// <copyright file="PlanAdminEndpoints.cs" company="Stella Operations">
// Copyright (c) Stella Operations. Licensed under BUSL-1.1.
// </copyright>


using Microsoft.AspNetCore.Http.HttpResults;
using Microsoft.AspNetCore.Mvc;
using System.Security.Claims;
using static StellaOps.Localization.T;

namespace StellaOps.Registry.TokenService.Admin;

/// <summary>
/// Minimal API endpoint mappings for Plan Rule administration.
/// </summary>
public static class PlanAdminEndpoints
{
    /// <summary>
    /// Maps the plan admin endpoints to the application.
    /// </summary>
    public static void MapPlanAdminEndpoints(this WebApplication app)
    {
        var group = app.MapGroup("/api/admin/plans")
            .WithTags("Plan Administration")
            .RequireAuthorization("registry.admin");

        group.MapGet("/", ListPlans)
            .WithName("ListPlans")
            .WithDescription("Lists all plan rules ordered by name.")
            .Produces<IReadOnlyList<PlanRuleDto>>(StatusCodes.Status200OK)
            .ProducesProblem(StatusCodes.Status401Unauthorized)
            .ProducesProblem(StatusCodes.Status403Forbidden);

        group.MapGet("/{planId}", GetPlan)
            .WithName("GetPlan")
            .WithDescription("Gets a plan rule by ID.")
            .Produces<PlanRuleDto>(StatusCodes.Status200OK)
            .ProducesProblem(StatusCodes.Status404NotFound)
            .ProducesProblem(StatusCodes.Status401Unauthorized)
            .ProducesProblem(StatusCodes.Status403Forbidden);

        group.MapPost("/", CreatePlan)
            .WithName("CreatePlan")
            .WithDescription("Creates a new plan rule.")
            .Produces<PlanRuleDto>(StatusCodes.Status201Created)
            .ProducesProblem(StatusCodes.Status400BadRequest)
            .ProducesProblem(StatusCodes.Status409Conflict)
            .ProducesProblem(StatusCodes.Status401Unauthorized)
            .ProducesProblem(StatusCodes.Status403Forbidden);

        group.MapPut("/{planId}", UpdatePlan)
            .WithName("UpdatePlan")
            .WithDescription("Updates an existing plan rule. Requires version for optimistic concurrency.")
            .Produces<PlanRuleDto>(StatusCodes.Status200OK)
            .ProducesProblem(StatusCodes.Status400BadRequest)
            .ProducesProblem(StatusCodes.Status404NotFound)
            .ProducesProblem(StatusCodes.Status409Conflict)
            .ProducesProblem(StatusCodes.Status401Unauthorized)
            .ProducesProblem(StatusCodes.Status403Forbidden);

        group.MapDelete("/{planId}", DeletePlan)
            .WithName("DeletePlan")
            .WithDescription("Deletes a plan rule.")
            .Produces(StatusCodes.Status204NoContent)
            .ProducesProblem(StatusCodes.Status404NotFound)
            .ProducesProblem(StatusCodes.Status401Unauthorized)
            .ProducesProblem(StatusCodes.Status403Forbidden);

        group.MapPost("/validate", ValidatePlan)
            .WithName("ValidatePlan")
            .WithDescription("Validates a plan rule without saving. Optionally evaluates test scopes.")
            .Produces<ValidationResult>(StatusCodes.Status200OK)
            .ProducesProblem(StatusCodes.Status400BadRequest)
            .ProducesProblem(StatusCodes.Status401Unauthorized)
            .ProducesProblem(StatusCodes.Status403Forbidden);

        group.MapGet("/audit", GetAuditHistory)
            .WithName("GetPlanAuditHistory")
            .WithDescription("Gets audit history for plan changes. Optionally filter by plan ID.")
            .Produces<PaginatedResponse<PlanAuditEntry>>(StatusCodes.Status200OK)
            .ProducesProblem(StatusCodes.Status401Unauthorized)
            .ProducesProblem(StatusCodes.Status403Forbidden);
    }

    private static async Task<Ok<IReadOnlyList<PlanRuleDto>>> ListPlans(
        [FromServices] IPlanRuleStore store,
        CancellationToken cancellationToken)
    {
        var plans = await store.GetAllAsync(cancellationToken);
        return TypedResults.Ok(plans);
    }

    private static async Task<Results<Ok<PlanRuleDto>, NotFound<ProblemDetails>>> GetPlan(
        string planId,
        [FromServices] IPlanRuleStore store,
        CancellationToken cancellationToken)
    {
        var plan = await store.GetByIdAsync(planId, cancellationToken);
        if (plan is null)
        {
            return TypedResults.NotFound(CreateProblemDetails(
                StatusCodes.Status404NotFound,
                _t("registry.error.plan_not_found"),
                _t("registry.error.plan_not_found_detail", planId)));
        }

        return TypedResults.Ok(plan);
    }

    private static async Task<Results<Created<PlanRuleDto>, BadRequest<ProblemDetails>, Conflict<ProblemDetails>>> CreatePlan(
        [FromBody] CreatePlanRequest request,
        [FromServices] IPlanRuleStore store,
        [FromServices] PlanValidator validator,
        HttpContext context,
        CancellationToken cancellationToken)
    {
        // Validate the request
        var validationRequest = new ValidatePlanRequest { Plan = request };
        var validationResult = validator.Validate(validationRequest);
        if (!validationResult.Valid)
        {
            return TypedResults.BadRequest(CreateProblemDetails(
                StatusCodes.Status400BadRequest,
                _t("registry.error.validation_failed"),
                _t("registry.validation.plan_request_invalid"),
                validationResult.Errors));
        }

        var actor = GetActorFromContext(context);

        try
        {
            var created = await store.CreateAsync(request, actor, cancellationToken);
            return TypedResults.Created($"/api/admin/plans/{created.Id}", created);
        }
        catch (PlanNameConflictException ex)
        {
            return TypedResults.Conflict(CreateProblemDetails(
                StatusCodes.Status409Conflict,
                _t("registry.error.plan_name_conflict"),
                ex.Message));
        }
    }

    private static async Task<Results<Ok<PlanRuleDto>, BadRequest<ProblemDetails>, NotFound<ProblemDetails>, Conflict<ProblemDetails>>> UpdatePlan(
        string planId,
        [FromBody] UpdatePlanRequest request,
        [FromServices] IPlanRuleStore store,
        [FromServices] PlanValidator validator,
        HttpContext context,
        CancellationToken cancellationToken)
    {
        // Validate the request if it includes full plan fields
        if (request.Repositories is not null || request.Name is not null)
        {
            var tempPlan = new CreatePlanRequest
            {
                Name = request.Name ?? "temp",
                Description = request.Description,
                Repositories = request.Repositories ?? [],
                Allowlist = request.Allowlist ?? [],
                RateLimit = request.RateLimit,
            };
            var validationRequest = new ValidatePlanRequest { Plan = tempPlan };
            var validationResult = validator.Validate(validationRequest);

            // Filter out errors for fields not being updated
            var relevantErrors = validationResult.Errors
                .Where(e => request.Name is not null || !e.Field.StartsWith("plan.name", StringComparison.Ordinal))
                .Where(e => request.Repositories is not null || !e.Field.StartsWith("plan.repositories", StringComparison.Ordinal))
                .ToList();

            if (relevantErrors.Count > 0)
            {
                return TypedResults.BadRequest(CreateProblemDetails(
                    StatusCodes.Status400BadRequest,
                    _t("registry.error.validation_failed"),
                    _t("registry.validation.plan_update_invalid"),
                    relevantErrors));
            }
        }

        var actor = GetActorFromContext(context);

        try
        {
            var updated = await store.UpdateAsync(planId, request, actor, cancellationToken);
            return TypedResults.Ok(updated);
        }
        catch (PlanNotFoundException)
        {
            return TypedResults.NotFound(CreateProblemDetails(
                StatusCodes.Status404NotFound,
                _t("registry.error.plan_not_found"),
                _t("registry.error.plan_not_found_detail", planId)));
        }
        catch (PlanVersionConflictException ex)
        {
            return TypedResults.Conflict(CreateProblemDetails(
                StatusCodes.Status409Conflict,
                _t("registry.error.plan_version_conflict"),
                ex.Message));
        }
        catch (PlanNameConflictException ex)
        {
            return TypedResults.Conflict(CreateProblemDetails(
                StatusCodes.Status409Conflict,
                _t("registry.error.plan_name_conflict"),
                ex.Message));
        }
    }

    private static async Task<Results<NoContent, NotFound<ProblemDetails>>> DeletePlan(
        string planId,
        [FromServices] IPlanRuleStore store,
        HttpContext context,
        CancellationToken cancellationToken)
    {
        var actor = GetActorFromContext(context);
        var deleted = await store.DeleteAsync(planId, actor, cancellationToken);

        if (!deleted)
        {
            return TypedResults.NotFound(CreateProblemDetails(
                StatusCodes.Status404NotFound,
                _t("registry.error.plan_not_found"),
                _t("registry.error.plan_not_found_detail", planId)));
        }

        return TypedResults.NoContent();
    }

    private static Ok<ValidationResult> ValidatePlan(
        [FromBody] ValidatePlanRequest request,
        [FromServices] PlanValidator validator)
    {
        var result = validator.Validate(request);
        return TypedResults.Ok(result);
    }

    private static async Task<Ok<PaginatedResponse<PlanAuditEntry>>> GetAuditHistory(
        [FromServices] IPlanRuleStore store,
        [FromQuery] string? planId = null,
        [FromQuery] int page = 1,
        [FromQuery] int pageSize = 50,
        CancellationToken cancellationToken = default)
    {
        // Clamp page size
        pageSize = Math.Clamp(pageSize, 1, 100);
        page = Math.Max(1, page);

        var entries = await store.GetAuditHistoryAsync(planId, page, pageSize, cancellationToken);
        var totalCount = await store.GetAuditHistoryCountAsync(planId, cancellationToken);

        var response = new PaginatedResponse<PlanAuditEntry>
        {
            Items = entries,
            TotalCount = totalCount,
            Page = page,
            PageSize = pageSize,
        };

        return TypedResults.Ok(response);
    }

    private static string GetActorFromContext(HttpContext context)
    {
        var user = context.User;
        var sub = user.FindFirstValue(ClaimTypes.NameIdentifier) ?? user.FindFirstValue("sub");
        var name = user.FindFirstValue(ClaimTypes.Name) ?? user.FindFirstValue("name");

        return sub ?? name ?? "anonymous";
    }

    private static ProblemDetails CreateProblemDetails(
        int statusCode,
        string title,
        string detail,
        IReadOnlyList<ValidationError>? errors = null)
    {
        var problem = new ProblemDetails
        {
            Status = statusCode,
            Title = title,
            Detail = detail,
        };

        if (errors is not null && errors.Count > 0)
        {
            problem.Extensions["errors"] = errors;
        }

        return problem;
    }
}