package services

import (
	"database/sql"
	"fmt"
	"time"

	"github.com/HoHD/PR-Helper/models"
)

// SaveNote upserts a review note (insert or update if exists for the same analysis_id + scope + scope_key).
func SaveNote(db *sql.DB, analysisID int64, scope, scopeKey, content string) (*models.ReviewNote, error) {
	now := time.Now().UTC()

	// Try to find existing note
	var existingID int64
	err := db.QueryRow(`SELECT id FROM review_notes WHERE analysis_id = ? AND scope = ? AND scope_key = ?`,
		analysisID, scope, scopeKey).Scan(&existingID)

	if err == sql.ErrNoRows {
		// Insert new
		result, err := db.Exec(`INSERT INTO review_notes (analysis_id, scope, scope_key, content, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?)`,
			analysisID, scope, scopeKey, content, now, now)
		if err != nil {
			return nil, fmt.Errorf("insert note: %w", err)
		}
		id, _ := result.LastInsertId()
		return &models.ReviewNote{
			ID:         id,
			AnalysisID: analysisID,
			Scope:      scope,
			ScopeKey:   scopeKey,
			Content:    content,
			CreatedAt:  now,
			UpdatedAt:  now,
		}, nil
	}
	if err != nil {
		return nil, fmt.Errorf("query existing note: %w", err)
	}

	// Update existing
	_, err = db.Exec(`UPDATE review_notes SET content = ?, updated_at = ? WHERE id = ?`, content, now, existingID)
	if err != nil {
		return nil, fmt.Errorf("update note: %w", err)
	}

	return &models.ReviewNote{
		ID:         existingID,
		AnalysisID: analysisID,
		Scope:      scope,
		ScopeKey:   scopeKey,
		Content:    content,
		UpdatedAt:  now,
	}, nil
}

// GetNotes returns all review notes for a given analysis, optionally filtered by scope.
func GetNotes(db *sql.DB, analysisID int64, scope string) ([]models.ReviewNote, error) {
	var rows *sql.Rows
	var err error

	if scope != "" {
		rows, err = db.Query(`SELECT id, analysis_id, scope, scope_key, content, created_at, updated_at FROM review_notes WHERE analysis_id = ? AND scope = ? ORDER BY id`,
			analysisID, scope)
	} else {
		rows, err = db.Query(`SELECT id, analysis_id, scope, scope_key, content, created_at, updated_at FROM review_notes WHERE analysis_id = ? ORDER BY id`,
			analysisID)
	}
	if err != nil {
		return nil, fmt.Errorf("query notes: %w", err)
	}
	defer rows.Close()

	var notes []models.ReviewNote
	for rows.Next() {
		var n models.ReviewNote
		if err := rows.Scan(&n.ID, &n.AnalysisID, &n.Scope, &n.ScopeKey, &n.Content, &n.CreatedAt, &n.UpdatedAt); err != nil {
			continue
		}
		notes = append(notes, n)
	}
	return notes, nil
}

// DeleteNote deletes a specific review note by ID.
func DeleteNote(db *sql.DB, noteID int64) error {
	_, err := db.Exec(`DELETE FROM review_notes WHERE id = ?`, noteID)
	return err
}