package sms

import (
	"fmt"
	"strconv"
	"strings"
)

func (d *dialer) setupMsgSt() error {
	// Check for free space for messages
	// !!! I use one! memory for all three bindings
	// 1: read and delete
	// 2: sending
	// 3: write received

	// First try SM
	if _, err := d.port.Send(`AT+CPMS="SM","SM","SM"`); err != nil {
		return fmt.Errorf(`AT+CPMS="SM","SM","SM" request: %w`, err)
	}
	st, err := d.getCurMsgStSize()
	if err != nil {
		return fmt.Errorf("SM: %w", err)
	}
	if st[0].Used < st[0].Total {
		d.logger.Printf("Use SM message storage: %d/%d\n", st[0].Used, st[0].Total)
		return nil // There is space
	}
	d.logger.Printf("SM message storage is full: %d/%d\n", st[0].Used, st[0].Total)

	// Second try ME
	if _, err := d.port.Send(`AT+CPMS="ME","ME","ME"`); err != nil {
		return fmt.Errorf(`AT+CPMS="ME","ME","ME" request: %w`, err)
	}
	st, err = d.getCurMsgStSize()
	if err != nil {
		return fmt.Errorf("ME: %w", err)
	}
	if st[0].Used < st[0].Total {
		d.logger.Printf("Use ME message storage: %d/%d\n", st[0].Used, st[0].Total)
		return nil // There is space
	}
	d.logger.Printf("ME message storage is full: %d/%d\n", st[0].Used, st[0].Total)
	// Otherwise error
	return fmt.Errorf("all storages are full")
}

// Message storage
type msgSt struct {
	Name  string
	Used  int
	Total int
}

// Get size of used and total mem of current memory storage
func (d *dialer) getCurMsgStSize() ([]msgSt, error) {
	// Request
	resp, err := d.port.Send("AT+CPMS?")
	if err != nil {
		return nil, fmt.Errorf("AT+CPMS? request: %w", err)
	}
	// Check start and end
	if !resp.Check() && !resp.CheckFront("+CPMS:") {
		return nil, fmt.Errorf("AT+CPMS")
	}
	// Remove front and cut to values
	resp = resp.RmFront("+CPMS:")
	values := strings.Split(strings.ReplaceAll(strings.Split(resp.String(), "\n")[0], "\r", ""), ",")
	if len(values) != 9 {
		return nil, fmt.Errorf("CPMS response: invalid values count: [%s]", values)
	}

	// Parse values
	outMsgs := [3]msgSt{}
	for i := 0; i < 3; i++ {
		name := values[i]
		used, err := strconv.Atoi(values[i*3+1])
		if err != nil {
			return nil, fmt.Errorf("parse value #%d: %w", i+1, err)
		}
		total, err := strconv.Atoi(values[i*3+2])
		if err != nil {
			return nil, fmt.Errorf("parse value #%d, %w", i+2, err)
		}

		outMsgs[i] = msgSt{name, used, total}
	}
	return outMsgs[:], nil
}