrimSpace(messageID)]
	if !ok {
		return nil, sql.ErrNoRows
	}
	link := m.byPost[postID]
	cp := link
	return &cp, nil
}

func (m *memoryLinks) GetRootByThreadID(_ context.Context, threadID string) (*store.DiscordLink, error) {
	m.mu.Lock()
	defer m.mu.Unlock()
	postID, ok := m.byThread[strings.TrimSpace(threadID)]
	if !ok {
		return nil, sql.ErrNoRows
	}
	link := m.byPost[postID]
	cp := link
	return &cp, nil
}

func (m *memoryLinks) Upsert(_ context.Context, link store.DiscordLink) error {
	m.mu.Lock()
	defer m.mu.Unlock()
	link.PostID = strings.TrimSpace(link.PostID)
	link.MessageID = strings.TrimSpace(link.MessageID)
	link.ThreadID = strings.TrimSpace(link.ThreadID)
	if link.CreatedAt == "" {
		link.CreatedAt = time.Now().UTC().Format(time.RFC3339Nano)
	}
	if prev, ok := m.byPost[link.PostID]; ok {
		delete(m.byMessage, prev.MessageID)
		if prev.ThreadID != "" {
			delete(m.byThread, prev.ThreadID)
		}
		if link.ThreadID == "" {
			link.ThreadID = prev.ThreadID
		}
	}
	m.byPost[link.PostID] = link
	m.byMessage[link.MessageID] = link.PostID
	if link.ThreadID != "" {
		m.byThread[link.ThreadID] = link.PostID
	}
	return nil
}