package site

import (
	"context"
	"encoding/json"
	"path"
	"sort"
	"strconv"
)

type repositoryNavigation struct {
	DefaultBranch string   `json:"defaultBranch"`
	Branches      []string `json:"branches"`
}

type fileNavigation struct {
	Files []fileNavigationEntry `json:"files"`
}

type fileNavigationEntry struct {
	Path string `json:"path"`
	URL  string `json:"url"`
}

func branchStylePage(branch string, commitCount int) Page {
	return Page{
		Route:       path.Join(".dumbforge/branches", branchRouteSegment(branch)+".css"),
		Body:        []byte(`[data-commit-count]::before { content: "` + strconv.Itoa(commitCount) + `"; }` + "\n"),
		ContentType: "text/css; charset=utf-8",
		Cache:       siteCache,
	}
}

func (g *Generator) SetBranches(branches []string, defaultBranch string) {
	seen := map[string]struct{}{}
	g.Branches = g.Branches[:0]
	for _, branch := range branches {
		if branch == "" {
			continue
		}
		if _, exists := seen[branch]; exists {
			continue
		}
		seen[branch] = struct{}{}
		g.Branches = append(g.Branches, branch)
	}
	sort.Strings(g.Branches)
	g.DefaultBranch = defaultBranch
	if g.DefaultBranch == "" && len(g.Branches) > 0 {
		g.DefaultBranch = g.Branches[0]
	}
}

func (g *Generator) ensureBranch(branch string, isHead bool) {
	if isHead || g.DefaultBranch == "" {
		g.DefaultBranch = branch
	}
	for _, existing := range g.Branches {
		if existing == branch {
			return
		}
	}
	g.Branches = append(g.Branches, branch)
	sort.Strings(g.Branches)
}

func (g *Generator) filesPage(ctx context.Context, branch, oid string) (Page, error) {
	entries, err := g.listTreeRecursive(ctx, oid)
	if err != nil {
		return Page{}, err
	}
	g.decorateSubmodules(ctx, oid, "", entries)
	manifest := fileNavigation{}
	for _, entry := range entries {
		if entry.Type == "tree" {
			continue
		}
		entryURL := routeURL(g.BaseURL, path.Join("blob", branchRouteSegment(branch), entry.Name))
		if entry.SubmoduleURL != "" {
			entryURL = entry.SubmoduleURL
		}
		manifest.Files = append(manifest.Files, fileNavigationEntry{Path: entry.Name, URL: entryURL})
	}
	sort.Slice(manifest.Files, func(i, j int) bool {
		return manifest.Files[i].Path < manifest.Files[j].Path
	})
	body, err := json.Marshal(manifest)
	if err != nil {
		return Page{}, err
	}
	return Page{
		Route:       path.Join(".dumbforge/files", branchRouteSegment(branch)+".json"),
		Body:        body,
		ContentType: "application/json; charset=utf-8",
		Cache:       siteCache,
	}, nil
}

func (g *Generator) RepositoryNavigationBuild(deletedBranches []string) (Build, error) {
	manifest := repositoryNavigation{
		DefaultBranch: g.DefaultBranch,
		Branches:      append([]string(nil), g.Branches...),
	}
	body, err := json.Marshal(manifest)
	if err != nil {
		return Build{}, err
	}
	build := Build{Pages: []Page{{
		Route:       ".dumbforge/repository.json",
		Body:        body,
		ContentType: "application/json; charset=utf-8",
		Cache:       siteCache,
	}}}
	for _, branch := range deletedBranches {
		build.Deletes = append(build.Deletes,
			path.Join(".dumbforge/files", branchRouteSegment(branch)+".json"),
			path.Join(".dumbforge/branches", branchRouteSegment(branch)+".css"),
		)
	}
	return build, nil
}