package github

import (
	"context"
	"fmt"
	"strings"

	"github.com/github/github-mcp-server/pkg/raw"
	"github.com/github/github-mcp-server/pkg/toolsets"
	"github.com/github/github-mcp-server/pkg/translations"
	"github.com/google/go-github/v74/github"
	"github.com/mark3labs/mcp-go/server"
	"github.com/shurcooL/githubv4"
)

type GetClientFn func(context.Context) (*github.Client, error)
type GetGQLClientFn func(context.Context) (*githubv4.Client, error)

// ToolsetMetadata holds metadata for a toolset including its ID and description
type ToolsetMetadata struct {
	ID          string
	Description string
}

var (
	ToolsetMetadataContext = ToolsetMetadata{
		ID:          "context",
		Description: "Tools that provide context about the current user and GitHub context you are operating in",
	}
	ToolsetMetadataRepos = ToolsetMetadata{
		ID:          "repos",
		Description: "GitHub Repository related tools",
	}
	ToolsetMetadataIssues = ToolsetMetadata{
		ID:          "issues",
		Description: "GitHub Issues related tools",
	}
	ToolsetMetadataPullRequests = ToolsetMetadata{
		ID:          "pull_requests",
		Description: "GitHub Pull Request related tools",
	}
	ToolsetMetadataUsers = ToolsetMetadata{
		ID:          "users",
		Description: "GitHub User related tools",
	}
	ToolsetMetadataOrgs = ToolsetMetadata{
		ID:          "orgs",
		Description: "GitHub Organization related tools",
	}
	ToolsetMetadataActions = ToolsetMetadata{
		ID:          "actions",
		Description: "GitHub Actions workflows and CI/CD operations",
	}
	ToolsetMetadataCodeSecurity = ToolsetMetadata{
		ID:          "code_security",
		Description: "Code security related tools, such as GitHub Code Scanning",
	}
	ToolsetMetadataSecretProtection = ToolsetMetadata{
		ID:          "secret_protection",
		Description: "Secret protection related tools, such as GitHub Secret Scanning",
	}
	ToolsetMetadataDependabot = ToolsetMetadata{
		ID:          "dependabot",
		Description: "Dependabot tools",
	}
	ToolsetMetadataNotifications = ToolsetMetadata{
		ID:          "notifications",
		Description: "GitHub Notifications related tools",
	}
	ToolsetMetadataExperiments = ToolsetMetadata{
		ID:          "experiments",
		Description: "Experimental features that are not considered stable yet",
	}
	ToolsetMetadataDiscussions = ToolsetMetadata{
		ID:          "discussions",
		Description: "GitHub Discussions related tools",
	}
	ToolsetMetadataGists = ToolsetMetadata{
		ID:          "gists",
		Description: "GitHub Gist related tools",
	}
	ToolsetMetadataSecurityAdvisories = ToolsetMetadata{
		ID:          "security_advisories",
		Description: "Security advisories related tools",
	}
	ToolsetMetadataProjects = ToolsetMetadata{
		ID:          "projects",
		Description: "GitHub Projects related tools",
	}
	ToolsetMetadataStargazers = ToolsetMetadata{
		ID:          "stargazers",
		Description: "GitHub Stargazers related tools",
	}
	ToolsetMetadataDynamic = ToolsetMetadata{
		ID:          "dynamic",
		Description: "Discover GitHub MCP tools that can help achieve tasks by enabling additional sets of tools, you can control the enablement of any toolset to access its tools when this toolset is enabled.",
	}
	ToolsetLabels = ToolsetMetadata{
		ID:          "labels",
		Description: "GitHub Labels related tools",
	}
)

func AvailableTools() []ToolsetMetadata {
	return []ToolsetMetadata{
		ToolsetMetadataContext,
		ToolsetMetadataRepos,
		ToolsetMetadataIssues,
		ToolsetMetadataPullRequests,
		ToolsetMetadataUsers,
		ToolsetMetadataOrgs,
		ToolsetMetadataActions,
		ToolsetMetadataCodeSecurity,
		ToolsetMetadataSecretProtection,
		ToolsetMetadataDependabot,
		ToolsetMetadataNotifications,
		ToolsetMetadataExperiments,
		ToolsetMetadataDiscussions,
		ToolsetMetadataGists,
		ToolsetMetadataSecurityAdvisories,
		ToolsetMetadataProjects,
		ToolsetMetadataStargazers,
		ToolsetMetadataDynamic,
		ToolsetLabels,
	}
}

func GetDefaultToolsetIDs() []string {
	return []string{
		ToolsetMetadataContext.ID,
		ToolsetMetadataRepos.ID,
		ToolsetMetadataIssues.ID,
		ToolsetMetadataPullRequests.ID,
		ToolsetMetadataUsers.ID,
	}
}

func DefaultToolsetGroup(readOnly bool, getClient GetClientFn, getGQLClient GetGQLClientFn, getRawClient raw.GetRawClientFn, t translations.TranslationHelperFunc, contentWindowSize int) *toolsets.ToolsetGroup {
	tsg := toolsets.NewToolsetGroup(readOnly)

	// Define all available features with their default state (disabled)
	// Create toolsets
	repos := toolsets.NewToolset(ToolsetMetadataRepos.ID, ToolsetMetadataRepos.Description).
		AddReadTools(
			toolsets.NewServerTool(SearchRepositories(getClient, t)),
			toolsets.NewServerTool(GetFileContents(getClient, getRawClient, t)),
			toolsets.NewServerTool(ListCommits(getClient, t)),
			toolsets.NewServerTool(SearchCode(getClient, t)),
			toolsets.NewServerTool(GetCommit(getClient, t)),
			toolsets.NewServerTool(ListBranches(getClient, t)),
			toolsets.NewServerTool(ListTags(getClient, t)),
			toolsets.NewServerTool(GetTag(getClient, t)),
			toolsets.NewServerTool(ListReleases(getClient, t)),
			toolsets.NewServerTool(GetLatestRelease(getClient, t)),
			toolsets.NewServerTool(GetReleaseByTag(getClient, t)),
		).
		AddWriteTools(
			toolsets.NewServerTool(CreateOrUpdateFile(getClient, t)),
			toolsets.NewServerTool(CreateRepository(getClient, t)),
			toolsets.NewServerTool(ForkRepository(getClient, t)),
			toolsets.NewServerTool(CreateBranch(getClient, t)),
			toolsets.NewServerTool(PushFiles(getClient, t)),
			toolsets.NewServerTool(DeleteFile(getClient, t)),
		).
		AddResourceTemplates(
			toolsets.NewServerResourceTemplate(GetRepositoryResourceContent(getClient, getRawClient, t)),
			toolsets.NewServerResourceTemplate(GetRepositoryResourceBranchContent(getClient, getRawClient, t)),
			toolsets.NewServerResourceTemplate(GetRepositoryResourceCommitContent(getClient, getRawClient, t)),
			toolsets.NewServerResourceTemplate(GetRepositoryResourceTagContent(getClient, getRawClient, t)),
			toolsets.NewServerResourceTemplate(GetRepositoryResourcePrContent(getClient, getRawClient, t)),
		)
	issues := toolsets.NewToolset(ToolsetMetadataIssues.ID, ToolsetMetadataIssues.Description).
		AddReadTools(
			toolsets.NewServerTool(GetIssue(getClient, t)),
			toolsets.NewServerTool(SearchIssues(getClient, t)),
			toolsets.NewServerTool(ListIssues(getGQLClient, t)),
			toolsets.NewServerTool(GetIssueComments(getClient, t)),
			toolsets.NewServerTool(ListIssueTypes(getClient, t)),
			toolsets.NewServerTool(ListSubIssues(getClient, t)),
			toolsets.NewServerTool(GetLabel(getGQLClient, t)),
			toolsets.NewServerTool(ListLabels(getGQLClient, t)),
		).
		AddWriteTools(
			toolsets.NewServerTool(CreateIssue(getClient, t)),
			toolsets.NewServerTool(AddIssueComment(getClient, t)),
			toolsets.NewServerTool(UpdateIssue(getClient, getGQLClient, t)),
			toolsets.NewServerTool(AssignCopilotToIssue(getGQLClient, t)),
			toolsets.NewServerTool(AddSubIssue(getClient, t)),
			toolsets.NewServerTool(RemoveSubIssue(getClient, t)),
			toolsets.NewServerTool(ReprioritizeSubIssue(getClient, t)),
		).AddPrompts(
		toolsets.NewServerPrompt(AssignCodingAgentPrompt(t)),
		toolsets.NewServerPrompt(IssueToFixWorkflowPrompt(t)),
	)
	users := toolsets.NewToolset(ToolsetMetadataUsers.ID, ToolsetMetadataUsers.Description).
		AddReadTools(
			toolsets.NewServerTool(SearchUsers(getClient, t)),
		)
	orgs := toolsets.NewToolset(ToolsetMetadataOrgs.ID, ToolsetMetadataOrgs.Description).
		AddReadTools(
			toolsets.NewServerTool(SearchOrgs(getClient, t)),
		)
	pullRequests := toolsets.NewToolset(ToolsetMetadataPullRequests.ID, ToolsetMetadataPullRequests.Description).
		AddReadTools(
			toolsets.NewServerTool(PullRequestRead(getClient, t)),
			toolsets.NewServerTool(ListPullRequests(getClient, t)),
			toolsets.NewServerTool(SearchPullRequests(getClient, t)),
		).
		AddWriteTools(
			toolsets.NewServerTool(MergePullRequest(getClient, t)),
			toolsets.NewServerTool(UpdatePullRequestBranch(getClient, t)),
			toolsets.NewServerTool(CreatePullRequest(getClient, t)),
			toolsets.NewServerTool(UpdatePullRequest(getClient, getGQLClient, t)),
			toolsets.NewServerTool(RequestCopilotReview(getClient, t)),

			// Reviews
			toolsets.NewServerTool(CreateAndSubmitPullRequestReview(getGQLClient, t)),
			toolsets.NewServerTool(CreatePendingPullRequestReview(getGQLClient, t)),
			toolsets.NewServerTool(AddCommentToPendingReview(getGQLClient, t)),
			toolsets.NewServerTool(SubmitPendingPullRequestReview(getGQLClient, t)),
			toolsets.NewServerTool(DeletePendingPullRequestReview(getGQLClient, t)),
		)
	codeSecurity := toolsets.NewToolset(ToolsetMetadataCodeSecurity.ID, ToolsetMetadataCodeSecurity.Description).
		AddReadTools(
			toolsets.NewServerTool(GetCodeScanningAlert(getClient, t)),
			toolsets.NewServerTool(ListCodeScanningAlerts(getClient, t)),
		)
	secretProtection := toolsets.NewToolset(ToolsetMetadataSecretProtection.ID, ToolsetMetadataSecretProtection.Description).
		AddReadTools(
			toolsets.NewServerTool(GetSecretScanningAlert(getClient, t)),
			toolsets.NewServerTool(ListSecretScanningAlerts(getClient, t)),
		)
	dependabot := toolsets.NewToolset(ToolsetMetadataDependabot.ID, ToolsetMetadataDependabot.Description).
		AddReadTools(
			toolsets.NewServerTool(GetDependabotAlert(getClient, t)),
			toolsets.NewServerTool(ListDependabotAlerts(getClient, t)),
		)

	notifications := toolsets.NewToolset(ToolsetMetadataNotifications.ID, ToolsetMetadataNotifications.Description).
		AddReadTools(
			toolsets.NewServerTool(ListNotifications(getClient, t)),
			toolsets.NewServerTool(GetNotificationDetails(getClient, t)),
		).
		AddWriteTools(
			toolsets.NewServerTool(DismissNotification(getClient, t)),
			toolsets.NewServerTool(MarkAllNotificationsRead(getClient, t)),
			toolsets.NewServerTool(ManageNotificationSubscription(getClient, t)),
			toolsets.NewServerTool(ManageRepositoryNotificationSubscription(getClient, t)),
		)

	discussions := toolsets.NewToolset(ToolsetMetadataDiscussions.ID, ToolsetMetadataDiscussions.Description).
		AddReadTools(
			toolsets.NewServerTool(ListDiscussions(getGQLClient, t)),
			toolsets.NewServerTool(GetDiscussion(getGQLClient, t)),
			toolsets.NewServerTool(GetDiscussionComments(getGQLClient, t)),
			toolsets.NewServerTool(ListDiscussionCategories(getGQLClient, t)),
		)

	actions := toolsets.NewToolset(ToolsetMetadataActions.ID, ToolsetMetadataActions.Description).
		AddReadTools(
			toolsets.NewServerTool(ListWorkflows(getClient, t)),
			toolsets.NewServerTool(ListWorkflowRuns(getClient, t)),
			toolsets.NewServerTool(GetWorkflowRun(getClient, t)),
			toolsets.NewServerTool(GetWorkflowRunLogs(getClient, t)),
			toolsets.NewServerTool(ListWorkflowJobs(getClient, t)),
			toolsets.NewServerTool(GetJobLogs(getClient, t, contentWindowSize)),
			toolsets.NewServerTool(ListWorkflowRunArtifacts(getClient, t)),
			toolsets.NewServerTool(DownloadWorkflowRunArtifact(getClient, t)),
			toolsets.NewServerTool(GetWorkflowRunUsage(getClient, t)),
		).
		AddWriteTools(
			toolsets.NewServerTool(RunWorkflow(getClient, t)),
			toolsets.NewServerTool(RerunWorkflowRun(getClient, t)),
			toolsets.NewServerTool(RerunFailedJobs(getClient, t)),
			toolsets.NewServerTool(CancelWorkflowRun(getClient, t)),
			toolsets.NewServerTool(DeleteWorkflowRunLogs(getClient, t)),
		)

	securityAdvisories := toolsets.NewToolset(ToolsetMetadataSecurityAdvisories.ID, ToolsetMetadataSecurityAdvisories.Description).
		AddReadTools(
			toolsets.NewServerTool(ListGlobalSecurityAdvisories(getClient, t)),
			toolsets.NewServerTool(GetGlobalSecurityAdvisory(getClient, t)),
			toolsets.NewServerTool(ListRepositorySecurityAdvisories(getClient, t)),
			toolsets.NewServerTool(ListOrgRepositorySecurityAdvisories(getClient, t)),
		)

	// Keep experiments alive so the system doesn't error out when it's always enabled
	experiments := toolsets.NewToolset(ToolsetMetadataExperiments.ID, ToolsetMetadataExperiments.Description)

	contextTools := toolsets.NewToolset(ToolsetMetadataContext.ID, ToolsetMetadataContext.Description).
		AddReadTools(
			toolsets.NewServerTool(GetMe(getClient, t)),
			toolsets.NewServerTool(GetTeams(getClient, getGQLClient, t)),
			toolsets.NewServerTool(GetTeamMembers(getGQLClient, t)),
		)

	gists := toolsets.NewToolset(ToolsetMetadataGists.ID, ToolsetMetadataGists.Description).
		AddReadTools(
			toolsets.NewServerTool(ListGists(getClient, t)),
		).
		AddWriteTools(
			toolsets.NewServerTool(CreateGist(getClient, t)),
			toolsets.NewServerTool(UpdateGist(getClient, t)),
		)

	projects := toolsets.NewToolset(ToolsetMetadataProjects.ID, ToolsetMetadataProjects.Description).
		AddReadTools(
			toolsets.NewServerTool(ListProjects(getClient, t)),
			toolsets.NewServerTool(GetProject(getClient, t)),
			toolsets.NewServerTool(ListProjectFields(getClient, t)),
			toolsets.NewServerTool(GetProjectField(getClient, t)),
			toolsets.NewServerTool(ListProjectItems(getClient, t)),
			toolsets.NewServerTool(GetProjectItem(getClient, t)),
		).
		AddWriteTools(
			toolsets.NewServerTool(AddProjectItem(getClient, t)),
			toolsets.NewServerTool(DeleteProjectItem(getClient, t)),
			toolsets.NewServerTool(UpdateProjectItem(getClient, t)),
		)
	stargazers := toolsets.NewToolset(ToolsetMetadataStargazers.ID, ToolsetMetadataStargazers.Description).
		AddReadTools(
			toolsets.NewServerTool(ListStarredRepositories(getClient, t)),
		).
		AddWriteTools(
			toolsets.NewServerTool(StarRepository(getClient, t)),
			toolsets.NewServerTool(UnstarRepository(getClient, t)),
		)
	labels := toolsets.NewToolset(ToolsetLabels.ID, ToolsetLabels.Description).
		AddReadTools(
			// get
			toolsets.NewServerTool(GetLabel(getGQLClient, t)),
			// list labels on repo or issue
			toolsets.NewServerTool(ListLabels(getGQLClient, t)),
		).
		AddWriteTools(
			// create or update
			toolsets.NewServerTool(LabelWrite(getGQLClient, t)),
		)
	// Add toolsets to the group
	tsg.AddToolset(contextTools)
	tsg.AddToolset(repos)
	tsg.AddToolset(issues)
	tsg.AddToolset(orgs)
	tsg.AddToolset(users)
	tsg.AddToolset(pullRequests)
	tsg.AddToolset(actions)
	tsg.AddToolset(codeSecurity)
	tsg.AddToolset(secretProtection)
	tsg.AddToolset(dependabot)
	tsg.AddToolset(notifications)
	tsg.AddToolset(experiments)
	tsg.AddToolset(discussions)
	tsg.AddToolset(gists)
	tsg.AddToolset(securityAdvisories)
	tsg.AddToolset(projects)
	tsg.AddToolset(stargazers)
	tsg.AddToolset(labels)

	return tsg
}

// InitDynamicToolset creates a dynamic toolset that can be used to enable other toolsets, and so requires the server and toolset group as arguments
func InitDynamicToolset(s *server.MCPServer, tsg *toolsets.ToolsetGroup, t translations.TranslationHelperFunc) *toolsets.Toolset {
	// Create a new dynamic toolset
	// Need to add the dynamic toolset last so it can be used to enable other toolsets
	dynamicToolSelection := toolsets.NewToolset(ToolsetMetadataDynamic.ID, ToolsetMetadataDynamic.Description).
		AddReadTools(
			toolsets.NewServerTool(ListAvailableToolsets(tsg, t)),
			toolsets.NewServerTool(GetToolsetsTools(tsg, t)),
			toolsets.NewServerTool(EnableToolset(s, tsg, t)),
		)

	dynamicToolSelection.Enabled = true
	return dynamicToolSelection
}

// ToBoolPtr converts a bool to a *bool pointer.
func ToBoolPtr(b bool) *bool {
	return &b
}

// ToStringPtr converts a string to a *string pointer.
// Returns nil if the string is empty.
func ToStringPtr(s string) *string {
	if s == "" {
		return nil
	}
	return &s
}

// GenerateToolsetsHelp generates the help text for the toolsets flag
func GenerateToolsetsHelp() string {
	// Format default tools
	defaultTools := strings.Join(GetDefaultToolsetIDs(), ", ")

	// Format available tools with line breaks for better readability
	allTools := AvailableTools()
	var availableToolsLines []string
	const maxLineLength = 70
	currentLine := ""

	for i, tool := range allTools {
		switch {
		case i == 0:
			currentLine = tool.ID
		case len(currentLine)+len(tool.ID)+2 <= maxLineLength:
			currentLine += ", " + tool.ID
		default:
			availableToolsLines = append(availableToolsLines, currentLine)
			currentLine = tool.ID
		}
	}
	if currentLine != "" {
		availableToolsLines = append(availableToolsLines, currentLine)
	}

	availableTools := strings.Join(availableToolsLines, ",\n\t     ")

	toolsetsHelp := fmt.Sprintf("Comma-separated list of tool groups to enable (no spaces).\n"+
		"Default: %s\n"+
		"Available: %s\n", defaultTools, availableTools) +
		"To enable all tools, use \"all\"."
	return toolsetsHelp
}