Implement entity structs for Kanboard API responses

Add all entity structs matching Kanboard's JSON-RPC API format:

Entity structs:
- Project, Task, Column, Category, Comment
- TaskLink, TaskFile, Tag
- TaskStatus enum (StatusActive, StatusInactive)

Request structs:
- CreateTaskRequest with omitempty for optional fields
- UpdateTaskRequest with pointer fields for zero-value distinction

Custom JSON types for Kanboard's string-encoded values:
- StringBool - handles "0"/"1" string booleans
- StringInt - handles string-encoded integers
- StringInt64 - handles string-encoded int64 values

All structs properly handle Kanboard's quirky JSON format where
numeric fields are often returned as quoted strings.

Closes: kanboard-api-cyc

.beads/issues.jsonl

@@ -10,7 +10,7 @@
 {"id":"kanboard-api-9k8","title":"Implement TaskParams builder (Options Pattern)","description":"Implement TaskParams for fluent task creation configuration.\n\n## Requirements\n- TaskParams struct with private fields\n- NewTask(title string) *TaskParams constructor\n- Fluent setter methods:\n  - WithDescription(desc string) *TaskParams\n  - InColumn(columnID int) *TaskParams\n  - WithCategory(categoryID int) *TaskParams\n  - WithOwner(ownerID int) *TaskParams\n  - WithColor(colorID string) *TaskParams\n  - WithPriority(priority int) *TaskParams\n  - WithDueDate(date time.Time) *TaskParams\n  - WithTags(tags ...string) *TaskParams\n  - WithReference(ref string) *TaskParams\n- Internal method to convert to CreateTaskRequest\n\n## Files to create\n- task_params.go\n\n## Example usage\n```go\nparams := kanboard.NewTask(\"My Task\").\n    WithDescription(\"Details\").\n    InColumn(2).\n    WithTags(\"urgent\", \"backend\")\n```\n\n## Acceptance criteria\n- Pure configuration object (no I/O)\n- All setters return *TaskParams for chaining\n- Unset optional fields remain nil","status":"open","priority":1,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:35:40.439513879+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T17:35:40.439513879+01:00","dependencies":[{"issue_id":"kanboard-api-9k8","depends_on_id":"kanboard-api-cyc","type":"blocks","created_at":"2026-01-15T17:43:31.070100884+01:00","created_by":"Oliver Jakoubek"}]}
 {"id":"kanboard-api-apl","title":"Implement Project API methods","description":"Implement direct API methods for project/board operations.\n\n## Methods to implement\n- GetAllProjects(ctx) ([]Project, error) - getAllProjects\n- GetProjectByID(ctx, projectID int) (*Project, error) - getProjectById\n- GetProjectByName(ctx, name string) (*Project, error) - getProjectByName (Nice-to-have)\n\n## Files to create\n- projects.go\n\n## Acceptance criteria\n- All methods use context for cancellation\n- Proper error handling and wrapping\n- Returns ErrProjectNotFound when appropriate","status":"open","priority":1,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:35:15.864764497+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T17:35:15.864764497+01:00","dependencies":[{"issue_id":"kanboard-api-apl","depends_on_id":"kanboard-api-uls","type":"blocks","created_at":"2026-01-15T17:42:52.850751716+01:00","created_by":"Oliver Jakoubek"},{"issue_id":"kanboard-api-apl","depends_on_id":"kanboard-api-cyc","type":"blocks","created_at":"2026-01-15T17:42:52.946556814+01:00","created_by":"Oliver Jakoubek"}]}
 {"id":"kanboard-api-c3i","title":"Create README.md with documentation","description":"Create comprehensive README.md documentation in English.\n\n## Sections to include\n- Project overview and features\n- Installation instructions\n- Quick start example\n- API documentation overview\n- Authentication methods (API token, user/password)\n- Fluent API examples\n- Direct API examples\n- Error handling\n- Thread-safety notes\n- Tag operations warning (non-atomic)\n- License (MIT)\n\n## Example code to include\n```go\n// Client creation\nclient := kanboard.NewClient(\"https://kanboard.example.com\").\n    WithAPIToken(\"my-token\").\n    WithTimeout(30 * time.Second)\n\n// Fluent API\ntask, _ := client.Board(1).CreateTask(ctx,\n    kanboard.NewTask(\"My Task\").WithDescription(\"Details\"))\n\n// Direct API\ntasks, _ := client.GetAllTasks(ctx, 1, kanboard.StatusActive)\n```\n\n## Files to create\n- README.md\n\n## Acceptance criteria\n- Clear installation instructions\n- Working code examples\n- Documents all major features","status":"open","priority":2,"issue_type":"task","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:36:53.228407343+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T17:36:53.228407343+01:00","dependencies":[{"issue_id":"kanboard-api-c3i","depends_on_id":"kanboard-api-uls","type":"blocks","created_at":"2026-01-15T17:46:55.445847253+01:00","created_by":"Oliver Jakoubek"}]}
-{"id":"kanboard-api-cyc","title":"Implement entity structs (types.go)","description":"Implement all entity structs for Kanboard API responses.\n\n## Structs to implement\n- Project (ID, Name, Description, IsActive, Token, LastModified, etc.)\n- Task (ID, Title, Description, dates, ColorID, ProjectID, ColumnID, etc.)\n- Column (ID, Title, Position, ProjectID, TaskLimit, Description)\n- Category (ID, Name, ProjectID, ColorID)\n- Comment (ID, TaskID, UserID, DateCreation, Content, Username, etc.)\n- TaskLink (ID, LinkID, TaskID, OppositeTaskID, Label, Title)\n- TaskFile (ID, Name, Path, IsImage, TaskID, DateCreation, UserID, Size)\n- Tag (ID, Name, ProjectID, ColorID)\n- TaskStatus enum (StatusActive, StatusInactive)\n\n## Request structs\n- CreateTaskRequest\n- UpdateTaskRequest (with pointer fields for optional values)\n\n## Files to create\n- types.go\n\n## Acceptance criteria\n- All JSON tags match Kanboard API\n- Optional fields use pointers with omitempty\n- Timestamp fields use custom Timestamp type","status":"open","priority":0,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:34:55.484472208+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T17:34:55.484472208+01:00","dependencies":[{"issue_id":"kanboard-api-cyc","depends_on_id":"kanboard-api-25y","type":"blocks","created_at":"2026-01-15T17:42:48.385166815+01:00","created_by":"Oliver Jakoubek"}]}
+{"id":"kanboard-api-cyc","title":"Implement entity structs (types.go)","description":"Implement all entity structs for Kanboard API responses.\n\n## Structs to implement\n- Project (ID, Name, Description, IsActive, Token, LastModified, etc.)\n- Task (ID, Title, Description, dates, ColorID, ProjectID, ColumnID, etc.)\n- Column (ID, Title, Position, ProjectID, TaskLimit, Description)\n- Category (ID, Name, ProjectID, ColorID)\n- Comment (ID, TaskID, UserID, DateCreation, Content, Username, etc.)\n- TaskLink (ID, LinkID, TaskID, OppositeTaskID, Label, Title)\n- TaskFile (ID, Name, Path, IsImage, TaskID, DateCreation, UserID, Size)\n- Tag (ID, Name, ProjectID, ColorID)\n- TaskStatus enum (StatusActive, StatusInactive)\n\n## Request structs\n- CreateTaskRequest\n- UpdateTaskRequest (with pointer fields for optional values)\n\n## Files to create\n- types.go\n\n## Acceptance criteria\n- All JSON tags match Kanboard API\n- Optional fields use pointers with omitempty\n- Timestamp fields use custom Timestamp type","status":"closed","priority":0,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:34:55.484472208+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T18:18:40.163015715+01:00","closed_at":"2026-01-15T18:18:40.163015715+01:00","close_reason":"Closed","dependencies":[{"issue_id":"kanboard-api-cyc","depends_on_id":"kanboard-api-25y","type":"blocks","created_at":"2026-01-15T17:42:48.385166815+01:00","created_by":"Oliver Jakoubek"}]}
 {"id":"kanboard-api-fue","title":"Implement Task search and move methods","description":"Implement task search and movement API methods.\n\n## Methods to implement\n- SearchTasks(ctx, projectID int, query string) ([]Task, error) - searchTasks\n- MoveTaskPosition(ctx, projectID, taskID, columnID, position, swimlaneID int) error - moveTaskPosition\n- MoveTaskToProject(ctx, taskID, projectID int) error - moveTaskToProject\n\n## Files to create\n- tasks.go (extend)\n\n## Acceptance criteria\n- Search supports Kanboard query syntax\n- MoveTaskPosition handles column and position\n- Proper error handling for invalid moves","status":"open","priority":1,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:35:17.380817511+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T17:35:17.380817511+01:00","dependencies":[{"issue_id":"kanboard-api-fue","depends_on_id":"kanboard-api-91a","type":"blocks","created_at":"2026-01-15T17:42:53.59290181+01:00","created_by":"Oliver Jakoubek"}]}
 {"id":"kanboard-api-h4u","title":"Implement Comment API methods","description":"Implement direct API methods for comment operations.\n\n## Methods to implement\n- GetAllComments(ctx, taskID int) ([]Comment, error) - getAllComments\n- CreateComment(ctx, taskID, userID int, content string) (*Comment, error) - createComment\n- UpdateComment(ctx, commentID int, content string) error - updateComment\n- RemoveComment(ctx, commentID int) error - removeComment\n\n## TaskScope methods to add\n- AddComment(ctx, content string) (*Comment, error)\n- GetComments(ctx) ([]Comment, error)\n\n## Files to create\n- comments.go\n- task_scope.go (extend)\n\n## Acceptance criteria\n- CreateComment returns the created comment\n- Returns ErrCommentNotFound when appropriate","status":"open","priority":1,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:36:08.156950163+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T17:36:08.156950163+01:00","dependencies":[{"issue_id":"kanboard-api-h4u","depends_on_id":"kanboard-api-uls","type":"blocks","created_at":"2026-01-15T17:43:48.898295911+01:00","created_by":"Oliver Jakoubek"},{"issue_id":"kanboard-api-h4u","depends_on_id":"kanboard-api-cyc","type":"blocks","created_at":"2026-01-15T17:43:49.058259216+01:00","created_by":"Oliver Jakoubek"}]}
 {"id":"kanboard-api-k33","title":"Implement authentication system","description":"Implement HTTP Basic Auth support for both API token and user/password authentication.\n\n## Requirements\n- Authenticator interface for auth strategies\n- API Token auth: HTTP Basic with username `jsonrpc` and API token as password\n- User/Password auth: HTTP Basic with username and password\n- WithAPIToken(token string) fluent method\n- WithBasicAuth(username, password string) fluent method\n- Secure handling - no credential storage/logging\n\n## Files to create\n- auth.go\n\n## Acceptance criteria\n- Both auth methods work correctly\n- Credentials properly encoded in Authorization header\n- No sensitive data logged","status":"closed","priority":0,"issue_type":"feature","owner":"mail@oliverjakoubek.de","created_at":"2026-01-15T17:34:53.631074781+01:00","created_by":"Oliver Jakoubek","updated_at":"2026-01-15T18:11:42.58778642+01:00","closed_at":"2026-01-15T18:11:42.58778642+01:00","close_reason":"Closed"}

types.go

@@ -0,0 +1,257 @@
+package kanboard
+
+import (
+	"encoding/json"
+	"strconv"
+)
+
+// TaskStatus represents the status of a task.
+type TaskStatus int
+
+const (
+	// StatusActive represents an open/active task.
+	StatusActive TaskStatus = 1
+	// StatusInactive represents a closed/inactive task.
+	StatusInactive TaskStatus = 0
+)
+
+// StringBool is a bool that can be unmarshaled from a string "0" or "1".
+type StringBool bool
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (b *StringBool) UnmarshalJSON(data []byte) error {
+	var s string
+	if err := json.Unmarshal(data, &s); err != nil {
+		// Try as raw bool
+		var boolVal bool
+		if err := json.Unmarshal(data, &boolVal); err != nil {
+			return err
+		}
+		*b = StringBool(boolVal)
+		return nil
+	}
+	*b = s == "1" || s == "true"
+	return nil
+}
+
+// MarshalJSON implements json.Marshaler.
+func (b StringBool) MarshalJSON() ([]byte, error) {
+	if b {
+		return []byte(`"1"`), nil
+	}
+	return []byte(`"0"`), nil
+}
+
+// StringInt is an int that can be unmarshaled from a JSON string.
+type StringInt int
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (i *StringInt) UnmarshalJSON(data []byte) error {
+	var s string
+	if err := json.Unmarshal(data, &s); err != nil {
+		// Try as raw int
+		var intVal int
+		if err := json.Unmarshal(data, &intVal); err != nil {
+			return err
+		}
+		*i = StringInt(intVal)
+		return nil
+	}
+	if s == "" {
+		*i = 0
+		return nil
+	}
+	val, err := strconv.Atoi(s)
+	if err != nil {
+		return err
+	}
+	*i = StringInt(val)
+	return nil
+}
+
+// StringInt64 is an int64 that can be unmarshaled from a JSON string.
+type StringInt64 int64
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (i *StringInt64) UnmarshalJSON(data []byte) error {
+	var s string
+	if err := json.Unmarshal(data, &s); err != nil {
+		// Try as raw int64
+		var intVal int64
+		if err := json.Unmarshal(data, &intVal); err != nil {
+			return err
+		}
+		*i = StringInt64(intVal)
+		return nil
+	}
+	if s == "" {
+		*i = 0
+		return nil
+	}
+	val, err := strconv.ParseInt(s, 10, 64)
+	if err != nil {
+		return err
+	}
+	*i = StringInt64(val)
+	return nil
+}
+
+// Project represents a Kanboard project (board).
+type Project struct {
+	ID                  StringInt  `json:"id"`
+	Name                string     `json:"name"`
+	Description         string     `json:"description"`
+	IsActive            StringBool `json:"is_active"`
+	Token               string     `json:"token"`
+	LastModified        Timestamp  `json:"last_modified"`
+	IsPublic            StringBool `json:"is_public"`
+	IsPrivate           StringBool `json:"is_private"`
+	DefaultSwimlane     string     `json:"default_swimlane"`
+	ShowDefaultSwimlane StringBool `json:"show_default_swimlane"`
+	Identifier          string     `json:"identifier"`
+	StartDate           Timestamp  `json:"start_date"`
+	EndDate             Timestamp  `json:"end_date"`
+	OwnerID             StringInt  `json:"owner_id"`
+	PriorityDefault     StringInt  `json:"priority_default"`
+	PriorityStart       StringInt  `json:"priority_start"`
+	PriorityEnd         StringInt  `json:"priority_end"`
+	Email               string     `json:"email"`
+}
+
+// Task represents a Kanboard task.
+type Task struct {
+	ID                  StringInt  `json:"id"`
+	Title               string     `json:"title"`
+	Description         string     `json:"description"`
+	DateCreation        Timestamp  `json:"date_creation"`
+	DateModification    Timestamp  `json:"date_modification"`
+	DateCompleted       Timestamp  `json:"date_completed"`
+	DateStarted         Timestamp  `json:"date_started"`
+	DateDue             Timestamp  `json:"date_due"`
+	ColorID             string     `json:"color_id"`
+	ProjectID           StringInt  `json:"project_id"`
+	ColumnID            StringInt  `json:"column_id"`
+	OwnerID             StringInt  `json:"owner_id"`
+	CreatorID           StringInt  `json:"creator_id"`
+	Position            StringInt  `json:"position"`
+	IsActive            StringBool `json:"is_active"`
+	Score               StringInt  `json:"score"`
+	CategoryID          StringInt  `json:"category_id"`
+	SwimlaneID          StringInt  `json:"swimlane_id"`
+	Priority            StringInt  `json:"priority"`
+	Reference           string     `json:"reference"`
+	RecurrenceStatus    StringInt  `json:"recurrence_status"`
+	RecurrenceTrigger   StringInt  `json:"recurrence_trigger"`
+	RecurrenceFactor    StringInt  `json:"recurrence_factor"`
+	RecurrenceTimeframe StringInt  `json:"recurrence_timeframe"`
+	RecurrenceBasedate  StringInt  `json:"recurrence_basedate"`
+	RecurrenceParent    StringInt  `json:"recurrence_parent"`
+	RecurrenceChild     StringInt  `json:"recurrence_child"`
+}
+
+// Column represents a Kanboard column.
+type Column struct {
+	ID          StringInt `json:"id"`
+	Title       string    `json:"title"`
+	Position    StringInt `json:"position"`
+	ProjectID   StringInt `json:"project_id"`
+	TaskLimit   StringInt `json:"task_limit"`
+	Description string    `json:"description"`
+}
+
+// Category represents a Kanboard category.
+type Category struct {
+	ID        StringInt `json:"id"`
+	Name      string    `json:"name"`
+	ProjectID StringInt `json:"project_id"`
+	ColorID   string    `json:"color_id"`
+}
+
+// Comment represents a Kanboard comment.
+type Comment struct {
+	ID           StringInt `json:"id"`
+	TaskID       StringInt `json:"task_id"`
+	UserID       StringInt `json:"user_id"`
+	DateCreation Timestamp `json:"date_creation"`
+	Content      string    `json:"comment"`
+	Username     string    `json:"username"`
+	Name         string    `json:"name"`
+	Email        string    `json:"email"`
+	AvatarPath   string    `json:"avatar_path"`
+}
+
+// TaskLink represents a link between two tasks.
+type TaskLink struct {
+	ID             StringInt `json:"id"`
+	LinkID         StringInt `json:"link_id"`
+	TaskID         StringInt `json:"task_id"`
+	OppositeTaskID StringInt `json:"opposite_task_id"`
+	Label          string    `json:"label"`
+	Title          string    `json:"title"`
+}
+
+// TaskFile represents a file attached to a task.
+type TaskFile struct {
+	ID           StringInt   `json:"id"`
+	Name         string      `json:"name"`
+	Path         string      `json:"path"`
+	IsImage      StringBool  `json:"is_image"`
+	TaskID       StringInt   `json:"task_id"`
+	DateCreation Timestamp   `json:"date_creation"`
+	UserID       StringInt   `json:"user_id"`
+	Size         StringInt64 `json:"size"`
+}
+
+// Tag represents a Kanboard tag.
+type Tag struct {
+	ID        StringInt `json:"id"`
+	Name      string    `json:"name"`
+	ProjectID StringInt `json:"project_id"`
+	ColorID   string    `json:"color_id"`
+}
+
+// CreateTaskRequest is the request payload for creating a task.
+type CreateTaskRequest struct {
+	Title               string   `json:"title"`
+	ProjectID           int      `json:"project_id"`
+	Description         string   `json:"description,omitempty"`
+	ColumnID            int      `json:"column_id,omitempty"`
+	OwnerID             int      `json:"owner_id,omitempty"`
+	CreatorID           int      `json:"creator_id,omitempty"`
+	ColorID             string   `json:"color_id,omitempty"`
+	CategoryID          int      `json:"category_id,omitempty"`
+	DateDue             int64    `json:"date_due,omitempty"`
+	Score               int      `json:"score,omitempty"`
+	SwimlaneID          int      `json:"swimlane_id,omitempty"`
+	Priority            int      `json:"priority,omitempty"`
+	Reference           string   `json:"reference,omitempty"`
+	Tags                []string `json:"tags,omitempty"`
+	DateStarted         int64    `json:"date_started,omitempty"`
+	RecurrenceStatus    int      `json:"recurrence_status,omitempty"`
+	RecurrenceTrigger   int      `json:"recurrence_trigger,omitempty"`
+	RecurrenceFactor    int      `json:"recurrence_factor,omitempty"`
+	RecurrenceTimeframe int      `json:"recurrence_timeframe,omitempty"`
+	RecurrenceBasedate  int      `json:"recurrence_basedate,omitempty"`
+}
+
+// UpdateTaskRequest is the request payload for updating a task.
+// Pointer fields allow distinguishing between "not set" and "set to zero value".
+type UpdateTaskRequest struct {
+	ID                  int      `json:"id"`
+	Title               *string  `json:"title,omitempty"`
+	Description         *string  `json:"description,omitempty"`
+	ColorID             *string  `json:"color_id,omitempty"`
+	OwnerID             *int     `json:"owner_id,omitempty"`
+	CategoryID          *int     `json:"category_id,omitempty"`
+	DateDue             *int64   `json:"date_due,omitempty"`
+	Score               *int     `json:"score,omitempty"`
+	Priority            *int     `json:"priority,omitempty"`
+	Reference           *string  `json:"reference,omitempty"`
+	DateStarted         *int64   `json:"date_started,omitempty"`
+	RecurrenceStatus    *int     `json:"recurrence_status,omitempty"`
+	RecurrenceTrigger   *int     `json:"recurrence_trigger,omitempty"`
+	RecurrenceFactor    *int     `json:"recurrence_factor,omitempty"`
+	RecurrenceTimeframe *int     `json:"recurrence_timeframe,omitempty"`
+	RecurrenceBasedate  *int     `json:"recurrence_basedate,omitempty"`
+	Tags                []string `json:"tags,omitempty"`
+}

types_test.go

@@ -0,0 +1,521 @@
+package kanboard
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+)
+
+func TestTaskStatus_Constants(t *testing.T) {
+	if StatusActive != 1 {
+		t.Errorf("expected StatusActive=1, got %d", StatusActive)
+	}
+	if StatusInactive != 0 {
+		t.Errorf("expected StatusInactive=0, got %d", StatusInactive)
+	}
+}
+
+func TestStringBool_UnmarshalJSON(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected bool
+	}{
+		{"string 1", `"1"`, true},
+		{"string 0", `"0"`, false},
+		{"string true", `"true"`, true},
+		{"string false", `"false"`, false},
+		{"bool true", `true`, true},
+		{"bool false", `false`, false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var b StringBool
+			if err := json.Unmarshal([]byte(tt.input), &b); err != nil {
+				t.Fatalf("unmarshal error: %v", err)
+			}
+			if bool(b) != tt.expected {
+				t.Errorf("expected %v, got %v", tt.expected, b)
+			}
+		})
+	}
+}
+
+func TestStringInt_UnmarshalJSON(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected int
+	}{
+		{"string number", `"42"`, 42},
+		{"string zero", `"0"`, 0},
+		{"int number", `42`, 42},
+		{"int zero", `0`, 0},
+		{"empty string", `""`, 0},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var i StringInt
+			if err := json.Unmarshal([]byte(tt.input), &i); err != nil {
+				t.Fatalf("unmarshal error: %v", err)
+			}
+			if int(i) != tt.expected {
+				t.Errorf("expected %v, got %v", tt.expected, i)
+			}
+		})
+	}
+}
+
+func TestStringInt64_UnmarshalJSON(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    string
+		expected int64
+	}{
+		{"string number", `"1048576"`, 1048576},
+		{"string zero", `"0"`, 0},
+		{"int64 number", `1048576`, 1048576},
+		{"int64 zero", `0`, 0},
+		{"empty string", `""`, 0},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var i StringInt64
+			if err := json.Unmarshal([]byte(tt.input), &i); err != nil {
+				t.Fatalf("unmarshal error: %v", err)
+			}
+			if int64(i) != tt.expected {
+				t.Errorf("expected %v, got %v", tt.expected, i)
+			}
+		})
+	}
+}
+
+func TestProject_UnmarshalJSON(t *testing.T) {
+	jsonData := `{
+		"id": "1",
+		"name": "Test Project",
+		"description": "A test project",
+		"is_active": "1",
+		"token": "abc123",
+		"last_modified": 1609459200,
+		"is_public": "0",
+		"is_private": "1",
+		"owner_id": "42",
+		"priority_default": "2"
+	}`
+
+	var project Project
+	if err := json.Unmarshal([]byte(jsonData), &project); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	if int(project.ID) != 1 {
+		t.Errorf("expected ID=1, got %d", project.ID)
+	}
+	if project.Name != "Test Project" {
+		t.Errorf("expected Name='Test Project', got %s", project.Name)
+	}
+	if !bool(project.IsActive) {
+		t.Error("expected IsActive=true")
+	}
+	if bool(project.IsPublic) {
+		t.Error("expected IsPublic=false")
+	}
+	if !bool(project.IsPrivate) {
+		t.Error("expected IsPrivate=true")
+	}
+	if int(project.OwnerID) != 42 {
+		t.Errorf("expected OwnerID=42, got %d", project.OwnerID)
+	}
+}
+
+func TestTask_UnmarshalJSON(t *testing.T) {
+	jsonData := `{
+		"id": "42",
+		"title": "Test Task",
+		"description": "Task description",
+		"date_creation": 1609459200,
+		"date_due": 0,
+		"color_id": "yellow",
+		"project_id": "1",
+		"column_id": "2",
+		"owner_id": "5",
+		"is_active": "1",
+		"priority": "2",
+		"category_id": "3"
+	}`
+
+	var task Task
+	if err := json.Unmarshal([]byte(jsonData), &task); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	if int(task.ID) != 42 {
+		t.Errorf("expected ID=42, got %d", task.ID)
+	}
+	if task.Title != "Test Task" {
+		t.Errorf("expected Title='Test Task', got %s", task.Title)
+	}
+	if int(task.ProjectID) != 1 {
+		t.Errorf("expected ProjectID=1, got %d", task.ProjectID)
+	}
+	if int(task.ColumnID) != 2 {
+		t.Errorf("expected ColumnID=2, got %d", task.ColumnID)
+	}
+	if !bool(task.IsActive) {
+		t.Error("expected IsActive=true")
+	}
+	if task.DateCreation.IsZero() {
+		t.Error("expected DateCreation to be set")
+	}
+	if !task.DateDue.IsZero() {
+		t.Error("expected DateDue to be zero")
+	}
+}
+
+func TestColumn_UnmarshalJSON(t *testing.T) {
+	jsonData := `{
+		"id": "1",
+		"title": "Backlog",
+		"position": "1",
+		"project_id": "5",
+		"task_limit": "10",
+		"description": "Tasks to be done"
+	}`
+
+	var column Column
+	if err := json.Unmarshal([]byte(jsonData), &column); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	if int(column.ID) != 1 {
+		t.Errorf("expected ID=1, got %d", column.ID)
+	}
+	if column.Title != "Backlog" {
+		t.Errorf("expected Title='Backlog', got %s", column.Title)
+	}
+	if int(column.Position) != 1 {
+		t.Errorf("expected Position=1, got %d", column.Position)
+	}
+	if int(column.TaskLimit) != 10 {
+		t.Errorf("expected TaskLimit=10, got %d", column.TaskLimit)
+	}
+}
+
+func TestCategory_UnmarshalJSON(t *testing.T) {
+	jsonData := `{
+		"id": "3",
+		"name": "Bug",
+		"project_id": "1",
+		"color_id": "red"
+	}`
+
+	var category Category
+	if err := json.Unmarshal([]byte(jsonData), &category); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	if int(category.ID) != 3 {
+		t.Errorf("expected ID=3, got %d", category.ID)
+	}
+	if category.Name != "Bug" {
+		t.Errorf("expected Name='Bug', got %s", category.Name)
+	}
+	if category.ColorID != "red" {
+		t.Errorf("expected ColorID='red', got %s", category.ColorID)
+	}
+}
+
+func TestComment_UnmarshalJSON(t *testing.T) {
+	jsonData := `{
+		"id": "10",
+		"task_id": "42",
+		"user_id": "5",
+		"date_creation": 1609459200,
+		"comment": "This is a comment",
+		"username": "admin",
+		"name": "Admin User",
+		"email": "admin@example.com"
+	}`
+
+	var comment Comment
+	if err := json.Unmarshal([]byte(jsonData), &comment); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	if int(comment.ID) != 10 {
+		t.Errorf("expected ID=10, got %d", comment.ID)
+	}
+	if int(comment.TaskID) != 42 {
+		t.Errorf("expected TaskID=42, got %d", comment.TaskID)
+	}
+	if comment.Content != "This is a comment" {
+		t.Errorf("expected Content='This is a comment', got %s", comment.Content)
+	}
+	if comment.Username != "admin" {
+		t.Errorf("expected Username='admin', got %s", comment.Username)
+	}
+}
+
+func TestTaskLink_UnmarshalJSON(t *testing.T) {
+	jsonData := `{
+		"id": "1",
+		"link_id": "2",
+		"task_id": "42",
+		"opposite_task_id": "43",
+		"label": "blocks",
+		"title": "Related Task"
+	}`
+
+	var link TaskLink
+	if err := json.Unmarshal([]byte(jsonData), &link); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	if int(link.ID) != 1 {
+		t.Errorf("expected ID=1, got %d", link.ID)
+	}
+	if int(link.TaskID) != 42 {
+		t.Errorf("expected TaskID=42, got %d", link.TaskID)
+	}
+	if int(link.OppositeTaskID) != 43 {
+		t.Errorf("expected OppositeTaskID=43, got %d", link.OppositeTaskID)
+	}
+	if link.Label != "blocks" {
+		t.Errorf("expected Label='blocks', got %s", link.Label)
+	}
+}
+
+func TestTaskFile_UnmarshalJSON(t *testing.T) {
+	jsonData := `{
+		"id": "1",
+		"name": "document.pdf",
+		"path": "/uploads/document.pdf",
+		"is_image": "0",
+		"task_id": "42",
+		"date_creation": 1609459200,
+		"user_id": "5",
+		"size": "1048576"
+	}`
+
+	var file TaskFile
+	if err := json.Unmarshal([]byte(jsonData), &file); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	if int(file.ID) != 1 {
+		t.Errorf("expected ID=1, got %d", file.ID)
+	}
+	if file.Name != "document.pdf" {
+		t.Errorf("expected Name='document.pdf', got %s", file.Name)
+	}
+	if bool(file.IsImage) {
+		t.Error("expected IsImage=false")
+	}
+	if int64(file.Size) != 1048576 {
+		t.Errorf("expected Size=1048576, got %d", file.Size)
+	}
+}
+
+func TestTag_UnmarshalJSON(t *testing.T) {
+	jsonData := `{
+		"id": "5",
+		"name": "urgent",
+		"project_id": "1",
+		"color_id": "red"
+	}`
+
+	var tag Tag
+	if err := json.Unmarshal([]byte(jsonData), &tag); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	if int(tag.ID) != 5 {
+		t.Errorf("expected ID=5, got %d", tag.ID)
+	}
+	if tag.Name != "urgent" {
+		t.Errorf("expected Name='urgent', got %s", tag.Name)
+	}
+	if tag.ColorID != "red" {
+		t.Errorf("expected ColorID='red', got %s", tag.ColorID)
+	}
+}
+
+func TestCreateTaskRequest_MarshalJSON(t *testing.T) {
+	req := CreateTaskRequest{
+		Title:       "New Task",
+		ProjectID:   1,
+		Description: "Task description",
+		ColumnID:    2,
+		Priority:    3,
+		Tags:        []string{"urgent", "backend"},
+	}
+
+	data, err := json.Marshal(req)
+	if err != nil {
+		t.Fatalf("marshal error: %v", err)
+	}
+
+	var unmarshaled map[string]any
+	if err := json.Unmarshal(data, &unmarshaled); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	if unmarshaled["title"] != "New Task" {
+		t.Errorf("expected title='New Task', got %v", unmarshaled["title"])
+	}
+	if unmarshaled["project_id"].(float64) != 1 {
+		t.Errorf("expected project_id=1, got %v", unmarshaled["project_id"])
+	}
+	tags := unmarshaled["tags"].([]any)
+	if len(tags) != 2 {
+		t.Errorf("expected 2 tags, got %d", len(tags))
+	}
+}
+
+func TestCreateTaskRequest_OmitEmpty(t *testing.T) {
+	req := CreateTaskRequest{
+		Title:     "Minimal Task",
+		ProjectID: 1,
+	}
+
+	data, err := json.Marshal(req)
+	if err != nil {
+		t.Fatalf("marshal error: %v", err)
+	}
+
+	var unmarshaled map[string]any
+	if err := json.Unmarshal(data, &unmarshaled); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	// Should not have omitempty fields
+	if _, exists := unmarshaled["description"]; exists {
+		t.Error("description should be omitted when empty")
+	}
+	if _, exists := unmarshaled["color_id"]; exists {
+		t.Error("color_id should be omitted when empty")
+	}
+}
+
+func TestUpdateTaskRequest_MarshalJSON(t *testing.T) {
+	title := "Updated Title"
+	priority := 5
+
+	req := UpdateTaskRequest{
+		ID:       42,
+		Title:    &title,
+		Priority: &priority,
+	}
+
+	data, err := json.Marshal(req)
+	if err != nil {
+		t.Fatalf("marshal error: %v", err)
+	}
+
+	var unmarshaled map[string]any
+	if err := json.Unmarshal(data, &unmarshaled); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	if unmarshaled["id"].(float64) != 42 {
+		t.Errorf("expected id=42, got %v", unmarshaled["id"])
+	}
+	if unmarshaled["title"] != "Updated Title" {
+		t.Errorf("expected title='Updated Title', got %v", unmarshaled["title"])
+	}
+	if unmarshaled["priority"].(float64) != 5 {
+		t.Errorf("expected priority=5, got %v", unmarshaled["priority"])
+	}
+
+	// Should not have fields that weren't set
+	if _, exists := unmarshaled["description"]; exists {
+		t.Error("description should be omitted when nil")
+	}
+}
+
+func TestUpdateTaskRequest_ZeroValueVsNil(t *testing.T) {
+	// Test that we can distinguish between "not set" and "set to zero"
+	zero := 0
+	emptyString := ""
+
+	req := UpdateTaskRequest{
+		ID:       42,
+		Priority: &zero,        // Explicitly set to 0
+		ColorID:  &emptyString, // Explicitly set to empty string
+	}
+
+	data, err := json.Marshal(req)
+	if err != nil {
+		t.Fatalf("marshal error: %v", err)
+	}
+
+	var unmarshaled map[string]any
+	if err := json.Unmarshal(data, &unmarshaled); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	// These should be present even though they're zero values
+	if _, exists := unmarshaled["priority"]; !exists {
+		t.Error("priority should be present when explicitly set to 0")
+	}
+	if _, exists := unmarshaled["color_id"]; !exists {
+		t.Error("color_id should be present when explicitly set to empty string")
+	}
+}
+
+func TestTask_TimestampFields(t *testing.T) {
+	jsonData := `{
+		"id": "1",
+		"title": "Test",
+		"description": "",
+		"date_creation": 1609459200,
+		"date_modification": 1609545600,
+		"date_completed": 0,
+		"date_due": 1610064000,
+		"color_id": "blue",
+		"project_id": "1",
+		"column_id": "1",
+		"owner_id": "0",
+		"creator_id": "1",
+		"position": "1",
+		"is_active": "1",
+		"score": "0",
+		"category_id": "0",
+		"swimlane_id": "0",
+		"priority": "0",
+		"reference": "",
+		"recurrence_status": "0",
+		"recurrence_trigger": "0",
+		"recurrence_factor": "0",
+		"recurrence_timeframe": "0",
+		"recurrence_basedate": "0",
+		"recurrence_parent": "0",
+		"recurrence_child": "0"
+	}`
+
+	var task Task
+	if err := json.Unmarshal([]byte(jsonData), &task); err != nil {
+		t.Fatalf("unmarshal error: %v", err)
+	}
+
+	// Check that creation date is parsed correctly
+	expectedCreation := time.Unix(1609459200, 0)
+	if !task.DateCreation.Time.Equal(expectedCreation) {
+		t.Errorf("expected DateCreation=%v, got %v", expectedCreation, task.DateCreation.Time)
+	}
+
+	// Check that completed date is zero
+	if !task.DateCompleted.IsZero() {
+		t.Error("expected DateCompleted to be zero")
+	}
+
+	// Check that due date is parsed
+	if task.DateDue.IsZero() {
+		t.Error("expected DateDue to be set")
+	}
+}