package github

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"strings"

	ghErrors "github.com/github/github-mcp-server/pkg/errors"
	"github.com/github/github-mcp-server/pkg/translations"
	"github.com/google/go-github/v79/github"
	"github.com/mark3labs/mcp-go/mcp"
	"github.com/mark3labs/mcp-go/server"
)

const (
	ProjectUpdateFailedError = "failed to update a project item"
	ProjectAddFailedError    = "failed to add a project item"
	ProjectDeleteFailedError = "failed to delete a project item"
	ProjectListFailedError   = "failed to list project items"
	MaxProjectsPerPage       = 50
)

// FlexibleString handles JSON unmarshaling of fields that can be either
// a plain string or an object with "raw" and "html" fields.
// This is needed because the GitHub API returns option names as strings,
// while go-github v79 expects them to be ProjectV2TextContent objects.
type FlexibleString struct {
	Raw  string `json:"raw,omitempty"`
	HTML string `json:"html,omitempty"`
}

// UnmarshalJSON implements custom unmarshaling for FlexibleString
func (f *FlexibleString) UnmarshalJSON(data []byte) error {
	// Try to unmarshal as a plain string first
	var s string
	if err := json.Unmarshal(data, &s); err == nil {
		f.Raw = s
		f.HTML = s
		return nil
	}

	// If that fails, try to unmarshal as an object
	type flexibleStringAlias FlexibleString
	var obj flexibleStringAlias
	if err := json.Unmarshal(data, &obj); err != nil {
		return err
	}
	*f = FlexibleString(obj)
	return nil
}

// ProjectFieldOption represents an option for single_select or iteration fields.
// This is a custom type that handles the flexible name format from the GitHub API.
type ProjectFieldOption struct {
	ID          string          `json:"id,omitempty"`
	Name        *FlexibleString `json:"name,omitempty"`
	Color       string          `json:"color,omitempty"`
	Description *FlexibleString `json:"description,omitempty"`
}

// ProjectFieldIteration represents an iteration within a project field.
type ProjectFieldIteration struct {
	ID        string          `json:"id,omitempty"`
	Title     *FlexibleString `json:"title,omitempty"`
	StartDate string          `json:"start_date,omitempty"`
	Duration  int             `json:"duration,omitempty"`
}

// ProjectFieldConfiguration represents the configuration for iteration fields.
type ProjectFieldConfiguration struct {
	Duration   int                      `json:"duration,omitempty"`
	StartDay   int                      `json:"start_day,omitempty"`
	Iterations []*ProjectFieldIteration `json:"iterations,omitempty"`
}

// ProjectField represents a field in a GitHub Project V2.
// This is a custom type that properly handles the options array format from the GitHub API.
type ProjectField struct {
	ID            int64                      `json:"id,omitempty"`
	NodeID        string                     `json:"node_id,omitempty"`
	Name          string                     `json:"name,omitempty"`
	DataType      string                     `json:"data_type,omitempty"`
	ProjectURL    string                     `json:"project_url,omitempty"`
	Options       []*ProjectFieldOption      `json:"options,omitempty"`
	Configuration *ProjectFieldConfiguration `json:"configuration,omitempty"`
	CreatedAt     string                     `json:"created_at,omitempty"`
	UpdatedAt     string                     `json:"updated_at,omitempty"`
}

func ListProjects(getClient GetClientFn, t translations.TranslationHelperFunc) (tool mcp.Tool, handler server.ToolHandlerFunc) {
	return mcp.NewTool("list_projects",
			mcp.WithDescription(t("TOOL_LIST_PROJECTS_DESCRIPTION", `List Projects for a user or organization`)),
			mcp.WithToolAnnotation(mcp.ToolAnnotation{
				Title:        t("TOOL_LIST_PROJECTS_USER_TITLE", "List projects"),
				ReadOnlyHint: ToBoolPtr(true),
			}),
			mcp.WithString("owner_type",
				mcp.Required(), mcp.Description("Owner type"), mcp.Enum("user", "org"),
			),
			mcp.WithString("owner",
				mcp.Required(),
				mcp.Description("If owner_type == user it is the handle for the GitHub user account. If owner_type == org it is the name of the organization. The name is not case sensitive."),
			),
			mcp.WithString("query",
				mcp.Description(`Filter projects by title text and open/closed state; permitted qualifiers: is:open, is:closed; examples: "roadmap is:open", "is:open feature planning".`),
			),
			mcp.WithNumber("per_page",
				mcp.Description(fmt.Sprintf("Results per page (max %d)", MaxProjectsPerPage)),
			),
			mcp.WithString("after",
				mcp.Description("Forward pagination cursor from previous pageInfo.nextCursor."),
			),
			mcp.WithString("before",
				mcp.Description("Backward pagination cursor from previous pageInfo.prevCursor (rare)."),
			),
		), func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
			owner, err := RequiredParam[string](req, "owner")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			ownerType, err := RequiredParam[string](req, "owner_type")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			queryStr, err := OptionalParam[string](req, "query")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			pagination, err := extractPaginationOptions(req)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			client, err := getClient(ctx)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			var resp *github.Response
			var projects []*github.ProjectV2
			var queryPtr *string

			if queryStr != "" {
				queryPtr = &queryStr
			}

			minimalProjects := []MinimalProject{}
			opts := &github.ListProjectsOptions{
				ListProjectsPaginationOptions: pagination,
				Query:                         queryPtr,
			}

			if ownerType == "org" {
				projects, resp, err = client.Projects.ListOrganizationProjects(ctx, owner, opts)
			} else {
				projects, resp, err = client.Projects.ListUserProjects(ctx, owner, opts)
			}

			if err != nil {
				return ghErrors.NewGitHubAPIErrorResponse(ctx,
					"failed to list projects",
					resp,
					err,
				), nil
			}
			defer func() { _ = resp.Body.Close() }()

			for _, project := range projects {
				minimalProjects = append(minimalProjects, *convertToMinimalProject(project))
			}

			response := map[string]any{
				"projects": minimalProjects,
				"pageInfo": buildPageInfo(resp),
			}

			r, err := json.Marshal(response)
			if err != nil {
				return nil, fmt.Errorf("failed to marshal response: %w", err)
			}

			return mcp.NewToolResultText(string(r)), nil
		}
}

func GetProject(getClient GetClientFn, t translations.TranslationHelperFunc) (tool mcp.Tool, handler server.ToolHandlerFunc) {
	return mcp.NewTool("get_project",
			mcp.WithDescription(t("TOOL_GET_PROJECT_DESCRIPTION", "Get Project for a user or org")),
			mcp.WithToolAnnotation(mcp.ToolAnnotation{
				Title:        t("TOOL_GET_PROJECT_USER_TITLE", "Get project"),
				ReadOnlyHint: ToBoolPtr(true),
			}),
			mcp.WithNumber("project_number",
				mcp.Required(),
				mcp.Description("The project's number"),
			),
			mcp.WithString("owner_type",
				mcp.Required(),
				mcp.Description("Owner type"),
				mcp.Enum("user", "org"),
			),
			mcp.WithString("owner",
				mcp.Required(),
				mcp.Description("If owner_type == user it is the handle for the GitHub user account. If owner_type == org it is the name of the organization. The name is not case sensitive."),
			),
		), func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {

			projectNumber, err := RequiredInt(req, "project_number")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			owner, err := RequiredParam[string](req, "owner")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			ownerType, err := RequiredParam[string](req, "owner_type")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			client, err := getClient(ctx)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			var resp *github.Response
			var project *github.ProjectV2

			if ownerType == "org" {
				project, resp, err = client.Projects.GetOrganizationProject(ctx, owner, projectNumber)
			} else {
				project, resp, err = client.Projects.GetUserProject(ctx, owner, projectNumber)
			}
			if err != nil {
				return ghErrors.NewGitHubAPIErrorResponse(ctx,
					"failed to get project",
					resp,
					err,
				), nil
			}
			defer func() { _ = resp.Body.Close() }()

			if resp.StatusCode != http.StatusOK {
				body, err := io.ReadAll(resp.Body)
				if err != nil {
					return nil, fmt.Errorf("failed to read response body: %w", err)
				}
				return mcp.NewToolResultError(fmt.Sprintf("failed to get project: %s", string(body))), nil
			}

			minimalProject := convertToMinimalProject(project)
			r, err := json.Marshal(minimalProject)
			if err != nil {
				return nil, fmt.Errorf("failed to marshal response: %w", err)
			}

			return mcp.NewToolResultText(string(r)), nil
		}
}

func ListProjectFields(getClient GetClientFn, t translations.TranslationHelperFunc) (tool mcp.Tool, handler server.ToolHandlerFunc) {
	return mcp.NewTool("list_project_fields",
			mcp.WithDescription(t("TOOL_LIST_PROJECT_FIELDS_DESCRIPTION", "List Project fields for a user or org")),
			mcp.WithToolAnnotation(mcp.ToolAnnotation{
				Title:        t("TOOL_LIST_PROJECT_FIELDS_USER_TITLE", "List project fields"),
				ReadOnlyHint: ToBoolPtr(true),
			}),
			mcp.WithString("owner_type",
				mcp.Required(),
				mcp.Description("Owner type"),
				mcp.Enum("user", "org")),
			mcp.WithString("owner",
				mcp.Required(),
				mcp.Description("If owner_type == user it is the handle for the GitHub user account. If owner_type == org it is the name of the organization. The name is not case sensitive."),
			),
			mcp.WithNumber("project_number",
				mcp.Required(),
				mcp.Description("The project's number."),
			),
			mcp.WithNumber("per_page",
				mcp.Description(fmt.Sprintf("Results per page (max %d)", MaxProjectsPerPage)),
			),
			mcp.WithString("after",
				mcp.Description("Forward pagination cursor from previous pageInfo.nextCursor."),
			),
			mcp.WithString("before",
				mcp.Description("Backward pagination cursor from previous pageInfo.prevCursor (rare)."),
			),
		), func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
			owner, err := RequiredParam[string](req, "owner")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			ownerType, err := RequiredParam[string](req, "owner_type")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			projectNumber, err := RequiredInt(req, "project_number")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			pagination, err := extractPaginationOptions(req)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			client, err := getClient(ctx)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			// Build the URL for the API request
			var urlPath string
			if ownerType == "org" {
				urlPath = fmt.Sprintf("orgs/%s/projectsV2/%d/fields", owner, projectNumber)
			} else {
				urlPath = fmt.Sprintf("users/%s/projectsV2/%d/fields", owner, projectNumber)
			}

			// Create options for the request
			opts := &github.ListProjectsOptions{
				ListProjectsPaginationOptions: pagination,
			}

			// Make the raw API request using go-github's client
			// We use our custom ProjectField type which handles flexible name format
			projectFields, resp, err := listProjectFieldsRaw(ctx, client, urlPath, opts)
			if err != nil {
				return ghErrors.NewGitHubAPIErrorResponse(ctx,
					"failed to list project fields",
					resp,
					err,
				), nil
			}
			defer func() { _ = resp.Body.Close() }()

			response := map[string]any{
				"fields":   projectFields,
				"pageInfo": buildPageInfo(resp),
			}

			r, err := json.Marshal(response)
			if err != nil {
				return nil, fmt.Errorf("failed to marshal response: %w", err)
			}

			return mcp.NewToolResultText(string(r)), nil
		}
}

// listProjectFieldsRaw makes a raw API request to list project fields and parses
// the response using our custom ProjectField type that handles flexible name formats.
func listProjectFieldsRaw(ctx context.Context, client *github.Client, urlPath string, opts *github.ListProjectsOptions) ([]*ProjectField, *github.Response, error) {
	u, err := addProjectOptions(urlPath, opts)
	if err != nil {
		return nil, nil, err
	}

	req, err := client.NewRequest("GET", u, nil)
	if err != nil {
		return nil, nil, err
	}

	var fields []*ProjectField
	resp, err := client.Do(ctx, req, &fields)
	if err != nil {
		return nil, resp, err
	}
	return fields, resp, nil
}

// addProjectOptions adds query parameters to a URL for project API requests.
func addProjectOptions(s string, opts *github.ListProjectsOptions) (string, error) {
	if opts == nil {
		return s, nil
	}

	// Build query parameters manually
	params := make([]string, 0)
	if opts.PerPage != nil && *opts.PerPage > 0 {
		params = append(params, fmt.Sprintf("per_page=%d", *opts.PerPage))
	}
	if opts.After != nil && *opts.After != "" {
		params = append(params, fmt.Sprintf("after=%s", *opts.After))
	}
	if opts.Before != nil && *opts.Before != "" {
		params = append(params, fmt.Sprintf("before=%s", *opts.Before))
	}
	if opts.Query != nil && *opts.Query != "" {
		params = append(params, fmt.Sprintf("q=%s", *opts.Query))
	}

	if len(params) > 0 {
		s = s + "?" + strings.Join(params, "&")
	}
	return s, nil
}

// getProjectFieldRaw makes a raw API request to get a single project field and parses
// the response using our custom ProjectField type that handles flexible name formats.
func getProjectFieldRaw(ctx context.Context, client *github.Client, urlPath string) (*ProjectField, *github.Response, error) {
	req, err := client.NewRequest("GET", urlPath, nil)
	if err != nil {
		return nil, nil, err
	}

	var field ProjectField
	resp, err := client.Do(ctx, req, &field)
	if err != nil {
		return nil, resp, err
	}
	return &field, resp, nil
}

func GetProjectField(getClient GetClientFn, t translations.TranslationHelperFunc) (tool mcp.Tool, handler server.ToolHandlerFunc) {
	return mcp.NewTool("get_project_field",
			mcp.WithDescription(t("TOOL_GET_PROJECT_FIELD_DESCRIPTION", "Get Project field for a user or org")),
			mcp.WithToolAnnotation(mcp.ToolAnnotation{
				Title:        t("TOOL_GET_PROJECT_FIELD_USER_TITLE", "Get project field"),
				ReadOnlyHint: ToBoolPtr(true),
			}),
			mcp.WithString("owner_type",
				mcp.Required(),
				mcp.Description("Owner type"), mcp.Enum("user", "org")),
			mcp.WithString("owner",
				mcp.Required(),
				mcp.Description("If owner_type == user it is the handle for the GitHub user account. If owner_type == org it is the name of the organization. The name is not case sensitive."),
			),
			mcp.WithNumber("project_number",
				mcp.Required(),
				mcp.Description("The project's number.")),
			mcp.WithNumber("field_id",
				mcp.Required(),
				mcp.Description("The field's id."),
			),
		), func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
			owner, err := RequiredParam[string](req, "owner")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			ownerType, err := RequiredParam[string](req, "owner_type")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			projectNumber, err := RequiredInt(req, "project_number")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			fieldID, err := RequiredBigInt(req, "field_id")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			client, err := getClient(ctx)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			// Build the URL for the API request
			var urlPath string
			if ownerType == "org" {
				urlPath = fmt.Sprintf("orgs/%s/projectsV2/%d/fields/%d", owner, projectNumber, fieldID)
			} else {
				urlPath = fmt.Sprintf("users/%s/projectsV2/%d/fields/%d", owner, projectNumber, fieldID)
			}

			// Make the raw API request using go-github's client
			// We use our custom ProjectField type which handles flexible name format
			projectField, resp, err := getProjectFieldRaw(ctx, client, urlPath)
			if err != nil {
				return ghErrors.NewGitHubAPIErrorResponse(ctx,
					"failed to get project field",
					resp,
					err,
				), nil
			}
			defer func() { _ = resp.Body.Close() }()

			if resp.StatusCode != http.StatusOK {
				body, err := io.ReadAll(resp.Body)
				if err != nil {
					return nil, fmt.Errorf("failed to read response body: %w", err)
				}
				return mcp.NewToolResultError(fmt.Sprintf("failed to get project field: %s", string(body))), nil
			}
			r, err := json.Marshal(projectField)
			if err != nil {
				return nil, fmt.Errorf("failed to marshal response: %w", err)
			}

			return mcp.NewToolResultText(string(r)), nil
		}
}

func ListProjectItems(getClient GetClientFn, t translations.TranslationHelperFunc) (tool mcp.Tool, handler server.ToolHandlerFunc) {
	return mcp.NewTool("list_project_items",
			mcp.WithDescription(t("TOOL_LIST_PROJECT_ITEMS_DESCRIPTION", `Search project items with advanced filtering`)),
			mcp.WithToolAnnotation(mcp.ToolAnnotation{
				Title:        t("TOOL_LIST_PROJECT_ITEMS_USER_TITLE", "List project items"),
				ReadOnlyHint: ToBoolPtr(true),
			}),
			mcp.WithString("owner_type",
				mcp.Required(),
				mcp.Description("Owner type"),
				mcp.Enum("user", "org"),
			),
			mcp.WithString("owner",
				mcp.Required(),
				mcp.Description("If owner_type == user it is the handle for the GitHub user account. If owner_type == org it is the name of the organization. The name is not case sensitive."),
			),
			mcp.WithNumber("project_number", mcp.Required(),
				mcp.Description("The project's number."),
			),
			mcp.WithString("query",
				mcp.Description(`Query string for advanced filtering of project items using GitHub's project filtering syntax.`),
			),
			mcp.WithNumber("per_page",
				mcp.Description(fmt.Sprintf("Results per page (max %d)", MaxProjectsPerPage)),
			),
			mcp.WithString("after",
				mcp.Description("Forward pagination cursor from previous pageInfo.nextCursor."),
			),
			mcp.WithString("before",
				mcp.Description("Backward pagination cursor from previous pageInfo.prevCursor (rare)."),
			),
			mcp.WithArray("fields",
				mcp.Description("Field IDs to include (e.g. [\"102589\", \"985201\"]). CRITICAL: Always provide to get field values. Without this, only titles returned."),
				mcp.WithStringItems(),
			),
		), func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
			owner, err := RequiredParam[string](req, "owner")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			ownerType, err := RequiredParam[string](req, "owner_type")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			projectNumber, err := RequiredInt(req, "project_number")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			queryStr, err := OptionalParam[string](req, "query")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			fields, err := OptionalBigIntArrayParam(req, "fields")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			pagination, err := extractPaginationOptions(req)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			client, err := getClient(ctx)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			var resp *github.Response
			var projectItems []*github.ProjectV2Item
			var queryPtr *string

			if queryStr != "" {
				queryPtr = &queryStr
			}

			opts := &github.ListProjectItemsOptions{
				Fields: fields,
				ListProjectsOptions: github.ListProjectsOptions{
					ListProjectsPaginationOptions: pagination,
					Query:                         queryPtr,
				},
			}

			if ownerType == "org" {
				projectItems, resp, err = client.Projects.ListOrganizationProjectItems(ctx, owner, projectNumber, opts)
			} else {
				projectItems, resp, err = client.Projects.ListUserProjectItems(ctx, owner, projectNumber, opts)
			}

			if err != nil {
				return ghErrors.NewGitHubAPIErrorResponse(ctx,
					ProjectListFailedError,
					resp,
					err,
				), nil
			}
			defer func() { _ = resp.Body.Close() }()

			response := map[string]any{
				"items":    projectItems,
				"pageInfo": buildPageInfo(resp),
			}

			r, err := json.Marshal(response)
			if err != nil {
				return nil, fmt.Errorf("failed to marshal response: %w", err)
			}

			return mcp.NewToolResultText(string(r)), nil
		}
}

func GetProjectItem(getClient GetClientFn, t translations.TranslationHelperFunc) (tool mcp.Tool, handler server.ToolHandlerFunc) {
	return mcp.NewTool("get_project_item",
			mcp.WithDescription(t("TOOL_GET_PROJECT_ITEM_DESCRIPTION", "Get a specific Project item for a user or org")),
			mcp.WithToolAnnotation(mcp.ToolAnnotation{
				Title:        t("TOOL_GET_PROJECT_ITEM_USER_TITLE", "Get project item"),
				ReadOnlyHint: ToBoolPtr(true),
			}),
			mcp.WithString("owner_type",
				mcp.Required(),
				mcp.Description("Owner type"),
				mcp.Enum("user", "org"),
			),
			mcp.WithString("owner",
				mcp.Required(),
				mcp.Description("If owner_type == user it is the handle for the GitHub user account. If owner_type == org it is the name of the organization. The name is not case sensitive."),
			),
			mcp.WithNumber("project_number",
				mcp.Required(),
				mcp.Description("The project's number."),
			),
			mcp.WithNumber("item_id",
				mcp.Required(),
				mcp.Description("The item's ID."),
			),
			mcp.WithArray("fields",
				mcp.Description("Specific list of field IDs to include in the response (e.g. [\"102589\", \"985201\", \"169875\"]). If not provided, only the title field is included."),
				mcp.WithStringItems(),
			),
		), func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
			owner, err := RequiredParam[string](req, "owner")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			ownerType, err := RequiredParam[string](req, "owner_type")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			projectNumber, err := RequiredInt(req, "project_number")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			itemID, err := RequiredBigInt(req, "item_id")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			fields, err := OptionalBigIntArrayParam(req, "fields")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			client, err := getClient(ctx)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			var resp *github.Response
			var projectItem *github.ProjectV2Item
			var opts *github.GetProjectItemOptions

			if len(fields) > 0 {
				opts = &github.GetProjectItemOptions{
					Fields: fields,
				}
			}

			if ownerType == "org" {
				projectItem, resp, err = client.Projects.GetOrganizationProjectItem(ctx, owner, projectNumber, itemID, opts)
			} else {
				projectItem, resp, err = client.Projects.GetUserProjectItem(ctx, owner, projectNumber, itemID, opts)
			}

			if err != nil {
				return ghErrors.NewGitHubAPIErrorResponse(ctx,
					"failed to get project item",
					resp,
					err,
				), nil
			}
			defer func() { _ = resp.Body.Close() }()

			r, err := json.Marshal(projectItem)
			if err != nil {
				return nil, fmt.Errorf("failed to marshal response: %w", err)
			}

			return mcp.NewToolResultText(string(r)), nil
		}
}

func AddProjectItem(getClient GetClientFn, t translations.TranslationHelperFunc) (tool mcp.Tool, handler server.ToolHandlerFunc) {
	return mcp.NewTool("add_project_item",
			mcp.WithDescription(t("TOOL_ADD_PROJECT_ITEM_DESCRIPTION", "Add a specific Project item for a user or org")),
			mcp.WithToolAnnotation(mcp.ToolAnnotation{
				Title:        t("TOOL_ADD_PROJECT_ITEM_USER_TITLE", "Add project item"),
				ReadOnlyHint: ToBoolPtr(false),
			}),
			mcp.WithString("owner_type",
				mcp.Required(),
				mcp.Description("Owner type"), mcp.Enum("user", "org"),
			),
			mcp.WithString("owner",
				mcp.Required(),
				mcp.Description("If owner_type == user it is the handle for the GitHub user account. If owner_type == org it is the name of the organization. The name is not case sensitive."),
			),
			mcp.WithNumber("project_number",
				mcp.Required(),
				mcp.Description("The project's number."),
			),
			mcp.WithString("item_type",
				mcp.Required(),
				mcp.Description("The item's type, either issue or pull_request."),
				mcp.Enum("issue", "pull_request"),
			),
			mcp.WithNumber("item_id",
				mcp.Required(),
				mcp.Description("The numeric ID of the issue or pull request to add to the project."),
			),
		), func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
			owner, err := RequiredParam[string](req, "owner")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			ownerType, err := RequiredParam[string](req, "owner_type")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			projectNumber, err := RequiredInt(req, "project_number")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			itemID, err := RequiredBigInt(req, "item_id")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			itemType, err := RequiredParam[string](req, "item_type")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			if itemType != "issue" && itemType != "pull_request" {
				return mcp.NewToolResultError("item_type must be either 'issue' or 'pull_request'"), nil
			}

			client, err := getClient(ctx)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			newItem := &github.AddProjectItemOptions{
				ID:   itemID,
				Type: toNewProjectType(itemType),
			}

			var resp *github.Response
			var addedItem *github.ProjectV2Item

			if ownerType == "org" {
				addedItem, resp, err = client.Projects.AddOrganizationProjectItem(ctx, owner, projectNumber, newItem)
			} else {
				addedItem, resp, err = client.Projects.AddUserProjectItem(ctx, owner, projectNumber, newItem)
			}

			if err != nil {
				return ghErrors.NewGitHubAPIErrorResponse(ctx,
					ProjectAddFailedError,
					resp,
					err,
				), nil
			}
			defer func() { _ = resp.Body.Close() }()

			if resp.StatusCode != http.StatusCreated {
				body, err := io.ReadAll(resp.Body)
				if err != nil {
					return nil, fmt.Errorf("failed to read response body: %w", err)
				}
				return mcp.NewToolResultError(fmt.Sprintf("%s: %s", ProjectAddFailedError, string(body))), nil
			}
			r, err := json.Marshal(addedItem)
			if err != nil {
				return nil, fmt.Errorf("failed to marshal response: %w", err)
			}

			return mcp.NewToolResultText(string(r)), nil
		}
}

func UpdateProjectItem(getClient GetClientFn, t translations.TranslationHelperFunc) (tool mcp.Tool, handler server.ToolHandlerFunc) {
	return mcp.NewTool("update_project_item",
			mcp.WithDescription(t("TOOL_UPDATE_PROJECT_ITEM_DESCRIPTION", "Update a specific Project item for a user or org")),
			mcp.WithToolAnnotation(mcp.ToolAnnotation{
				Title:        t("TOOL_UPDATE_PROJECT_ITEM_USER_TITLE", "Update project item"),
				ReadOnlyHint: ToBoolPtr(false),
			}),
			mcp.WithString("owner_type",
				mcp.Required(), mcp.Description("Owner type"),
				mcp.Enum("user", "org"),
			),
			mcp.WithString("owner",
				mcp.Required(),
				mcp.Description("If owner_type == user it is the handle for the GitHub user account. If owner_type == org it is the name of the organization. The name is not case sensitive."),
			),
			mcp.WithNumber("project_number",
				mcp.Required(),
				mcp.Description("The project's number."),
			),
			mcp.WithNumber("item_id",
				mcp.Required(),
				mcp.Description("The unique identifier of the project item. This is not the issue or pull request ID."),
			),
			mcp.WithObject("updated_field",
				mcp.Required(),
				mcp.Description("Object consisting of the ID of the project field to update and the new value for the field. To clear the field, set value to null. Example: {\"id\": 123456, \"value\": \"New Value\"}"),
			),
		), func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
			owner, err := RequiredParam[string](req, "owner")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			ownerType, err := RequiredParam[string](req, "owner_type")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			projectNumber, err := RequiredInt(req, "project_number")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			itemID, err := RequiredBigInt(req, "item_id")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			rawUpdatedField, exists := req.GetArguments()["updated_field"]
			if !exists {
				return mcp.NewToolResultError("missing required parameter: updated_field"), nil
			}

			fieldValue, ok := rawUpdatedField.(map[string]any)
			if !ok || fieldValue == nil {
				return mcp.NewToolResultError("field_value must be an object"), nil
			}

			updatePayload, err := buildUpdateProjectItem(fieldValue)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			client, err := getClient(ctx)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			var resp *github.Response
			var updatedItem *github.ProjectV2Item

			if ownerType == "org" {
				updatedItem, resp, err = client.Projects.UpdateOrganizationProjectItem(ctx, owner, projectNumber, itemID, updatePayload)
			} else {
				updatedItem, resp, err = client.Projects.UpdateUserProjectItem(ctx, owner, projectNumber, itemID, updatePayload)
			}

			if err != nil {
				return ghErrors.NewGitHubAPIErrorResponse(ctx,
					ProjectUpdateFailedError,
					resp,
					err,
				), nil
			}
			defer func() { _ = resp.Body.Close() }()

			if resp.StatusCode != http.StatusOK {
				body, err := io.ReadAll(resp.Body)
				if err != nil {
					return nil, fmt.Errorf("failed to read response body: %w", err)
				}
				return mcp.NewToolResultError(fmt.Sprintf("%s: %s", ProjectUpdateFailedError, string(body))), nil
			}
			r, err := json.Marshal(updatedItem)
			if err != nil {
				return nil, fmt.Errorf("failed to marshal response: %w", err)
			}

			return mcp.NewToolResultText(string(r)), nil
		}
}

func DeleteProjectItem(getClient GetClientFn, t translations.TranslationHelperFunc) (tool mcp.Tool, handler server.ToolHandlerFunc) {
	return mcp.NewTool("delete_project_item",
			mcp.WithDescription(t("TOOL_DELETE_PROJECT_ITEM_DESCRIPTION", "Delete a specific Project item for a user or org")),
			mcp.WithToolAnnotation(mcp.ToolAnnotation{
				Title:        t("TOOL_DELETE_PROJECT_ITEM_USER_TITLE", "Delete project item"),
				ReadOnlyHint: ToBoolPtr(false),
			}),
			mcp.WithString("owner_type",
				mcp.Required(),
				mcp.Description("Owner type"),
				mcp.Enum("user", "org"),
			),
			mcp.WithString("owner",
				mcp.Required(),
				mcp.Description("If owner_type == user it is the handle for the GitHub user account. If owner_type == org it is the name of the organization. The name is not case sensitive."),
			),
			mcp.WithNumber("project_number",
				mcp.Required(),
				mcp.Description("The project's number."),
			),
			mcp.WithNumber("item_id",
				mcp.Required(),
				mcp.Description("The internal project item ID to delete from the project (not the issue or pull request ID)."),
			),
		), func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
			owner, err := RequiredParam[string](req, "owner")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			ownerType, err := RequiredParam[string](req, "owner_type")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			projectNumber, err := RequiredInt(req, "project_number")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			itemID, err := RequiredBigInt(req, "item_id")
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}
			client, err := getClient(ctx)
			if err != nil {
				return mcp.NewToolResultError(err.Error()), nil
			}

			var resp *github.Response
			if ownerType == "org" {
				resp, err = client.Projects.DeleteOrganizationProjectItem(ctx, owner, projectNumber, itemID)
			} else {
				resp, err = client.Projects.DeleteUserProjectItem(ctx, owner, projectNumber, itemID)
			}

			if err != nil {
				return ghErrors.NewGitHubAPIErrorResponse(ctx,
					ProjectDeleteFailedError,
					resp,
					err,
				), nil
			}
			defer func() { _ = resp.Body.Close() }()

			if resp.StatusCode != http.StatusNoContent {
				body, err := io.ReadAll(resp.Body)
				if err != nil {
					return nil, fmt.Errorf("failed to read response body: %w", err)
				}
				return mcp.NewToolResultError(fmt.Sprintf("%s: %s", ProjectDeleteFailedError, string(body))), nil
			}
			return mcp.NewToolResultText("project item successfully deleted"), nil
		}
}

type pageInfo struct {
	HasNextPage     bool   `json:"hasNextPage"`
	HasPreviousPage bool   `json:"hasPreviousPage"`
	NextCursor      string `json:"nextCursor,omitempty"`
	PrevCursor      string `json:"prevCursor,omitempty"`
}

func toNewProjectType(projType string) string {
	switch strings.ToLower(projType) {
	case "issue":
		return "Issue"
	case "pull_request":
		return "PullRequest"
	default:
		return ""
	}
}

// validateAndConvertToInt64 ensures the value is a number and converts it to int64.
func validateAndConvertToInt64(value any) (int64, error) {
	switch v := value.(type) {
	case float64:
		// Validate that the float64 can be safely converted to int64
		intVal := int64(v)
		if float64(intVal) != v {
			return 0, fmt.Errorf("value must be a valid integer (got %v)", v)
		}
		return intVal, nil
	case int64:
		return v, nil
	case int:
		return int64(v), nil
	default:
		return 0, fmt.Errorf("value must be a number (got %T)", v)
	}
}

// buildUpdateProjectItem constructs UpdateProjectItemOptions from the input map.
func buildUpdateProjectItem(input map[string]any) (*github.UpdateProjectItemOptions, error) {
	if input == nil {
		return nil, fmt.Errorf("updated_field must be an object")
	}

	idField, ok := input["id"]
	if !ok {
		return nil, fmt.Errorf("updated_field.id is required")
	}

	fieldID, err := validateAndConvertToInt64(idField)
	if err != nil {
		return nil, fmt.Errorf("updated_field.id: %w", err)
	}

	valueField, ok := input["value"]
	if !ok {
		return nil, fmt.Errorf("updated_field.value is required")
	}

	payload := &github.UpdateProjectItemOptions{
		Fields: []*github.UpdateProjectV2Field{{
			ID:    fieldID,
			Value: valueField,
		}},
	}

	return payload, nil
}

func buildPageInfo(resp *github.Response) pageInfo {
	return pageInfo{
		HasNextPage:     resp.After != "",
		HasPreviousPage: resp.Before != "",
		NextCursor:      resp.After,
		PrevCursor:      resp.Before,
	}
}

func extractPaginationOptions(request mcp.CallToolRequest) (github.ListProjectsPaginationOptions, error) {
	perPage, err := OptionalIntParamWithDefault(request, "per_page", MaxProjectsPerPage)
	if err != nil {
		return github.ListProjectsPaginationOptions{}, err
	}
	if perPage > MaxProjectsPerPage {
		perPage = MaxProjectsPerPage
	}

	after, err := OptionalParam[string](request, "after")
	if err != nil {
		return github.ListProjectsPaginationOptions{}, err
	}

	before, err := OptionalParam[string](request, "before")
	if err != nil {
		return github.ListProjectsPaginationOptions{}, err
	}

	opts := github.ListProjectsPaginationOptions{
		PerPage: &perPage,
	}

	// Only set After/Before if they have non-empty values
	if after != "" {
		opts.After = &after
	}

	if before != "" {
		opts.Before = &before
	}

	return opts, nil
}