package repository

import (
	"testing"
	"time"

	"github.com/daniil/homelab-api/internal/model"
)

func TestHabitFreezeRepository_CountFrozenDaysLogic(t *testing.T) {
	// Test the overlap calculation logic that CountFrozenDaysInRange uses
	tests := []struct {
		name       string
		freezeStart, freezeEnd time.Time
		queryStart, queryEnd   time.Time
		wantDays   int
	}{
		{
			name:        "full overlap",
			freezeStart: time.Date(2025, 1, 5, 0, 0, 0, 0, time.UTC),
			freezeEnd:   time.Date(2025, 1, 10, 0, 0, 0, 0, time.UTC),
			queryStart:  time.Date(2025, 1, 1, 0, 0, 0, 0, time.UTC),
			queryEnd:    time.Date(2025, 1, 31, 0, 0, 0, 0, time.UTC),
			wantDays:    6,
		},
		{
			name:        "partial overlap start",
			freezeStart: time.Date(2025, 1, 1, 0, 0, 0, 0, time.UTC),
			freezeEnd:   time.Date(2025, 1, 10, 0, 0, 0, 0, time.UTC),
			queryStart:  time.Date(2025, 1, 5, 0, 0, 0, 0, time.UTC),
			queryEnd:    time.Date(2025, 1, 31, 0, 0, 0, 0, time.UTC),
			wantDays:    6,
		},
		{
			name:        "partial overlap end",
			freezeStart: time.Date(2025, 1, 20, 0, 0, 0, 0, time.UTC),
			freezeEnd:   time.Date(2025, 2, 5, 0, 0, 0, 0, time.UTC),
			queryStart:  time.Date(2025, 1, 1, 0, 0, 0, 0, time.UTC),
			queryEnd:    time.Date(2025, 1, 31, 0, 0, 0, 0, time.UTC),
			wantDays:    12,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			freeze := model.HabitFreeze{
				StartDate: tt.freezeStart,
				EndDate:   tt.freezeEnd,
			}

			overlapStart := freeze.StartDate
			if tt.queryStart.After(freeze.StartDate) {
				overlapStart = tt.queryStart
			}
			overlapEnd := freeze.EndDate
			if tt.queryEnd.Before(freeze.EndDate) {
				overlapEnd = tt.queryEnd
			}

			days := 0
			if !overlapEnd.Before(overlapStart) {
				days = int(overlapEnd.Sub(overlapStart).Hours()/24) + 1
			}

			if days != tt.wantDays {
				t.Errorf("got %d frozen days, want %d", days, tt.wantDays)
			}
		})
	}
}

func TestJoinStrings(t *testing.T) {
	tests := []struct {
		input []string
		sep   string
		want  string
	}{
		{nil, ", ", ""},
		{[]string{"a"}, ", ", "a"},
		{[]string{"a", "b", "c"}, ", ", "a, b, c"},
		{[]string{"x", "y"}, " AND ", "x AND y"},
	}

	for _, tt := range tests {
		got := joinStrings(tt.input, tt.sep)
		if got != tt.want {
			t.Errorf("joinStrings(%v, %q) = %q, want %q", tt.input, tt.sep, got, tt.want)
		}
	}
}

func TestIsUniqueViolation(t *testing.T) {
	if isUniqueViolation(nil) {
		t.Error("nil error should not be unique violation")
	}
}