package calendar

import (
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"strings"
	"time"
)

type Holiday struct {
	Date string `json:"date"`
	Name string `json:"name"`
	Type string `json:"type"`
}

type Provider interface {
	NationalHolidays(ctx context.Context, year int) ([]Holiday, error)
}

type CommemorativeProvider interface {
	CommemorativeDates(ctx context.Context, year int) ([]ExternalCommemorativeDate, error)
}

type ExternalCommemorativeDate struct {
	Date        string
	Name        string
	Description string
	SourceID    string
}

type BrasilAPIProvider struct {
	baseURL string
	client  *http.Client
}

type FeriadosBrasilProvider struct {
	baseURL string
	client  *http.Client
}

func NewFeriadosBrasilProvider() FeriadosBrasilProvider {
	return FeriadosBrasilProvider{
		baseURL: "https://raw.githubusercontent.com/joaopbini/feriados-brasil/master/dados/comemorativas/json",
		client: &http.Client{
			Timeout: 10 * time.Second,
		},
	}
}

type feriadosBrasilCommemorativeDate struct {
	ID         string `json:"id"`
	Data       string `json:"data"`
	Nome       string `json:"nome"`
	Tipo       string `json:"tipo"`
	Descricao  string `json:"descricao"`
	UF         string `json:"uf"`
	CodigoIBGE *int   `json:"codigo_ibge"`
}

func (p FeriadosBrasilProvider) CommemorativeDates(ctx context.Context, year int) ([]ExternalCommemorativeDate, error) {
	url := fmt.Sprintf("%s/%d.json", p.baseURL, year)
	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
	if err != nil {
		return nil, err
	}

	resp, err := p.client.Do(req)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("feriados-brasil returned status %d", resp.StatusCode)
	}

	var records []feriadosBrasilCommemorativeDate
	if err := json.NewDecoder(resp.Body).Decode(&records); err != nil {
		return nil, err
	}

	dates := make([]ExternalCommemorativeDate, 0, len(records))
	for _, record := range records {
		if strings.ToUpper(strings.TrimSpace(record.Tipo)) != "COMEMORATIVA" {
			continue
		}
		parsed, err := time.Parse("02/01/2006", strings.TrimSpace(record.Data))
		if err != nil {
			continue
		}
		dates = append(dates, ExternalCommemorativeDate{
			Date:        parsed.Format("2006-01-02"),
			Name:        strings.TrimSpace(record.Nome),
			Description: strings.TrimSpace(record.Descricao),
			SourceID:    strings.TrimSpace(record.ID),
		})
	}

	return dates, nil
}

func NewBrasilAPIProvider(baseURL string) BrasilAPIProvider {
	return BrasilAPIProvider{
		baseURL: baseURL,
		client: &http.Client{
			Timeout: 10 * time.Second,
		},
	}
}

func (p BrasilAPIProvider) NationalHolidays(ctx context.Context, year int) ([]Holiday, error) {
	url := fmt.Sprintf("%s/api/feriados/v1/%d", p.baseURL, year)
	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
	if err != nil {
		return nil, err
	}

	resp, err := p.client.Do(req)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("brasilapi returned status %d", resp.StatusCode)
	}

	var holidays []Holiday
	if err := json.NewDecoder(resp.Body).Decode(&holidays); err != nil {
		return nil, err
	}

	return holidays, nil
}