package tools

import (
	"context"
	"encoding/json"

	"gitea.d-ma.be/mathias/gitea-mcp/internal/allowlist"
	"gitea.d-ma.be/mathias/gitea-mcp/internal/gitea"
	"gitea.d-ma.be/mathias/gitea-mcp/internal/registry"
)

type RepoStatus struct {
	c *gitea.Client
	a *allowlist.Allowlist
}

func NewRepoStatus(c *gitea.Client, a *allowlist.Allowlist) *RepoStatus {
	return &RepoStatus{c: c, a: a}
}

func (t *RepoStatus) Descriptor() registry.ToolDescriptor {
	return registry.ToolDescriptor{
		Name:        "repo_status",
		Description: "Get repo state in one call: all branches, open PRs, and protection rules for a target branch. Use this first to decide whether to use feature-branch or trunk-based development.",
		InputSchema: json.RawMessage(`{
			"type":"object",
			"properties":{
				"owner":{"type":"string"},
				"name":{"type":"string"},
				"branch":{"type":"string"}
			},
			"required":["owner","name"]
		}`),
	}
}

type repoStatusArgs struct {
	Owner  string `json:"owner"`
	Name   string `json:"name"`
	Branch string `json:"branch"`
}

func (t *RepoStatus) Call(ctx context.Context, raw json.RawMessage) (json.RawMessage, error) {
	var args repoStatusArgs
	if err := parseArgs(raw, &args); err != nil {
		return nil, err
	}
	if err := t.a.Check(args.Owner); err != nil {
		return nil, err
	}

	branch := args.Branch
	if branch == "" {
		var err error
		branch, err = t.c.DefaultBranch(ctx, args.Owner, args.Name)
		if err != nil {
			return nil, err
		}
	}

	branches, err := t.c.ListBranches(ctx, args.Owner, args.Name, 1, 50)
	if err != nil {
		return nil, err
	}

	prs, err := t.c.ListPullRequests(ctx, args.Owner, args.Name, "open", "", 1, 50)
	if err != nil {
		return nil, err
	}

	bp, err := t.c.GetBranchProtection(ctx, args.Owner, args.Name, branch)
	if err != nil {
		return nil, err
	}

	branchList := make([]map[string]any, len(branches))
	for i, b := range branches {
		branchList[i] = map[string]any{"name": b.Name, "sha": b.Commit.ID}
	}

	prList := make([]map[string]any, len(prs))
	for i, pr := range prs {
		prList[i] = map[string]any{
			"number":      pr.Number,
			"title":       pr.Title,
			"state":       pr.State,
			"head_branch": pr.Head.Ref,
			"base_branch": pr.Base.Ref,
			"draft":       pr.Draft,
			"html_url":    pr.HTMLURL,
		}
	}

	return textOK(map[string]any{
		"branches": branchList,
		"open_prs": prList,
		"protection": map[string]any{
			"protected":          bp.Protected,
			"required_approvals": bp.RequiredApprovals,
			"push_whitelist":     bp.PushWhitelist,
			"merge_whitelist":    bp.MergeWhitelist,
		},
	})
}