package main

import (
	"context"
	"database/sql"
	"encoding/csv"
	"fmt"
	"log"
	"os"

	"faculty_media_report/dbi"
)

func main() {
	db, err := dbi.GetDbConn()
	if err != nil {
		log.Fatalf("GetDbConn: %v", err)
	}
	defer db.Close()

	conn, err := db.Conn(context.Background())
	if err != nil {
		log.Fatalf("db.Conn: %v", err)
	}
	defer conn.Close()

	if err := seedUsers(conn); err != nil {
		log.Fatalf("seed users: %v", err)
	}
	if err := seedAppearances(conn); err != nil {
		log.Fatalf("seed appearances: %v", err)
	}
	if err := seedActivities(conn); err != nil {
		log.Fatalf("seed activities: %v", err)
	}
	if err := seedScholarship(conn); err != nil {
		log.Fatalf("seed scholarship: %v", err)
	}
}

// readCSV reads filename and returns rows as header-keyed maps.
// Returns nil, nil if the file does not exist.
func readCSV(filename string) ([]map[string]string, error) {
	f, err := os.Open(filename)
	if os.IsNotExist(err) {
		return nil, nil
	}
	if err != nil {
		return nil, err
	}
	defer f.Close()

	records, err := csv.NewReader(f).ReadAll()
	if err != nil {
		return nil, fmt.Errorf("parse %s: %w", filename, err)
	}
	if len(records) < 2 {
		return nil, nil
	}

	headers := records[0]
	rows := make([]map[string]string, 0, len(records)-1)
	for _, rec := range records[1:] {
		row := make(map[string]string, len(headers))
		for i, h := range headers {
			if i < len(rec) {
				row[h] = rec[i]
			}
		}
		rows = append(rows, row)
	}
	return rows, nil
}

func seedUsers(conn *sql.Conn) error {
	rows, err := readCSV("users.csv")
	if err != nil {
		return err
	}
	for _, row := range rows {
		u := dbi.User{
			APIKey:    row["APIKey"],
			FirstName: row["FirstName"],
			LastName:  row["LastName"],
			Password:  row["Password"],
			Status:    row["Status"],
			Username:  row["Username"],
		}
		if err := dbi.CreateUser(conn, &u); err != nil {
			return fmt.Errorf("CreateUser %q: %w", u.Username, err)
		}
		log.Printf("created user %q", u.Username)
	}
	return nil
}

func seedAppearances(conn *sql.Conn) error {
	rows, err := readCSV("appearances.csv")
	if err != nil {
		return err
	}
	for _, row := range rows {
		a := dbi.Appearance{
			UID:         row["UID"],
			Title:       row["Title"],
			Description: row["Description"],
			Hyperlink:   row["Hyperlink"],
			Status:      row["Status"],
			Username:    row["Username"],
		}
		if err := dbi.CreateAppearance(conn, &a); err != nil {
			return fmt.Errorf("CreateAppearance %q: %w", a.Title, err)
		}
		log.Printf("created appearance %q", a.Title)
	}
	return nil
}

func seedActivities(conn *sql.Conn) error {
	rows, err := readCSV("activities.csv")
	if err != nil {
		return err
	}
	for _, row := range rows {
		a := dbi.Activity{
			UID:         row["UID"],
			Title:       row["Title"],
			Description: row["Description"],
			Hyperlink:   row["Hyperlink"],
			Status:      row["Status"],
			Username:    row["Username"],
		}
		if err := dbi.CreateActivity(conn, &a); err != nil {
			return fmt.Errorf("CreateActivity %q: %w", a.Title, err)
		}
		log.Printf("created activity %q", a.Title)
	}
	return nil
}

func seedScholarship(conn *sql.Conn) error {
	rows, err := readCSV("scholarship.csv")
	if err != nil {
		return err
	}
	for _, row := range rows {
		s := dbi.Scholarship{
			UID:       row["UID"],
			Citation:  row["Citation"],
			Hyperlink: row["Hyperlink"],
			DocumentLink: row["DocumentLink"],
			Status:    row["Status"],
			Username:  row["Username"],
		}
		if err := dbi.CreateScholarship(conn, &s); err != nil {
			return fmt.Errorf("CreateScholarship %q: %w", s.Citation, err)
		}
		log.Printf("created scholarship %q", s.Citation)
	}
	return nil
}