package tui

import (
	"context"
	"fmt"
	"path/filepath"
	"strings"

	tea "charm.land/bubbletea/v2"

	"superwork-tui/internal/auth"
	"superwork-tui/internal/cc"
	"superwork-tui/internal/config"
	"superwork-tui/internal/files"
	"superwork-tui/internal/git"
	"superwork-tui/internal/gitea"
	"superwork-tui/internal/issue"
)

type branchSyncStatusMsg struct {
	status git.BranchSyncStatus
	err    error
}

type branchSyncDoneMsg struct {
	devBranch       string
	autoBuildBranch string
	err             error
}

type envLockDoneMsg struct {
	locked bool
	result files.EnvLockResult
	err    error
}

type prDiffResultMsg struct {
	issueNumber int
	prDiffFile  string
	err         error
}

// branchSyncCheckCmd checks branch sync status and returns branchSyncStatusMsg.
func branchSyncCheckCmd() tea.Cmd {
	return func() tea.Msg {
		ctx := context.Background()
		root, err := workspaceRootFn()
		if err != nil {
			return branchSyncStatusMsg{err: err}
		}
		settings, err := config.Load()
		if err != nil {
			return branchSyncStatusMsg{err: fmt.Errorf("load settings: %w", err)}
		}
		// Empty autoBuildBranch means "follow devBranch"; resolving here makes
		// the check fall into the same-branch (Unavailable) path, matching TS.
		autoBuildBranch := settings.AutoBuildBranch
		if autoBuildBranch == "" {
			autoBuildBranch = settings.DevBranch
		}
		status, err := git.CheckBranchSync(ctx, git.BranchSyncOpts{
			WorkspaceRoot:   root,
			DevBranch:       settings.DevBranch,
			AutoBuildBranch: autoBuildBranch,
		})
		return branchSyncStatusMsg{status: status, err: err}
	}
}

// branchSyncRunCmd pushes devBranch to autoBuildBranch, resolving workspace root internally.
func branchSyncRunCmd(devBranch, autoBuildBranch string) tea.Cmd {
	return func() tea.Msg {
		ctx := context.Background()
		root, err := workspaceRootFn()
		if err != nil {
			return branchSyncDoneMsg{devBranch: devBranch, autoBuildBranch: autoBuildBranch, err: err}
		}
		err = git.RunBranchSync(ctx, git.BranchSyncOpts{
			WorkspaceRoot:   root,
			DevBranch:       devBranch,
			AutoBuildBranch: autoBuildBranch,
		})
		return branchSyncDoneMsg{devBranch: devBranch, autoBuildBranch: autoBuildBranch, err: err}
	}
}

// envLockToggleCmd locks or unlocks .env files based on current state.
func envLockToggleCmd(currentlyLocked bool) tea.Cmd {
	return func() tea.Msg {
		root, err := workspaceRootFn()
		if err != nil {
			return envLockDoneMsg{err: err}
		}
		var result files.EnvLockResult
		if currentlyLocked {
			result, err = files.UnlockEnvFiles(root)
			return envLockDoneMsg{locked: false, result: result, err: err}
		}
		result, err = files.LockEnvFiles(root)
		return envLockDoneMsg{locked: true, result: result, err: err}
	}
}

// prDiffSummaryCmd asks Claude to summarize the PR diff and write it to docs/pr-diff/<branch>.md.
func prDiffSummaryCmd(iss issue.Issue) tea.Cmd {
	return func() tea.Msg {
		ctx := context.Background()
		root, err := workspaceRootFn()
		if err != nil {
			return prDiffResultMsg{issueNumber: iss.Number, err: err}
		}

		safeBranch := strings.ReplaceAll(iss.Branch, "/", "-")
		outFile := filepath.Join("docs", "pr-diff", safeBranch+".md")

		prompt := fmt.Sprintf(
			"请阅读 PR #%s（分支 %s）的变更，并将综合摘要写入 %s。"+
				"摘要应包括：改动内容、改动原因、关键技术决策以及测试方案。",
			iss.PR, iss.Branch, outFile,
		)

		_, spawnErr := cc.SpawnClaude(ctx, cc.Opts{
			Prompt: prompt,
			Cwd:    root,
		})
		if spawnErr != nil {
			return prDiffResultMsg{issueNumber: iss.Number, err: spawnErr}
		}

		// Persist prDiffFile to Gitea state JSON (best-effort).
		remote, rErr := git.DetectRepo(root)
		if rErr == nil {
			token, tErr := auth.ResolveGiteaToken(remote.Host)
			if tErr == nil {
				client := gitea.New(remote.Host, token)
				_ = issue.MergeStateJSON(ctx, client, remote.Owner, remote.Repo, iss.Number, map[string]any{
					"prDiffFile": outFile,
				})
			}
		}

		return prDiffResultMsg{issueNumber: iss.Number, prDiffFile: outFile}
	}
}