package gocsvtable

import (
	"io"
	"reflect"
	"testing"
)

const testFile = "test.csv"

func TestOpenCSV(t *testing.T) {
	gct := GoCSVtable{}
	err := gct.OpenCSV(testFile)
	if err != nil {
		t.Errorf("\nError opening csv file:\n - %#v\n", err.Error())
	}
}

func TestGetHeader(t *testing.T) {
	const letters = 0
	const numbers = 1

	gct := GoCSVtable{}
	gct.OpenCSV(testFile)

	_, err := gct.GetHeader("Non Existent Field")
	if err == nil {
		t.Errorf("Getting header of non existent field should raise error.")
	}

	gotLettersCol, _ := gct.GetHeader("Letters")
	if gotLettersCol != letters {
		t.Errorf("Error reading correct 'Letters' column. Expected: '%v'. Got: '%v'.\n", letters, gotLettersCol)
	}

	gotNumbersCol, _ := gct.GetHeader("Numbers")
	if gotNumbersCol != numbers {
		t.Errorf("Error reading correct 'Numbers' column. Expected: '%v'. Got: '%v'.\n", numbers, gotNumbersCol)
	}
}

func TestNext(t *testing.T) {
	gct := GoCSVtable{}
	gct.OpenCSV(testFile)

	for row := 2; row < 5; row++ {
		err := gct.Next()
		if err != nil {
			t.Errorf("Error passing to next row. CSV file have 5 rows, not %v", row)
		}
	}

	// Try to go to different row, it should receive io.EOF
	err := gct.Next()
	if err != io.EOF {
		t.Errorf("Error on Next(), row should be inexistent. Expected: '%v'; Got: %v", io.EOF, err)
	}
}

func TestGetNumberOfRows(t *testing.T) {
	gct := GoCSVtable{}
	gct.OpenCSV(testFile)

	expected := 4 // 1 Header + 4 Data
	if gct.GetNumberOfRows() != expected {
		t.Errorf("Error getting number of rows in file. Expected: '%v'. Got: '%v'", expected, gct.GetNumberOfRows())
	}
}

func TestRead(t *testing.T) {
	gct := GoCSVtable{}
	gct.OpenCSV(testFile)

	row := 2
	expected := "b"

	gct.Row = row
	got, err := gct.Read("Letters")
	if err != nil {
		t.Errorf("%v", err.Error())
	}
	if got != expected {
		t.Errorf("Error getting correct field on row '%v'. Expected: '%v'. Got: '%v'", row, expected, got)
	}

	expected = "2"
	got, err = gct.Read("Numbers")
	if err != nil {
		t.Errorf("%v", err.Error())
	}
	if got != expected {
		t.Errorf("Error getting correct field on row '%v'. Expected: '%v'. Got: '%v'", row, expected, got)
	}
}

func TestReadRow(t *testing.T) {
	gct := GoCSVtable{}
	gct.OpenCSV(testFile)

	row := 3

	gct.Row = row
	got, err := gct.ReadRow(row)
	if err != nil {
		t.Errorf("Error getting correct row: '%v'", err.Error())
	}

	col, err := gct.GetHeader("Letters")
	if err != nil {
		t.Errorf("%v", err.Error())
	}
	gotLetter := got[col]
	expected := "c"
	if gotLetter != expected {
		t.Errorf("Error getting correct row. Expected: '[%v %v]'. Got: '%v'", expected, row, got)
	}

	col, err = gct.GetHeader("Numbers")
	if err != nil {
		t.Errorf("%v", err.Error())
	}
	gotNumber := got[col]
	expected = "3"
	if gotNumber != expected {
		t.Errorf("Error getting correct row. Expected: '[%v %v]'. Got: '%v'", expected, row, got)
	}

	row = 7
	got, err = gct.ReadRow(row)
	if err == nil {
		t.Errorf("Getting inexistent row should raise error. Value: '%v'. Error: '%v'", got, err)
	}
}

func TestReadCol(t *testing.T) {
	gct := GoCSVtable{}
	gct.OpenCSV(testFile)

	expected := []string{"a", "b", "c", "d"}
	col := "Letters"
	got, err := gct.ReadCol(col)
	if err != nil {
		t.Errorf("%v", err.Error())
	}

	if !reflect.DeepEqual(expected, got) {
		t.Errorf("Error getting column. Expected: '%v'. Got: '%v'", expected, got)
	}
}