package utils

import (
	"os"
	"path/filepath"
	"testing"

	"github.com/stretchr/testify/assert"
)

func TestLimitString(t *testing.T) {
	tests := []struct {
		name     string
		input    string
		maxLen   int
		expected string
	}{
		{
			name:     "Short string",
			input:    "hello",
			maxLen:   10,
			expected: "hello",
		},
		{
			name:     "Exact length",
			input:    "hello",
			maxLen:   5,
			expected: "hello",
		},
		{
			name:     "Too long",
			input:    "hello world",
			maxLen:   8,
			expected: "hello...",
		},
		{
			name:     "With newlines",
			input:    "hello\nworld",
			maxLen:   20,
			expected: "hello\\nworld",
		},
		{
			name:     "With newlines truncated",
			input:    "hello\nworld\nfoo\nbar",
			maxLen:   15,
			expected: "hello\\nworld...",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			result := LimitString(tt.input, tt.maxLen)
			assert.Equal(t, tt.expected, result)
		})
	}
}

func TestResetWhereNecessary(t *testing.T) {
	tmpDir, err := os.MkdirTemp("", "reset-test-*")
	assert.NoError(t, err)
	defer os.RemoveAll(tmpDir)

	// Create test files
	file1 := filepath.Join(tmpDir, "file1.txt")
	file2 := filepath.Join(tmpDir, "file2.txt")
	file3 := filepath.Join(tmpDir, "file3.txt")

	err = os.WriteFile(file1, []byte("original1"), 0644)
	assert.NoError(t, err)
	err = os.WriteFile(file2, []byte("original2"), 0644)
	assert.NoError(t, err)
	err = os.WriteFile(file3, []byte("original3"), 0644)
	assert.NoError(t, err)

	// Modify files
	err = os.WriteFile(file1, []byte("modified1"), 0644)
	assert.NoError(t, err)
	err = os.WriteFile(file2, []byte("modified2"), 0644)
	assert.NoError(t, err)

	// Create mock DB
	db, err := GetDB()
	assert.NoError(t, err)
	err = db.SaveFile(file1, []byte("original1"))
	assert.NoError(t, err)
	err = db.SaveFile(file2, []byte("original2"))
	assert.NoError(t, err)
	// file3 not in DB

	// Create associations with reset commands
	associations := map[string]FileCommandAssociation{
		file1: {
			File: file1,
			Commands: []ModifyCommand{
				{Name: "cmd1", Reset: true},
			},
		},
		file2: {
			File: file2,
			IsolateCommands: []ModifyCommand{
				{Name: "cmd2", Reset: true},
			},
		},
		file3: {
			File: file3,
			Commands: []ModifyCommand{
				{Name: "cmd3", Reset: false}, // No reset
			},
		},
	}

	// Run reset
	err = ResetWhereNecessary(associations, db)
	assert.NoError(t, err)

	// Verify file1 was reset
	data, _ := os.ReadFile(file1)
	assert.Equal(t, "original1", string(data))

	// Verify file2 was reset
	data, _ = os.ReadFile(file2)
	assert.Equal(t, "original2", string(data))

	// Verify file3 was NOT reset
	data, _ = os.ReadFile(file3)
	assert.Equal(t, "original3", string(data))
}

func TestResetWhereNecessaryMissingFromDB(t *testing.T) {
	tmpDir, err := os.MkdirTemp("", "reset-missing-test-*")
	assert.NoError(t, err)
	defer os.RemoveAll(tmpDir)

	// Create a test file that's been modified
	file1 := filepath.Join(tmpDir, "file1.txt")
	err = os.WriteFile(file1, []byte("modified_content"), 0644)
	assert.NoError(t, err)

	// Create DB but DON'T save file to it
	db, err := GetDB()
	assert.NoError(t, err)

	// Create associations with reset command
	associations := map[string]FileCommandAssociation{
		file1: {
			File: file1,
			Commands: []ModifyCommand{
				{Name: "cmd1", Reset: true},
			},
		},
	}

	// Run reset - should use current disk content as fallback
	err = ResetWhereNecessary(associations, db)
	assert.NoError(t, err)

	// Verify file was "reset" to current content (saved to DB for next time)
	data, _ := os.ReadFile(file1)
	assert.Equal(t, "modified_content", string(data))

	// Verify it was saved to DB
	savedData, err := db.GetFile(file1)
	assert.NoError(t, err)
	assert.Equal(t, "modified_content", string(savedData))
}

func TestResetAllFiles(t *testing.T) {
	tmpDir, err := os.MkdirTemp("", "reset-all-test-*")
	assert.NoError(t, err)
	defer os.RemoveAll(tmpDir)

	// Create test files
	file1 := filepath.Join(tmpDir, "file1.txt")
	file2 := filepath.Join(tmpDir, "file2.txt")

	err = os.WriteFile(file1, []byte("original1"), 0644)
	assert.NoError(t, err)
	err = os.WriteFile(file2, []byte("original2"), 0644)
	assert.NoError(t, err)

	// Create mock DB and save originals
	db, err := GetDB()
	assert.NoError(t, err)
	err = db.SaveFile(file1, []byte("original1"))
	assert.NoError(t, err)
	err = db.SaveFile(file2, []byte("original2"))
	assert.NoError(t, err)

	// Modify files
	err = os.WriteFile(file1, []byte("modified1"), 0644)
	assert.NoError(t, err)
	err = os.WriteFile(file2, []byte("modified2"), 0644)
	assert.NoError(t, err)

	// Verify they're modified
	data, _ := os.ReadFile(file1)
	assert.Equal(t, "modified1", string(data))

	// Reset all
	err = ResetAllFiles(db)
	assert.NoError(t, err)

	// Verify both were reset
	data, _ = os.ReadFile(file1)
	assert.Equal(t, "original1", string(data))

	data, _ = os.ReadFile(file2)
	assert.Equal(t, "original2", string(data))
}