package common

import (
	"bufio"
	"slices"
	"strings"
	"testing"
)

func newStringScanner(s string) *bufio.Scanner {
	return bufio.NewScanner(strings.NewReader(s))
}

func TestAssociatedPRScanner(t *testing.T) {
	t.Run("No PRs", func(t *testing.T) {
		if _, out := ExtractAssociatedDescriptionAndPRs(newStringScanner("")); len(out) != 0 {
			t.Error("Unexpected output", out)
		}
	})

	t.Run("Single PR", func(t *testing.T) {
		const singlePRText = `Some header of the issue

Followed by some description
PR: test/foo#4
`
		_, out := ExtractAssociatedDescriptionAndPRs(newStringScanner(singlePRText))
		if len(out) != 1 {
			t.Error("Unexpected output", out)
			return
		}

		expected := BasicPR{
			org:  "test",
			repo: "foo",
			num:  4,
		}
		if out[0] != expected {
			t.Error("Unexpected", out, "Expected", expected)
		}
	})

	t.Run("Multiple PRs", func(t *testing.T) {
		const multiplePRText = `Some header of the issue

Followed by some description
PR: test/foo#4

PR: test/goo#5
`

		_, out := ExtractAssociatedDescriptionAndPRs(newStringScanner(multiplePRText))
		if len(out) != 2 {
			t.Error("Unexpected output", out)
			return
		}

		expected1 := BasicPR{
			org:  "test",
			repo: "foo",
			num:  4,
		}
		expected2 := BasicPR{
			org:  "test",
			repo: "goo",
			num:  5,
		}

		if !slices.Contains(out, expected1) {
			t.Error("Unexpected", out, "Expected", expected1)
		}
		if !slices.Contains(out, expected2) {
			t.Error("Unexpected", out, "Expected", expected2)
		}
	})

	t.Run("Multiple PRs with whitespace", func(t *testing.T) {
		const whitespacePRText = `Some header of the issue

	PR: test/goo#5

    Followed by some description
	  PR: test/foo#4
`

		desc, out := ExtractAssociatedDescriptionAndPRs(newStringScanner(whitespacePRText))
		if len(out) != 2 {
			t.Error("Unexpected output", out)
			return
		}

		const expectedDesc = `Some header of the issue


    Followed by some description`
		expected1 := BasicPR{
			org:  "test",
			repo: "foo",
			num:  4,
		}
		expected2 := BasicPR{
			org:  "test",
			repo: "goo",
			num:  5,
		}

		if !slices.Contains(out, expected1) {
			t.Error("Unexpected", out, "Expected", expected1)
		}
		if !slices.Contains(out, expected2) {
			t.Error("Unexpected", out, "Expected", expected2)
		}
		if desc != expectedDesc {
			t.Error("unexpected desc", desc)
		}
	})

	t.Run("Multiple PRs with missing names and other special cases to ignore", func(t *testing.T) {
		const whitespacePRText = `Some header of the issue

    	PR: foobar#5 
    	PR: rd/goo5 
    	PR: test/#5 
    	PR: /goo#5 
    	PR: test/goo# 
    	PR: test / goo # 10
    	PR: test/gool# 10
    	PR: test/goo#5 

        Followed by some description
    	  PR: test/foo#4


		`

		desc, out := ExtractAssociatedDescriptionAndPRs(newStringScanner(whitespacePRText))
		if len(out) != 2 {
			t.Error("Unexpected output", out)
			return
		}

		const expectedDesc = `Some header of the issue

    	PR: foobar#5 
    	PR: rd/goo5 
    	PR: test/#5 
    	PR: /goo#5 
    	PR: test/goo# 
    	PR: test / goo # 10
    	PR: test/gool# 10

        Followed by some description`

		if desc != expectedDesc {
			t.Error(len(desc), "vs", len(expectedDesc))
			t.Error("description doesn't match expected. ", desc)
		}

		expected1 := BasicPR{
			org:  "test",
			repo: "foo",
			num:  4,
		}
		expected2 := BasicPR{
			org:  "test",
			repo: "goo",
			num:  5,
		}

		if !slices.Contains(out, expected1) {
			t.Error("Unexpected", out, "Expected", expected1)
		}
		if !slices.Contains(out, expected2) {
			t.Error("Unexpected", out, "Expected", expected2)
		}
	})

	t.Run("Append PRs to end of description", func(t *testing.T) {
		d := AppendPRsToDescription("something", []BasicPR{
			BasicPR{org: "a", repo: "b", num: 100},
		})

		const expectedDesc = `something

PR: a/b#100
`
		if d != expectedDesc {
			t.Error(len(d), "vs", len(expectedDesc))
			t.Error("unpected output", d)
		}
	})
}